饱和脂肪酸和不饱和脂肪酸对肺癌细胞增殖与自噬的影响

目的 研究饱和脂肪酸和不饱和脂肪酸对肺癌细胞增殖与自噬的影响.方法 用0、30、60、120、240μmol/L硬脂酸(饱和脂肪酸)和DHA(不饱和脂肪酸)分别处理肺癌细胞A549,绘制细胞生长曲线并计算克隆形成率以检测细胞增殖.采用硬脂酸和DHA分别处理A549细胞24h后,采用激光共聚焦显微镜从形态学方面观察细胞自噬情况.采用硬脂酸和DHA分别处理A549细胞12、24、36h后,用Western blotting检测细胞自噬相关蛋白的表达.结果 30~240μmol/L硬脂酸和DHA均有抑制A549细胞增殖的作用(P<0.05),硬脂酸、DHA处理A549细胞24h后均检测到细胞出现明显的自噬;Western blotting结果 显示,硬脂酸、DHA分别处理A549细胞12、24、36h后,LC3Ⅱ/LC3Ⅰ比值升高(P<0.05),哺乳动物雷帕霉素靶蛋白(ser2481)磷酸化水平降低(P<0.05).结论 饱和脂肪酸和不饱和脂肪酸均有抑制肺癌细胞增殖、诱导肺癌细胞自噬的作用,其机制可能与p-mTOR(ser2481)信号通路有关.

Effects of saturated and unsaturated fatty acids on proliferation and autophagy of lung cancer cells

Objective To investigate the effects of saturated fatty acids and unsaturated fatty acids on proliferation and autophagy of human lung cancer cells. Methods The lung cancer cells A549 were treated with stearic acid (saturated fatty acid) and doconexent (DHA, unsaturated fatty acid), respectively, in concentrations of 0, 30, 60, 120 and 240μmol/L. MTT test and cell clone formation assay were performed to detect the proliferation of A549 cells. The morphology of A549 autophagy was observed by confocal laser scanning microscopy after A549 cells were treated with stearic acid or DHA for 24 hours. Western blotting assay was used to detect the expression of autophagy-related protein after A549 cells were treated with stearic acid or DHA for 12, 24 and 36 hours, respectively. Results 30-240μmol/L stearic acid or DHA both inhibited the proliferation of A549 cells (P<0.05). Both stearic acid and DHA induced autophagy of A549 cells, meanwhile, down-regulated Phospho-mTOR (ser2481) and up-regulated LC3Ⅱ/LC3Ⅰ of A549 cells (P<0.05). Conclusions Both saturated fatty acid and unsaturated fatty acid can inhibit the proliferation and induce autophagy of lung cancer cells. The mechanisms of autophagy may be related to Phospho-mTOR (ser2481) signaling pathway.