title: Danazol induces apoptosis and cytotoxicity of leukemic cells alone and in combination with purine nucleoside analogs in chronic lymphocytic leukemia.
abstract: Recently, great progress has been achieved in the treatment of chronic lymphocytic leukemia (CLL). However, some patients, particularly older patients with comorbidities or with relapsed/refractory leukemia, still have limited therapeutic options. There is an urgent need to discover less toxic and more effective drugs for CLL patients. Applying new modalities or substances that are widely used for the treatment of other diseases has been reported to improve results in CLL treatment. This study aimed to assess the non-chemotherapeutic drug danazol for its potential to destroy leukemic cells. Leukemic cells, obtained from the peripheral blood and bone marrow of 23 CLL patients, were cultured in the presence of danazol and its combination with the purine nucleoside analogs fludarabine and cladribine and bendamustine. After 24 h of incubation, the rate of apoptosis indicated by active caspase-3 expression, and cytotoxicity indicated by forward light scatter and light scatter analysis, was assessed by flow cytometry. We also measured expression of apoptosis-regulating proteins of BCL family and active caspase 9 and active caspase 8 expressions in leukemic cells. Danazol had a caspase-dependent pro-apoptotic and cytotoxic effect on leukemic cells in a tumor-specific manner. The mechanisms of its action appear to be complex and should be precisely established; however, induction of apoptosis involving both mitochondrial and receptor cascades appears to be most probable. Danazol showed a synergic effect with cladribine, an additive effect with fludarabine, and an infra-additive effect with bendamustine. The rate of danazol-induced apoptosis and cytotoxicity did not differ between patients with better and worse prognostic markers. Our results indicate that danazol may be a potential therapeutic agent for CLL patients alone and in combination with purine analogs.
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland. monika.podhorecka@onet.pl.
authors.forename: Monika
authors.initials: M
authors.lastname: Podhorecka
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland.
authors.forename: Arkadiusz
authors.initials: A
authors.lastname: Macheta
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland.
authors.forename: Sylwia
authors.initials: S
authors.lastname: Chocholska
authors.affiliation: Department of Clinical Immunology, Medical University of Lublin, Lublin, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Bojarska-Junak
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Szymczyk
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland.
authors.forename: Aneta
authors.initials: A
authors.lastname: Goracy
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Dmoszynska
authors.affiliation: Department of Haematooncology and Bone Marrow Transplantation, Medical University of Lublin, Staszica 11, 20-081, Lublin, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Hus
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D003603:Cytotoxins / Q000008:administration & dosage*; D003613:Danazol / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011684:Purine Nucleosides / Q000008:administration & dosage* / Q000737:chemistry; D014407:Tumor Cells, Cultured
chemical_list: D003603:Cytotoxins; D011684:Purine Nucleosides; D003613:Danazol
keywords: Apoptosis; Bendamustine; Chronic lymphocytic leukemia; Cladribine; Cytotoxicity; Danazol; Fludarabine