Angiogenesis and lymphangiogenesis in primary cutaneous T-cell lymphomas

Abstract

Primary cutaneous T-cell lymphomas are a group of rare hematologic malignancies, derived from mature T lymphocytes and initially developing only in the skin. The most common lymphomas representing this group are mycosis fungoides and Sezary syndrome. Mycosis fungoides is an indolent disease with a chronic course and characteristic evolution of the skin lesions from erythematous patches, through plaques to tumors. Sezary syndrome is characterized by an aggressive course and a triad of symptoms (erythroderma, generalized lymphadenopathy, and the presence of atypical cells in the skin, lymph nodes and peripheral blood). The etiopathogenesis of cutaneous lymphomas is not fully understood, but a few studies on angiogenesis and lymphangiogenesis in these malignancies indicate a significant role in their development and progression. Angiogenesis is a process of formation of new blood vessels from existing ones. Lymphangiogenesis is a similar process concerning lymphatic vasculature. Development of new vessels is a complex process composed of several successive stages: migration, proliferation, and differentiation of endothelial cells, extracellular matrix degradation and formation and stabilization of new vessels, regulated by growth factors, cytokines and other proteins. Both phenomena are essential in the development and progression of solid tumors and hematological malignancies. Therapeutic strategies involving the inhibition of tumor angiogenesis and lymphangiogenesis are a promising new direction of studies in antitumor therapy, requiring further experiments.