Interaction of o,p'-DDT with the estrogen-binding protein (EBP) of DMBA-induced rat mammary tumors.

The effect of o,p'-DDT on the binding of 3H-estradiol to DMBA-induced rat mammary tumor cytosolic estrogen-binding protein (EBP) was examined in vitro. Scatchard plot analysis indicated that o,p'-DDT competitively inhibited 3H-estradiol binding and sucrose density gradient analysis demonstrated that o,p'-DDT displaced estradiol from specific 4S and 8S proteins. As estrogens have been shown to affect the development and growth of these tumors, our experimental findings suggest that o,p'-DDT may possibly influence DMBA-induced tumors in an estrogenic manner.