p73 is highly expressed in myoepithelial cells and in carcinomas with metaplasia

p73, a homologue of p53 gene, is expressed in several normal tissues including central nervous system, but data regarding tumors are scant. In this study, we have analyzed the status and expression of the p73 gene in primary breast tumors, as well as 4 normal salivary glands, 2 carcinomas with metaplasia and mixed tumors. We found that periductal myoepithelial cells of all of the mammary gland examined were clearly stained with the specific anti-p73 antibody. Furthermore, we found the expression of p73 in the neoplastic myoepithelial cells in carcinomas with metaplasia and in mixed tumors. The findings in the present study provide valuable information on the characteristics of myoepithelial cells.