title: Asparagine synthetase is partially localized to the plasma membrane and upregulated by L-asparaginase in U937 cells.
abstract: This study investigated the intracellular localization of asparagine synthetase (ASNS) in the relation with chemoresistance in leukemia. pIRES-GFP-ASNS-Flag/Neo expression vector was transiently tansfected into SK-N-MC cells and 297T cells respectively. Immunofluorescence and Western blot analysis were performed for cellular localization of ASNS respectively. U937 cells were treated with L-asparaginase for 48 h and examined for endogenous ASNS expression on plasma membrane by immunofluorescence staining. Immunofluorescence staining showed that the transiently expressed ASNS was partly localized on transfected-SK-N-MC cell surface. Moreover, Western blotting exhibited that ASNS expressed both in cytosol and on plasma membrane of transfected-293T cells. Immunofluorescence staining with anti-ASNS-specific monoclonal antibody revealed that endogenous ASNS was localized on the plasma membrane of U937 cells, except for its distribution in the cytosol. In addition, ASNS exhibited a higher expression on plasma membrane after treatment with L-asparaginase as compared with the untreated cells. It was concluded that the subcellular translocation of ASNS may play an important role in L-asparaginase resistance in leukemia cells.
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Yingyi
authors.initials: Y
authors.lastname: He
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Benshang
authors.initials: B
authors.lastname: Li
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Changying
authors.initials: C
authors.lastname: Luo
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Shuhong
authors.initials: S
authors.lastname: Shen
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Huiliang
authors.initials: H
authors.lastname: Xue
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China.
authors.forename: Jingyan
authors.initials: J
authors.lastname: Tang
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, 200127, China. ljgscmc@yahoo.com.cn.
authors.forename: Longjun
authors.initials: L
authors.lastname: Gu
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001215:Asparaginase / Q000494:pharmacology*; D001217:Aspartate-Ammonia Ligase / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans; D014162:Transfection; D020298:U937 Cells
chemical_list: D000970:Antineoplastic Agents; D001215:Asparaginase; D001217:Aspartate-Ammonia Ligase