Estrogen receptor-β expression in human laryngeal carcinoma: Correlation with the expression of epithelial-mesenchymal transition specific biomarkers

Laryngeal carcinoma is a malignancy of the respiratory tract with a significantly higher male to female ratio, suggesting involvement of gender-depended factors in the pathogenesis. Estrogen influences the pathological processes of hormone-dependent cancers, such as breast, prostate and ovarian cancers, through its receptors, estrogen receptor-alpha (ER-alpha) and -beta (ER-beta). While ER-alpha promotes cell proliferation, recent studies indicate that ER-alpha is protective against carcinoma progression into an invasive state. However, it is unclear whether ER-beta plays a role in laryngeal cancer. In the present study we examined the expression of ER-beta in 80 invasive human squamous laryngeal carcinomas by immunohistochemistry and correlated ER-beta expression with markers of epithelial-mesenchymal transition (EMT). ER-beta was expressed in 83% of tumour specimens where it was localized in the nuclei of tumour cells. The expression of ER-beta correlated positively with the maintenance of Ecadherin and beta-catenin at cell junctions and negatively with the loss of E-cadherin, nuclear translocation of beta-catenin and increased TNM stage. We concluded that estrogen receptor beta expression is documented in laryngeal cancer indicating a possible role in the pathogenesis of this malignancy. It is suggested that ER-beta could protect tumour cells from acquiring aggressive EMT features such as E-cadherin downregulation and nuclear beta-catenin activation.