oncoprotein

noun

on·​co·​pro·​tein ˌäŋ-kō-ˈprō-ˌtēn, ˌän-, -ˈprōt-ē-ən 

: a protein that is coded for by a viral oncogene which has been integrated into the genome of a eukaryotic cell and that is involved in the regulation or synthesis of proteins linked to tumorigenic cell growth