Inhibition of gap-junctional intercellular communication between Chinese hamster lung fibroblasts by di(2-ethylhexyl) phthalate (DEHP) and trisodium nitrilotriacetate monohydrate (NTA).

Di(2-ethylhexyl)phthalate and trisodium nitrilotriacetate monohydrate, two apparently nongenotoxic carcinogens, were tested for effects on gap-junctional communication between Chinese hamster V79 lung fibroblasts. Both compounds inhibited gap-junctional communication in a concentration-dependent manner. The inhibiting effects of these chemicals on gap-junctional communication in vitro correlate with their tumor-promoting activity. Such results further support the hypothesis that inhibition of gap-junctional communication is an in vitro biomarker for some tumor-promoting chemicals.