Gastrointestinal cancers, in particular colon and pancreatic cancer, account for almost 100,000 deaths each year in the United States, ranking third and fourth respectively, in the most common cause of cancer related deaths. Our lab has been focused on developing strategies for chemoprevention rather than treatment after diagnosis. For pancreatic cancer, the prognosis is usually poor with high mortality rates after diagnosis. Thus, the objective of this work was to study the effects of chemopreventive combination regimens of a non-steroidal anti-inflammatory drug (NSAID) naproxen (N), in combination with resveratrol (R, an antioxidant) and sulforaphane (S, a broccoli extract) on human colon (HT-29 and HCT-116) and pancreatic (MIA PaCa-2 and Panc-1) cancer cell lines. MTS cell proliferation assay was conducted on all cell lines. For the MTS assay, upon 75 % confluence, 100µL of 2.5X103 cells each of HT-29, HCT116 and MIA PaCa-2 and 4X10 3 cells Panc-1 cells were transferred into each well of 96-well plates. The NRS chemopreventive agents alone, or in combination, were added to the cells and incubated for 72 h. The plates were then incubated for 1-4 h at 37°C in a humidified, 5% CO2 atmosphere. Absorbance was recorded at 490 nm using an ELISA plate reader. For HT-29 and HCT 116 colon cancer cell lines, the combinations of naproxen (500µM/L) with resveratrol (50µM/L) and sulforaphane (5µM/L) showed reduction in cell viability of 56.74% and 52.9%, respectively. The IC50 values for NRS were 1.46 mM/L,104.54µM/L and 17.81µM/L respectively on HT-29 cell line. Similarly, for MIA PaCa-2 and Panc-1 pancreatic cancer cell lines, combinations of naproxen (500µM/L) with resveratrol (6µM/L) and sulforaphane (5µM/L) showed reduction in cell viability of 66.67% and 58.8% respectively. The IC50 values for NRS were 778µM/L, 74.8µM/L and 11.82µM/L respectively, on MIA Paca-2 cell line. When used individually, none of the chemopreventive agents at the above concentrations demonstrated any decrease in cell viability, however when combined together, a synergistic effect was observed. Our results demonstrate that NRS drug combinations at low concentrations exhibit significant decrease in cell proliferation in both human colon and pancreatic cancer cell lines. This data provides compelling evidence of the potential of these combination regimens for the chemoprevention of colon and pancreatic cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1632. doi:1538-7445.AM2012-1632