Synergistic effect of siRNA-mediated silencing of TGF-β R1 and TGF-β R2 genes on the proliferation and apoptosis of penile urethral epithelial cells in hypospadiac male rats.

The study elucidated the effects associated with silencing growth factor-β R1 (TGF-β R1) and TGF-β R2 genes on the proliferation and apoptosis of penile urethral epithelial cells (UECs) in hypospadiac male rats. Seventy-five male rats were distributed into the normal, model, TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups. The UECs of the rats included in the study were cultured in vitro and subsequently divided into the control, blank, TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups. The mRNA and protein expressions of TGF-β R1/R2 were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Cell proliferation and apoptosis were evaluated by cell counting kit-8 (CCK-8) assay as well as by flow cytometry. Compared with the normal group, the apoptotic rate of the UECs in the model, TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups displayed remarkable increases; compared with the model group, the apoptotic rate of the UECs in the TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups displayed significant decreases, similar observations were made regarding mRNA and protein expressions of TGF-β R1 and TGF-β R2. Compared with the TGF-β R1/2-siRNA group, the apoptotic rates of the UECs in the TGF-β R1-siRNA and TGF-β R2-siRNA groups were up regulated, while cell proliferation in the TGF-β R1-siRNA and TGF-β R2-siRNA groups decreased accompanied by an increased rate of apoptosis. This study ultimately demonstrated that the silencing of TGF-β R1 and TGF-β R2 genes could promote cell proliferation and inhibit apoptosis of penile UECs in hypospadiac male rats.