A recent study by Speigl and co-authors analyzed putative CSC markers (ALDH1A1, ABCG2, CD44v7/8, CD44v10, CD133, CD271, and Nestin) in melanoma and revealed widespread expression across cell lines, early-passage strains, and patient tissues, suggesting limited specificity for CSCs. Here, ALDH1A1 is linked to melanoma.