Involvement of promyelocytic leukemia protein in the ethanol-induced apoptosis in mouse embryo fibroblasts.

The promyelocytic leukemia (PML) gene is a tumor suppressor gene associated with cell apoptosis, cell proliferation, and senescence. However, the role of PML in the ethanol-induced apoptosis is not fully-known. In this study, using wild-type mouse embryo fibroblasts (MEF) and PML null MEF cells, we found that (1) ethanol (100 mM and 200 mM) could obviously induce apoptosis of wild-type MEF cells, whereas, in PML null MEF cells, the pro-apoptotic function of ethanol was partially blocked; (2) the expression levels of phosphorylated p53 and two of its target genes, p21 and Bax, could be significantly up-regulated by ethanol (200 mM) in wild-type MEF cells in a time-dependent manner, but not in PML null MEF cells. These results indicate that PML plays an important role in ethanol-induced apoptosis, and p53-dependent apoptotic pathway may be involved in this process.