Cytotoxic effect of pyocyanin on human pancreatic cancer cell line (Panc-1)

OBJECTIVE(S): Pyocyanin, a blue-green pigment produced by Pseudomonas aeruginosa, interferes with host redox cycles, which can lead to generation of reactive oxygen species and progressive cellular oxidative damage. The aim of this study was to assess the influence of pyocyanin on human pancreatic cancer cell line. MATERIALS AND METHODS: Polymerase Chain Reaction (PCR) was applied to confirm the existence of a specific pyocyanin producing gene (phzM). The pigment was then characterized by UV-visible, FT-IR, and HPLC analysis. Panc-1 cells were treated by different concentrations of pyocyanin and their cytotoxic effect as well as the induction of apoptosis/necrosis were evaluated by XTT assay and flow cytometry. RESULTS: An overnight pyocyanin treatment resulted in significant cell reduction in a concentration-dependent manner. Inhibition rate of 6 mg.ml-1 pyocyanin (the highest concentration) extracted from clinical and soil isolates of P. aeruginosa were 98.69±0.23 and 89.88±1.86%, respectively, which decreased as the pyocyanin concentration lessened. Pyocyanin could also induce dose-dependent apoptosis/necrosis in Panc-1 cells after 24 hr. CONCLUSION: We reported, for the first time, cytotoxic effects of pyocyanin against human pancreatic cancer cell line. Considering this effect of the pigment, study on pyocyanin as a potential anti-tumor biodrug requires further studies.