miR-433通过靶向YAP1抑制结直肠癌HCT-116细胞的干细胞特性并提高其5-FU敏感性OA

Objective:To investigate the role of microRNA-433(miR-433)in regulating stemness and chemoresistance in colorectal cancer(CRC)cells and to elucidate the underlying molecular regulatory mechanisms.Methods:A 5-FU-resistant HCT-116 cell line was established.The expression levels of miR-433 and stemness markers(SOX2,OCT4,and Nanog)were assessed using RT-qPCR and WB assay.The interaction between miR-433 and its target gene,YAP1,as well as the effect on the subcellular localization of YAP1,were verified through dual-luciferase reporter assays,immunofluorescence staining,and nuclear-cytoplasmic fractionation.Rescue experiments were conducted to confirm the functional role of the miR-433/YAP1 axis.The sensitivity of cells to 5-FU was evaluated using the CCK-8 assay.Results:Compared with parental cells,the expression of miR-433 was significantly downregulated in 5-FU-resistant HCT-116 cells(P<0.05),whereas the expression of stemness markers(SOX2,OCT4,and Nanog)was upregulated(P<0.05).Overexpression of miR-433 suppressed the expression of stemness markers,directly targeted YAP1,and inhibited the nuclear translocation of YAP1(P<0.05).Restoration of the expression of YAP1 partially reversed the inhibitory effect of miR-433 on stemness molecules(P<0.05).Functionally,upregulation of miR-433 significantly enhanced the sensitivity of CRC cells to 5-FU;this effect was attenuated by the re-expression of YAP1(P<0.05).Conclusion:miR-433 suppresses the stem-like molecular phenotype of colorectal cancer cells and enhances sensitivity to chemotherapeutic agents by directly targeting the YAP1 pathway.The miR-433/YAP1 axis may serve as a potential novel therapeutic target for overcoming chemoresistance in CRC.