Department of Digestive Diseases, the Second Affiliated Hospital of Chongqing Medical University, Yuzhong District, Chongqing, China.
Bosn J Basic Med Sci. 2012 Feb;12(1):4-9. doi: 10.17305/bjbms.2012.2523.
The insensitivity of hepatocellular carcinoma to chemotherapy is associated with alternation in tumor cell cycling. This current study was designed to investigate the impact of p15 silencing on the sensitivity of Human hepatocellular carcinoma HepG2 cells to cisplatin. HepG2/CDDP/1.6 and HepG2/CDDP/2.0 cells were induced by culture with increased doses of cisplatin and their sensitivities to cis-Diamine dichloroplatinum (CDDP) were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The impacts of p15 silencing on the cell cycling and P-gp expression were characterized by flow cytometry, RT-PCR and Western blot assays, respectively. Knockdown of p15 expression dramatically reduced the relative levels of p15 expression and the frequency of phase G1, promoting cell cycling. On the other hand, knockdown of p15 expression significantly up-regulated the expression of P-glycoprotein (P-gp) in HepG2/CDDP/2.0 cells, associated with the increased resistance of HepG2 cells to CDDP in vitro. In conclusion, the p15 may be a critical regulator of the development of CDDP resistance in HepG2 cells.
肝癌对化疗的不敏感性与肿瘤细胞周期的改变有关。本研究旨在探讨 p15 沉默对人肝癌 HepG2 细胞对顺铂敏感性的影响。用增加剂量的顺铂培养诱导 HepG2/CDDP/1.6 和 HepG2/CDDP/2.0 细胞，并通过 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐 (MTT) 测定其对顺二氨二氯铂 (CDDP) 的敏感性。通过流式细胞术、RT-PCR 和 Western blot 分析分别研究 p15 沉默对细胞周期和 P-糖蛋白表达的影响。p15 表达的敲低显著降低了 p15 表达的相对水平和 G1 期的频率，促进了细胞周期。另一方面，p15 表达的敲低显著上调了 HepG2/CDDP/2.0 细胞中 P-糖蛋白 (P-gp) 的表达，与 HepG2 细胞对 CDDP 的体外耐药性增加有关。综上所述，p15 可能是 HepG2 细胞中 CDDP 耐药发展的关键调节剂。
