Pterostilbene Inhibits Pancreatic Cancer In Vitro

Stilbenes are phenolic compounds present in grapes and blueberries. Resveratrol, a naturally occurring compound present in grapes, has been shown to have potent antioxidant properties as well as an ability to induce apoptosis. Resveratrol has also been reported to have significant inhibitory effects against a variety of primary tumors including breast, colon, and prostate. Pterostilbene, a naturally occurring analogue of resveratrol found in blueberries, also has antioxidant and antiproliferative properties. It is also substantially more bioavailable orally than resveratrol. These effects have not been studied in pancreatic cancer. We hypothesized that pterostilbene would inhibit pancreatic cancer cell growth in vitro. Two pancreatic cancer cell lines (MIA PaCa and PANC-1) were cultured using standard techniques. Cells were treated with graduated doses of pterostilbene ranging from 10 to 100 mu M. Cell viability was measured by MTT at 24, 48, and 72 h. Pterostilbene decreases cell viability in both cancer cell lines in a concentration- and time-dependent manner. Higher doses (75-100 mu M) caused a significant reduction in cell viability at 24 and 48 h. However, by 72 h, all tested concentrations of pterostilbene (10 to 100 mu M) resulted in significantly reduced cell viability in both pancreatic cancer cell lines in a dose-dependent fashion. Pterostilbene caused a dose-dependent 10-63% inhibition in MIA PaCa-2 cells and 10-75% inhibition in PANC-1 cells. Treatment of pancreatic cancer cells in vitro with Pterostilbene leads to inhibition of cell proliferation and/or cell death, cell cycle arrrest, mitochondrial membrane depolarization, and activation of effector caspases. This naturally occurring agent may have a role in treating pancreatic cancer. Pterostilbene inhibits the growth of pancreatic cancer in vitro. Further, in vitro mechanistic studies and in vivo experiments are warranted to determine its potential for the treatment of pancreatic cancer.