Significance of Inactivated Genes in Leukemia: Pathogenesis and Prognosis

Document Type : Review Article

Authors

1 Health Research Institute, Thalassemia and Hemoglobinopathy Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

2 Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran

3 Signal Transduction Unit, Department of Surgery, Medicine, Dentistry and Morphology, University of Modena and Reggio Emilia, Modena, Italy

Abstract

Epigenetic and genetic alterations are two mechanisms participating in leukemia, which can
inactivate genes involved in leukemia pathogenesis or progression. The purpose of this review
was to introduce various inactivated genes and evaluate their possible role in leukemia pathogenesis
and prognosis. By searching the mesh words “Gene, Silencing AND Leukemia” in
PubMed website, relevant English articles dealt with human subjects as of 2000 were included
in this study. Gene inactivation in leukemia is largely mediated by promoter’s hypermethylation
of gene involving in cellular functions such as cell cycle, apoptosis, and gene transcription.
Inactivated genes, such as ASPP1, TP53, IKZF1 and P15, may correlate with poor prognosis
in acute lymphoid leukemia (ALL), chronic lymphoid leukemia (CLL), chronic myelogenous
leukemia (CML) and acute myeloid leukemia (AML), respectively. Gene inactivation may play
a considerable role in leukemia pathogenesis and prognosis, which can be considered as
complementary diagnostic tests to differentiate different leukemia types, determine leukemia prognosis, and also detect response to therapy. In general, this review showed some genes inactivated only in leukemia (with differences between B-ALL, T-ALL, CLL, AML and CML). These differences could be of interest as an additional tool to better categorize leukemia types. Furthermore; based on inactivated genes, a diverse classification of Leukemias could represent a powerful method to address a targeted therapy of the patients, in order to minimize side effects of conventional therapies and to enhance new drug strategies.

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