Song et al. [95] showed that NPAS2 was up-regulated in AML patients compared to controls, and that NPAS2 knockdown in AML cells led to cell cycle arrest at the G1 and G2 phases, as well as apoptosis in leukemic cells, which may suggest the participation of this gene in the development of leukemia, demonstrating its possible role as biomarker of the disease. The gene discussed is NPAS2; the disease is acute myeloid leukemia.