IL-13R[alpha]2 gene expression is a biomarker of adverse outcome in patients with adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare but aggressive endocrine malignancy that usually results in a fatal outcome. To allow the better clinical management and reduce mortality, we searched for clinical and molecular markers that are reliable predictor of disease severity and clinical outcome in ACC patients. We determined a correlation between the overexpression of IL-13R[alpha]2 and the clinical outcome in ACC patients using comprehensive data available in The Cancer Genome Atlas (TCGA) database. The dataset of 79 ACC subjects were divided into groups of low, medium, or high expression of IL-13R[alpha]2 as determined by RNA-seq. These patients were also stratified by length of survival, overall survival, incidence of a new tumor event, incidence of metastasis, and production of excess hormones. We report a correlation between IL-13R[alpha]2 expression and survival of subjects with ACC. High expression of IL-13R[alpha]2 in ACC tumors was significantly associated with a lower patient survival rate and period of survival compared to low expression (p = 0.0084). In addition, high IL-13R[alpha]2 expression was significantly associated with a higher incidence of new tumor events and excess hormone production compared to low or medium IL-13R[alpha]2 expression. Within the cohort of patients that produced excess hormone, elevated IL-13R[alpha]2 expression was significantly associated with a lower survival rate. Additionally, IL-13R[alpha]1 had a potential relationship between transcript level and ACC survival. Our results and promising antitumor activity in preclinical models and trials indicate that IL-13R[alpha]2 expression is an important prognostic biomarker of ACC disease outcome and a promising target for therapeutic treatment of ACC.