Abstract:

Objective To investigate the effect of protein kinase D inhibitor SD-208 on the proliferation， apoptosis and cell cycle of non-small cell lung cancer cells. Methods The A549 cells were treated with different concentrations of SD-208 （5， 10， 20， 30 μmol／L）， and the cells treated with only complete culture was used as the control group. MTT method was used to detect the absorbance of A549 cells at 24， 48， and 72 h after treatment and the proliferation inhibition rates were calculated accordingly. Staining with Annexin V-fluorescein isothiocyanate （Annexin V-FITC） and propidium iodide （PI） was employed to measure the apoptotic rates at 24 and 48 h via flow cytometry. The distribution of cell cycle phase was measured by PI staining after treatment with SD-208 for 48 h. Expression levels of Cyclin A， Cyclin D1, Cyclin E，cyclin dependent kinase 4 （CDK4） and p16 protein were detected by Western blotting. Results Compared with the control group， SD-208 could inhibit the proliferation of A549 cells （P＜0.05）， and the effect was exhibited in a dose- and time-dependent manner. As for SD-208 treated groups， apoptotic rates and percentages of G0／G1 phase cells were significantly higher than control group， and the proportion of S and G2／M cells were lower than those in control group （P＜0.05）. Compared with the control group， the levels of CDK4 and Cyclin D1 protein were decreased， and the level of p16 protein was increased after SD-208 treatment with statistical significance （P＜0.05）. SD-208 treatment had no effect on the level of Cyclin A and Cyclin E in A549 cells （P＞0.05）. Conclusion SD-208 could inhibit the proliferation of A549 cells and induce cell apoptosis and G0／G1 phase arrest， which may be related to its effect on cell cycle regulatory proteins.