Oncogenes and tumor suppressors in the molecular pathogenesis of acute promyelocytic leukemia

Abstract

Acute promyelocytic leukemia (APL) is associated with reciprocal chromosomal translocations always involving the retinoic acid receptor α (RARα) gene on chromosome 17 and variable partner genes (X genes) on distinct chromosomes. RARα fuses to the PML gene in the vast majority of APL cases, and in a few cases to the PLZF, NPM, NuMA and Stat5b genes, respectively, leading to the generation of RARα–X and X–RARα fusion genes. Both fusion proteins can exert oncogenic functions through their ability to interfere with the activities of X and RARα proteins. Here, it will be discussed in detail how an extensive biochemical analysis as well as a systematic in vivo genetic approach in the mouse has allowed the definition of the multiple oncogenic activities of PML–RARα, and how it has become apparent that this oncoprotein is able to impair RARα at the transcription level and the tumor suppressive function of the PML protein.