Resveratrol suppresses migration, invasion and sternness of human breast cancer cells by interfering with tumor-stromal cross-talk

Cancer-associated fibroblasts (CAFs) constitute a major compartment of the tumor microenvironment. CAFs produce a variety of cytokines, growth factors and extracellular matrix proteins, thereby stimulating tumor progression. CAFs are distinct from normal fibroblasts for their overexpression of a-smooth muscle actin. Recent studies suggest that CAFs play an important role in proliferation and migration of cancer cells through cross-talk with them. Resveratrol (trans-3,4'5,-trihydroxystilbene), a phytoalexin present in grapes, has been reported to possess chemopreventive and chemotherapeutic activities. In the present study, we examined the effects of resveratrol on CAF-induced migration, invasion and self-renewal activity of breast cancer cells. Resveratrol inhibited proliferation, migration and invasion of human breast cancer cells treated with CAF-conditioned media (CAF-CM). Resveratrol treatment suppressed the CAF-CM-induced expression of Cyclin D1, c-Myc, MMP-2 and MMP-9. In addition, resveratrol inhibited Sox2 expression as well as activation of Akt and STAT3 induced by CAF-CM in breast cancer cells. Further, resveratrol abrogated stemness properties and reduced the expression of self-renewal signaling molecules in stem-like breast cancer cells. Taken together, the present study provides insights into the role of resveratrol in tumor microenvironment with focus on interaction between cancer cells and the hosting niche.