Mechanism of regulating the resistance of prostate cancer PC-3 cells to cisplatin through enhancing cell gap junctions by evodiamine

Abstract

Objective To evaluate the effect of the combination of cisplatin and evodiamine on the growth of PC-3 cells and gap junction intercellular communication(GJIC). Methods Human prostate cancer PC-3 cells in logarithmic growth phase were cultured in vitro and then treated with various concentrations of cisplatin(5,10,15,20μmol/L)or evodiamine(0. 4μmol/L)combined with various concentrations of cisplatin(5, 10, 15, 20μmol/L).The effects of the proliferation was investigated by cell counting kit-8(CCK-8)assay.Apoptosis rate, and cell cycle distribution were examined by Annexin V-fluoresceine isothiocyanate(FITC)/propidium iodide(PI) double staining flow cytometry.The expression of connexin43(Cx43) protein was detected by Western blotting.The changes in the GJIC function were observed by FRAP. Results Fluorescence recovery rate was(41. 93± 1. 30)%,(36. 32±2. 33)%,(30. 81±1. 43)%, and(22. 54±1. 70)% in cisplatin groups, and (69. 86±2. 16)%,(50. 03±5. 00)%,(45. 38±2. 59)%, and(34. 01±4. 01)% in cisplatin+ evodiamine groups with statistically significant differences within groups respectively(P< 0. 05 for all). Fluorescence recovery rate, apoptosis rate, and the expression of Cx43 protein in cisplatin+ evodiamine groups were significantly increased as compared with cisplatin groups(P< 0. 05 for all). Conclusion Evodiamine could recover the gap junction intercellular communication through increasing the expression of Cx43 protein and enhancing the cytotoxicity of cisplatin to prostate cancer PC-3 cells. Key words: Evodiamine; Cisplatin; Prostate cancer; Gap junctioninter cellular communication