A new generation of proto-oncogenes: cold-inducible RNA binding proteins

This review focuses on the roles of two major cold-inducible RNA binding proteins known in human cells: CIRP and RBM3. Both proteins were discovered when they were shown to be induced after exposure to a moderate cold-shock and other cellular stresses such as UV radiation and hypoxia. Initially, it was suggested that these proteins have a suppressive rather stimulatory effect on proliferation; however, proliferative and/or proto-oncogenic functions have recently been assigned to CIRP and RBM3. In a high throughput genetic screen, we recently identified CIRP as an immortalized gene in murine primary cells. On the other hand, the role of RBM3 in transformation has already been demonstrated. Interestingly, both CIRP and RBM3 have been found to be up-regulated in human tumors. This article highlights the roles of CIRP and RBM3 in tumorigenesis, and proposes a model by which CIRP might contribute to senescence bypass by counteracting the deleterious effects of oxidative damage.