The Expression Of Transcription Factor Boris And Its Association With The Estrogen Receptor Beta (Er-Beta) In Cervical Carcinogenesis

BORIS is a transcription factor aberrantly expressed in human cancers that can regulate the expression of estrogen receptors in endometrial cancer and breast cancer. We evaluated the expression of BORIS and the estrogen receptors alpha (ER-alpha) and beta (ER-beta) in ten cell lines derived from cervical cancer using RT-PCR and Western-blot. We also evaluated 54 cervical tissues: normal epithelia, low-grade intraepithelial lesions (LSIL), high-grade intraepithelial lesions (HSIL), and invasive squamous carcinomas (SC) using immunohistochemistry. In the cell lines, BORIS mRNA and protein expressions are associated with ER-beta expression but not with ER-alpha expression. In the normal cervical epithelium, ER-alpha and ER-beta were expressed but the BORIS protein was not detected. In the LSIL samples, BORIS, ER-alpha and ER-beta were expressed; however, in the HSIL samples, only the BORIS and ER-beta expressions were detected, but ER-alpha expression was minimal or null. In the SC, only BORIS and ER-beta were detected. In summary, the results show that the expressions of BORIS and ER-beta increase while the expression of ER-alpha decreases according to the severity of the lesions. These results suggest synergistic roles for BORIS and ER-beta during cervical cancer progression with a possible regulation of the estrogen receptors by BORIS in the development of cervical cancer; however, more detailed studies are needed to confirm this suggestion and to determine the precise role of BORIS in cervical cancer.