Aim
To assess the utility of AGR2 as a prognostic marker in EC.
Background
Biomarkers for identification of endometrial cancers (ECs) with high risk of recurrence are required to reduce the rising EC-related mortality. AGR2 is a prognostic marker in several hormonally-regulated cancers.
Conclusions
AGR2 is overexpressed in low grade ECs and positively associated with hormone receptors. The association between high AGR2 and progressive disease within the high-ERα-expressing ECs suggests that in this group of patients, AGR2 might be a potential biomarker of poor prognosis.
Methods
AGR2 immunoexpression was evaluated in 163 human endometrial samples. Change in AGR2 mRNA levels in response to oestrogen and dihydrotestosterone was studied in vitro.
Results
Upregulation of AGR2 (protein and mRNA) was seen in low grade EC, compared to the postmenopausal endometrium (P = 0.013) and to the high-grade EC (P < 0.0001). Elevated AGR2 protein expression-scores were associated with a high expression of estrogen alpha (ERα), progesterone, androgen receptors and early clinical stages. Metastatic lesions maintained higher AGR2 expression relative to matched-primary tumors. High-AGR2 protein levels were associated with better overall survival (P = 0.02) in all ECs, but in highly-ERα-expressing ECs, AGR2 associated with unfavourable patient outcome. Androgen through its receptor, downregulated AGR2 mRNA in the Ishikawa cells. Conclusions: AGR2 is overexpressed in low grade ECs and positively associated with hormone receptors. The association between high AGR2 and progressive disease within the high-ERα-expressing ECs suggests that in this group of patients, AGR2 might be a potential biomarker of poor prognosis.