Microobiologia

Expression of Follicle-Stimulating Hormone Receptor in Tumor Blood Vessels

Background
In adult humans, the follicle-stimulating hormone (FSH) receptor is expressed only in the granulosa cells ofthe ovary and the Sertoli cells of the testis. It is minimally expressed by the endothelial cells of gonadal blood vessels.

Methods
We used immunohistochemical and immunoblotting techniquesinvolving four separate FSH-receptor-specific monoclonal antibodies that recognize different FSH receptor epitopes and in situ hybridization to detect FSH receptor in tissue samples from patients with awide range of tumors. Immunoelectron microscopy was used to detect FSH receptor in mouse tumors.

Results
In all 1336 patients examined, FSH receptor was expressed by endothelial cells in tumors ofall grades, including early T1 tumors. The tumors were located in the prostate, breast, colon, pancreas, urinary bladder, kidney, lung, liver, stomach, testis, and ovary. In specimens obtained duringsurgery performed to remove tumors, the FSH receptor was not expressed in the normal tissues located more than 10 mm from the tumors. The tumor lymphatic vessels did not express FSH receptor. Theendothelial cells that expressed FSH receptor were located at the periphery of the tumors in a layer that was approximately 10 mm thick; this layer extended both into and outside of the tumor.Immunoelectron microscopy in mice with xenograft tumors, after perfusion with anti–FSH-receptor antibodies coupled to colloidal gold, showed that the FSH receptor is exposed on the luminal endothelial surface andcan bind and internalize circulating ligands.

Conclusions
FSH receptor is selectively expressed on the surface of the blood vessels of a wide range of tumors. (Funded by INSERM.)

AntecedentesEnlos humanos adultos, la hormona folículo-estimulante (FSH) del receptor se expresa solamente en las células de la granulosa del ovario y las células de Sertoli de los testículos. Es mínimamente...