Arsenic trioxide inhibits proliferation and induces apoptosis in pancreatic cancer cells

Because of the poor therapeutic responsiveness of pancreatic cancer patients, new chemotherapeutic agents for pancreatic cancer would be extremely beneficial. The effects of arsenic trioxide in pancreatic cancer have not been explored. To evaluate the anti-pancreatic cancer effects of arsenic trioxide, three human pancreatic cell lines, HPAF, MiaPaCa-2 and PANC-1, were tested. Arsenic trioxide caused dose- and time dependent inhibition of pancreatic cancer cell proliferation. In parallel with inhibition of cell proliferation, arsenic trioxide induced significant morphological changes, including shrunken cytoplasm, membrane blebbing, and nuclear condensation consistent with apoptosis. Propidium iodide DNA staining showed an increase of the sub-G0/G1 cell population. The DNA fragmentation induced by arsenic trioxide in these three cell lines was confirmed by the TUNEL assay. Furthermore, Western blotting analysis indicated that caspase-3 was activated following arsenic trioxide as measured by procaspase-3 cleavage and PARP cleavage. These findings show that arsenic trioxide has potent anti-proliferative effects on human pancreatic cancer cells with induction of apoptosis in vitro.