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Int J Clin Exp Pathol 2013;6(8):1594-1602

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

Ricardo López-Romero, Efraín Garrido-Guerrero, Angélica Rangel-López, Leticia Manuel-Apolinar, Patricia Piña-Sánchez, Minerva Lazos-
Ochoa, Alejandra Mantilla-Morales, Cindy Bandala, Mauricio Salcedo

Laboratorio de Oncología Genómica, Unidad de Investigación Médica en Enfermedades Oncológicas, Hospital de Oncología, Centro Médico
Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México D.F.; Departamento de Genética y Biología Molecular, CINVESTAV-IPN, México
D.F.; Unidad de Investigación Médica en Enfermedades Nefrológicas, Hospital de Especialidades, Centro Médico Nacional SXXI, Instituto
Mexicano del Seguro Social, Mexico D.F.; Unidad de Investigación Médica en Enfermedades Endócrinas, Hospital de Especialidades, Centro
Médico Nacional SXXI, Instituto Mexicano del Seguro Social, Mexico D.F.; Departamento de Patología, Hospital General de México, SS. Mexico
D.F.; Departamento de Patología, Hospital de Oncología, Centro Médico Nacional SXXI, Instituto Mexicano del Seguro Social, Mexico D.F.;
Unidad de Apoyo a la Investigación, Instituto Nacional de Rehabilitación, Secretaría de Salud. These authors contributed equally to this work.

Received June 4, 2013; Accepted June 19, 2013; Epub July 15, 2013; Published August 1, 2013

Abstract: 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. (IJCEP1304003).

Keywords: ER-α, ER-β, cervical cancer, HPV

Address correspondence to: Dr. Mauricio Salcedo, Laboratorio de Oncología Genómica, Unidad de Investigación Médica en Enfermedades
Oncológicas, Hospital de Oncología, CMN SXXI-IMSS. Av. Cuauhtémoc 330, Col. Doctores, México, Distrito Federal 06720, México. Phone: 55-
56276900 Ext. 22706; E-mail: maosal89@yahoo.com