Iso-but Not Anteiso-Branched Chain Fatty Acids Exert Growth-Inhibiting and Apoptosis-Inducing Effects in MCF-7 Cells
Citation
Vahmani, P., Salazar, V., Rolland, D.C., Gzyl, K.E., Dugan, M.E.R. (2019). Iso-but Not Anteiso-Branched Chain Fatty Acids Exert Growth-Inhibiting and Apoptosis-Inducing Effects in MCF-7 Cells. Journal of Agricultural and Food Chemistry, [online] 67(36), 10042-10047. http://dx.doi.org/10.1021/acs.jafc.9b03549
Plain language summary
The present study compared the growth-inhibitory effects of four common beef and dairy branched chain fatty acids (BCFAs) in human breast cancer cells. Culturing cells with iso- but not anteiso-BCFA reduced cell viability. The incorporation of iso- was also greater than anteiso-BCFA. Iso-BCFA also downregulated expression of a gene which inhibits cell death (Bcl-2) and upregulated a gene which promotes cell death (Bax). Our findings suggest that the branching structure influences the anti-cancer effects of BCFAs, with iso being more potent than anteiso. Data from this trial adds to a growing list of fatty acids unique to ruminant animals, which exhibit anti-cancer activity, and have important human health implications due to their potential utility for cancer prevention and treatment.
Abstract
The present study compared the growth-inhibitory effects of four common branched chain fatty acids (BCFAs) found in beef and dairy fats including iso 15:0, anteiso 15:0, iso 17:0, and anteiso 17:0. MCF-7 human breast cancer cells were exposed for 72 h to media containing increasing doses (50 to-400 μM) of the four BCFA. Cell viability was not affected by any of the BCFA treatments at doses less than 200 μM. Culturing cells with 200 μM of iso-15:0 or iso-17:0 reduced cell viability by 27 ± 2.8 and 43 ± 8.3% at 24 h, 35 ± 4.6 and 49 ± 9.1% at 48 h, and 44 ± 6.8 and 57 ± 8.8% at 72 h posttreatment. In contrast, culturing cells with 200 μM of anteiso-15:0 or anteiso-17:0 did not affect cell viability for any durations tested. The incorporation of iso 15:0 and iso 17:0 into cells (19.1 ± 1.3 and 21.2 ± 1.4 μmol/mg protein, respectively) was greater (P < 0.01) than that of anteiso 15:0 and anteiso 17:0 (11.8 ± 0.7 and 13.8 ± 0.8 μmol/mg protein, respectively). Iso-15:0 and iso-17:0 downregulated (P < 0.01) the expression of antiapoptotic Bcl-2 (0.71 ± 0.6-fold and 0.64 ± 0.09-fold, respectively) and upregulated (P < 0.01) the expression of proapoptotic Bax (1.72 ± 0.14-fold and 2.15 ± 0.24-fold, respectively) compared to the control, whereas their corresponding anteiso isomers did not affect the expression of any apoptosis-related genes. Our findings suggest that the branching structure influences anticarcinogenic effects of BCFAs, with iso being more potent than anteiso.