MUC1 upregulation by ethanol.

MUC1 is a glycoprotein and its expression is altered in breast cancer. Mucin protects epithelia from the external hostile environment. The expression of mucin changes when epithelia come in contact with toxic agents such as ethanol. Previously, we characterized the expression and regulation of tracheo-bronchial mucin (TBM) gene. In the present study, we studied the effect of ethanol on the gene encoding mammary gland mucin MUC1 and observed that ethanol regulates MUC1 expression at the transcription level. Ethanol enhanced the expression of MUC1 mRNA in a dose- and time-dependent manner in MCF-7 cells. At 100 mM concentration (a concentration reported to be present in alcoholics), ethanol induced a three to five-fold increase in mucin transcription as determined by nuclear run on analysis. This concentration of ethanol does not affect the half-life of MUC1 mRNA.