Several pathways have been associated with tumour progression including the phosphoinositide-3 kinase (PI3K)/serine/threonine-specific protein kinase (Akt) and the Ras/extracellular-signal-related kinase (ERK) pathway (also known as the Ras-Raf-MEK-ERK pathway). The gene discussed is MAPK1; the disease is neoplasm.