胃癌SGC-7901细胞株侧群细胞分选及生物学特性的初步研究

Isolation and Identification of Side Population Cells from SGC-7901 Cell Strain

目的:分选胃癌细胞株中的侧群(side population,SP)细胞并初步研究其相关生物学特性。方法:选择人胃癌细胞株SGC-7901,以荧光染料Hoechst 33342染色,维拉帕米拮抗对照,应用流式细胞仪检测并分选出SP细胞和nonSP细胞。CCK-8法观察两组细胞体外增殖活性;体外耐药实验检测两组细胞对化疗药物5-FU的耐药存活率;无血清培养基培养观察肿瘤球形成能力;荧光定量PCR检测干细胞相关基因Musashi-1和CD44在两组细胞中的表达差异;裸鼠体内成瘤实验观察两组细胞体内成瘤能力。结果:胃癌细胞株SGC-7901中SP细胞的比例为2.8%,与nonSP细胞相比,SP细胞具有较强的体外增殖活性(P<0.05),对5-FU的耐药存活率明显高于nonSP细胞(P<0.05),在无血清培养基中能形成明显的肿瘤球,SP细胞中Musashi-1和CD44mRNA的相对表达量明显高于nonSP细胞(P<0.05),裸鼠体内成瘤实验表明,皮下注射2×103个SP细胞就能形成肿瘤,而2×104个nonSP细胞也不能形成肿瘤。结论:胃癌细胞株SGC-7901中存在数量极少的SP细胞,SP细胞具有肿瘤干细胞的相关生物学特性。

Objective： To separate SP cells from SGC-7901 and identify their biocharacteristics.Methods： SGC-7901 cells were sorted as SP cells and nonSP cells using flow cytometry after SGC-7901 cells were stained with Hoechst 33342.The proliferation of two group cells in vitro was detected using CCK-8;Drug resistance experiment was used to observe two group cell＇s resistance to 5-FU;The formation of tumor spheres was observed in serum-free culture media;The mRNA expression of Musashi-1 and CD44 was detected by real-time PCR;The tumorigeness in nude mouses was observed after nude mouses had been subcutaneously injected SP cells and nonSP cells for 8 weeks.Results： The proportion of SP cells in SGC-7901 is 2.8%;compared with nonSP cells,SP cells have stronger proliferation ability and higher resistance to 5-FU,SP cells could form obvious tumor spheres and have a higher expresssion of Musashi-1 and CD44,experiment in nude mouse demonstrates that 2×10^3 SP cells could form tumor after injecting into nude mouse subcutaneously while 2×10^4 nonSP cells could not form tunor.Conclusion：There is a small proportion of SP cells in SGC-7901,SP cells have relative biocharacteristics of tumor stem cells.