人宫颈癌侧群细胞的分选及其生物学特性的研究

摘要

Objective To isolate side population (SP) cells from human cervical cancer cells and to determine the characteristics of cancer stem cells, so as to investigate the feasibility of starting research on cervical cancer stem cells from the SP cells. Methods The human cervical cancer cells were obtained from fresh human cervical cancer tissue of 40 patients who were diagnosed as cervical cancer. Flow cytometry and Hoechst 33342 dye efflux assay were used to isolate SP cells and NSP cells from the cervical cancer cells. The proliferation and differentiation of the two sub - population cells were observed. The two sub - population cells were injected into nude mice subcutaneously to observe their tumorigenesis ability. The inhibition rates of SP and NSP cells were assessed after treatment with chemotherapy drugs ( cisplatin) to evaluate the resistance. Results The proportion of SP cells excluding Hoechst 33342 dye in the human cervical cancer cells was 2. 04% ±0. 93% , and the proportion of the SP cells was decreased with the the degree of reduction of differentiation(P <0. 05). Cell growth curve indicated that proliferative capacity of the SP cells was better than the NSP cells (P<0. 05). The SP cells demonstrated stronger tumorigenesis ability in nude mice. As few as 1 x 103 SP cells could give rise to new tumors in xenotransplantation, with a tumorigenesis ability 100 times as high as that of the NSP cells. The time of tumor formation was significantly reduced. After treatment with different concentrations of chemotherapy drugs (cisplatin) for 24h, the SP cells had significantly lower inhibition rate than the NSP cells ( P < 0. 05 ). Conclusion Human cervical cancer cells contains a small subpopulation of cells excluding Hoechst 33342 dye. The more poorly the cell line differentiated, the fewer the proportion it contained. The SP cells has better proliferative capacity in vitro and stronger tumorigenicity than the NSP cells, with strongly resistant to chemotherapy drugs. The SP cells have the characteristics of cancer stem cells. So it can be applied to the cervical cancer stem cell research.%目的 通过人宫颈癌细胞中侧群细胞的富集、分离和鉴定,确定其肿瘤干细胞特性,探讨以侧群细胞作为宫颈癌干细胞研究切入点的可行性.方法 收集40例宫颈癌患者的手术标本,通过原代培养、流式细胞荧光激活分选法将宫颈癌细胞分为侧群( side population,SP)细胞和非侧群细胞(non-side population,NSP)2个亚群,观察2组细胞的增生和分化能力,并进行裸鼠接种以观察其成瘤能力,化疗药物顺铂以不同浓度作用于SP细胞和NSP细胞后计算细胞抑制率,以评价2组细胞对化疗药物的耐受性.结果 人宫颈癌细胞中侧群细胞的比例约为2.04％±0.93％,侧群细胞的比例随分化程度的降低而下降(P＜0.05).细胞生长曲线(MTT法)显示,SP细胞的体外增生能力明显强于NSP细胞(P＜0.05)；行裸鼠接种时,SP细胞表现出较强的致瘤性,只需1×103个即可致瘤,其致瘤能力是NSP细胞的100倍,且成瘤时间显著缩短；化疗药物顺铂以不同浓度分别作用于SP细胞与NSP细胞24h后,SP细胞的抑制率明显低于NSP细胞(P＜0.05).结论 人宫颈癌细胞中存在外排Hoechst 33342荧光染料的SP细胞,分化越差的肿瘤细胞其SP细胞比例越低.宫颈癌SP细胞体外增生能力和裸鼠成瘤能力均强于NSP细胞,对化疗药物具有较强的耐受性,具备肿瘤干细胞的特性,可作为宫颈癌干细胞研究的切入点.