CDKN2A and metastatic neoplasm: Although this entire developmental process is multifactorial and requires additional mutations, epigenetic alterations associated with changes in the expression in tumor suppressors (e.g., Trp53, Cdkn2a) and EMT-related transcription factors, primary and metastatic tumor cells with mesenchymal characteristics were dependent on the persistent expression of oncogenic RAS for tumor cell growth and survival in vivo.