研究SIRT1沉默减少胆管癌细胞5-氟尿嘧啶（5-FU）耐药性的机制以及FOXO1 / Rab7自噬通路在介导此效应中的作用。采用50、100、150和200μg / mL 5-FU处理人类胆管癌HCCC-9810细胞构建5-FU耐药细胞模型，使用免疫荧光分析、Western blotting和RT-qPCR检测SIRT1、FOXO1和Rab7的表达，并使用Western blotting检测自噬相关蛋白（Beclin1、LC3和p62）的表达水平。用SIRT1 siRNA转染5-Fu耐药细胞，并使用CCK-8分析和划痕愈合实验评估细胞的5-Fu耐药性和迁移能力的变化。使用RT-qPCR和Western blotting检测SIRT1、FOXO1、Rab7、Beclin1、LC3和P62的mRNA水平和蛋白表达水平变化。采用50、100、150和200μg / mL 5-FU处理均能抑制HCCC-9810细胞的增殖。免疫荧光分析显示5-FU耐药的HCC-9810细胞中SIRT1表达显著增强，Western blotting也显示SIRT1、Rab7、P62、FOXO1和Beclin1的蛋白表达水平显著上调（P <0.001），LC3II / LC3I比值在细胞中增加（P <0.001）。SIRT1、Rab7和FOXO1的mRNA水平在5-Fu耐药细胞中也上调（P <0.05）。SIRT1沉默明显减轻了HCCC-9810细胞的5-FU耐药性和迁移能力，并显著降低了SIRT1、Rab7、P62、FOXO1和Beclin1的蛋白表达水平以及LC3II / LC3I比值（P <0.001）。SIRT1沉默后，5-FU耐药的HCC-9810细胞中FOXO1和Rab7的mRNA水平显著降低（P <0.05）。沉默SIRT1通过抑制FOXO1 / Rab7自噬通路的激活来减轻HCC-9810细胞对5-FU的耐药性。

To investigate the mechanism by which SIRT1 silencing reduces 5-fluorouracil (5-FU) resistance of cholangiocarcinoma cells and the role of FOXO1/Rab7 autophagy pathway in mediating this effect.Human cholangiocarcinoma HCCC-9810 cells were treated with 50, 100, 150, and 200 μg/mL 5-FU to construct a 5-FU-resistant cell model, whose expressions of SIRT1, FOXO1 and Rab7 were detected with immunofluorescence assay, Western blotting and RTqPCR, and the expression levels of autophagy related proteins (Beclin1, LC3, and p62) were detected with Western blotting. The 5-FU resistant cells were transfected with a SIRT1 siRNA, and the changes in 5-Fu resistance and migration ability of the cells were evaluated using CCK-8 assay and wound healing assay; The changes in FOXO1 and Rab7 mRNA levels and protein expressions of SIRT1, FOXO1, Rab7, Beclin1, LC3 and P62 were detected with RT-qPCR and Western blotting.Treatments with 5-FU at 50, 100, 150, and 200 μg/mL all inhibited the proliferation of HCCC-9810 cells. Immunofluorescence assay revealed significantly enhanced SIRT1 expression in 5-FU-resistant HCC-9810 cells, and Western blotting also showed significantly up-regulated protein expressions of SIRT1, Rab7, P62, FOXO1 and Beclin 1 (P < 0.001) and an increased LC3II/LC3I ratio in the cells (P < 0.001). The mRNA levels of SIRT1, Rab7 and FOXO1 were also up-regulated in 5-Fu-resistant cells (P < 0.05). SIRT1 silencing significantly attenuated 5-FU resistance and migration ability of HCCC-9810 cells, and obviously decreased the protein expressions of SIRT1, Rab7, P62, FOXO1 and Beclin1 and the LC3II/LC3I ratio as well (P < 0.001). FOXO1 and Rab7 mRNA levels were significantly decreased in 5-FU-resistant HCC-9810 cells after SIRT1 silencing (P < 0.05).Silencing SIRT1 attenuates 5-FU resistance in HCC-9810 cells by inhibiting the activation of the FOXO1/Rab7 autophagy pathway.