To further investigate this apparent paradox of enhanced steroidogenic potential in ACC cells expressing an adrenocortical stem cell marker, four different human ACC cell lines (H295R, MUC‐1, TVBF7 and CU‐ACC1) and one mouse ACC cell line (BCH‐ACC3A) were cultured as spheroids. This evidence concerns the gene MUC1 and adrenal cortex carcinoma.