Malignant conversion The transformation of a preneoplastic cell into that expresses the malignant phenotype Further genetic changes Reversible The further genetic changes may result from infidelity of DNA synthesis May be mediated through the activation of proto-oncogene and inactivation of tumor suppressor gene15 Malignant conversion • The transformation of a preneoplastic cell into that expresses the malignant phenotype • Further genetic changes • Reversible • The further genetic changes may result from infidelity of DNA synthesis • May be mediated through the activation of proto-oncogene and inactivation of tumor￾suppressor gene