In the practice of developing efficacious anti‐cancer drugs, repositioning of current clinical drugs may serve as an attractive approach owing to their favourable in vivo safety and relatively clear pharmacokinetics and pharmacodynamics.41, 42 Dr Jung and colleagues found that pentamidine reduced expression of hypoxia‐inducible factor‐1α (HIF‐1α) in DU145 cells.34 In the present study, we examined the activity of pentamidine in several prostate cancer cells, including PC3, DU145, LAPC4 and LNCap, as well as normal prostate epithelial cells, RWPE‐1. The gene discussed is HIF1A; the disease is prostate cancer.