It was published that the level of phosphorylated PKM2 variant Tyr105 is dependent on the activity of growth factor receptors [26,27], so we chose the HNSCC cell line with the highest variant level, Detroit-562, for investigating the influence of the growth factors epidermal growth factor (EGF), fibroblast growth factor 2 (FGF2) and hepatocyte growth factor (HGF) on phosphorylation. This evidence concerns the gene PKM and head and neck squamous cell carcinoma.