Vol 7, No 4 (2016)
Review paper
Published online: 2017-04-07

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Molecular pathogenesis of chronic lymphocytic leukemia

Emilia Białopiorowicz, Przemysław Juszczyński
Hematologia 2016;7(4):273-286.


Chronic lymphocytic leukemia (CLL) is the most common type of adult leukemia, characterized by accumulation of mature but functionally incompetent clonal B lymphocytes in peripheral blood, bone marrow and lymphoid tissues. The clinical course of CLL varies from patients with indolent, stable disease to those with aggressive leukemia who succumb to their disease in a short time. The use of novel molecular biology techniques revealed genetic and epigenetic heterogeneity among CLL patients and allowed to define novel somatic mutations of prognostic value. The CLL genome and epigenome undergo dynamic changes during disease course due to clonal evolution, which leads to selection and expansion of leukemic clones with the highest survival potential. This review focuses on the key aspects of CLL molecular pathogenesis including genetic and epigenetic alterations, B-cell signaling and the role of tumor microenvironment. Progress in the understanding of CLL biology will help to develop more accurate prognostication models and enable more personalized patient treatment in the future.

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