Effects of vemurafenib and trametinib on viability, cell cycle, percentages of Ki-67high (intensively proliferating) and CD271high (stem-like) melanoma cells and activity of signaling pathways crucial for melanoma development and maintenance, including the RAF/MEK/ERK pathway, WNT/β-catenin pathway and NF-κB signaling were very similar irrespective of growth conditions, at least within the first 72 h of treatment. This evidence concerns the gene NFKB1 and melanoma.