Immunolabelling of the inhibin/activin-βC subunit in normal and malignant human uterine cervical tissue and cervical cancer cell lines.

Inhibins are dimeric glycoproteins, composed of an α-subunit and one of two possible β-subunits (βA or βB), with substantial roles in human reproduction and in endocrine-responsive tumours. Recently a novel β subunit named βC was described, although it is still unclear if normal or cancerous cervical epithelial cells as well as cervical cancer cell lines can synthesise the inhibin-βC subunit. Four normal cervical tissue samples together with specimens of well-differentiated squamous cervical cancer and adenocarcinoma of the cervix were immunohistochemically analyzed. Additionally, two cervical carcinoma cell lines (HeLa and CaSKi) were analyzed by immunofluorescence for the expression of this novel subunit. We demonstrated for the first time an immunolabelling of the inhibin-βC subunit in normal and malignant cervical tissue, as well as cervical cancer cells. Although the physiological role is still unclear in cervical tissue, the inhibin-βC subunit might play important roles in carcinogenesis. Moreover, the synthesis of this subunit in cervical carcinoma cell lines of squamous and epithelial origins allows the use of these cell lines in elucidating its functions in cervical pathogenesis.