Topical Area: Dietary Bioactive Components
Objectives : The isothiocyanate sulforaphane and the polyphenols chrysin, epigallocatechin-3-gallate, and resveratrol are dietary micronutrients that are thought to exhibit potential in cancer prevention. These compounds are commonly found in the human diet, and previous research suggests that they may play a role in cellular processes that are often labeled as the ‘hallmarks of cancer’. Our goal is to investigate the impact of these dietary nutrients on the expression of genes associated with apoptosis, metastasis, and invasion, and thus their potential role in regulating the expression of genes involved in colon cancer.
Methods : Colorectal cancer cells were incubated for up to 48 h. RNA was extracted with Trizol/Chloroform, and reverse-transcribed to cDNA. mRNA expression was quantitated using qPCR, normalized to Gapdh, and analyzed using GraphPad Prism. Total protein was extracted using lysis buffer for subsequent Western blotting and catalytic activity assays.
Results : Our preliminary results suggest that especially the isothiocyanate sulforaphane increases mRNA expression of apoptosis-regulatory genes, such as Cyclooxygenase 2 (p< 0.05) and Bcl-2-associated X protein (p< 0.05), whereas cell proliferation genes, such as cyclin B1 and KRAS remained largely unaffected. Furthermore, matrix metalloprotease 9 expression was significantly inhibited by sulforaphane, but not by the polyphenols investigated.
Conclusions : Among the dietary micronutrients investigated thus far, sulforaphane significantly altered mRNA expression of genes associated with the hallmarks on cancer. Further investigations involving both shorter and longer-term incubation times, as well as effects on protein expression and activity will help elucidate the effects of sulforaphane and other micronutrients potentially important in colon cancer. Our results may help to understand how commonly eaten dietary compounds may contribute to cancer prevention strategies.
Funding Sources :
Financial support was provided by Towson University’s Fisher College of Science and Mathematics (P. Tsuji) and an FCSM undergraduate research grant to M. Darkwa.