In vitro study on the anticancer effects of oxalipalladium against PC3 human prostate carcinoma cells

Prostate cancer is a common type of cancer in men with high incidence and mortality. Our aim was to investigate the effects of oxalipalladium (ox-Pd) on metastatic human prostate cancer PC3 cells and compare them with the effects of oxaliplatin (ox-Pt) (as an approved cancer drug). We synthesized ox-Pd through a new chemical method and used FT-IR, ¹H NMR, ¹³C NMR, and MS analyzes to characterize it. The effects of ox-Pd on PC3 cells viability, apoptosis, cell cycle, migration, and gene expression were examined. Inhibition of topoisomerase IIα activity was investigated by pHOT1 plasmid relaxation and kDNA decatenation assays. Chemical tests showed ox-Pd with the correct composition and structure. For the first time, the exact fragmentation pathway of ox-Pd and its difference with ox-Pt was obtained by MS analysis. Ox-Pd significantly decreased PC3 cell viability with less/no toxicity effect on MHFB-1 normal skin fibroblasts. Wound scratch assay confirmed the strong anti-migratory activity of ox-Pd. According to flow cytometry analysis, this drug increased the number of PC3 cells in late apoptosis and decreased DNA replication and mitosis. Furthermore, pHOT1 plasmid relaxation and kDNA decatenation assays showed that ox-Pd strongly inhibited the catalytic activity of topoisomerase IIα. The expression of topoisomerase IIα, Bcl-2, P21, and survivin was decreased while the expression of Bax and p53 was increased under ox-Pd treatment. We provide the first evidence that ox-Pd exhibits more selective anticancer effects on PC3 cells compared to ox-Pt. Taken together, these data strongly suggest a therapeutic window for ox-Pd in cancer.