title: CR-LAAO antileukemic effect against Bcr-Abl(+) cells is mediated by apoptosis and hydrogen peroxide.
abstract: Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by the presence of the Bcr-Abl tyrosine kinase protein, which confers resistance to apoptosis in leukemic cells. Tyrosine kinase inhibitors (TKIs) are effectively used to treat CML; however, CML patients in the advanced (CML-AP) and chronic (CML-CP) phases of the disease are usually resistant to TKI therapy. Thus, it is necessary to seek for novel agents to treat CML, such as the enzyme l-amino acid oxidase from Calloselasma rhodostoma (CR-LAAO) snake venom. We examined the antitumor effect of CR-LAAO in Bcr-Abl(+) cell lines and peripheral blood mononuclear cells (PBMC) from healthy subjects and CML patients. CR-LAAO was more cytotoxic towards Bcr-Abl(+) cell lines than towards healthy subjects' PBMC. The H2O2 produced during the enzymatic action of CR-LAAO mediated its cytotoxic effect. The CR-LAAO induced apoptosis in Bcr-Abl(+) cells, as detected by caspases 3, 8, and 9 activation, loss of mitochondrial membrane potential, and DNA damage. CR-LAAO elicited apoptosis in PBMC from CML-CP patients without TKI treatment more strongly than in PBMC from healthy subjects and TKI-treated CML-CP and CML-AP patients. The antitumor effect of CR-LAAO against Bcr-Abl(+) cells makes this toxin a promising candidate to CML therapy.
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: sandra_burin@yahoo.com.br.
authors.forename: Sandra Mara
authors.initials: SM
authors.lastname: Burin
authors.affiliation: Department of Biology, University of Konstanz, Konstanz, Germany. Electronic address: Sandro.Ghisla@uni-konstanz.de.
authors.forename: Sandro
authors.initials: S
authors.lastname: Ghisla
authors.affiliation: Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: amanda.tomie@yahoo.com.br.
authors.forename: Amanda Tomie
authors.initials: AT
authors.lastname: Ouchida
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: afaissa@gmail.com.
authors.forename: Alexandre Ferro
authors.initials: AF
authors.lastname: Aissa
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: gabrielaberzoti@usp.br.
authors.forename: Maria Gabriela Berzoti
authors.initials: MG
authors.lastname: Coelho
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: tassiarc@fcfrp.usp.br.
authors.forename: Tássia Rafaella
authors.initials: TR
authors.lastname: Costa
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: anafarma_usp@yahoo.com.br.
authors.forename: Ana Paula Zambuzi Cardoso
authors.initials: AP
authors.lastname: Marsola
authors.affiliation: Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: bpsimoes@gmail.com.
authors.forename: Belinda
authors.initials: B
authors.lastname: Pinto-Simões
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: lusania@fcfrp.usp.br.
authors.forename: Lusânia Maria Greggi
authors.initials: LM
authors.lastname: Antunes
authors.affiliation: Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: ccurti@usp.br.
authors.forename: Carlos
authors.initials: C
authors.lastname: Curti
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: suvilela@usp.br.
authors.forename: Suely Vilela
authors.initials: SV
authors.lastname: Sampaio
authors.affiliation: Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, SP, Brazil. Electronic address: castrofa@fcfrp.usp.br.
authors.forename: Fabíola Attié
authors.initials: FA
authors.lastname: de Castro
mesh_terms: D000328:Adult; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D003435:Crotalid Venoms / Q000201:enzymology*; D004249:DNA Damage; D004347:Drug Interactions; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D016044:Fusion Proteins, bcr-abl / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D050830:L-Amino Acid Oxidase / Q000494:pharmacology* / Q000627:therapeutic use; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008875:Middle Aged; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors
chemical_list: D000970:Antineoplastic Agents; D003435:Crotalid Venoms; D047428:Protein Kinase Inhibitors; D006861:Hydrogen Peroxide; D050830:L-Amino Acid Oxidase; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl; D020169:Caspases
keywords: Apoptosis; CR-LAAO; Calloselasma rhodostoma; Chronic myeloid leukemia; Tyrosine-kinase inhibitors; l-Amino acid oxidase