Inhibition of apoptosis by pentachlorophenol in v-myc-transfected rat liver epithelial cells: relation to down-regulation of gap junctional intercellular communication

Pentachlorophenol (PCP), a promoter of murine hepatocarcinogenesis, inhibit s gap junctional intercellular communication (GJIC) in rat liver epithelial cells in vitro. To test the hypothesis that both inhibition of GJIC and ap optosis contribute to tumor promotion, we investigated the effect of PCP on both GJIC and serum deprivation-induced apoptosis in v-myc-transfected rat liver epithelial cells. The results showed that PCP inhibited apoptosis, a s measured by the TUNEL assay and DNA ladder formation. Inhibition of apopt osis was associated with a decrease in GJIC. The study demonstrated that PC P has a potential for inhibiting apoptosis and GJIC, supporting the hypothe sis. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.