Only, in one study, overexpression of inhibitors of apoptosis proteins, including BIRC6, cIAP1, cIAP2, XIAP, Livin, and Survivin, was evaluated in 49 patients with ACC, and the results reported zero overexpression of BIRC6 in the studied cases [ 17]. This evidence concerns the gene BIRC2 and adrenal cortex carcinoma.