C-Myc is an oncogene that functions both in the stimulation of cell proliferation and in apoptosis. c-Myc elicits its oncogenic activity by causing immortalization, and to a lesser extent the transformation of cells, in addition to several other mechanisms. The c-MYC proto-oncogene encodes a transcription factor that is critical for cell growth and proliferation. It is one of the genes frequently altered in cancer cells in which it exhibits constitutive activity. Downregulation of c-Myc is critical for 2-Methoxyestradiol (2ME2)-induced oxidative stress and apoptosis in AML cells. And its up-regulation is important for promoting lymphocyte cell division, and demonstrating that GFP-c-Myc expression is a marker of proliferating lymphocytes in vivo..