伊立替康与4-氨基吡啶联合应用对人结直肠癌细胞增殖作用的影响

目的 研究肿瘤化学治疗药物伊立替康(CPT-11)对人结直肠癌细胞株HT-29细胞的作用及对钾离子通道阻断剂4-氨基吡啶(4-AP)的影响,并探讨其抗HT-29细胞的可能机制.方法 CPT-11、4-AP以及两药联合应用对HT-29细胞增殖及细胞侵袭力的影响分别用MTT比色法和Transwell法检测.用流式细胞术膜联蛋白V-异硫氰酸荧光素碘化丙啶双染法检测上述两种药物对HT-29细胞凋亡的影响.用膜片钳方法 检测ATP敏感性钾电流(IKATP)的电流变化.结果 1.0～64.0μg/ml CPT-11可呈剂量依赖性和时间依赖性地抑制HT-29细胞增殖,而1.0 mmol/L的4-AP可使CPT-11的作用增强.16.0 μg/ml CPT-11和1.0 mmol/L 4-AP单独应用均可明显诱导HT-29凋亡、抑制HT-29细胞侵袭力,而两药联合应用能明显增加上述诱导凋亡和抑制侵袭力的作用.不同浓度CPT-11可剂量依赖性地降低细胞膜IKATP水平,呈剂量依赖负相关性.结论 CPT-11抑制人结直肠癌HT-29细胞增殖和侵袭力、诱导细胞凋亡等作用可被4-AP协同增强,可能机制与CPT-11抑制ATP敏感性钾通道开放有关.

The effects of irinotecan combined with 4-amion pyridine on the proliferation of human colorectal cancer cell

Objective To investigate the effects and potential mechanism of irinotecan (CPT-11), an antitumor drug, on human colorectal cancer cell line HT-29 and its impact on 4-amion pyridine (4-AP), a kalium ion channel blocker. Methods The effects of CPT-11, 4-AP and combination of two drugs on proliferation and invasion of HT-29 cells were measured by MTT and Transwell assay respectively. The impact of CPT-11 or 4-AP on cell apoptosis was determined by flow cytometry with Annexin-V and PI staining. The current of ATP sensitive potassium ion (IKATP) was measured by patch clamp. Results The CPT-11 could inhibit proliferation of HT-29 cells at dose from 1.0 to 64.0 μg/ml in dose-and time-dependent manners. Whereas the above effect was enhanced when CPT-11 combined with 4-AP (1.0 mmol/L). The administration of CPT-11 (16.0 μg/ml) or 4-AP (1.0 mmol/L) significantly induced the cell apoptosis and inhibited the invasion of HT-29 cells, furthermore, these effects could be enhanced by combination of two drugs. And the different concentrations of CPT-11 reduced the IKATP of cell membrane in negative dose-dependent manner. Conclusions The effects of CPT-11 on HT-29 cells, such as reducing proliferation and invasion as well as inducing the apoptosis, can be enhanced by 4-AP, which may be related to inhibition of ATP-sensitive potassium channels.