Expression of Evi-1 Gene in Leukaemia: Diagnostic and Prognostic Perspective

Abstract

Leukaemias are malignant neoplasms characterized by disorderly, purposeless proliferation of white blood cells with abundance of one cell type. The exact aetiology of leukaemias is still yet to be fully understood. However, it is generally believed that neoplasm is caused by genetic mutation, chromosomal translocation, or activation of certain oncogenes. There are also nuclear oncogenes which are also vital genes in normal cell proliferation and differentiation, often being pivotal genes in developmental and cell cycle regulation. They are also important in cancer progression. Ecotropic viral integration site (EVI-1), a nuclear oncogene has been implicated in the progression of some leukaemias. EVI-1 gene is located on the human chromosome 3 band q24-q28 and spans over 100 kb. The EVI-1 gene encodes a 145 kDa protein of the zinc-finger family which is an essential transcription factor for appropriate murine and human development and is also associated with some leukaemias, following ectopic expression. EVI-1 protein is divided into two main regions: The N-terminal region that contains zinc finger domains (ZFi) and C-terminal region containing three zinc finger domains (ZFii) and a sequence of acidic amino acid. This review summarizes the biological, leukaemogenetic/oncogenic roles and biochemical properties of EVI-1. It further discusses the diagnostic and prognostic implication of EVI-1 in some leukaemias, encouraging incorporation of routine assay of EVI-1 in diagnosis and prognostic monitoring of leukaemias.