肝癌细胞系HepG2中侧群细胞的生物学特性观察

Observation of the Biological Characteristics of Side Population Cells Sorted from Hepatocellular Carcinoma HepG2 Cell Line

目的:分选肝癌细胞系HepG2中侧群细胞并观察其生物学特性。方法:利用流式细胞荧光激活分选技术分选肝癌细胞系HepG2中的侧群细胞(SP)。实验细胞分为SP细胞、非侧群细胞(NSP)以及未分选细胞(Total组)3群,分别采用细胞生长曲线法比较3群细胞的增殖能力,平板克隆形成实验和裸鼠成瘤实验观察其体内外成瘤能力。结果:HepG2细胞中分选出的SP细胞比例为(3.1±0.2)%,细胞生长曲线表明SP细胞的增殖速度快于NSP细胞和未分选细胞(P<0.05),SP、NSP和未分选细胞软琼脂平板克隆形成率分别为66%、16%和32%;裸鼠体内成瘤率分别为100%(10/10)、30%(3/10)和70%(7/10),同时3组肿瘤平均质量分别为0.728g、0.185g及0.452g(P<0.05)。结论:肝癌细胞系HepG2中SP细胞的成瘤性和增殖能力强于非SP细胞和未分选细胞,表明SP细胞在肝癌的发生、发展中具有重要作用。

Objective To isolate side population （SP） cells from HepG2 cell line and observe their biological characteristics. Methods Flow cytometry and Hoechst 33342 dye effiux assay were used to isolate SP cells from HepG2 cell line of human hepatocellular carcinoma. This experiment was designed for three groups： SP cells group, non-SP cells group and total cells group without sorting. The cell proliferation was determined by MTT assay. Then the tumorigenicity of three subpopulations were observed by soft agar cloning method and inoculation in nude mice. Results Side population cells were isolated from HepG2 cell line with a proportion of （3.1±0.2）%. Cell growth curve indicated that the proliferative capacity of the side population cells was better than those of the non-SP cells and the total cells without sorting. Colony form ation assay showed that the colony- forming efficiency of the SP cells was higher than those of the non-SP cells and the total cells （66 % vs 16 % vs 32 %）. Tumorigenicity in vivo of the SP cells was higher than those of the non-SP cells and the total cells （100% vs30% vs70%）, and the tumor weight was respectively 0.728 g vs 0.185 g vs 0.452 g（P〈0.05）. Conclusion The SP cells sorted from HepG2 cell line of human hepatocellular carcinoma showed higher tumorigenicity and proliferative capacity, indicating that SP cells play an important role in the development and progression of hepatooellular carcinoma.