At the beginning, we uploaded raw qPCR data for candidate reference (HPRT1, PGK1, RPS23, SNRPA; set 1) and target (B4GALT1–B4GALT7) genes (Supplementary Table S1) as well as quantified qPCR data for candidate reference genes (Supplementary Table S2) obtained for five human cell lines (melanocytes and melanoma cells from different stages of oncogenic progression) comprising the experimental model. Here, HPRT1 is linked to melanoma.