Pathogenesis of lymphoid malignancies

Abstract

Lymphocyte development is a complex and multistep process that leads to generation of a repertoire of cells endowed with specific receptors and capable of recognizing and responding to antigens. The B- (BCR) and T-cell (TCR) receptors are generated as a result of immunoglobulin or TCR gene re­arrangements that involve DNA double strand breaks. The DNA editing processes occurring in de­veloping lymphocytes predispose cells to primary translocations and oncogenic mutations, followed by additional aberrations accumulating in the background of these primary lesions. Arising typical, recurrent genetic abnormalities are a diagnostic feature of certain lymphoid malignancies. Genetic and epigenetic lesions accumulating within cells lead to deregulated signaling pathways and un­controlled cell proliferation, resistance to apoptosis and metabolic changes. Transformed cells retain some features of their normal counterparts, such as reliance on tonic BCR signaling and signals delivered by microenvironment. In the current manuscript, we provide a concise review of common pathogenic mechanisms in lymphoid tumors and their biological implications.