[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-342422-105":59,"doc-detail-342422-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","favipiravir-an-antiviral-drug-in-combination-with-tamoxifen-exerts-synergistic-effect-in-tamoxifenresistant-breast-cancer-cells-via-htert-inhibition","Favipiravir, an antiviral drug, in combination with tamoxifen exerts synergistic effect in tamoxifen‑resistant breast cancer cells via hTERT inhibition","","Tamoxifen-resistant breast cancer remains a major clinical barrier, linked to elevated human telomerase reverse transcriptase (hTERT). This study evaluates whether favipiravir, an RNA-dependent RNA polymerase (RdRp) inhibitor, can suppress hTERT and enhance tamoxifen activity. In TAMR-1 cells, combination treatment reduces cell proliferation synergistically (CI \u003C 1) and alters migration, apoptosis, and cell-cycle distribution. Effects correlate with decreased hTERT and CDK1 levels, supporting targeted disruption of hTERT-driven signaling.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/favipiravir-an-antiviral-drug-in-combination-with-tamoxifen-exerts-synergistic-effect-in-tamoxifenresistant-breast-cancer-cells-via-htert-inhibition/342422/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/favipiravir-an-antiviral-drug-in-combination-with-tamoxifen-exerts-synergistic-effect-in-tamoxifenresistant-breast-cancer-cells-via-htert-inhibition/342422.png","ImageObject",300,407,{"name":92,"@type":93},"Logic","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-09-24","2026-09-22",true,{"@type":102,"interactionType":103,"userInteractionCount":14},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"Why is tamoxifen resistance difficult to overcome in breast cancer?","Question",{"text":112,"@type":113},"Tamoxifen resistance persists as a significant barrier and is associated with increased hTERT expression, which supports tumor survival and proliferation.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How does favipiravir relate to hTERT inhibition in this study?",{"text":117,"@type":113},"Favipiravir inhibits RdRp of RNA viruses, and because hTERT shares structural similarity with RdRp, the study proposes that favipiravir may suppress hTERT to exert antitumor effects.",{"name":119,"@type":110,"acceptedAnswer":120},"What key effects were observed when favipiravir was combined with tamoxifen in TAMR-1 cells?",{"text":121,"@type":113},"The combination synergistically suppressed cell proliferation (CI \u003C 1) and produced significant changes in migration and apoptosis, alongside reduced hTERT and CDK1 levels and shifts in cell-cycle distribution.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},342422,1790245256,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":14,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":145},1099513958762,"https://ap-avatar.wpscdn.com/avatar/1000023916a998db790?x-image-process=image/resize,m_fixed,w_180,h_180&k=1784791008015729253","[www. nature.com/scientificreports](www. nature.com/scientificreports)  \nOPEN  \nFavipiravir, an antiviral drug, in combination with tamoxifen exerts synergistic effect in tamoxifen‑resistant breast cancer cells via hTERT inhibition  \nSally A. Fahim1*, YehiaA. ElZohairy2 & Rehab I. Moustafa 3,4  \nTamoxifen (TAM) is one of the most successful treatments for breast cancer; however, TAM resistance continues to be a significant barrier. TAM resistance has been reported to be associated with increased expression of human telomerase reverse transcriptase (hTERT). This enzyme shares structural similarity with RNA‑dependent RNA polymerase (RdRp) enzyme of RNA viruses, suggesting that RdRp inhibitors may also inhibit hTERT. Favipiravir (FAV) is an antiviral drug that inhibits RdRp of RNA viruses. Thus, we propose that FAV may also elicit an antitumor effect by suppressing hTERT.  \nThis study aimed to investigate the effect of FAV and TAM onTAM‑resistant breast cancer (TAMR‑1) . The cell viabilities were determined. The levels ofCDK1/ hTERT, in addition to regulators of hTERT‑ targeted signaling pathways were measured. Apoptosis, migration, and cell cycle distribution were also determined. Our data revealed that the combination ofTAM and FAV suppressed cell proliferation synergistically (CI \u003C 1) and resulted in a significant change in cell migration and apoptosis. Indeed, this was associated with reduced levels of hTERT and CDK1 and shift in the cell cycle distribution. Our findings suggest that the TAM/FAV combination exhibits synergistic effects against TAMR‑1 human breast cancer cells by targeting hTERT.  \nCancer is a complex disease marked by uncontrolled cell proliferation and the capacity to expand to other tissues. It is considered the second most likely cause of death and accounted for around 10 million deaths worldwide in 20191. Among all cancer types, breast cancer is the most common cancer in females, with an estimated 2.3 million new cases worldwide in 2020. Breast cancer is the fifth most prevalent cause of death due to cancer, with around 600,000 deaths worldwide in 20202. Patients being treated for cancer have a four-fold increased risk of viral infection and a ten-fold increased incidence of death3.  \nEndocrine therapy is crucial in breast cancer treatment. Appropriate treatment is implemented according to the type of hormone receptor expressed on the cell surface4. Tamoxifen (TAM) is considered the drug of choice for estrogen receptor-positive patients. TAM works by competing with estrogen for estrogen receptor binding in the breast tissue; thus, abolishing its consequent effects on tumor tissues5. Moreover, TAM is an inexpensive drug, which increased its prominent role. TAM has played a central role in saving many lives in addition to increasing the survival rate of patients with breast cancer around the globe6. Nevertheless, this therapy is limited by the development of TAM resistance and progression to metastasis. Around 20–30% of breast cancers are resistant to TAM after 3–5 years of treatment7; therefore, effective strategies are required to decrease TAM resistance. TAM resistance involves a number of signaling pathways, cell cycle regulators, growth factors, autophagy, and transcription factors that control estrogen receptor expression8–10. Interestingly, it has been reported that the suppression of telomerase rendered cells more sensitive to anticancer drugs regardless of their mode of action11–13. Telomerase is a ribonucleoprotein enzyme complex that prevents telomere shortening during cell division cycles.  \n1Department of Biochemistry, School of Pharmacy, Newgiza University (NGU), Newgiza, Km 22 Cairo-Alexandria Desert Road, 6th of October, P.O. Box 12577, Giza, Egypt. 2School of Pharmacy, Newgiza University (NGU), Newgiza, Km 22 Cairo-Alexandria Desert Road, P.O. Box 12577, Giza, Egypt. 3Microbial Biotechnology Department, Biotechnology Research Institute, National Research Centre, Dokki, Giza, Egypt. 4Microbi","cbCaiarcz3Onm1wW","https://ap.wps.com/l/cbCaiarcz3Onm1wW","pdf",4169069,14,"English","# Background\n## Tamoxifen resistance and hTERT\n# Study design and measurements\n## Cell viability and signaling markers\n## Apoptosis, migration, and cell cycle\n# Results\n## Synergistic suppression of proliferation (CI \u003C 1)\n## Reduced hTERT and CDK1 with altered cell cycle\n# Implications","[{\"question\":\"Why is tamoxifen resistance difficult to overcome in breast cancer?\",\"answer\":\"Tamoxifen resistance persists as a significant barrier and is associated with increased hTERT expression, which supports tumor survival and proliferation.\"},{\"question\":\"How does favipiravir relate to hTERT inhibition in this study?\",\"answer\":\"Favipiravir inhibits RdRp of RNA viruses, and because hTERT shares structural similarity with RdRp, the study proposes that favipiravir may suppress hTERT to exert antitumor effects.\"},{\"question\":\"What key effects were observed when favipiravir was combined with tamoxifen in TAMR-1 cells?\",\"answer\":\"The combination synergistically suppressed cell proliferation (CI \\u003c 1) and produced significant changes in migration and apoptosis, alongside reduced hTERT and CDK1 levels and shifts in cell-cycle distribution.\"}]","Favipiravir, an antiviral drug, in combination with tamoxifen exerts synergistic effect in tamoxifen‑resistant breast cancer cells via hTERT inhibition | PDF",1790046567,35]