奥曲肽逆转肝癌细胞多药耐药机制的初步研究

目的：探讨生长抑素类似物奥曲肽(octreotide)逆转肝癌细胞多药耐药，增加肝癌细胞对化疗药物敏感性的机制。方法：应用MTT法分析肝癌细胞对化疗药物的敏感性；用RT—PCR、流式细胞术检测肝癌细胞多药耐药基因MDR1、MRP2 mRNA蛋白质的表达。结果：奥曲肽联合化疗药物可以显著降低各化疗药物的IC50。肝癌原代培养细胞有SSTR2、SSTR3、MDR1、MRP2的表达，奥曲肽可以显著降低肝癌细胞表面MDR1、MRP2的表达。结论：奥曲肽可以与肝癌细胞表面的SSTR结合，降低肝癌细胞表面MDR1、MRP2的表达，从而使细胞内细胞毒药物浓度增加，逆转肝癌细胞多药耐药。

Mechanism of octreotide reversing multidrug resistance in hepatoma cells

Objective: To investigate the mechanism of octreotide reversing multidrug resistance and the effect of octreotide on chemosensitizing hepatoma cells. Methods: The expression of the MDR1, MRP2 mRNA and protein were analyzed by RT-PCR and flow cytometer respectively. The cytotoxic effects of epirubincin, carboplatin, hydroxyl-camptothecin and 5-fluorouracil were analyzed by MTT assay. Results: The 50% inhibitory concentration of cytotoxic agents were significantly reduced after octreotide treatment. RT-PCR and flow cytometer showed a significantly reduced expression of P-glycoprotein and MRP2 on the cell surface of hepatoma primary culture cells after octreotide treatment. Conclusions: Octreotide can chemosensitize hepatoma cells and chemosensitization can be achieved by inhibiting the expression of the MDR1?MRP2 gene on the surface of hepatoma cells.