c-Jun Transcriptional Regulates NPRL2 to Promote the Proliferation Activity of Prostate Cancer Cells via AKT/MDM2/p53 Signaling Pathway

Abstract BackgroundHigh NPRL2 (Nitrogen permease regulator-like 2) expression is a prognostic marker for poor clinical outcomes in prostate cancer (PCa). However, the regulatory mechanisms of NPRL2 in PCa remain unknown.MethodsThe expression level of NPRL2 in prostate cancer tissues were verified through The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The effect of NPRL2 gene in promoting the proliferation of prostate cancer was determined by CCK8 and clone formation assays. The apoptosis rate and cell cycle analysis were tested by flow cytometry. Luciferase reporter gene and ChIP were used to verify the binding relationship between transcription factor c-Jun and the NPRL2 5’ region. The effect of NPRL2 and the MK2206 on the AKT/MDM2/p53 signaling pathway was verified by western blotting.ResultsNPRL2 expression level was significantly increased in prostate cancer tissues than normal tissues base on TCGA and GEO database. We investigated that transcription factor c-Jun can bind to the NPRL2 promoter and regulated NPRL2 transcription directly. Then, we revealed that NPRL2 significantly promotes proliferation and reduces apoptosis in PCa cells. Further mechanistic investigations revealed that NPRL2 mediated proliferation promotion effect is associated with the AKT/MDM2/p53 pathway's participation. Besides, CDK2 might serve as an intermediate effector for NPRL2 to regulate the AKT pathway. ConclusionTaken together, our study identified that c-Jun contributes to transcriptional control of NPRL2 and NPRL2 can promote prostate cancer proliferation by activating AKT/MDM2/p53 signaling.