Effects of indole‐3‐carbinol on adipocyte‐induced invasion‐associated factors on breast cancer cells

Abstract

Indole‐3‐carbinol (I3C), one of the major indolic derivatives in cruciferous vegetable, has been reported to inhibit the invasion of the breast cancer cells and reduce body weight in high fat diet‐induced obesity mice. Because obesity is positively associated with breast cancers, and because the information on the relationship between adipocytes and breast cancer cells is limited, this study was aimed at investigating the cross‐talk among I3C, adipocytes as well as breast cancer cells on invasion‐association factors. After the breast cancer cells were cultivated with the condition medium (CM) from differentiated 3T3‐L1 adipocytes in the presence or absence of I3C for 24 h, the medium was then collected for analyses of cell proliferation, nitric oxide (NO), vascular endothelial growth factor (VEGF), and matrix metalloprotease (MMP). The results indicated that the CM from differentiated adipocytes significantly enhanced cell proliferation and increased VEGF production in breast cancer cells, whereas I3C inhibited such induction. On the other hand, high MMP activity observed in CM was also inhibited by I3C treatment, although no effects on NO production was noticed. In conclusion, mediators released from adipocytes had direct effects on the breast cancer invasion‐associated factors, and I3C showed inhibitory effects on these factors.