The effect of exogenous superoxide dismutase (SOD) on caspase-3 activation and apoptosis induction in PC-3 prostate cancer cells

Background: This study aimed to assess the effects of exogenous SOD administration on prostate cancer cell line (PC-3) apoptosis via the intrinsic pathway by examining the expression of manganese superoxide dismutase (MnSOD), caspase-3, and apoptosis index of the PC-3 cell line. Methods: We used the prostate cancer cells from secondary prostate cancer cell lines (PC-3) derived from castration refractory prostate cancer (CRPC), cell differentiation grade IV, and had metastasized to the bone from the American Type Culture Collection (ATCC, Rockville, MD, USA). Superoxide dismutase (SOD) is derived from extracts of melon seeds and wheat gliadin biopolymer, and divided into 62.5 mg/mL, 83 mg/mL, 125 mg/mL, and 250 mg/mL doses. Expression of MnSOD was measured by immunohistochemistry (IHC). Expression of caspase-3 was measured using Western Blot method. Apoptotic index is calculated based on the reaction introduction 3OH end of fragmentation of DNA by the enzyme terminal transferase in preparations with TUNEL staining reagents. A one-way ANOVA test and Pearson correlation test were used to determine the relationship between SOD with expression of caspase-3 and apoptotic index. Results: SOD extract significantly increased the expression of caspase-3 (P=0.016) and the apoptotic index (P=0.000) (P<0.05). There was a correlation between the increased doses of SOD extract and the apoptosis index (P=0.015; r=0.679) and between the increased caspase-3 expression and the apoptosis index (P=0.015; r=0.682). Conclusion: Administration of superoxide dismutase (SOD) increased apoptosis in a prostate cancer cell line (PC-3) through the increased expression of caspase-3. Superoxide dismutase (SOD) can be considered as a therapy for late-stage prostate cancer that had been progressed to hormone resistant and metastasized and promote apoptosis in those prostate cancer cells.