title: ANKHD1 silencing inhibits Stathmin 1 activity, cell proliferation and migration of leukemia cells.
abstract: ANKHD1 is highly expressed in human acute leukemia cells and potentially regulates multiple cellular functions through its ankyrin-repeat domains. In order to identify interaction partners of the ANKHD1 protein and its role in leukemia cells, we performed a yeast two-hybrid system screen and identified SIVA, a cellular protein known to be involved in proapoptotic signaling pathways. The interaction between ANKHD1 and SIVA was confirmed by co-imunoprecipitation assays. Using human leukemia cell models and lentivirus-mediated shRNA approaches, we showed that ANKHD1 and SIVA proteins have opposing effects. While it is known that SIVA silencing promotes Stathmin 1 activation, increased cell migration and xenograft tumor growth, we showed that ANKHD1 silencing leads to Stathmin 1 inactivation, reduced cell migration and xenograft tumor growth, likely through the inhibition of SIVA/Stathmin 1 association. In addition, we observed that ANKHD1 knockdown decreases cell proliferation, without modulating apoptosis of leukemia cells, while SIVA has a proapoptotic function in U937 cells, but does not modulate proliferation in vitro. Results indicate that ANKHD1 binds to SIVA and has an important role in inducing leukemia cell proliferation and migration via the Stathmin 1 pathway. ANKHD1 may be an oncogene and participate in the leukemia cell phenotype.
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: João Agostinho
authors.initials: JA
authors.lastname: Machado-Neto
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Mariana
authors.initials: M
authors.lastname: Lazarini
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Patricia
authors.initials: P
authors.lastname: Favaro
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Paula
authors.initials: P
authors.lastname: de Melo Campos
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Renata
authors.initials: R
authors.lastname: Scopim-Ribeiro
authors.affiliation: Integrated Center for Childhood Onco-Hematological Investigation, University of Campinas, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Gilberto Carlos
authors.initials: GC
authors.lastname: Franchi Junior
authors.affiliation: Integrated Center for Childhood Onco-Hematological Investigation, University of Campinas, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Alexandre Eduardo
authors.initials: AE
authors.lastname: Nowill
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Paulo Roberto Moura
authors.initials: PR
authors.lastname: Lima
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Fernando Ferreira
authors.initials: FF
authors.lastname: Costa
authors.affiliation: INSERM U1016, Institut Cochin, Paris, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Benichou
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil.
authors.forename: Sara Teresinha
authors.initials: ST
authors.lastname: Olalla Saad
authors.affiliation: Hematology and Hemotherapy Center-University of Campinas/Hemocentro-Unicamp, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas 13083-878, São Paulo, Brazil. Electronic address: ftraina@fmrp.usp.br.
authors.forename: Fabiola
authors.initials: F
authors.lastname: Traina
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002465:Cell Movement / Q000235:genetics*; D049109:Cell Proliferation / Q000235:genetics*; D005260:Female; D020868:Gene Silencing; D057809:HEK293 Cells; D006801:Humans; D019169:Jurkat Cells; D007938:Leukemia / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D008969:Molecular Sequence Data; D016601:RNA-Binding Proteins / Q000235:genetics*; D050777:Stathmin / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020298:U937 Cells
chemical_list: C504171:ANKHD1 protein, human; D016601:RNA-Binding Proteins; C493995:STMN1 protein, human; D050777:Stathmin
keywords: ANKHD1; Acute leukemia; Cell proliferation; SIVA1; Stathmin 1