RARRES2 and adrenal cortex carcinoma: Levels of serum retinoic acid receptor responder protein 2 (RARRES2), known as chemoattractant and adipokine and, according to recent findings, a tumor suppressor by promoting β-catenin phosphorylation/degradation and inhibiting p38 phosphorylation in adrenocortical carcinoma, is elevated in patients with ACC.