Final answer:
When an oncogene is lost or overactive, it can lead to uncontrolled cell division and cancer. For example, overexpression of the oncogene myc is associated with Burkett's Lymphoma.
Step-by-step explanation:
When an oncogene is lost or overactive, it can have significant effects on cell growth and division, potentially leading to the development of cancer. A malfunctioning or overactive oncogene can promote uncontrolled cell division, even in situations where it is not desirable. On the other hand, a dysfunctional tumor suppressor gene may fail to provide the necessary stop signal, also resulting in unwanted cell division and proliferation. For example, the overexpression of the oncogene myc is associated with Burkett's Lymphoma, where it transforms normal B cells into cancerous cells that continue to grow uncontrollably.