aetiopathogenetic role protooncogene role A role played by the oncogene that is altered forms of normal cellular genes. Many proto-oncogenes are homologous to viral oncogenes and involved in the control of cell proliferation or differentiation. Mutations, amplifications or rearrangements of proto-oncogenes lead to upregulated or deregulated cell growth and allow them to function as oncogenes. Normal cellular genes at a stage prior to carcinogenesis. The products of proto-oncogenes are important regulators of biological processes and appear to be involved in the events that serve to maintain the ordered procession through the cell cycle. Proto-oncogenes have names of the form c-onc. http://purl.bioontology.org/ontology/MESH/D011519 http://purl.bioontology.org/ontology/SNOMEDCT/1496005