Duz, Mehmet BugrahanKaratas, Omer Faruk2026-03-262026-03-2620200301-48511573-497810.1007/s11033-020-05633-x2-s2.0-85087500339https://doi.org/10.1007/s11033-020-05633-xhttps://hdl.handle.net/20.500.14901/1768Karatas, Omer/0000-0002-0379-2088Resistance of laryngeal squamous cell carcinoma cells to traditional therapeutic regimens still remains to be a major reason for therapeutic failure in patients. In this study, we aimed at investigating the expression profiles of ATP-binding cassette (ABC) transporters and stem cell markers in 5-fluorouracil (5-FU) resistant laryngeal Hep-2 cells. We treated parental Hep-2 cells, with stepwise increased doses of 5-FU for almost 1 year to develop 5-FU resistant sub-lines with resistance against varying levels of 5-FU concentrations (4 sub-lines resistant to 1, 2, 4, and eightfold of 5-FU). Then, we measured the expression levels of 10 genes from ABC transporters family and 4 stem cell associated markers using quantitative reverse transcription polymerase chain reaction (qRT-PCR) to find out a potential relationship between these markers and chemoresistance. We found that stemness-associated markers had elevated expressions from the beginning of 5-FU resistance acquisition. Their expressions elevated stepwise while parental Hep-2 cells got resistance to higher doses of 5-FU. Expressions of tested ABC transporters (ABCA5, ABCB1, ABCB6, ABCC1, ABCC2, ABCC3, ABCC5, ABCC10 and ABCF2, and ABCG2) were also deregulated in 5-FU resistant Hep-2 cells. Although their expressions remained unaltered at the beginning of acquisition of resistance, expressions of ABC transporters except from ABCB6 increased significantly when cells became resistant to higher doses of 5-FU. Our results suggest that enrichment of cells with stemness characteristics and upregulation of ABC transporters might be amongst the crucial contributors of chemoresistance in laryngeal cancer cells.eninfo:eu-repo/semantics/closedAccessLaryngeal Squamous Cell Carcinoma5-FluorouracilABC TransportersStem Cell MarkersHep-2 CellsArticle