PACE4 regulates apoptosis in human pancreatic cancer Panc‑1 cells via the mitochondrial signaling pathway

Abstract Previous studies have demonstrated the overexpression of paired basic amino acid cleaving enzyme 4 (PACE4) mRNA in prostate cancer tissues. This overexpression is correlated with higher circulating protein levels in certain patients, however, the role of PACE4 in apoptosis and the potential molecular mechanisms of pancreatic cancer remain to be elucidated. The aim of the present study was to investigate the effect and potential molecular mechanisms of PACE4 on apoptosis in the Panc‑1 pancreatic cancer cell line. Cell proliferation was assessed using a Cell Counting Kit‑8 assay. Apoptotic nuclear shrinkage was monitored using Hoechst 33258 staining. Caspase‑3/7 activities were measured using a colorimetric caspase‑glo 3/7 assay. Alterations in protein expression were monitored using Western blot analysis. The results indicated that PACE4 small interfering (si)RNA inhibited cell proliferation and activated caspase‑3/7 activities. In addition, PACE4 siRNA significantly increased apoptosis via the activation of caspase‑3 and the downregulation of anti‑apoptotic proteins, X‑linked inhibitor of apoptosis protein and phosphorylated‑Akt. In addition, the results showed deregulation of the B cell lymphoma‑2 (Bcl‑2)-associated X protein/Bcl‑2 ratio which led to the release of cytochrome c following PACE4 siRNA transfection. In conclusion, PACE4 siRNA may exert antitumor activity through the mitochondrial pathway and is expected to be a promising therapeutic strategy for the treatment of pancreatic cancer.