hLH/hCG-receptor expression correlates with in vitro invasiveness in human primary endometrial cancer

OBJECTIVE: Endometrial cancer (EC) is the most frequent cancer of the female genital tract. It has been hypothesized that those ECs that occur in the postmenopausal period, might be sensitive to elevated levels of luteinizing hormone/human chorionic gonadotropin (LH/hCG). Based on previous indications, we analyzed the functional expression of LH/hCG receptors (LH/hCG-R) in primary ECs. METHODS: We studied a cohort of primary ECs, in which both the LH/hCG-R mRNA and the LH/hCG-R protein were analyzed. Results were correlated with both clinical-pathological data and the effects of LH addition on cell invasion in vitro. RESULTS: The LH/hCG-R mRNA levels ranged from 4.67 e(-02) to 2.36 e(+03). The transcript was properly translated into a functional LH/hCG-R protein. The analysis of cell invasion in vitro in response to LH/hCG allowed us to divide the EC samples into two groups, one with a null or very low response (non-responders=NR) and the other with a significant response to LH (responders=R). The two groups had significantly different levels of LH/hCG-R mRNA expression: the NR group had a median value of 1.40 e(+)(00), while the R group of 7.42 e(+)(01) (p=0.043). CONCLUSION: In primary ECs a statistically significant correlation emerged between the levels of LH/hCG-R mRNA and the LH-induced cell invasion in vitro. These results suggest that therapies aimed at decreasing LH levels, through Gonadotropin Releasing Hormone (Gn-RH) analogues, could produce benefits in the treatment of recurrent or metastatic EC, especially in patients displaying high LH/hCG-R levels.