化疗后残余胃癌细胞发生上皮间质转化的体外研究

Epithelial-mesenchymal transition in residual gastric cells after chemotherapy: An in vitro study

目的:观察体外化疗能否诱导胃癌细胞发生上皮间质转化(epithelial mesenchymal transition,EMT)。方法:使用5-Fu(30μg/mL)对胃癌细胞株SGC7901进行4个疗程的体外化疗,残余细胞继续培养,得到能稳定传代的细胞SGC7901/Fu。比较SGC7901及SGC7901/Fu在细胞形态、EMT标记物、化疗耐药性、侵袭能力、肿瘤干细胞特性等方面的差异。结果:与SGC7901比较,SGC7901/Fu呈间质细胞形态、上皮表型标记物表达下调、间质表型标记物表达上调。在SGC7901细胞及SGC7901/Fu细胞中,5-Fu的中效浓度(IC50)分别为(43.8±7.2)μg/mL及(64.6±5.5)μg/mL,穿过Transwell小室基底膜的细胞数分别为(51.4±8.7)个及(93.2±9.5)个,克隆形成率分别为5.2%±1.0%及13.2%±2.2%,CD44+/CD24-细胞亚群所占比例分别为4.13%±0.81%及7.97%±0.50%,两者间的差异均具有统计学意义(P<0.05)。结论:体外化疗后残余的胃癌细胞发生EMT,同时细胞侵袭能力增强、化疗耐药性升高,并获得了肿瘤干细胞特性。

Objective： To investigate if in vitro chemotherapy can induce the EMT progress in gastric cancer （GC） cells. Method： The GC cell line, SGC7901, was treated using 5-Fu at a concentration of 30 μg/mL. The residual cells after four cycles of 5-Fu therapy were named as SGC7901/Fu. The morphological changes and malignant biological features, including the invasiveness and clone formation ability and the characteristics of cancer stem cell and biomarkers of EMT between SGC7901 and SGC7901/Fu, were compared. Results： The SGC7901/Fu cells displayed a mesenchymal appearance, decreased the expression of epithelial markers, and increased the expression of mesenchymal markers. The 50% inhibitory concentrations in the SGC7901/Fu and SGC7901 cells were （43.8±7.2） and （64.6±5.5） μg/mL, respectively. The number of cells that migrated through the basement-membrane of the Transwell chamber was 51.4±8.7 and 93.2±9.5, respectively. The rate of clone formation was 5.2%±1.0% and 13.2%±2.2%, respectively. The portions of the CD44/CD24 cells were 4.13%±0.81% and 7.97%±0.50%, respectively. All differences were statistically significant （P〈 0.05）. Conclusion： The residual GC cells underwent EMT progress after 5-Fu treatment, with increased chemoresistance and ability of invasiveness and acquired the property of cancer stem cells.