The cervical malignant cells display a down regulation of ER-α but retain the ER-β expression

• Published in: International journal of clinical and experimental pathology Vol. 6; no. 8; pp. 1594 - 1602
• Main Authors: López-Romero, Ricardo, Garrido-Guerrero, Efraín, Rangel-López, Angélica, Manuel-Apolinar, Leticia, Piña-Sánchez, Patricia, Lazos-Ochoa, Minerva, Mantilla-Morales, Alejandra, Bandala, Cindy, Salcedo, Mauricio
• Format: Journal Article
• Language: English
• Published: United States e-Century Publishing Corporation 01.01.2013
• Subjects: Biomarkers, Tumor - analysis; Biomarkers, Tumor - genetics; Carcinoma, Squamous Cell - genetics; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - pathology; Down-Regulation; Estrogen Receptor alpha - analysis; Estrogen Receptor alpha - biosynthesis; Estrogen Receptor alpha - genetics; Estrogen Receptor beta - analysis; Estrogen Receptor beta - biosynthesis; Estrogen Receptor beta - genetics; Female; Humans; Immunohistochemistry; Original; Reverse Transcriptase Polymerase Chain Reaction; Uterine Cervical Neoplasms - genetics; Uterine Cervical Neoplasms - metabolism; Uterine Cervical Neoplasms - pathology; ER-α; ER-β; cervical cancer; HPV
• ISSN: 1936-2625

The human cervix is a tissue target of sex steroid hormones as estradiol (E2) which exerts its action through of the estrogen receptors alpha and beta (ER-α and ER-β). In this study we investigated the expression of ER-α and ER-β in human invasive cervical carcinomas using immunohistochemistry and RT-PCR analyses and compared with that observed in the corresponding normal tissue. The results show nuclear expression of ER-α mainly in the first third of normal cervical epithelium, however, decreased or absent expression were present in invasive cervical carcinoma, indicating that expression of ER-α is lost in cervical cancer. Nevertheless, by RT-PCR we were able to demonstrate mRNA expression of ER-α in invasive cervical tissues. These results suggest that loss of ER-α could be due to a mechanism of post-transcriptional and/or post-translational regulation of its gene during the progression to invasive carcinoma. On the other hand, ER-β was expressed in normal cervix with an expression pattern similar to ER-α. In addition to its nuclear localization, cytoplasmic immunoreaction of ER-β was present in the epithelium of invasive cervical carcinomas, suggesting an association between cytoplasmic ER-β expression and invasive phenotype in the cervical tumors. In summary, the results show that the cervical malignant cells tend to loss the ER-α but maintain the ER-β actively expressed. Loss of expression of ER-α in neoplastic tissue suggests that the estrogenic effects could be conducted through the ER-β in human neoplastic cervical tissue. More detailed studies are needed to confirm this suggestion and to determine the role of ER-β in cervical cancer.