Effect of short-term ethanol on the proliferative response of Swiss 3T3 cells to mitogenic growth factors

Both adaptive and deleterious responses of cells to ethanol are likely triggered by short-term interactions of the cells with ethanol. Many studies have demonstrated the direct effect of ethanol on growth factor-stimulated cell proliferation. Using Swiss 3T3 cells whose growth was inhibited by ethanol in a concentration-dependent manner, we further investigated the molecular mechanisms of acute ethanol treatment by examining its effect on EGF- and PDGF-mediated cellular signaling systems for the mitogenic function. Tyrosine autophosphorylation of the growth factor receptors was partially prevented by ethanol in intact cells. When ethanol was included before or after EGF stimulation, no effect on the receptor signaling was observed. Here we also report that ethanol inhibits activation of ERK induced by both EGF and PDGF. EGF-induced JNK activation was reduced but PDGF-induced rapid JNK activation was delayed by the addition of ethanol. The balance between its inhibitory and stimulatory effect on the signaling molecules might determine the rate of cell growth.