CDKN2A and neoplasm: It was demonstrated (Stransky et al. 2011; Agrawal et al. 2011) that HPV positive tumours accumulated far fewer mutations than HPV negative ones especially within TP53, CDKN2A, PTEN, PIK3CA, FBXW7, HRAS and NOTCH1 genes, what influenced the functioning of key cellular signalling pathways including EGFR/PI3K/AKT/mTOR.