Unraveling the tumor-promoting role of wildtype Isocitrate dehydrogenase 1 (IDH1) in human gliomas

Unraveling the tumor-promoting role of wildtype Isocitrate dehydrogenase 1 (IDH1) in human gliomas | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Unraveling the tumor-promoting role of wildtype Isocitrate dehydrogenase 1 (IDH1) in human gliomas Xiang Li, Yiran Tao, Yuan Lyu, Junqi Li, Wulong Liang, Wanqing Liu, and 12 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4043926/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Isocitrate dehydrogenase 1 ( IDH1 ) mutations are discovered in most grade Ⅱ gliomas (71%-78%), grade Ⅲ gliomas (62%-78%) and secondary glioblastomas (88%), and have received lots of attention in recent years. However, the tumor-promoting role of wildtype IDH1 still need to be further investigated. In this article, we found wildtype IDH1 mRNA and protein levels were both elevated in glioma by using bioinformatic analysis, Besides, IDH1 mutation reduced the expression of wildtype IDH1 in U87-R132H cell line. Furthermore, the expression of wildtype IDH1 also increased along with the increase of clinical grades of glioma. Cell function and signaling pathways enrichment analyses were enriched in metabolic processes, phosphatase complex, TCA, DNA replication, p53 signaling pathway, Notch signaling pathway, et al. Single-cell sequencing analysis revealed that high expression of wildtype IDH1 correlated with cell cycle, metastasis, EMT, proliferation, invasion, stemness, and DNA damage. Besides, wildtype IDH1 promoted GBM cell viability, migration, and radioresistance in vitro. Wildtype IDH1 was significantly relevant with diagnosis, prognosis, and survival probability of glioma patients. Therefore, wildtype IDH1 could be an underlying target for glioma therapy. Biological sciences/Cancer Biological sciences/Cancer/Cns cancer wildtype IDH1 mutant IDH1 glioma TCGA prognosis proliferation migration radioresistance Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Introduction In 2021 WHO classification of tumors of the central nervous system, the tumor that previously known as glioblastoma are now divided into two separate diagnoses based on the mutant status of isocitrate dehydrogenase ( IDH ), namely: glioblastoma (GBM), IDH -wildtype, 4 grade; astrocytoma, IDH -mutant, 4 grade ( 1 ). As a member of IDH family, isocitrate dehydrogenase 1 (IDH1) is an enzyme that plays a pivotal role in the tricarboxylic acid (TCA) cycle and redox regulation ( 2 ). The wildtype IDH1, encoded by the IDH1 gene located on chromosome 2q34, catalyzes the conversion of isocitrate to α-ketoglutarate (α-KG), simultaneously generating nicotinamide adenine dinucleotide phosphate (NADPH), in the cytoplasm and peroxisomes during cellular metabolism ( 2 ). Compared with wildtype IDH1 , IDH1 mutations (primarily R132H variant) lead to a gain-of-function with the production of oncometabolite 2-hydroxyglutarate (2-HG) instead of α-KG, which disrupts normal metabolic processes and contributes to the initiation and progression of tumors ( 3 – 7 ). IDH1 mutations are found in approximately 80% grade Ⅱ-Ⅲ gliomas and second GBMs ( 5 , 8 , 9 ). Besides, the presence of IDH1 mutations has been associated with better prognosis in glioma ( 10 – 12 ). However, the cognition of wildtype IDH1 role in tumors is relatively little. The IDH1 wild type is almost exclusively enriched in primary GBM, which distinctly contrasts with the higher frequency of IDH1 mutations in secondary GBMs and other lower-grade gliomas ( 13 ). Recent advancements emphasized the multifaceted characteristics of wildtype IDH1, extending beyond normal metabolic functions. For instance, wildtype IDH1 maintains tumorigenesis of non-small cell lung cancer (NSCLC) and enhances gemcitabine chemoresistance by activating serine biosynthesis ( 14 ). Wildtype IDH1 are also tightly associated with tumor proliferation and migration ( 15 – 17 ). To sum up, the tumor-promoting role of wildtype IDH1 has been gradually recognized. In this present study, we showed that wildtype IDH1 was aberrantly high expression in high-grade glioma tissues especially GBM. We assessed the prognostic value of wildtype IDH1 in glioma and the biological function in GBM cells. Enriched function and signal pathways upon IDH1 expression indicated that IDH1 may participate in the progress of various metabolic processes, phosphatase complex, ubiquitin ligase complex, TCA, p53 signaling pathway, Notch signaling pathway, and DNA replication. Single-cell analysis of IDH1 revealed that IDH1 involved in the progress of cell cycle, metastasis, EMT, proliferation, invasion, stemness, and DNA damage. Our data may provide new insights into the role of wildtype IDH1 in the progression of glioma and present a promising strategy for glioma therapy involving IDH1 blockade. Materials and methods Gene expression analysis The public databases TIMER2.0 ( http://timer.cistrome.org/ ) and Gene Expression Profiling Interactive Analysis 2 (GEPIA2.0, http://gepia2.cancer-pku.cn/ ) were respectively used to analyze the different expression profiles of IDH1 between pan-cancers and adjacent normal tissues, as well as the relationship between IDH1 expression and patients’ pathological stages in TCGA cancers. Public database The Cancer Genome Atlas (TCGA, https://portal.gdc.cancer.gov ) was also used to assess the IDH1 expression in different tumor pathological stages across TCGA tumor types. The public database Chinese Glioma Genome Atlas (CGGA, http://www.cgga.org.cn/ ) was also used to assess the IDH1 expression in different pathological stages and WHO grades of glioma. Public database The Human Protein Atlas (HPA, https://www.proteinatlas.org/ ) was further used to confirm the intensity of IDH1 immunohistochemical staining in several tumor tissues, including renal cancer, skin cancer, and stomach cancer, lung cancer, glioma, and breast cancer. Survival analysis The expression of IDH1 on the patients’ prognostic values, including overall survival (OS) and progression free interval (PFI), was obtained from GEPIA2.0. TCGA tumor patients were divided into the high-expression and low-expression cohorts based on the cut-off values (50% and 50%). Genetic alteration analysis The public cBioPortal ( https://www.cbioportal.org/ ) was used to collect the alteration frequency, mutation type, mutation site information, and three-dimensional (3D) structure of IDH1. Single-cell RNA sequencing As a public single-cell sequencing database, CancerSEA ( http://biocc.hrbmu.edu.cn/CancerSEA/ ) could provide various status of cancer cells in single-cell level. The correlation between IDH1 expression and various cancer cells malignant phenotypes was analyzed. Gene enrichment analysis The public database Biological General Repository for Interaction Datasets (BioGRID, https://thebiogrid.org/ ) version 4.4.228 was used to analysis the protein interactions. GEPIA2.0 was used to obtain the top 100 IDH1 -correlated genes from all TCGA tumor and normal tissues. Then we conducted a pairwise gene-gene Pearson correlation analysis between IDH1 and the selected genes. Gene ontology (GO) and Kyoto encyclopedia of genes and genome (KEGG) enrichment analyses were used to investigate the underlying biological functions and signaling pathways affected by IDH1 in TCGA tumors. p-value < 0.05 was considered to be statistically significant. The source and generation of cell lines The U87 and U87 R132H cell lines was purchased from the American Type Culture Collection (ATCC). To generate control and IDH1 KD ( IDH1 KD -1 and IDH1 KD -2 ) U87 cells, the cells were transfected with control and IDH1 -siRNA lentiviral particles (GenePharma, China). IDH1 KD in figures represent the si IDH1-1 and si IDH1-2 ( 14 ). The sequence of siRNAs of IDH1 : IDH1 (human) siRNA-1#: 5’- GCATAATGTTGGCGTCAAA − 3’. IDH1 (human) siRNA-2#: 5’- GGCCCAAGCTATGAAATCA − 3’. Cell proliferation and migration Cell Proliferation For cell proliferation studies, 1×10 6 cells were seeded per 100 mm diameter dish. After 24–96 h, cells in a petri dish were counted using a hemocytometer under a light microscope. Cell migration Assay 3×10 5 cells were seeded in the 12 well plates. After 24 h, a linear wound was created by scratching the surface of the per well using a yellow pipette tip and incubating in RPMI without 10% FBS. The wounds were imaged, and their distance was measured using an inverted microscope. Western blot analysis The western blotting was performed as described previously ( 18 ). Briefly, 48h after transfection with IDH1 (human)-siRNAs, U87 cells protein were collected with the lysis buffer (RIPA, Solarbio). The total protein was isolated by polyacrylamide gel electrophoresis and then transferred to PVDF membrane from Millipore (Merk, Germany). After blocking with 5% skim milk powder (BioFroxx, Germany), membranes were incubated with the anti-IDH1 (1:1,000, CST, USA), anti-IDH1-R132H (1:1,000, Dianova, Germany), anti-GAPDH (1:50,000, proteintech, China) overnight at 4°C. After incubation with second antibodies, the bands of the proteins were stained with ECL reagent (Thermo, US) and were captured with imager (Baygene, China). X-ray radiation treatment Cells were treated with 0, 2, 4, 6, 8 Gy of X-ray by a linear accelerator (Clinac 2100EX, Varian Medical Systems). Colony formation assay was performed according to a previous protocol ( 18 ). Statistical analysis R 3.6.2 for Windows (R Project) was used to analyze the data, and Student’s t-test was applied to explore the differences between groups. Student t tests and one-way ANOVAs were used to determine inferential statistics. Quantitative data were presented as the mean ± SEM. Generally, all experiments repeated at least 3 times. P values < 0.05 was considered statistically significant. Results The different expression profiles of IDH1 in human pan-cancers In this study, we explored the role of human IDH1 (NM_001282386 for mRNA or NP_001269315 for protein) in tumors. We first analyzed the mRNA expression of IDH1 in different human neoplastic and non-neoplastic tissues through the TCGA database, and found that IDH1 was significantly highly expressed in many tumors, including esophageal carcinoma (ESCA), glioblastoma multiforme (GBM), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), stomach adenocarcinoma (STAD), thyroid carcinoma (THCA), uterine corpus endometrial carcinoma (UCEC) (p < 0.001 for the above tumors), and cervical endocervical adenocarcinoma and squamous cell carcinoma (CESC) (p < 0.05) (Fig. 1 A, 1 B). However, IDH1 was low expressed in some tumors, including breast invasive carcinoma (BRCA), cholangiocarcinoma (CHOL), kidney chromophobe (KICH), kidney renal clear cell carcinoma (KIRC), kidney renal papillary cell carcinoma (KIRP) (p < 0.001 for the above tumors), pheochromocytoma and paraganglioma (PCPG) (p < 0.01), and colon adenocarcinoma (COAD) (p < 0.05) (Fig. 1 A). The significance of IDH1 expression in clinical classification of 12 tumors was analyzed. At the same time, we found that the expression of IDH1 was significant only in the clinical grades of glioma, that is, the risk of pathological stage increased with the increase of IDH1 mRNA expression (Fig. 1 C). The expression level of IDH1 protein in tumors and corresponding normal tissues was studied by using the human protein map database (HPA). We found that the expression of IDH1 in kidney, skin, stomach, lung, brain and breast tumor tissues was higher than that in normal tissues, which was consistent with the results of mRNA expression analysis, suggesting that high expression of IDH1 may be a risk factor for LGG, GBM, LUAD, LUSC, and STAD (Fig. 1 D). The different expression profiles of IDH1 in human Glioma By analyzing CGGA database, we found that the expression of IDH1 was different in glioma with different pathological types and WHO grades (Fig. 2 A, 2 B). Moreover, the mRNA and protein levels of IDH1 wildtype U87 cell line and IDH1 mutant U87-R132H cell line were verified, and it was found that the total expression of IDH1 was significantly reduced in IDH1 -mutant glioma cell line (Fig. 2 C, 2 D). Then we verified the differential expression of IDH1 between IDH1 -wildtype and IDH1 -mutant gliomas in TCGA database. The result was consistent with above (Fig. 2 E). Then we analyzed the difference of OS and PFI between IDH1 -wildtype and IDH1 -mutant gliomas, and found both OS and PFI of IDH1 -wildtype glioma patients were significantly lower than those of IDH1 -mutant patients (Fig. 2 F). In addition, as shown in Table 1 , IDH1 expression levels are significant differences in WHO grade, IDH status, 1p/19q codeletion, primary therapy outcome, age, OS event, and histological type. Table 1 Clinicopathological characteristics of glioma patients with high- and low-IDH1 expression levels Characteristics Low expression of IDH1 High expression of IDH1 P value n 349 350 WHO grade, n (%) < 0.001 G2 156 (24.5%) 68 (10.7%) G3 129 (20.3%) 116 (18.2%) G4 18 (2.8%) 150 (23.5%) IDH status, n (%) < 0.001 WT 53 (7.7%) 193 (28%) Mut 291 (42.2%) 152 (22.1%) Gender, n (%) 0.342 Male 194 (27.8%) 207 (29.6%) Female 155 (22.2%) 143 (20.5%) 1p/19q codeletion, n (%) < 0.001 Non-codel 234 (33.8%) 286 (41.3%) Codel 114 (16.5%) 58 (8.4%) Primary therapy outcome, n (%) < 0.001 PD 54 (11.6%) 58 (12.5%) SD 94 (20.2%) 54 (11.6%) PR 46 (9.9%) 19 (4.1%) CR 103 (22.2%) 37 (8%) Age, n (%) 60 37 (5.3%) 106 (15.2%) <= 60 312 (44.6%) 244 (34.9%) OS event, n (%) < 0.001 Alive 266 (38.1%) 161 (23%) Dead 83 (11.9%) 189 (27%) Histological type, n (%) < 0.001 Astrocytoma 113 (16.2%) 83 (11.9%) Oligoastrocytoma 90 (12.9%) 45 (6.4%) Oligodendroglioma 128 (18.3%) 72 (10.3%) Glioblastoma 18 (2.6%) 150 (21.5%) The prognostic values of IDH1 across cancers In order to further explore the clinical value of IDH1 in human tumors, we determined the diagnostic and prognostic value of IDH1 expression level in 12 tumors with significantly aberrant expression by ROC and K-M analysis. As shown in the Fig. 3 , OS was significantly lower in gliomas with high IDH1 expression than in low IDH1 expression (p < 0.001), while no significant difference was observed in other tumors. Similarly, ROC curve analysis showed that IDH1 could accurately distinguish the adjacent tissues from glioma tissues. The AUC value was 0.982 in glioma, which indicated that it had the highest diagnostic value for glioma. The above clues all point out the important value of IDH1 in glioma. IDH1 mutation in various cancers In order to explore IDH1 mutations in various tumors, we analyzed its mutant status by using the cBioPortalTM platform based on TCGA data. Pan-cancer analysis suggested that IDH1 mutations were significantly higher in LGG than in other tumors. (Fig. 4 A). As shown in Fig. 4 B, we found that almost all IDH1-mutant types were missense mutation. Figure 4 C showed the mutation of arginine (Arg, R) at site 132 in the three-dimensional structure of IDH1 protein to histidine (His, H), cysteine (Cys, C), or glycine (Gly, G) changes. In addition, the association between IDH1 mutation and survival outcomes in glioma patients has been well established, which we will show below. The prognostic value of IDH1 in glioma We further analyzed the prognostic value of IDH1 in glioma under whether IDH1 mutation and different treatment conditions, and found that the prognosis was more significant in IDH1 -wildtype patients received chemoradiotherapy (Fig. 5 A- 5 H). In glioma patients, the prognosis was significant whether received radiotherapy or not (Fig. 5 A). However, for glioma patients whether received chemotherapy, the prognosis was only significant in patients received chemotherapy (Fig. 5 B). In IDH1 -wildtype glioma patients, the prognosis was similarly as mentioned above (Fig. 5 C- 5 E). However, in IDH1 -mutant glioma patients, the prognosis did not have significance (Fig. 5 F- 5 H). these may indicate that the upregulation of IDH1 was relevant to poor survival probability of glioma. Functional enrichment analysis of IDH1 in glioma We then enriched IDH1 -related genes in glioma. As shown in Fig. 6 A, genes that were positively or negatively correlated with IDH1 (false discovery rate, |FDR| < 0.01) were represented by dark red dots and dark green pots respectively. Besides, the top 50 positively and negatively correlated significant genes were shown in the heat map (Figs. 6 B, 6 C). As shown in Fig. 6 D, the interacting molecules with IDH1 were obtained from BioGRID web tool. Gene set enrichment analysis (GSEA) included GO analysis and KEGG pathway analysis. GO analysis indicated that IDH1 co-expressed genes were mainly involved in various metabolic processes, phosphatase complex, ubiquitin ligase complex, coated membrane, et al. (Figs. 6 E- 6 H). These genes were linked to the activities of receptors (Fig. 6 H). KEGG pathway analysis showed IDH1 and its co-expressed genes were enriched in citrate cycle, p53 signaling pathway, Notch signaling pathway, and DNA replication, et al. (Fig. 6 I). The single-cell analysis of IDH1 We further analyzed the IDH1 -associated malignant phenotypes in pan-cancers (Fig. 7 A). In glioma, wildtype IDH1 was positively correlated with metastasis, EMT, proliferation, invasion, and stemness, especially cell cycle (Fig. 7 B). However, wildtype IDH1 was negatively correlated with DNA damage (Fig. 7 B). We next analyzed the wildtype IDH1 in several tumors, and found wildtype IDH1 was highly expressed in glioma, GBM, LGG, AST, and ODG (Fig. 7 C). The effect of IDH1 on malignant phenotypes of glioma Finally, we introduced IDH1 -specific siRNAs to reduce IDH1 protein levels in U87 cell line (Fig. 8 A). The cell viability of U87 reduced when transfected with IDH1 -specific siRNAs (Fig. 8 B, 8 C). The migration ability of U87 also reduced when transfected with IDH1 -specific siRNAs (Fig. 8 D, 8 E). Radiotherapy sensitivity of U87 increased when transfected with IDH1 -specific siRNA (Fig. 8 F). Discussion The standard treatment of glioma including surgery followed by radiation and adjuvant chemotherapy did not obviously improve the prognosis of glioma patients ( 19 – 22 ). The effectiveness of these standard treatments varies based on factors like the glioma types and its molecular characteristics. For instance, glioma with certain genetic mutations ( 1p/19q co-deletion, MGMT promoter methylation, IDH1/2 mutations) may respond differently to these treatments compared to those without these mutations ( 20 ). This highlights the complexity of treating glioma and the need for more investigations. The distinct roles of wildtype and mutant IDH1 in glioma underscore the need for personalized treatment strategies. For instance, therapies targeting the mutant IDH1, such as vorasidenib and ivosidenib, have shown promise in clinical trials for IDH1 -mutant glioma patients ( 23 , 24 ). However, for IDH1 -wildtype patients, direct inhibitors of wildtype IDH1 are not widely reported. Recently, Zhang et al. found that wildtype IDH1 could be a potential diagnostic and prognostic biomarker for NSCLC as wildtype IDH1 maintains the NSCLC’s stemness and chemoresistance by activating serine biosynthetic pathway ( 14 ). The finding suggested that targeting downstream metabolic pathways of wildtype IDH1, such as the serine biosynthetic pathway, could offer new strategies for treating NSCLC, particularly in cases where tumors exhibit stemness characteristics and resistance to conventional therapies. While the study is specific to NSCLC, the mechanisms uncovered may have implications for understanding the role of wildtype IDH1 in other types of cancer, including glioma. In this article, we found that wildtype IDH1 mRNA and protein levels are both significantly elevated in IDH1 -nonmutational glioma. Besides, the clinical grades of glioma elevated accompanied by the increase of IDH1 expression. The expression of IDH1 was significantly correlated with poor prognosis of glioma patients. Cell function and signaling pathways enrichment analyses of IDH1 -associated genes were enriched in metabolic processes, phosphatase complex, TCA, DNA replication, p53 signaling pathway, Notch signaling pathway. IDH1 also correlated with various malignant phenotypes of glioma, and we verified that IDH1 promotes GBM cell viability, migration, and radioresistance in vitro. Mechanistically, wildtype IDH1 may regulate the metabolism to facilitate glioma progression. The present data provided evidence and clues to a better understanding of the tumor-promoting role of wildtype IDH1 and the underlying mechanisms in glioma progression. Wildtype IDH1 promotes the proliferation of colon cancer and renal cell carcinoma ( 15 , 16 ), the migration of primary GBM ( 17 ), the stemness of NSCLC ( 14 ), and the chemoresistance of melanoma, pancreatic cancer and NSCLC ( 14 , 25 , 26 ). However, the biological functions of wildtype IDH1 in tumor are still not well elucidated. Experts found that wildtype IDH1 is overexpressed in most primary GBM ( 27 ). Correspondingly, we also found that IDH1 mutation results the reduction of wildtype IDH1 in glioma in our study. We hypothesized that the better prognosis of IDH1 -mutant glioma patients may partly due to the reduction of wildtype IDH1. By using single-cell sequencing analysis, we found that cell cycle, metastasis, EMT, proliferation, invasion, stemness, and DNA damage are correlated with IDH1 expression. Consistently, we demonstrated that IDH1 promotes the GBM cell viability and migration, which demonstrated that wildtype IDH1 enhances the malignant behaviors of GBM cells. Moreover, wildtype IDH1 is negatively correlated with DNA damage. Previous studies reported that wildtype IDH1 was involved in tumor chemoresistance ( 14 , 25 , 26 ). However, the role of wildtype IDH1 in radioresistance has not been reported. Here, we firstly demonstrated that wildtype IDH1 promote radioresistance of U87. we speculated that wildtype IDH1 may be both involved in the chemotherapy or radiotherapy resistance in glioma and more evidence may be needed to demonstrate the potential role of IDH1. In conclusion, aberrantly high expression of wildtype IDH1 is positively correlated with poor prognosis of glioma. IDH1 tightly correlated with the proliferation, migration and radioresistance of glioma. Our findings provided evidence that wildtype IDH1 or its downstream metabolic pathways may be valuable targets for evaluating glioma prognosis and developing clinical therapy. Conclusion The high expression of wildtype IDH1 is positively correlated with poor prognosis of glioma. Besides, wildtype IDH1 is tightly correlated with malignant phenotypes of glioma. Downstream metabolic pathways of wildtype IDH1 and its interacting molecules may be targets for primary GBM therapy. Declarations Author Contribution Xiang Li and Yiran Tao wrote the main manuscript text. Wanqing Liu, Nan Hu, Zhou Jing, Zian Li, Xiao De, Lirui Dai, Yuqian Zheng, Zimin Shi and Weihua Hu prepared figures. Yuan Lyu, Junqi Li, Wulong Liang, Shaolong Zhou, Qiao Shan and Xudong Fu offered suggestions for revisions. Xinjun Wang provided the idea. All authors reviewed the manuscript. Data availability Statement The data used in the research can be found in TCGA ( http://portal.gdc.cancer.gov ), CGGA ( http://www.cgga.org.cn/ ), TIMER2.0 ( http://timer.cistrome.org/ ), GEPIA2.0 ( http://gepia2.cancer-pku.cn/ ), HPA ( https://www.proteinatlas.org/ ), cBioPortal ( https://www.cbioportal.org/ ), CancerSEA ( http://biocc.hrbmu.edu.cn/CancerSEA/ ), and BioGRID ( https://thebiogrid.org/ ). 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Neurosurgery, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Yiran","middleName":"","lastName":"Tao","suffix":""},{"id":283462854,"identity":"6a739f01-212a-4386-85c1-2a865fdd2a6a","order_by":2,"name":"Yuan Lyu","email":"","orcid":"","institution":"Medical Research Center, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Yuan","middleName":"","lastName":"Lyu","suffix":""},{"id":283462855,"identity":"997929df-9e34-47c4-978a-bf5d4306b8e3","order_by":3,"name":"Junqi Li","email":"","orcid":"","institution":"Medical Research Center, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Junqi","middleName":"","lastName":"Li","suffix":""},{"id":283462856,"identity":"f40d5504-d004-4465-8bbd-6bd7d09ae8c3","order_by":4,"name":"Wulong Liang","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Wulong","middleName":"","lastName":"Liang","suffix":""},{"id":283462857,"identity":"0423233b-1f69-4158-b839-ca94c706b02e","order_by":5,"name":"Wanqing Liu","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Wanqing","middleName":"","lastName":"Liu","suffix":""},{"id":283462858,"identity":"bdb7cf17-7581-4a1f-a483-3d1b1a082c14","order_by":6,"name":"Nan Hu","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Nan","middleName":"","lastName":"Hu","suffix":""},{"id":283462859,"identity":"dae3654f-6e1e-4deb-b580-2b373d2696b4","order_by":7,"name":"Zhou Jing","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Zhou","middleName":"","lastName":"Jing","suffix":""},{"id":283462860,"identity":"4f6aa9d7-2027-4b89-90a2-0f360e9f71d1","order_by":8,"name":"Zian Li","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Zian","middleName":"","lastName":"Li","suffix":""},{"id":283462861,"identity":"ff35e776-c56e-4c56-8668-934aa572bdca","order_by":9,"name":"Xiao De","email":"","orcid":"","institution":"Department of Neurosurgery, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Xiao","middleName":"","lastName":"De","suffix":""},{"id":283462862,"identity":"89b512f1-3a02-4fd2-9bd9-05df481051d9","order_by":10,"name":"Lirui Dai","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Lirui","middleName":"","lastName":"Dai","suffix":""},{"id":283462863,"identity":"1654f427-51ce-40ac-9d47-6e039abe1751","order_by":11,"name":"Yuqian Zheng","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Yuqian","middleName":"","lastName":"Zheng","suffix":""},{"id":283462864,"identity":"3943362d-dd6f-4e65-bcec-3a61b2bd4ac6","order_by":12,"name":"Zimin Shi","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Zimin","middleName":"","lastName":"Shi","suffix":""},{"id":283462865,"identity":"c90fbeb2-32b8-4cfe-aba3-1075a2e9c165","order_by":13,"name":"Weihua Hu","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Weihua","middleName":"","lastName":"Hu","suffix":""},{"id":283462866,"identity":"224da715-f0c4-4870-8cc0-eef2ed9ac1c9","order_by":14,"name":"Shaolong Zhou","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Shaolong","middleName":"","lastName":"Zhou","suffix":""},{"id":283462867,"identity":"a7ed39b0-77e1-4449-b207-296b06acb9dd","order_by":15,"name":"Qiao Shan","email":"","orcid":"","institution":"Department of Neurosurgery, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Qiao","middleName":"","lastName":"Shan","suffix":""},{"id":283462868,"identity":"a56d9d80-dcce-4998-811f-22fe505d05f8","order_by":16,"name":"Xudong Fu","email":"","orcid":"","institution":"Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":false,"prefix":"","firstName":"Xudong","middleName":"","lastName":"Fu","suffix":""},{"id":283462869,"identity":"fdc1bb03-8428-4fd2-b8c3-3f88b5521215","order_by":17,"name":"Xinjun Wang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAyUlEQVRIiWNgGAWjYNACHhsoTYKWNJK1MBwmQYvB8bOHX/PInLeXn5HA+OBtG4O8OUEtZ/LSLGfw3GZmnJHAbDi3jcFwZwMBLWYHcswMPvDcZmOWSGCT5m1jSDA4QEjL+TdmBgk853jYJBLYfxOn5UaO8YMPPAckeIC2MBOlxf7GGzPGGTzJBhI8D5sl55yTMNxASItkf47xZ94eO3v59uSDH96U2cgTtAUI2CQYe0A0YwOQkCCsHgiYPzD8IErhKBgFo2AUjFQAAOnMOWBrJpbHAAAAAElFTkSuQmCC","orcid":"","institution":"Department of Neurosurgery, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan","correspondingAuthor":true,"prefix":"","firstName":"Xinjun","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2024-03-08 13:16:38","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4043926/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4043926/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":53669229,"identity":"ddde59fe-263f-4844-8794-4a4df913f926","added_by":"auto","created_at":"2024-03-28 17:35:48","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":574476,"visible":true,"origin":"","legend":"\u003cp\u003eThe expression leves of the IDH1 in different tumors and pathological stages. (A) The expression status of the IDH1 gene in different tumors and matched normal tissues was analyzed through TIMER2. *P\u0026lt;0.05; **P\u0026lt;0.01; ***P\u0026lt;0.001. (B) The mRNA expression of DIH1 in glioma and corresponding normal tissues from TCGA. *P\u0026lt;0.05; **P\u0026lt;0.01; ***P\u0026lt;0.001. (C) The expression status of the IDH1 gene in different pathologic grades of tumors from TCGA. *P\u0026lt;0.05; **P\u0026lt;0.01; ***P\u0026lt;0.001. (D) the different expression of IDH1 between normal samples and tumors from HPA.\u003c/p\u003e","description":"","filename":"floatimage1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/5ff7db19d9bd759de1467b60.jpg"},{"id":53669231,"identity":"91819e2b-37d5-409f-ad9b-cc9c9ec8fac6","added_by":"auto","created_at":"2024-03-28 17:35:48","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":133416,"visible":true,"origin":"","legend":"\u003cp\u003eThe expression of IDH1 in different gliomas. (A-B) The expression of IDH1 in different pathological types and WHO grades of glioma from CGGA. (C) The qPCR of IDH1 in U87 and U87-R132H. (D) Western blot analysis of IDH1 and IDH1-R132H expression in U87 and U87-R132H cell lines, using GAPDH as a control protein. (E) Comparison of IDH1 expression between wildtype and mutant glioma, LGG, and GBM. (F) The OS and PFI of IDH1-mutant and IDH1-wildtype glioma patients.\u003c/p\u003e","description":"","filename":"floatimage2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/132c34939c6a14f0c035d21c.jpg"},{"id":53669230,"identity":"1a106139-d934-4654-8eb7-1a958a918b63","added_by":"auto","created_at":"2024-03-28 17:35:48","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":341466,"visible":true,"origin":"","legend":"\u003cp\u003eThe ROC and OS curves of IDH1 in different tumors.\u003c/p\u003e","description":"","filename":"floatimage3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/e1469009577027e83d70028f.jpg"},{"id":53669234,"identity":"b31f7411-efd0-4b94-9963-55642bea7391","added_by":"auto","created_at":"2024-03-28 17:35:48","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":171072,"visible":true,"origin":"","legend":"\u003cp\u003eThe mutation of IDH1. (A) The different alteration frequency of IDH1 in tumors. (B) The mutant types of IDH1. (C) The mutant sites of IDH1.\u003c/p\u003e","description":"","filename":"floatimage4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/718b0849bbc81c503ac7cb12.jpg"},{"id":53669228,"identity":"1e471cef-c3d5-4e54-afd9-0921d148afff","added_by":"auto","created_at":"2024-03-28 17:35:47","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":181917,"visible":true,"origin":"","legend":"\u003cp\u003eThe survival probability of IDH1 in glioma. (A) The survival probability of high and low IDH1 expression patients who receiving radiotherapy or not. (B) The survival probability of high and low IDH1 expression patients who receiving chemotherapy or not. (C) The survival probability of high and low wildtype IDH1 expression patients who receiving radio- and chemo-therapy or not. (D) The survival probability of high and low mutant IDH1 expression patients who receiving radio- and chemo-therapy or not.\u003c/p\u003e","description":"","filename":"floatimage5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/8b608088a645b6e1113af51a.jpg"},{"id":53669931,"identity":"ba296a71-4026-4fe2-ba3d-99e5c58065cf","added_by":"auto","created_at":"2024-03-28 17:43:48","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":531918,"visible":true,"origin":"","legend":"\u003cp\u003eFunctional enrichment analysis of IDH1 in glioma. (A) The top 100 positively and negatively IDH1-related significant genes in glioma. (B) The top 50 positively correlated significant genes of IDH1 in glioma. (C) The top 50 negatively correlated significant genes of IDH1 in glioma. (D) the interacting molecules with IDH1. (E-I) The Gene set enrichment analysis of IDH1.\u003c/p\u003e","description":"","filename":"floatimage6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/592f64ef519b9fbbdf09b3d2.jpg"},{"id":53669227,"identity":"184086c8-4a06-421f-8df1-fe6ff07677a9","added_by":"auto","created_at":"2024-03-28 17:35:47","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":230759,"visible":true,"origin":"","legend":"\u003cp\u003eThe single-cell analysis of IDH1. (A) The IDH1-associated malignant phenotypes in pan-cancers. (B) The IDH1-associated malignant phenotypes in glioma. (C) The expression of IDH1 in different tumor cells in single-cell level.\u003c/p\u003e","description":"","filename":"floatimage7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/859d3ff5489b255b6a856374.jpg"},{"id":53669232,"identity":"fe651c71-f5b6-4a04-9cc2-7dd1f9930656","added_by":"auto","created_at":"2024-03-28 17:35:48","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":286471,"visible":true,"origin":"","legend":"\u003cp\u003eThe effect of IDH1 on malignant phenotypes of glioma. (A) Western blot analysis of IDH1 expression in U87 cell lines, using GAPDH as a control protein. (B-C) The different cell viability of U87 after si-IDH1s. (C-D) The different migration ability of U87 after si-IDH1s. (E-F) The different redioresistance ability of U87 after si-IDH1.\u003c/p\u003e","description":"","filename":"floatimage8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/2ee1190ec77da42e79f33d35.jpg"},{"id":68163883,"identity":"10e2bda9-4194-4ee8-a0a9-5e6c1ebcc705","added_by":"auto","created_at":"2024-11-04 09:24:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2940256,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4043926/v1/000288fe-8911-49d0-89ec-95565deec786.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Unraveling the tumor-promoting role of wildtype Isocitrate dehydrogenase 1 (IDH1) in human gliomas","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn 2021 WHO classification of tumors of the central nervous system, the tumor that previously known as glioblastoma are now divided into two separate diagnoses based on the mutant status of \u003cem\u003eisocitrate dehydrogenase\u003c/em\u003e (\u003cem\u003eIDH\u003c/em\u003e), namely: glioblastoma (GBM), \u003cem\u003eIDH\u003c/em\u003e-wildtype, 4 grade; astrocytoma, \u003cem\u003eIDH\u003c/em\u003e-mutant, 4 grade (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). As a member of IDH family, isocitrate dehydrogenase 1 (IDH1) is an enzyme that plays a pivotal role in the tricarboxylic acid (TCA) cycle and redox regulation (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). The wildtype IDH1, encoded by the \u003cem\u003eIDH1\u003c/em\u003e gene located on chromosome 2q34, catalyzes the conversion of isocitrate to α-ketoglutarate (α-KG), simultaneously generating nicotinamide adenine dinucleotide phosphate (NADPH), in the cytoplasm and peroxisomes during cellular metabolism (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Compared with wildtype \u003cem\u003eIDH1\u003c/em\u003e, \u003cem\u003eIDH1\u003c/em\u003e mutations (primarily R132H variant) lead to a gain-of-function with the production of oncometabolite 2-hydroxyglutarate (2-HG) instead of α-KG, which disrupts normal metabolic processes and contributes to the initiation and progression of tumors (\u003cspan additionalcitationids=\"CR4 CR5 CR6\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). \u003cem\u003eIDH1\u003c/em\u003e mutations are found in approximately 80% grade Ⅱ-Ⅲ gliomas and second GBMs (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Besides, the presence of \u003cem\u003eIDH1\u003c/em\u003e mutations has been associated with better prognosis in glioma (\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). However, the cognition of wildtype IDH1 role in tumors is relatively little.\u003c/p\u003e \u003cp\u003eThe IDH1 wild type is almost exclusively enriched in primary GBM, which distinctly contrasts with the higher frequency of IDH1 mutations in secondary GBMs and other lower-grade gliomas (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). Recent advancements emphasized the multifaceted characteristics of wildtype IDH1, extending beyond normal metabolic functions. For instance, wildtype IDH1 maintains tumorigenesis of non-small cell lung cancer (NSCLC) and enhances gemcitabine chemoresistance by activating serine biosynthesis (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). Wildtype IDH1 are also tightly associated with tumor proliferation and migration (\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). To sum up, the tumor-promoting role of wildtype IDH1 has been gradually recognized.\u003c/p\u003e \u003cp\u003eIn this present study, we showed that wildtype IDH1 was aberrantly high expression in high-grade glioma tissues especially GBM. We assessed the prognostic value of wildtype IDH1 in glioma and the biological function in GBM cells. Enriched function and signal pathways upon \u003cem\u003eIDH1\u003c/em\u003e expression indicated that \u003cem\u003eIDH1\u003c/em\u003e may participate in the progress of various metabolic processes, phosphatase complex, ubiquitin ligase complex, TCA, p53 signaling pathway, Notch signaling pathway, and DNA replication. Single-cell analysis of IDH1 revealed that \u003cem\u003eIDH1\u003c/em\u003e involved in the progress of cell cycle, metastasis, EMT, proliferation, invasion, stemness, and DNA damage. Our data may provide new insights into the role of wildtype IDH1 in the progression of glioma and present a promising strategy for glioma therapy involving IDH1 blockade.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003eGene expression analysis\u003c/p\u003e \u003cp\u003eThe public databases TIMER2.0 (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://timer.cistrome.org/\u003c/span\u003e\u003cspan address=\"http://timer.cistrome.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) and Gene Expression Profiling Interactive Analysis 2 (GEPIA2.0, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://gepia2.cancer-pku.cn/\u003c/span\u003e\u003cspan address=\"http://gepia2.cancer-pku.cn/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) were respectively used to analyze the different expression profiles of \u003cem\u003eIDH1\u003c/em\u003e between pan-cancers and adjacent normal tissues, as well as the relationship between \u003cem\u003eIDH1\u003c/em\u003e expression and patients\u0026rsquo; pathological stages in TCGA cancers. Public database The Cancer Genome Atlas (TCGA, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://portal.gdc.cancer.gov\u003c/span\u003e\u003cspan address=\"https://portal.gdc.cancer.gov\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) was also used to assess the \u003cem\u003eIDH1\u003c/em\u003e expression in different tumor pathological stages across TCGA tumor types. The public database Chinese Glioma Genome Atlas (CGGA, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.cgga.org.cn/\u003c/span\u003e\u003cspan address=\"http://www.cgga.org.cn/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) was also used to assess the \u003cem\u003eIDH1\u003c/em\u003e expression in different pathological stages and WHO grades of glioma. Public database The Human Protein Atlas (HPA, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.proteinatlas.org/\u003c/span\u003e\u003cspan address=\"https://www.proteinatlas.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) was further used to confirm the intensity of IDH1 immunohistochemical staining in several tumor tissues, including renal cancer, skin cancer, and stomach cancer, lung cancer, glioma, and breast cancer.\u003c/p\u003e \u003cp\u003eSurvival analysis\u003c/p\u003e \u003cp\u003eThe expression of \u003cem\u003eIDH1\u003c/em\u003e on the patients\u0026rsquo; prognostic values, including overall survival (OS) and progression free interval (PFI), was obtained from GEPIA2.0. TCGA tumor patients were divided into the high-expression and low-expression cohorts based on the cut-off values (50% and 50%).\u003c/p\u003e \u003cp\u003eGenetic alteration analysis\u003c/p\u003e \u003cp\u003eThe public cBioPortal (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.cbioportal.org/\u003c/span\u003e\u003cspan address=\"https://www.cbioportal.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) was used to collect the alteration frequency, mutation type, mutation site information, and three-dimensional (3D) structure of IDH1.\u003c/p\u003e \u003cp\u003eSingle-cell RNA sequencing\u003c/p\u003e \u003cp\u003eAs a public single-cell sequencing database, CancerSEA (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://biocc.hrbmu.edu.cn/CancerSEA/\u003c/span\u003e\u003cspan address=\"http://biocc.hrbmu.edu.cn/CancerSEA/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) could provide various status of cancer cells in single-cell level. The correlation between \u003cem\u003eIDH1\u003c/em\u003e expression and various cancer cells malignant phenotypes was analyzed.\u003c/p\u003e \u003cp\u003eGene enrichment analysis\u003c/p\u003e \u003cp\u003eThe public database Biological General Repository for Interaction Datasets (BioGRID, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://thebiogrid.org/\u003c/span\u003e\u003cspan address=\"https://thebiogrid.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) version 4.4.228 was used to analysis the protein interactions. GEPIA2.0 was used to obtain the top 100 \u003cem\u003eIDH1\u003c/em\u003e-correlated genes from all TCGA tumor and normal tissues. Then we conducted a pairwise gene-gene Pearson correlation analysis between \u003cem\u003eIDH1\u003c/em\u003e and the selected genes. Gene ontology (GO) and Kyoto encyclopedia of genes and genome (KEGG) enrichment analyses were used to investigate the underlying biological functions and signaling pathways affected by \u003cem\u003eIDH1\u003c/em\u003e in TCGA tumors. p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered to be statistically significant.\u003c/p\u003e \u003cp\u003eThe source and generation of cell lines\u003c/p\u003e \u003cp\u003eThe U87 and U87 R132H cell lines was purchased from the American Type Culture Collection (ATCC). To generate control and \u003cem\u003eIDH1\u003c/em\u003e\u003csup\u003e\u003cem\u003eKD\u003c/em\u003e\u003c/sup\u003e (\u003cem\u003eIDH1\u003c/em\u003e\u003csup\u003e\u003cem\u003eKD\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e-1\u003c/em\u003e and \u003cem\u003eIDH1\u003c/em\u003e\u003csup\u003e\u003cem\u003eKD\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e-2\u003c/em\u003e) U87 cells, the cells were transfected with control and \u003cem\u003eIDH1\u003c/em\u003e-siRNA lentiviral particles (GenePharma, China). \u003cem\u003eIDH1\u003c/em\u003e\u003csup\u003e\u003cem\u003eKD\u003c/em\u003e\u003c/sup\u003e in figures represent the si \u003cem\u003eIDH1-1\u003c/em\u003e and si \u003cem\u003eIDH1-2\u003c/em\u003e (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe sequence of siRNAs of \u003cem\u003eIDH1\u003c/em\u003e:\u003c/p\u003e \u003cp\u003e \u003cem\u003eIDH1\u003c/em\u003e (human) siRNA-1#: 5\u0026rsquo;- GCATAATGTTGGCGTCAAA \u0026minus;\u0026thinsp;3\u0026rsquo;.\u003c/p\u003e \u003cp\u003e \u003cem\u003eIDH1\u003c/em\u003e (human) siRNA-2#: 5\u0026rsquo;- GGCCCAAGCTATGAAATCA \u0026minus;\u0026thinsp;3\u0026rsquo;.\u003c/p\u003e \u003cp\u003eCell proliferation and migration\u003c/p\u003e \u003cp\u003eCell Proliferation\u003c/p\u003e \u003cp\u003eFor cell proliferation studies, 1\u0026times;10\u003csup\u003e6\u003c/sup\u003e cells were seeded per 100 mm diameter dish. After 24\u0026ndash;96 h, cells in a petri dish were counted using a hemocytometer under a light microscope.\u003c/p\u003e \u003cp\u003eCell migration Assay\u003c/p\u003e \u003cp\u003e3\u0026times;10\u003csup\u003e5\u003c/sup\u003e cells were seeded in the 12 well plates. After 24 h, a linear wound was created by scratching the surface of the per well using a yellow pipette tip and incubating in RPMI without 10% FBS. The wounds were imaged, and their distance was measured using an inverted microscope.\u003c/p\u003e \u003cp\u003eWestern blot analysis\u003c/p\u003e \u003cp\u003eThe western blotting was performed as described previously (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). Briefly, 48h after transfection with \u003cem\u003eIDH1\u003c/em\u003e(human)-siRNAs, U87 cells protein were collected with the lysis buffer (RIPA, Solarbio). The total protein was isolated by polyacrylamide gel electrophoresis and then transferred to PVDF membrane from Millipore (Merk, Germany). After blocking with 5% skim milk powder (BioFroxx, Germany), membranes were incubated with the anti-IDH1 (1:1,000, CST, USA), anti-IDH1-R132H (1:1,000, Dianova, Germany), anti-GAPDH (1:50,000, proteintech, China) overnight at 4\u0026deg;C. After incubation with second antibodies, the bands of the proteins were stained with ECL reagent (Thermo, US) and were captured with imager (Baygene, China).\u003c/p\u003e \u003cp\u003eX-ray radiation treatment\u003c/p\u003e \u003cp\u003eCells were treated with 0, 2, 4, 6, 8 Gy of X-ray by a linear accelerator (Clinac 2100EX, Varian Medical Systems). Colony formation assay was performed according to a previous protocol (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e).\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eR 3.6.2 for Windows (R Project) was used to analyze the data, and Student\u0026rsquo;s t-test was applied to explore the differences between groups. Student t tests and one-way ANOVAs were used to determine inferential statistics. Quantitative data were presented as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SEM. Generally, all experiments repeated at least 3 times. \u003cem\u003eP\u003c/em\u003e values\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe different expression profiles of IDH1 in human pan-cancers\u003c/p\u003e \u003cp\u003eIn this study, we explored the role of human IDH1 (NM_001282386 for mRNA or NP_001269315 for protein) in tumors. We first analyzed the mRNA expression of \u003cem\u003eIDH1\u003c/em\u003e in different human neoplastic and non-neoplastic tissues through the TCGA database, and found that \u003cem\u003eIDH1\u003c/em\u003e was significantly highly expressed in many tumors, including esophageal carcinoma (ESCA), glioblastoma multiforme (GBM), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), stomach adenocarcinoma (STAD), thyroid carcinoma (THCA), uterine corpus endometrial carcinoma (UCEC) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 for the above tumors), and cervical endocervical adenocarcinoma and squamous cell carcinoma (CESC) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA, \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB). However, \u003cem\u003eIDH1\u003c/em\u003e was low expressed in some tumors, including breast invasive carcinoma (BRCA), cholangiocarcinoma (CHOL), kidney chromophobe (KICH), kidney renal clear cell carcinoma (KIRC), kidney renal papillary cell carcinoma (KIRP) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 for the above tumors), pheochromocytoma and paraganglioma (PCPG) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01), and colon adenocarcinoma (COAD) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA). The significance of \u003cem\u003eIDH1\u003c/em\u003e expression in clinical classification of 12 tumors was analyzed. At the same time, we found that the expression of IDH1 was significant only in the clinical grades of glioma, that is, the risk of pathological stage increased with the increase of \u003cem\u003eIDH1\u003c/em\u003e mRNA expression (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). The expression level of IDH1 protein in tumors and corresponding normal tissues was studied by using the human protein map database (HPA). We found that the expression of IDH1 in kidney, skin, stomach, lung, brain and breast tumor tissues was higher than that in normal tissues, which was consistent with the results of mRNA expression analysis, suggesting that high expression of IDH1 may be a risk factor for LGG, GBM, LUAD, LUSC, and STAD (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD).\u003c/p\u003e \u003cp\u003eThe different expression profiles of IDH1 in human Glioma\u003c/p\u003e \u003cp\u003eBy analyzing CGGA database, we found that the expression of \u003cem\u003eIDH1\u003c/em\u003e was different in glioma with different pathological types and WHO grades (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). Moreover, the mRNA and protein levels of IDH1 wildtype U87 cell line and IDH1 mutant U87-R132H cell line were verified, and it was found that the total expression of IDH1 was significantly reduced in \u003cem\u003eIDH1\u003c/em\u003e-mutant glioma cell line (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eD). Then we verified the differential expression of \u003cem\u003eIDH1\u003c/em\u003e between \u003cem\u003eIDH1\u003c/em\u003e-wildtype and \u003cem\u003eIDH1\u003c/em\u003e-mutant gliomas in TCGA database. The result was consistent with above (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE). Then we analyzed the difference of OS and PFI between \u003cem\u003eIDH1\u003c/em\u003e-wildtype and \u003cem\u003eIDH1\u003c/em\u003e-mutant gliomas, and found both OS and PFI of \u003cem\u003eIDH1\u003c/em\u003e-wildtype glioma patients were significantly lower than those of \u003cem\u003eIDH1\u003c/em\u003e-mutant patients (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eF). In addition, as shown in Table\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, \u003cem\u003eIDH1\u003c/em\u003e expression levels are significant differences in WHO grade, IDH status, 1p/19q codeletion, primary therapy outcome, age, OS event, and histological type.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eClinicopathological characteristics of glioma patients with high- and low-IDH1 expression levels\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLow expression of IDH1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHigh expression of IDH1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003en\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e349\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e350\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWHO grade, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eG2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e156 (24.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68 (10.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eG3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e129 (20.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e116 (18.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eG4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (2.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e150 (23.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIDH status, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e53 (7.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e193 (28%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMut\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e291 (42.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e152 (22.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.342\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e194 (27.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e207 (29.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e155 (22.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e143 (20.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1p/19q codeletion, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNon-codel\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e234 (33.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e286 (41.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCodel\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e114 (16.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e58 (8.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimary therapy outcome, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e54 (11.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e58 (12.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e94 (20.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54 (11.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e46 (9.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19 (4.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e103 (22.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37 (8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37 (5.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e106 (15.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;= 60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e312 (44.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e244 (34.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOS event, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAlive\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e266 (38.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e161 (23%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDead\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e83 (11.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e189 (27%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistological type, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAstrocytoma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e113 (16.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e83 (11.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOligoastrocytoma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90 (12.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45 (6.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOligodendroglioma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e128 (18.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72 (10.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGlioblastoma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (2.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e150 (21.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe prognostic values of IDH1 across cancers\u003c/p\u003e \u003cp\u003eIn order to further explore the clinical value of \u003cem\u003eIDH1\u003c/em\u003e in human tumors, we determined the diagnostic and prognostic value of \u003cem\u003eIDH1\u003c/em\u003e expression level in 12 tumors with significantly aberrant expression by ROC and K-M analysis. As shown in the Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, OS was significantly lower in gliomas with high \u003cem\u003eIDH1\u003c/em\u003e expression than in low \u003cem\u003eIDH1\u003c/em\u003e expression (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), while no significant difference was observed in other tumors. Similarly, ROC curve analysis showed that \u003cem\u003eIDH1\u003c/em\u003e could accurately distinguish the adjacent tissues from glioma tissues. The AUC value was 0.982 in glioma, which indicated that it had the highest diagnostic value for glioma. The above clues all point out the important value of \u003cem\u003eIDH1\u003c/em\u003e in glioma.\u003c/p\u003e \u003cp\u003eIDH1 mutation in various cancers\u003c/p\u003e \u003cp\u003eIn order to explore \u003cem\u003eIDH1\u003c/em\u003e mutations in various tumors, we analyzed its mutant status by using the cBioPortalTM platform based on TCGA data. Pan-cancer analysis suggested that \u003cem\u003eIDH1\u003c/em\u003e mutations were significantly higher in LGG than in other tumors. (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA). As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB, we found that almost all IDH1-mutant types were missense mutation. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC showed the mutation of arginine (Arg, R) at site 132 in the three-dimensional structure of IDH1 protein to histidine (His, H), cysteine (Cys, C), or glycine (Gly, G) changes. In addition, the association between \u003cem\u003eIDH1\u003c/em\u003e mutation and survival outcomes in glioma patients has been well established, which we will show below.\u003c/p\u003e \u003cp\u003eThe prognostic value of IDH1 in glioma\u003c/p\u003e \u003cp\u003eWe further analyzed the prognostic value of \u003cem\u003eIDH1\u003c/em\u003e in glioma under whether \u003cem\u003eIDH1\u003c/em\u003e mutation and different treatment conditions, and found that the prognosis was more significant in \u003cem\u003eIDH1\u003c/em\u003e-wildtype patients received chemoradiotherapy (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eA-\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eH). In glioma patients, the prognosis was significant whether received radiotherapy or not (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eA). However, for glioma patients whether received chemotherapy, the prognosis was only significant in patients received chemotherapy (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eB). In \u003cem\u003eIDH1\u003c/em\u003e-wildtype glioma patients, the prognosis was similarly as mentioned above (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eC-\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eE). However, in \u003cem\u003eIDH1\u003c/em\u003e-mutant glioma patients, the prognosis did not have significance (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eF-\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eH). these may indicate that the upregulation of \u003cem\u003eIDH1\u003c/em\u003e was relevant to poor survival probability of glioma.\u003c/p\u003e \u003cp\u003eFunctional enrichment analysis of IDH1 in glioma\u003c/p\u003e \u003cp\u003eWe then enriched \u003cem\u003eIDH1\u003c/em\u003e-related genes in glioma. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eA, genes that were positively or negatively correlated with \u003cem\u003eIDH1\u003c/em\u003e (false discovery rate, |FDR| \u0026lt; 0.01) were represented by dark red dots and dark green pots respectively. Besides, the top 50 positively and negatively correlated significant genes were shown in the heat map (Figs.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eB, \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eC). As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eD, the interacting molecules with IDH1 were obtained from BioGRID web tool.\u003c/p\u003e \u003cp\u003eGene set enrichment analysis (GSEA) included GO analysis and KEGG pathway analysis. GO analysis indicated that \u003cem\u003eIDH1\u003c/em\u003e co-expressed genes were mainly involved in various metabolic processes, phosphatase complex, ubiquitin ligase complex, coated membrane, et al. (Figs.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eE-\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eH). These genes were linked to the activities of receptors (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eH). KEGG pathway analysis showed \u003cem\u003eIDH1\u003c/em\u003e and its co-expressed genes were enriched in citrate cycle, p53 signaling pathway, Notch signaling pathway, and DNA replication, et al. (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eI).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe single-cell analysis of IDH1\u003c/p\u003e \u003cp\u003eWe further analyzed the \u003cem\u003eIDH1\u003c/em\u003e-associated malignant phenotypes in pan-cancers (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eA). In glioma, wildtype \u003cem\u003eIDH1\u003c/em\u003e was positively correlated with metastasis, EMT, proliferation, invasion, and stemness, especially cell cycle (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eB). However, wildtype \u003cem\u003eIDH1\u003c/em\u003e was negatively correlated with DNA damage (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eB). We next analyzed the wildtype \u003cem\u003eIDH1\u003c/em\u003e in several tumors, and found wildtype \u003cem\u003eIDH1\u003c/em\u003e was highly expressed in glioma, GBM, LGG, AST, and ODG (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eC).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe effect of IDH1 on malignant phenotypes of glioma\u003c/p\u003e \u003cp\u003eFinally, we introduced \u003cem\u003eIDH1\u003c/em\u003e-specific siRNAs to reduce IDH1 protein levels in U87 cell line (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eA). The cell viability of U87 reduced when transfected with \u003cem\u003eIDH1\u003c/em\u003e-specific siRNAs (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eB, \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eC). The migration ability of U87 also reduced when transfected with \u003cem\u003eIDH1\u003c/em\u003e-specific siRNAs (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eD, \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eE). Radiotherapy sensitivity of U87 increased when transfected with \u003cem\u003eIDH1\u003c/em\u003e-specific siRNA (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eF).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe standard treatment of glioma including surgery followed by radiation and adjuvant chemotherapy did not obviously improve the prognosis of glioma patients (\u003cspan additionalcitationids=\"CR20 CR21\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). The effectiveness of these standard treatments varies based on factors like the glioma types and its molecular characteristics. For instance, glioma with certain genetic mutations (\u003cem\u003e1p/19q\u003c/em\u003e co-deletion, \u003cem\u003eMGMT\u003c/em\u003e promoter methylation, \u003cem\u003eIDH1/2\u003c/em\u003e mutations) may respond differently to these treatments compared to those without these mutations (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e). This highlights the complexity of treating glioma and the need for more investigations.\u003c/p\u003e \u003cp\u003eThe distinct roles of wildtype and mutant \u003cem\u003eIDH1\u003c/em\u003e in glioma underscore the need for personalized treatment strategies. For instance, therapies targeting the mutant IDH1, such as vorasidenib and ivosidenib, have shown promise in clinical trials for \u003cem\u003eIDH1\u003c/em\u003e-mutant glioma patients (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). However, for \u003cem\u003eIDH1\u003c/em\u003e-wildtype patients, direct inhibitors of wildtype IDH1 are not widely reported. Recently, Zhang et al. found that wildtype IDH1 could be a potential diagnostic and prognostic biomarker for NSCLC as wildtype IDH1 maintains the NSCLC\u0026rsquo;s stemness and chemoresistance by activating serine biosynthetic pathway (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). The finding suggested that targeting downstream metabolic pathways of wildtype IDH1, such as the serine biosynthetic pathway, could offer new strategies for treating NSCLC, particularly in cases where tumors exhibit stemness characteristics and resistance to conventional therapies. While the study is specific to NSCLC, the mechanisms uncovered may have implications for understanding the role of wildtype IDH1 in other types of cancer, including glioma.\u003c/p\u003e \u003cp\u003eIn this article, we found that wildtype IDH1 mRNA and protein levels are both significantly elevated in \u003cem\u003eIDH1\u003c/em\u003e-nonmutational glioma. Besides, the clinical grades of glioma elevated accompanied by the increase of \u003cem\u003eIDH1\u003c/em\u003e expression. The expression of \u003cem\u003eIDH1\u003c/em\u003e was significantly correlated with poor prognosis of glioma patients. Cell function and signaling pathways enrichment analyses of \u003cem\u003eIDH1\u003c/em\u003e-associated genes were enriched in metabolic processes, phosphatase complex, TCA, DNA replication, p53 signaling pathway, Notch signaling pathway. \u003cem\u003eIDH1\u003c/em\u003e also correlated with various malignant phenotypes of glioma, and we verified that IDH1 promotes GBM cell viability, migration, and radioresistance in vitro. Mechanistically, wildtype IDH1 may regulate the metabolism to facilitate glioma progression. The present data provided evidence and clues to a better understanding of the tumor-promoting role of wildtype IDH1 and the underlying mechanisms in glioma progression.\u003c/p\u003e \u003cp\u003eWildtype IDH1 promotes the proliferation of colon cancer and renal cell carcinoma (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e), the migration of primary GBM (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e), the stemness of NSCLC (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e), and the chemoresistance of melanoma, pancreatic cancer and NSCLC (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). However, the biological functions of wildtype IDH1 in tumor are still not well elucidated. Experts found that wildtype \u003cem\u003eIDH1\u003c/em\u003e is overexpressed in most primary GBM (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e). Correspondingly, we also found that \u003cem\u003eIDH1\u003c/em\u003e mutation results the reduction of wildtype IDH1 in glioma in our study. We hypothesized that the better prognosis of \u003cem\u003eIDH1\u003c/em\u003e-mutant glioma patients may partly due to the reduction of wildtype IDH1. By using single-cell sequencing analysis, we found that cell cycle, metastasis, EMT, proliferation, invasion, stemness, and DNA damage are correlated with \u003cem\u003eIDH1\u003c/em\u003e expression. Consistently, we demonstrated that IDH1 promotes the GBM cell viability and migration, which demonstrated that wildtype IDH1 enhances the malignant behaviors of GBM cells. Moreover, wildtype IDH1 is negatively correlated with DNA damage. Previous studies reported that wildtype IDH1 was involved in tumor chemoresistance (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). However, the role of wildtype IDH1 in radioresistance has not been reported. Here, we firstly demonstrated that wildtype IDH1 promote radioresistance of U87. we speculated that wildtype IDH1 may be both involved in the chemotherapy or radiotherapy resistance in glioma and more evidence may be needed to demonstrate the potential role of IDH1.\u003c/p\u003e \u003cp\u003eIn conclusion, aberrantly high expression of wildtype IDH1 is positively correlated with poor prognosis of glioma. IDH1 tightly correlated with the proliferation, migration and radioresistance of glioma. Our findings provided evidence that wildtype IDH1 or its downstream metabolic pathways may be valuable targets for evaluating glioma prognosis and developing clinical therapy.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe high expression of wildtype IDH1 is positively correlated with poor prognosis of glioma. Besides, wildtype IDH1 is tightly correlated with malignant phenotypes of glioma. Downstream metabolic pathways of wildtype IDH1 and its interacting molecules may be targets for primary GBM therapy.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eXiang Li and Yiran Tao wrote the main manuscript text. Wanqing Liu, Nan Hu, Zhou Jing, Zian Li, Xiao De, Lirui Dai, Yuqian Zheng, Zimin Shi and Weihua Hu prepared figures. Yuan Lyu, Junqi Li, Wulong Liang, Shaolong Zhou, Qiao Shan and Xudong Fu offered suggestions for revisions. Xinjun Wang provided the idea. All authors reviewed the manuscript.\u003c/p\u003e\n\u003ch3\u003eData availability Statement\u003c/h3\u003e\n\u003cp\u003eThe data used in the research can be found in TCGA (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://portal.gdc.cancer.gov\u003c/span\u003e\u003cspan address=\"http://portal.gdc.cancer.gov\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), CGGA (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.cgga.org.cn/\u003c/span\u003e\u003cspan address=\"http://www.cgga.org.cn/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), TIMER2.0 (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://timer.cistrome.org/\u003c/span\u003e\u003cspan address=\"http://timer.cistrome.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), GEPIA2.0 (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://gepia2.cancer-pku.cn/\u003c/span\u003e\u003cspan address=\"http://gepia2.cancer-pku.cn/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), HPA (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.proteinatlas.org/\u003c/span\u003e\u003cspan address=\"https://www.proteinatlas.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), cBioPortal (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.cbioportal.org/\u003c/span\u003e\u003cspan address=\"https://www.cbioportal.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), CancerSEA (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://biocc.hrbmu.edu.cn/CancerSEA/\u003c/span\u003e\u003cspan address=\"http://biocc.hrbmu.edu.cn/CancerSEA/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), and BioGRID (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://thebiogrid.org/\u003c/span\u003e\u003cspan address=\"https://thebiogrid.org/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eLouis DN, Perry A, Reifenberger G, von Deimling A, Figarella-Branger D, Cavenee WK, et al. 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Vorasidenib in IDH1- or IDH2-Mutant Low-Grade Glioma. The New England journal of medicine. 2023;389(7):589-601.\u003c/li\u003e\n\u003cli\u003eZarei M, Hajihassani O, Hue JJ, Graor HJ, Loftus AW, Rathore M, et al. Wild-type IDH1 inhibition enhances chemotherapy response in melanoma. Journal of experimental \u0026amp; clinical cancer research : CR. 2022;41(1):283.\u003c/li\u003e\n\u003cli\u003eZarei M, Hajihassani O, Hue JJ, Graor HJ, Rothermel LD, Winter JM. Targeting wild-type IDH1 enhances chemosensitivity in pancreatic cancer. bioRxiv : the preprint server for biology. 2023.\u003c/li\u003e\n\u003cli\u003eCalvert AE, Chalastanis A, Wu Y, Hurley LA, Kouri FM, Bi Y, et al. Cancer-Associated IDH1 Promotes Growth and Resistance to Targeted Therapies in the Absence of Mutation. Cell reports. 2017;19(9):1858-73.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"wildtype IDH1, mutant IDH1, glioma, TCGA, prognosis, proliferation, migration, radioresistance","lastPublishedDoi":"10.21203/rs.3.rs-4043926/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4043926/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e \u003cem\u003eIsocitrate dehydrogenase 1\u003c/em\u003e (\u003cem\u003eIDH1\u003c/em\u003e) mutations are discovered in most grade Ⅱ gliomas (71%-78%), grade Ⅲ gliomas (62%-78%) and secondary glioblastomas (88%), and have received lots of attention in recent years. However, the tumor-promoting role of wildtype IDH1 still need to be further investigated. In this article, we found wildtype IDH1 mRNA and protein levels were both elevated in glioma by using bioinformatic analysis, Besides, \u003cem\u003eIDH1\u003c/em\u003e mutation reduced the expression of wildtype IDH1 in U87-R132H cell line. Furthermore, the expression of wildtype \u003cem\u003eIDH1\u003c/em\u003e also increased along with the increase of clinical grades of glioma. Cell function and signaling pathways enrichment analyses were enriched in metabolic processes, phosphatase complex, TCA, DNA replication, p53 signaling pathway, Notch signaling pathway, et al. Single-cell sequencing analysis revealed that high expression of wildtype \u003cem\u003eIDH1\u003c/em\u003e correlated with cell cycle, metastasis, EMT, proliferation, invasion, stemness, and DNA damage. Besides, wildtype IDH1 promoted GBM cell viability, migration, and radioresistance in vitro. Wildtype \u003cem\u003eIDH1\u003c/em\u003e was significantly relevant with diagnosis, prognosis, and survival probability of glioma patients. Therefore, wildtype IDH1 could be an underlying target for glioma therapy.\u003c/p\u003e","manuscriptTitle":"Unraveling the tumor-promoting role of wildtype Isocitrate dehydrogenase 1 (IDH1) in human gliomas","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-28 17:35:41","doi":"10.21203/rs.3.rs-4043926/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b174f401-d487-483a-9035-3454178993a4","owner":[],"postedDate":"March 28th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":29837627,"name":"Biological sciences/Cancer"},{"id":29837628,"name":"Biological sciences/Cancer/Cns cancer"}],"tags":[],"updatedAt":"2024-11-04T09:24:15+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-28 17:35:41","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4043926","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4043926","identity":"rs-4043926","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}