Neferine-induced apoptosis is dependent on the suppression of Bcl-2 expression via downregulation of p65 in renal cancer cells

摘要

Neferine is an alkaloid extracted from a seed embryo of Nelumbo nucifera and has recently been shown to have anticancer effects in various human cancer cell lines.However,the detailed molecular mechanism of neferine-induced apoptosis has not been elucidated in renal cancer cells.In the present study,we observed that neferine induced inhibition of cell proliferation and apoptosis in Caki-1 cells in a dose-dependent manner by using MTT assay and flow cytometry and that neferine-mediated apoptosis was attenuated by pretreatment with N-benzyloxycarbony-Val-Ala-Asp (O-methyl)-fluoromethyketone,a pan-caspase inhibitor.Treatments with neferine dosedependently downregulated B cell lymphoma-2 (Bcl-2) expression at the transcriptional level determined by reverse transcriptase-polymerase chain reaction.The forced expression of Bcl-2 and p65 attenuated the neferine-mediated apoptosis in Caki-1 cells.In addition,neferine induced apoptosis by downregulating Bcl-2 and p65 expression in the other two kidney cancer cell lines determined by flow cytometry and western blot analysis.Finally,we observed that treatment with neferine induced apoptosis by inhibiting the NF-κB pathway through caspase-mediated cleavage of the p65 protein by western blot analysis.Collectively,this study demonstrated that neferine-induced apoptosis is mediated by the downregulation of Bcl-2 expression via repression of the NF-κB pathway in renal cancer cells.