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

Abstract

Introduction: 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.

Material and methods: 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).

Results: 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).

Conclusions: 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.

Fig. 1

a, b Immunofluorescence for b-HCG/LH-R lacking receptor expression in ductal components of patients with DCIS (a ×200, b ×400)

Fig. 2

a, b Immunofluorescence for b-HCG/LH-R exhibiting strong staining intensity in ductal components of patients with DCIS (a ×200, b ×400)

Fig. 3

a, b Immunofluorescence for b-HCG/LH-R lacking receptor expression in ductal components of patients with adjacent IBC (a ×200, b ×400)

Fig. 4

a, b Immunofluorescence for b-HCG/LH-R exhibiting strong staining intensity in ductal components of patients with adjacent IBC (a ×200, b ×400)

Fig. 5

Immunofluorescence for b-HCG/LH-R: absence of specific staining in negative control slide. For primary antibody used see “Materials and methods” (×400)