Expression of Estrogen Receptors in OSCC in Relation to Histopathological Grade

Estrogen receptor (ER)-mediated pathways are involved in the pathogenesis of several tumors. Preliminary studies have demonstrated a significant effect of ER agonists and antagonists on oral squamous cell carcinoma (OSCC) cell lines. Recent results suggest that ER subtype-specific expression patterns might depend on the grade of differentiation of OSCC. Therefore, the aim of the present study was to evaluate the expression of ERα and ERβ in OSCC and its correlation to histological tumor grade and gender.

Tumor sections of 25 patients (13 males and 12 females) retrieved from OSCC databases with two different histological gradings (well-differentiated, poorly differentiated) were evaluated. The detection of ERα and ERβ expression in tumor cells and corresponding healthy mucosa adjacent to tumor was performed using immunohistochemistry.

Well-differentiated OSCC showed no significant difference between the expression of ERβ in tumor cells and corresponding mucosa. In poorly-differentiated OSCC the expression of ERβ was significantly higher in tumor cells than in corresponding mucosa. In patients without regular alcohol and/or nicotine abuse, there was no significant difference of ERβ expression in OSCC compared to corresponding healthy mucosa in contrast to patients having these risk factors. Expression of ERα was found in one tumor.

ERβ is the predominant ER sub-type expressed significantly higher in poorly-differentiated OSCC tumors compared to healthy mucosa adjacent to the tumor. Different expression patterns in relation to histological grade might suggest an influential role of ERβ in tumor (de-) differentiation of OSCC.