Oleuropein Promotes DNA Damage in Prostate Cancer Cells via HIF-1α Downregulation

This study aimed to investigate the effects of oleuropein (Ole) on prostate cancer (PCa) cells and its underlying mechanisms, particularly whether it mediates DNA damage through HIF-1α. PCa cells DU145 were treated with different concentrations of Ole (25, 50, 100, 250, and 500 μM) or transfected with HIF-1α overexpression plasmid. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect the cell viability; flow cytometry was used to detect apoptosis; quantitative reverse transcription polymerase chain reaction and western blot were employed to measure HIF-1α expression levels. Additionally, comet assay and western blot were employed to evaluate DNA damage and the expression of DNA damage-related proteins (γH2AX and p53). Ole significantly inhibited DU145 cell viability in a concentration-dependent manner (p < 0.01). Additionally, apoptosis rates increased significantly with increasing Ole concentrations (p < 0.01). Ole induced DNA damage in DU145 cells. Notably, overexpression of HIF-1α partially reversed the effects of Ole on PCa cells. Ole inhibits DU145 cell viability, promotes apoptosis, and induces DNA damage, possibly through the HIF-1α pathway. HIF-1α plays a potential role in the anticancer effects of Ole, providing new experimental evidence for its application in PCa research.