Dysregulation of LincRNA-p21 in Gastric Adenocarcinoma

Background: Gastric cancer (GC) is the third leading cause of cancer-related death in the world and is often diagnosed at an advanced stage due to the lack of appropriate biomarkers. Long non-coding RNAs (lncRNAs) are considered promising biomarkers in various cancers such as GC. LincRNA-p21 is located upstream of the p21 (Cdkn1) tumor suppressor gene and regulates its expression. Despite reports of lincRNA-p21 deregulation in some cancers, its role in GC has not been well clarified. Materials &Methods: In this case-control study, total RNA was extracted from 33 matched pairs of tumor and non-tumor gastric samples and also gastric cancer cell lines (AGS and MKN45). Following cDNA synthesis, real-time PCR was performed. Data analysis was conducted by the GenEX5 and Statistical Program for Social Sciences (SPSS) software programs. Results Our results revealed a significant decrease in the expression of LncRNA-p21 in tumor samples compared to non-tumor samples (P = 0.009). The ability of LncRNA-p21expression level to discriminate between tumor and non-tumor samples was confirmed by ROC analysis. Additionally, lincRNA-p21 was found to be decreased in different grades of cancer. Conclusions The downregulation of lincRNA-p21 may leading to the loss of cell cycle control and increased tumorigenicity. Moreover, the observation that decreased expression of lincRNA-p21 occurs in different grades of malignancy highlights the potential of lincRNA-p21 as a valuable biomarker for the early diagnosis and prognosis of gastric cancer.