Dr. Weeks’ Comment: Again, diet trumps chemotherapy, radiation and surgery as a preventive measure for treating cancer. Simply stated, eat more fiber.
PROLONGED BUTYRATE TREATMENT INHIBITS THE MIGRATION AND INVASION OF POTENTIAL HT1080 TUMOR CELLS
Zeng, H., Briske Anderson, M.J. Journal of Nutrition. 135:291-295.
Technical Abstract: Butyrate, a normal constituent of the colonic luminal contents, is produced by the bacterial fermentation of dietary fibers and resistant starches. It has been hypothesized that butyrate may inhibit the invasion of tumor cells. The purpose of the present study was to investigate the effects of prolonged butyrate treatment on the growth, migration, and invasion characteristics of HT1080 cells, a well defined human invasive cancer cell line. HT1080 cells cultured in the presence of 0.5 and 1 mmol/L butyrate for 14 days exhibited an increase in the G1 and G2 fractions with a concomitant drop in the S-phase, thus showed slower cell growth. Interestingly, both 0.5 and 1 mmol/L butyrate inhibited the migration rate (53% and 67%, respectively), and invasion rate (74% and 79%, respectively) of the tumor cells when compared with the untreated (control) cells. The protein and mRNA level of the tissue inhibitors of metalloproteinase-1 (TIMP-1) and TIMP-2 were significantly increased in HT1080 cells cultured with 0.5 and 1 mmol/L butyrate. Enzymatic activities and the mRNA level of the latent forms of matrix metalloproteinase (MMP), pro-MMP-2 and pro-MMP-9, were also increased in HT1080 cells cultured with 0.5 and 1 mmol/L butyrate. In contrast, the active form of MMP-2 was detectable by zymographic analysis in control but not butyrate conditioned media. Collectively, these results demonstrate that prolonged and low-dose butyrate treatment enhances both pro-metastasis MMP-2, -9 and anti-metastasis TIMP-1, -2 expression. However, the net effect is the inhibition of the active form of MMP-2. More importantly, the inhibitory effect of prolonged 0.5 mmol/L butyrate treatment on cell migration and invasion potential was far greater than its effect on cell growth.
It has been reported that human populations and animal models consuming high levels of dietary fiber or resistant starches are associated with lower risk of colon cancer. This may be related to butyrate production in the colonic lumen by the bacterial fermentation of dietary fiber. Human fecal water containing butyrate has been shown to modulate cell differentiation, cell invasion, cell proliferation, cell cycle, and cell apoptosis in in vitro models, particularly in colon cancer cell lines, where butyrate may exert several anticancer effects. In the present study, the effects of prolonged butyrate treatment on the growth, migration, and invasion characteristics of HT1080 cells, a well defined human invasive cancer cell line, were examined. The data provide a mechanistic basis for considering specific relationship between butyrate and colon cancer risk. These findings will be useful information for scientists and health-care people who are working on nutrition and cancer prevention.