FHL2 interacts with CALM and is highly expressed in acute erythroid leukemia

The t(10;11)(p13;q14) translocation results in the fusion of the CALM (clathrin assembly lymphoid myeloid leukemia protein) and AF10 genes. This translocation is observed in acute myeloblastic leukemia (AML M6), acute lymphoblastic leukemia (ALL) and malignant lymphoma. Using a yeast two-hybrid screen, the four and a half LIM domain protein 2 (FHL2) was identified as a CALM interacting protein. Recently, high expression of FHL2 in breast, gastric, colon, lung as well as in prostate cancer was shown to be associated with an adverse prognosis. The interaction between CALM and FHL2 was confirmed by glutathione S-transferase-pulldown assay and co-immunoprecipitation experiments. The FHL2 interaction domain of CALM was mapped to amino acids 294–335 of CALM. The transcriptional activation capacity of FHL2 was reduced by CALM, but not by CALM/AF10, which suggests that regulation of FHL2 by CALM might be disturbed in CALM/AF10-positive leukemia. Extremely high expression of FHL2 was seen in acute erythroid leukemia (AML M6). FHL2 was also highly expressed in chronic myeloid leukemia and in AML with complex aberrant karyotype. These results suggest that FHL2 may play an important role in leukemogenesis, especially in the case of AML M6

PTK2 and PTPN11 expression in myelodysplastic syndromes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)OBJECTIVE: The aim of this study was to evaluate the expression of protein tyrosine kinase 2 and protein tyrosine phosphatase non-receptor type 11, which respectively encode focal adhesion kinase protein and src homology 2 domain-containing protein-tyrosine phosphatase 2, in hematopoietic cells from patients with myelodysplastic syndromes. METHODS: Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions were analyzed by quantitative polymerase chain reaction in bone marrow cells from patients with myelodysplastic syndromes and healthy donors. RESULTS: Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions did not significantly differ between normal cells and myelodysplastic cells. CONCLUSIONS: Our data suggest that despite the relevance of focal adhesion kinase and src homology 2 domaincontaining protein-tyrosine phosphatase 2 in hematopoietic disorders, their mRNA expression do not significantly differ between total bone marrow cells from patients with myelodysplastic syndromes and healthy donors.681013711375Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

The CATS (FAM64A) protein is a substrate of the Kinase Interacting Stathmin (KIS)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The CATS protein (also known as FAM64A and RCS1) was first identified as a novel CALM (PICALM) interactor that influences the subcellular localization of the leukemogenic fusion protein CALM/AF10. CATS is highly expressed in cancer cell lines in a cell cycle dependent manner and is induced by mitogens. CATS is considered a marker for proliferation, known to control the metaphase-to-anaphase transition during the cell division. Using CATS as a bait in a yeast two-hybrid screen we identified the Kinase Interacting Stathmin (MS or UHMK1) protein as a CATS interacting partner. The interaction between CATS and KIS was confirmed by GST pull-down, co-immunopreciptation and co-localization experiments. Using kinase assay we showed that CATS is a substrate of KIS and mapped the phosphorylation site to CATS serine 131 (S131). Protein expression analysis revealed that KIS levels changed in a cell cycle-dependent manner and in the opposite direction to CATS levels. In a reporter gene assay KIS was able to enhance the transcriptional repressor activity of CATS, independent of CATS phophorylation at S131. Moreover, we showed that CATS and KIS antagonize the transactivation capacity of CALM/AF10.In summary, our results show that CATS interacts with and is a substrate for KIS, suggesting that KIS regulates CATS function. (c) 2013 Elsevier B.V. All rights reserved.1833512691279Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Deutsche Krebshilfe [109031]Deutsche Forschungsgemeinschaft [SFB 684 A6, BO 938/4-1]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [07/08019-1, 07/54870-5]CNPq [101624/2011-5]Deutsche Krebshilfe [109031]Deutsche Forschungsgemeinschaft [SFB 684 A6, BO 938/4-1

The CALM and CALM/AF10 interactor CATS is a marker for proliferation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The CATS protein was recently identified as a novel CALM interacting protein. CATS increases the nuclear and specifically the nucleolar localization of the leukemogenic CALM/AF10 fusion protein. We cloned and characterized the murine Cats gene. Detailed analysis of murine Cats expression during mouse embryogenesis showed an association with rapidly proliferating tissues. interestingly, the Cats transcript is highly expressed in murine hematopoietic cells transformed by CALM/AF10. The CATS protein is highly expressed in leukemia, lymphoma and tumor cell lines but not in non-proliferating T-cells or human peripheral blood lymphocytes. CATS protein levels are cell cycle dependent and it is induced by mitogens, suggesting a role of CATS in the control of cell proliferation and possibly CALM/AF10-mediated leukemogenesis. (C) 2008 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.24356367Deutsche Jose Carreras Leukamie-Stiftung e.V. (DJCLS) [F02/02, F05/06]Frauenbeauftragte-LMU, Munich, GermanyFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)National Genome Research Network (NGFN) grant from the German Ministry of Education and Research (BMBF) [N1KR-S31T15]Deutsche Forschungsgemeinschaft (DFG) [SFB 684, A6]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Deutsche Jose Carreras Leukamie-Stiftung e.V. (DJCLS) [F02/02, F05/06]FAPESP [07/08019-1, 07/54870-5]National Genome Research Network (NGFN) grant from the German Ministry of Education and Research (BMBF) [N1KR-S31T15]Deutsche Forschungsgemeinschaft (DFG) [SFB 684, A6