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Resveratrol is a grape polyphenol with cancer preventative activities in tissue culture and animal model studies. Potential of resveratrol as a broad-based chemopreventive agent have been questioned by its limited bioavailability. The bioefficacy of resveratrol was compared with its derivatives, triacetyl-resveratrol (trans-3,5,4′-triacetylstilbene) and trimethoxy-resveratrol (trans-3,5,4′-trimethoxystilbene) in both estrogen receptor-α (ERα)-positive MCF-7 and ERα-negative MDA-MB-231 breast cancer cells. Binding to integrin αvβ3 and control of cell proliferation and p53 were chosen as targets for comparative analysis using anin silicoand biochemical approach. Resveratrol and triacetyl-resveratrol interacted avidly and specifically with integrin αvβ3 through binding at the site targeted by the high affinity cyclic Arg-Gly-Asp (RGD) peptide. In contrast, binding of trimethoxy-resveratrol to this site was substantially less robust. Moreover, the different stilbenes also elicited diverse cellular and signaling responses in MCF-7 and MDA-MB-231 cells, as evidenced by analysis of colony formation, cell proliferation, cell cycle phase transition, the extent of phosphorylation of p53 at Ser15 and p53-inducible proteins, p21 and p53R2, respectively. Further, stilbene-elicited signaling cascade leading to p53 activation was examined in MCF-7 cells and results showed that resveratrol and triacetyl-resveratrol induced both ERK and p38 phosphorylation, whereas only marginal changes in state of phosphorylation in these two kinases were observed in trimethoxy-resveratrol-treated cells. Taken together, these results support that resveratrol and triacetyl-resveratrol regulate proliferation and gene expression in breast cancer cells by utilizing largely similar signaling molecules and pathways and cellular events, which appear quite distinct from those targeted by trimethoxy-resveratrol.