In Vitro Study Of The Effect Of MiR-34a On Chemosensitivity Of Prostate Cancer Cells

Objectives:To investigate the effect of miR-34 a on chemosensitivity of prostate cancer cell lines.Methods:In the first part,MTT assays the effects of miR-34 a and 5-Aza on the proliferation of two PCa cells: 1.mimic NC,miR-34 a mimic transfection and 5-Aza demethylation respectively treated two PCa cells PC-3,DU145 48h;2.MTT detection of each group of PCa cells at a wavelength of 570 nm absorbance(time 0/24/48/72h)grouping:PC-3: Con group,pre-Con group,pre-miR-34 a group,5-Aza group;DU145: Con group,pre-Con group,pre-miR-34 a group,5-Aza group.In the second part,MTT assays the effects of miR-34 a and 5-Aza on the drug resistance of two PCa cells: 1.mimicNC,miR-34 a mimic transfection and 5-Aza demethylation respectively treated two PCa cells PC-3,DU145 48h;2.Simultaneously select different concentrations of Dox and Topo to act on each group of PCa cells for 48h(Dox concentration:0,0.0625,0.125,0.25,0.5,1.0,2.0umol / L;Topo concentration: 0,0.0195,3.78,0.3125,1.25,5.0 mg/L);3.MTT detected the absorbance of PCa cells at a wavelength of 570 nm,and calculated the IC50 values of Dox and Topo in each group of PCa cells.Grouped(two chemotherapy drugs): Con group,pre-con group,pre-miR-34 a group,5-Aza group.In the third part,the effects of Dox,Topo,5-Aza and miR-34 a on apoptosis of two PCa cells were detected by flow cytometry: 1.miR-34 a mimic transfection and 5-Aza demethylation were treated separately.PCa cells,PC-3,DU145 cells for 48h;2.Flow cytometry to detect the apoptosis rate of PCa cells in each group;group(two PCa cells): Con group,Dox group,Topogroup,pre-miR-34 a group,pre-miR-34a+Dox group,pre-miR-34a+Topo group,5-Aza group,5-Aza+Dox group,5-Aza+Topo group.Results:After mimic NC,miR-34 a mimic transfection and 5-Aza demethylation were used to treat PCa cells PC-3 and DU145 respectively,the results of MTT assay showed that the absorbance of the two PCa cells in the miR-34 a mimic transfection or 5-Aza demethylation group at 570 nm was lower than that of the mimicNC treatment group and the blank treatment group;indicating that miR-34 a mimics transfection or 5-Aza demethylation induced up-regulation of miR-34 a could inhibit PCa cells PC3,DU145 Proliferation.After adding different concentrations of Dox and Topo drugs,the IC50 values of Dox and Topo in each group of PCa cells were determined by MTT: miR-34 a mimic transfection group or two PCa cells treated by 5-Aza demethylation group The IC50 values of Dox and Topo were lower than those of mimicNC treatment group and blank treatment group;indicating that miR-34 a mimics transfection or 5-Aza demethylation induced up-regulation of miR-34 a expression could reduce the IC50 of Dox and Topo on two PCa cells.The value suggests that miR-34 a mimics transfection or 5-Aza demethylation induces up-regulation of miR-34 a to increase the chemosensitivity of Dox and Topo to PC3 cells and DU145.Further,the results of flow cytometry showed that the apoptosis rate of the two PCa cells was significantly increased in the Dox group,the Topo group,the pre-miR-34 a group,and the 5-Aza group compared with the Con group;The apoptosis rate of the two PCa cells was increased in the pre-miR-34a+Dox(Topo)group compared with the Dox group,the Topo group,and the pre-miR-34 a group.Similarly,the apoptotic rate of the two PCa cells was increased in the 5-Aza+Dox(Topo)group compared with the single Dox group,the Topo group,and the 5-Aza group.This indicates that up-regulation of miR-34 a expression by miR-34 a mimics transfection or 5-Aza demethylation can promote apoptosis of PC-3 cells and DU145 cells,and enhanced the chemosensitivity of Dox and Topo to PCa cells PC-3 and DU145.Conclusions:1.miR-34 a may inhibit the proliferation of PCa cells.2.miR-34 a may promote apoptosis of PCa cells.3.miR-34 a may increase the chemosensitivity of PCa cells.