Effects of Methotrexate Enantiomers on Human Lung Cancer A549 Cells Inhibition and Its Apoptosis

OBJECTIVE To investigate the effect of methotrexate enantiomers included (+)MTX, (-)MTX on the proliferation and apoptosis of A549 cells. METHODS A549 cells were cultured. The cell proliferation was determined by MTT. The morphological changes were inspected by inverted microscope and fluorescence microscope. Cell cycle phases were assayed by propidium iodide staining flow cytometry. DNA ladder were used to detect the apoptosis. RESULTS A549 cells were treated with (+)MTX and (-)MTX at 1-150 μmol·L^-1 for 24, 48, 72 h. The results showed that the proliferations of A549 cells were significantly inhibited under the different conditions. The order of the inhibited efficacy was (+)MTX>(-)MTX. The morphological of A549 cells were found changes by (+)MTX and (-)MTX treatment. After administration of 10 μmol·L^-1 of (+)MTX and (-)MTX for 48 h, respectively, the cell cycle phases were assayed by propidium iodide staining flow cytometry. DNA ladder was the most recognized marker of apoptosis, and there was obvious DNA ladder in (+)MTX treated group. The result showed DNA replication was interfered by (+)MTX and (-)MTX treatment. CONCLUSION The proliferation of A549 cells have the chiral selective effects by (+)MTX and (-)MTX treatment, and the inhibition on A549 cells proliferation of (+)MTX was significantly stronger than (-)MTX.