Sirtuin 4 Inhibits Prostate Cancer Progression and Metastasis by Modulating p21 Nuclear Translocation and Glutamate Dehydrogenase 1 ADP-Ribosylation

Figure 4

SIRT4 restrains AKT phosphorylation and promotes p21 nuclear localization. (a) The cell cycle of SIRT4-overexpressing and SIRT4-knockdown cells were detected by flow cytometry. (b) The mRNA expression of p21 in SIRT4-overexpressing and SIRT4-knockdown cells were contrasted by qRT-PCR. (c) The pivotal members (AKT, p-AKT, p21, p-P21, cyclin D1, and CDK4) protein levels were determined by western blotting in SIRT4-knockdown 22rv1 and SIRT4-overexpressing PC-3 cells. (d) Nuclear and cytoplasm extraction assay. The p21 protein expression of SIRT4-overexpressed PC-3 and 22rv1 cells in nuclear and cytoplasm was analyzed by western blotting, respectively. (e) Immunofluorescence was used to ensure the location of p21 more directly in SIRT4-overexpressing PC-3 and 22rv1 cells. Red fluorescence represents p21, and nuclear was stained by DAPI (blue).

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