Immunolocalization of liver receptor homologue-1 (LRH-1) in human breast carcinoma: possible regulator of insitu steroidogenesis.

Liver receptor homologue-1 (LRH-1) belongs to a class of nuclear orphan receptor. We examined immunolocalization of LRH-1 in 106 breast carcinomas. LRH-1 immunoreactivity was detected in 43% of the invasive ductal carcinoma. It was negatively correlated with clinical stage, histological grade and HER2 status, and positively associated with sex-steroid receptors, steroidogenic acute regulatory protein, P450 side-chain cleavage, and 3beta-hydroxysteroid dehydrogenase. LRH-1 immunoreactivity was also detected in 28% of the ductal carcinoma in situ. These results suggest that LRH-1 is frequently detected in breast carcinoma tissues, and plays important roles including the regulation of in situ steroidogenesis.