title: Phorbol ester induces abnormal chronic lymphocytic leukemia cells to express features of hairy cell leukemia.
abstract: We have investigated the relationship between chronic lymphocytic leukemia (CLL), hairy cell leukemia (HCL), and different normal B cell subsets: Mrbc+, T1+ and slgM+ tonsil cells; germinal center; mantle zone; and peripheral blood B lymphocytes. Both malignant and normal cells were incubated in vitro with the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) for 72 hours and the morphology, cytochemical profile, and surface markers were evaluated. The results show that CLL cells TPA-induced become indistinguishable from HCL by four independent criteria: the morphology; the cytoplasmic tartrate resistant acid phosphatase (TRAP) enzyme activity; the membrane positivity with anti-Leu M5 (SHCL3); and anti-Tac monoclonal antibodies which, in the uninduced state, react only with HCL. The features of TRAP and Tac positivity are also expressed (though in variable degree) by different normal B cell populations activated with TPA or pokeweed mitogen (PWM). It is concluded that HCL might represent an aberrantly activated variant of CLL (or of a CLL-related disorder).
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000368:Aged; D001402:B-Lymphocytes / Q000145:classification; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D054278:Embryonal Carcinoma Stem Cells; D006801:Humans; D007943:Leukemia, Hairy Cell / Q000097:blood*; D007945:Leukemia, Lymphoid / Q000473:pathology; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D008934:Mitogens / Q000494:pharmacology; D014411:Neoplastic Stem Cells / Q000187:drug effects; D010703:Phorbol Esters / Q000494:pharmacology*
chemical_list: D008934:Mitogens; D010703:Phorbol Esters; D000135:Acid Phosphatase