RESUMEN
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.