1.Study on Reversal Effects of Levoshikonin on Cisplatin Resistance of Human Cervical Carcinoma HeLa Cells
Chunshuang DU ; Yani MA ; Shuai WANG ; Fei ZHANG ; Jie ZHANG ; Guangjian SANG
China Pharmacy 2020;31(15):1867-1873
OBJECTIVE:To investigate the reversal effects and potential mechanism of levoshikonin (L-SHK)on cisplatin (DDP)resistance of human cervical carcinoma HeLa cells. METHODS :Human cervical carcinoma HeLa cells were used as research objects ,and drug-resistant HeLa/DDP cells were induced by DDP. CCK- 8 assay was used to determine drug resistance index of HeLa/DDP cells ,the inhibition rate of different doses of L-SHK (0.125,0.25,0.5,1,2,4,8,16 μmol/L)on cell proliferation,IC50 and the reversion index of L-SHK on HeLa/DDP cells. Effects of low ,medium and high doses of L-SHK (0.3, 0.6,1.2 μmol/L)combined with DDP on cell cycle and apoptosis rate were determined by flow cytometry. Western blotting assay was used to detect the effects of low ,medium and high doses of L-SHK (0.3,0.6,1.2 μmol/L)combined with DDP on the expression of apoptosis-related protein (Cleaved caspase- 3,Bcl-2 and Bax ). RESULTS :The drug resistance index of HeLa/DDP cells was 11.8. The inhibition rate of L-SHK on HeLa/DDP cells increased with the increase of dose. Compared with DDP alone , IC50 of DDP+low-dose ,medium-dose and high-dose L-SHK groups were decreased significantly ,with a dose-dependent manner (P<0.05). The reversion indexes were 1.38,2.80,6.71 in DDP+low-dose ,medium-dose and high-dose L-SHK groups. Compared with blank control group ,the proportion of cells at phase G 0/G1 and phase S in administration groups ,as well as early and late apoptosis rate and total apoptosis rate of cells ,the protein expression of Bax and Cleaved caspase- 3 in L-SHK combination groups were increased significantly ;the proportion of cells at phase G 2/M in administration group as well as the protein expression of Bcl-2 in L-SHK combination groups were decreased significantly (P<0.05). Compared with DDP group ,the proportion of cells at phase S and G 2/M and the protein expression of Bcl- 2 in L-SHK combination groups were significantly decreased ;the proportion of cells at phase G 0/G1,early and late apoptosis rate and total apoptosis rate ,the protein expression of Bax and Cleaved caspase- 3 in L-SHK combination groups were significantly increased (P<0.05). CONCLUSIONS :HeLa/DDP cells are resistant to DDP ,and L-SHK can reverse the drug resistance. L-SHK combined with DDP can promote the apoptosis of HeLa/DDP cells ,which is better than DDP alone. Its mechanism may be related to the influence of cell cycle and the regulation of apoptosis-related protein expression.