人胆囊癌细胞系GBC-SD侧群细胞致瘤特性的实验研究

目的 研究人胆囊癌细胞系GBC-SD侧群细胞(side population cells，SP)的致瘤特性。方法 利用流式细胞术从GBC-SD中分选SP、非SP细胞(non-SP)，分别进行软琼脂克隆形成实验和非肥胖性糖尿病联合免疫缺陷(NOD/SCID)小鼠的移植瘤形成实验。通过流式细胞术检测5例人胆囊癌组织中SP细胞的比例。结果人胆囊癌细胞系GBC-SD中存在SP细胞，其比例约为0.87％；SP细胞的克隆形成率高于non-SP细胞（14.74％±3.53％比5.17％±1.05％，t=2.75，P＜0.05）。NOD/SCID小鼠移植瘤实验表明，5×103个SP细胞可成瘤(4/7)，而non-SP细胞成瘤则需要1×105个细胞(1/7)，且来源于SP细胞亚群的NOD/SCID小鼠移植瘤中存在SP、non-SP细胞。SP细胞存在于人胆囊癌组织中，其范围为0.27％～2.3％。结论来源于GBC-SD的SP细胞亚群具有类似肿瘤十细胞的高致瘤性。

The tumorigenic property of side population cells in a human gallbladder carcinoma cell line GBC-SD

Objective To explore the tumor igenic property of side population cells (SP) from human gallbladder carcinoma cell line GBC-SD. Methods SP and non-SP cells were isolated from GBC-SD staining with Hoechst33342 dye by fluorescence-activated cell sorting (FACS). The soft agar clonal assay and xenograft assay were performed to characterize tumorigenic property of side population cells in vitro and in vivo, respectively. The percentage of SP cells was analyzed by FACS in 5 hu man gallbladder carcinoma specimens. Results The percentage of SP cells accounted for approximately 0.87 ％ of GBC-SD cells. The clone-formed rates of SP was more frequent than that of non-SP cells (14.74％ ± 3.53％ vs 5.17％ ± 1.05％), there was statistically significant difference (t =2.75,P＜0. 05). SP cells could generate tumors with as few as 5 × 103 cells (four of seven animals), whereas at least 1 × 105 non-SP cells were needed to form a tumor (one of seven animals). Re-analysis of SPderived tumors by FACS showed that SP cells under in vivo conditions also have the capacity to regenerate the SP and non-SP fractions. Besides, analysis of Hoechst33342 revealed s small fraction of SP cells, ranging from 0. 27％ to 2.3％ in gallbladder carcinoma specimens. Conclusion SP cells from GBC-SD are highly tumorigenic similar as the cancer stem cells.