Beta-hCG/LH receptor (b-HCG/LH-R) expression is increased in invasive versus preinvasive breast cancer: implications for breast carcinogenesis?

The role of the b-HCG/LH/LH-R system in breast cancer is conflicting. Whereas some reports suggest a protective effect of b-HCG on breast epithelium, vitro studies implicate a role of b-HCG/LH-R in the development and growth of breast tumors. In order to further investigate a possible involvement of b-HCG/LH-R in breast carcinogenesis, immunofluorescence analyses of b-HCG/LH-R expression was performed on 70 preinvasive and adjacent invasive breast cancer specimen using tissue microarrays (TMAs). In 37 preinvasive samples available for further analysis, b-HCG/LH-R was found in 8/37 samples (21.6%; weak, intermediate and strong staining in 4/37 (10.8%), 2/37 (5.4%) and 2/37 (5.4%). In contrast, b-HCG/LH-R expression was observed in 19/27 (70.4%) adjacent invasive specimen with weak, moderate and strong immunostaining in 10/27 (37.0%), 6/27 (22.2%) and 3/27 (11.1%), respectively. This was statistically significant when compared to preinvasive components (P = 0.001, Chi Square Test). Based on the observation that b-HCG/LH-R was found to be selectively upregulated in invasive tumor components, we suggest that under certain circumstances, sensitivity of ductal cells to hormones that target b-HCG/LH-R could favour mammary carcinogenesis.