人结肠癌细胞系SP细胞microRNA表达谱的初步分析

 目的：探讨结肠癌侧群（SP）细胞在结肠癌多药耐药性中的作用及其microRNA生物标志。方法：结肠癌SP细胞的分选采用流式细胞术，细胞活力的测定采用MTT法，microRNA表达谱的检测采用microRNA芯片，microRNA表达的验证采用实时荧光定量PCR。结果：（1）HCT-15、HT-29及LoVo结肠癌细胞系中SP细胞的比例分别为16.75%、13.02%及9.52%。（2） 化疗药（5-氟尿嘧啶、草酸铂及阿霉素）对3种结肠癌细胞系SP细胞的 IC50均明显高于对非SP细胞的IC50（P<0.05）。（3）microRNA芯片检测表明miR-5000-3p、miR-5009-3p及miR-552在3种结肠癌细胞系的SP细胞中表达均上调，实时荧光定量PCR亦证实此结果。结论：miR-5000-3p、miR-5009-3p及miR-552在结肠癌细胞系的SP细胞中表达上调，有可能成为结肠癌SP细胞的潜在microRNA生物标志。

Priliminary analysis of microRNA expression profiles of side population cells in human colon cancer cell lines

AIM：To investigate the role of side population (SP) cells in multidrug resistance of colon cancer cells and microRNA biomarkers of SP cells in colon cancer cells. METHODS：SP cells in colon cancer cells were sorted by flow cytometry. The cell viability was measured by MTT method. MicroRNA expression profiles were detected by microRNA chip. MicroRNA expression was verified by real-time PCR. RESULTS：The ratios of SP cells in HCT-15, HT-29 and LoVo colon cancer cell lines were 16.75%, 13.02% and 9.52%, respectively. In all 3 colon cancer cell lines, IC50 of the antitumor drugs including 5-fluorouracil, oxaliplatin and adriamycin for the SP cells were significantly higher than those for non-SP cells (P<005). MicroRNA profiling showed that miR-5000-3p, miR-5009-3p and miR-552 were all up-regulated in the SP cells of all 3 colon cancer cell lines. This result was verified by real-time PCR. CONCLUSION：miR-5000-3p, miR-5009-3p and miR-552 are all up-regulated in the SP cells of colon cancer cell lines, and may be the potential microRNA biomarkers of SP cells in colon cancer.