Flavopiridol inhibits FOXM1/NF-kB and KRAS/MAPK signaling and DNA repair mechanims and Sensitizes Triple-Negative Breast Cancer Cells to Doxorubicin the

Flavopiridol inhibits FOXM1/NF-kB and KRAS/MAPK signaling and DNA repair mechanims and Sensitizes Triple-Negative Breast Cancer Cells to Doxorubicin the | 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 Research Article Flavopiridol inhibits FOXM1/NF-kB and KRAS/MAPK signaling and DNA repair mechanims and Sensitizes Triple-Negative Breast Cancer Cells to Doxorubicin the Irem Metin, Ahsen Guler, Venhar Cınar, Bülent Ozpolat, Zuhal Hamurcu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9296085/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 Purpose Triple-negative breast cancer (TNBC) is an aggressive subtype characterized by frequent chemoresistance and poor clinical outcomes. Doxorubicin (DOX) is a standard therapeutic agent; however, acquired resistance limits its efficacy. Forkhead box M1 (FOXM1) and nuclear factor-κB (NF-κB) are key regulators of pro-survival signaling pathways implicated in TNBC progression and drug resistance. This study aimed to investigate whether flavopiridol enhances DOX sensitivity in TNBC cells by targeting the FOXM1–NF-κB signaling axis. Methods MDA-MB-231 and BT-549 TNBC cell lines were treated with DOX, flavopiridol, or their combination. Cell viability, clonogenic survival, apoptosis, and cell-cycle distribution were assessed. Protein expression levels of FOXM1, NF-κB, RAS/MAPK, and PARP were analyzed by Western blot. FOXM1 function was further evaluated באמצעות siRNA-mediated gene silencing. Results Combination treatment significantly reduced cell viability and clonogenic potential compared to single-agent treatments. Flavopiridol enhanced DOX-induced apoptosis and induced marked alterations in cell-cycle progression in both TNBC cell lines. At the molecular level, combination therapy suppressed FOXM1 expression and downregulated NF-κB and RAS/MAPK signaling pathways. FOXM1 silencing recapitulated these effects, confirming its central role in pro-survival signaling. Additionally, decreased PARP expression suggested impaired DNA repair capacity. Conclusion The FOXM1–NF-κB–RAS/MAPK axis plays a critical role in DOX resistance in TNBC. Targeting FOXM1 with flavopiridol enhances DOX sensitivity and represents a promising therapeutic strategy to overcome chemoresistance in aggressive TNBC. Triple-negative breast cancer Flavopiridol FOXM1 NF-κB RAS/MAPK Doxorubicin Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9296085","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":620153912,"identity":"33fb13cd-2a82-4abe-b69d-054eb85c92e0","order_by":0,"name":"Irem Metin","email":"","orcid":"","institution":"Gevher Nesibe Genome and Stem Cell Institute, , Erciyes University","correspondingAuthor":false,"prefix":"","firstName":"Irem","middleName":"","lastName":"Metin","suffix":""},{"id":620153913,"identity":"1a96ad93-034a-4990-b997-ea21063b7841","order_by":1,"name":"Ahsen Guler","email":"","orcid":"","institution":"Faculty of Medicine, Department and of Medical Biology, Fırat University,","correspondingAuthor":false,"prefix":"","firstName":"Ahsen","middleName":"","lastName":"Guler","suffix":""},{"id":620153914,"identity":"c7726c0e-ea7d-48d6-90ef-5d5a5082674b","order_by":2,"name":"Venhar Cınar","email":"","orcid":"","institution":"Faculty of Medicine, Department and of Medical Biology,Erciyes University","correspondingAuthor":false,"prefix":"","firstName":"Venhar","middleName":"","lastName":"Cınar","suffix":""},{"id":620153915,"identity":"cfad28cc-8e0a-4aa4-8cec-9c1c29a4072c","order_by":3,"name":"Bülent Ozpolat","email":"","orcid":"","institution":"Stephenson School of Biomedical Engineering, The University of Oklahoma,","correspondingAuthor":false,"prefix":"","firstName":"Bülent","middleName":"","lastName":"Ozpolat","suffix":""},{"id":620153916,"identity":"8994514a-e7e0-47e5-8566-44d09720bfdc","order_by":4,"name":"Zuhal Hamurcu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8klEQVRIiWNgGAWjYDACCSjNDyISIGwD4rRINqBoSSBCi8EBhBh+LfKzm59u5t1jl7j5eO/DDw/bbOwZ2Ju3STD+uIdTC+OcY2a3eZ4lJ247c9xYIrEtLbGB51iZBENCMU4tzBIJQC0HDiRuu5HGxpDYdjiBQSLHDKgFt8vYJNK/gbVsnv8MpOW/PYP8G/xaeIBmgrVskGADaTnA2CDBg1+LhERO2c05B5KNZ5xJAzryXHJiG09asUVCGm4t8jPSt914c8BOtr/9GOPHH2V29vzshzfe+GCDWwsqYGQD+g7EIFYDEPwhXukoGAWjYBSMHAAAwX9RAAqp5IsAAAAASUVORK5CYII=","orcid":"","institution":"Faculty of Medicine, Department and of Medical Biology,Erciyes University","correspondingAuthor":true,"prefix":"","firstName":"Zuhal","middleName":"","lastName":"Hamurcu","suffix":""}],"badges":[],"createdAt":"2026-04-01 21:38:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9296085/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9296085/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106961194,"identity":"97932daa-f901-48c1-8ce6-27bdeeec9035","added_by":"auto","created_at":"2026-04-15 09:24:40","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1186053,"visible":true,"origin":"","legend":"","description":"","filename":"MANUSCRIPT.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9296085/v1_covered_97f40da6-eba5-4812-b52c-138600afeb4e.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eFlavopiridol inhibits FOXM1/NF-kB and KRAS/MAPK signaling and DNA repair mechanims and Sensitizes Triple-Negative Breast Cancer Cells to Doxorubicin the\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"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":"Triple-negative breast cancer, Flavopiridol, FOXM1, NF-κB, RAS/MAPK, Doxorubicin","lastPublishedDoi":"10.21203/rs.3.rs-9296085/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9296085/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eTriple-negative breast cancer (TNBC) is an aggressive subtype characterized by frequent chemoresistance and poor clinical outcomes. Doxorubicin (DOX) is a standard therapeutic agent; however, acquired resistance limits its efficacy. Forkhead box M1 (FOXM1) and nuclear factor-κB (NF-κB) are key regulators of pro-survival signaling pathways implicated in TNBC progression and drug resistance. This study aimed to investigate whether flavopiridol enhances DOX sensitivity in TNBC cells by targeting the FOXM1\u0026ndash;NF-κB signaling axis.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eMDA-MB-231 and BT-549 TNBC cell lines were treated with DOX, flavopiridol, or their combination. Cell viability, clonogenic survival, apoptosis, and cell-cycle distribution were assessed. Protein expression levels of FOXM1, NF-κB, RAS/MAPK, and PARP were analyzed by Western blot. FOXM1 function was further evaluated באמצעות siRNA-mediated gene silencing.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eCombination treatment significantly reduced cell viability and clonogenic potential compared to single-agent treatments. Flavopiridol enhanced DOX-induced apoptosis and induced marked alterations in cell-cycle progression in both TNBC cell lines. At the molecular level, combination therapy suppressed FOXM1 expression and downregulated NF-κB and RAS/MAPK signaling pathways. FOXM1 silencing recapitulated these effects, confirming its central role in pro-survival signaling. Additionally, decreased PARP expression suggested impaired DNA repair capacity.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThe FOXM1\u0026ndash;NF-κB\u0026ndash;RAS/MAPK axis plays a critical role in DOX resistance in TNBC. Targeting FOXM1 with flavopiridol enhances DOX sensitivity and represents a promising therapeutic strategy to overcome chemoresistance in aggressive TNBC.\u003c/p\u003e","manuscriptTitle":"Flavopiridol inhibits FOXM1/NF-kB and KRAS/MAPK signaling and DNA repair mechanims and Sensitizes Triple-Negative Breast Cancer Cells to Doxorubicin the","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-10 16:06:05","doi":"10.21203/rs.3.rs-9296085/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":"21b04f33-f9ca-4123-acf4-23e5ca98183f","owner":[],"postedDate":"April 10th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-14T08:13:40+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-10 16:06:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9296085","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9296085","identity":"rs-9296085","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}