ACTB and melanoma: In order to further strengthen the transcriptomic analysis results, the differential expression of six DEGs (APOE, GAPDH, ACTB, RNA28S1N5, RPL31, and RPS17), selected on the basis of the most relevant fold changes and p-values emerging from the microarray experiments, was further assessed by RT-qPCR in a small subset of melanoma samples from the microarray analysis cohort (as described in the relative Section 4).