N-myc downstream-regulated gene 1 (NDRG1), also termed Cap43, Drg1, RTP/rit42, and Proxy-1, is a member of the NDRG family, which is composed of four members (NDRG1-4) that function in growth, differentiation, and cell survival. NDRG1 is ubiquitously expressed and highly responsive to a variety of stress signals including DNA damage, hypoxia, and elevated levels of nickel and calcium. Expression of NDRG1 is elevated in N-myc defective mice and is negatively regulated by N- and c-myc. During DNA damage, NDRG1 is induced in a p53-dependent fashion and is necessary for p53-mediated apoptosis. Research studies have shown that NDRG1 may also play a role in cancer progression by promoting differentiation, inhibiting growth, and modulating metastasis and angiogenesis.
