摘要目的 检测和分选胃癌细胞系中具有干细胞特性的侧群(SP)细胞,分析其生物学特性.方法 制备胃癌细胞株BGC-823悬液,经Hoechst 33342染色后,用荧光激活细胞分选技术分选出人胃癌SP和非SP(NSP)细胞,测定SP细胞亚群所占的比例.通过平板克隆实验检测SP细胞的克隆形成能力,无血清培养检测SP细胞的增殖能力.以不同浓度的氟尿嘧啶(5-Fu)处理BGC-823细胞后,检测SP细胞的耐药性,通过小鼠体内成瘤实验检测SP细胞的致瘤性.结果 流式细胞仪分析结果表明,BGC-823细胞中含少量SP细胞,占0.9％ ～2.1％.SP细胞组克隆形成数量为(217.67±15.50)个/孔,高于NSP细胞组[(147.00 ±17.58)个/孔,P＜0.01];SP细胞组克隆形成率为(72.56±5.17)％,高于NSP细胞组[(49.00±5.86)％,P＜0.01],表明SP细胞较NSP细胞有较强的克隆形成能力.经2.5、5、10和25 μg/ml的5-Fu作用36 h后,SP细胞所占比例分别为12.9％、9.9％、4.0％和2.1％,化疗药物对SP细胞的抑制作用随着药物浓度的递增而加强.体内成瘤实验显示,SP细胞组瘤体质量为(0.176 ±0.034)g,NSP细胞组瘤体质量仅为(0.045 ±0.046)g,两组细胞所致瘤体质量差异有统计学意义(P＜0.05).结论 人胃癌细胞BGC-823中存在具有干细胞特性的SP细胞,进一步开展对人胃癌干细胞生物学特性的研究,将可能提示胃癌新的诊断和治疗途径.

abstractsObjective Isolate and characterize the side population (SP) cells with potency of stem cells from human gastric carcinoma cell line BGC-823.Methods SP and non-SP cells were sorted from BGC-823 cells by fluorescence-activated cell sorting (FACS) using Hoechst33342 staining.The tumorigenic ability of the SP cells was assessed by in vivo transplantation into non-obese diabetic/severe combined immunodeficiency mice.Results SP cells were isolated from BGC-823 cells in a proportion of 0.9％ to 2.1％ with respect to the whole cell population.The colony formation assay showed that the colony formation rate of the SP cells was significantly higher than that of the non-SP cells (72.56％ vs.49.00％,P ＜ 0.01 ).The drug sensitivity test showed that the SP cells showed stronger drug resistance to 5-Fu than the non-SP cells.The in vivo transplantation of SP cells in mice showed that the tumor weight was (0.176 ± 0.034) g,significantly higher than that of non-SP cells (0.045 ± 0.046) g ( P ＜ 0.01 ).Conclusions The results of this study indicate the existence of cancer stem-like SP cells in the human gastric cancer line BGC-823 cells. Further characterization of this SP cell population may provide new insights for diagnosis and treatment of gastric cancer.