My NCBI | Sign In
RSS Settings
  • Search:

Display Settings:

Format

Send to:

Choose Destination

    Comp Biochem Physiol A Mol Integr Physiol. 2002 May;132(1):1-8.

    Tumor cell alpha-N-acetylgalactosaminidase activity and its involvement in GcMAF-related macrophage activation.

    Mohamad SB, Nagasawa H, Uto Y, Hori H.

    Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima, Tokushima 770-8506, Japan.

    Alpha-N-acetyl galactosaminidase (alpha-NaGalase) has been reported to accumulate in serum of cancer patients and be responsible for deglycosylation of Gc protein, which is a precursor of GcMAF-mediated macrophage activation cascade, finally leading to immunosuppression in advanced cancer patients. We studied the biochemical characterization of alpha-NaGalase from several human tumor cell lines. We also examined its effect on the potency of GcMAF to activate mouse peritoneal macrophage to produce superoxide in GcMAF-mediated macrophage activation cascade. The specific activity of alpha-NaGalases from human colon tumor cell line HCT116, human hepatoma cell line HepG2, and normal human liver cells (Chang liver cell line) were evaluated using two types of substrates; GalNAc-alpha-PNP (exo-type substrate) and Gal-beta-GalNAc-alpha-PNP (endo-type substrate). Tumor-derived alpha-NaGalase having higher activity than normal alpha-NaGalase, had higher substrate specificity to the exo-type substrate than to the endo-type substrate, and still maintained its activity at pH 7. GcMAF enhance superoxide production in mouse macrophage, and pre-treatment of GcMAF with tumor cell lysate reduce the activity. We conclude that tumor-derived alpha-NaGalase is different in biochemical characterization compared to normal alpha-NaGalase from normal Chang liver cells. In addition, tumor cell-derived alpha-NaGalase decreases the potency of GcMAF on macrophage activation.

    PMID: 12062184 [PubMed - indexed for MEDLINE]

    Publication Types, MeSH Terms, Substances

    Publication Types:

    MeSH Terms:

    Substances:

    LinkOut - more resources

    Full Text Sources:

    Libraries:

    Supplemental Content

    Click here to read

    Related articles

    All links from this record

    • Related Articles

      Calculated set of PubMed citations closely related to the selected article(s) retrieved using a word weight algorithm. Related articles are displayed in ranked order from most to least relevant, with the “linked from” citation displayed first.

    • Gene

      Gene records that cite the current articles. Citations in Gene are added manually by NCBI or imported from outside public resources.

    • Gene (GeneRIF)

      Gene records that have the current articles as Reference into Function citations (GeneRIFs). NLM staff reviewing the literature while indexing MEDLINE add GeneRIFs manually.

    • HomoloGene

      HomoloGene clusters of homologous genes and sequences that cite the current articles. These are references on the Gene and sequence records in the HomoloGene entry.

    • Nucleotide (RefSeq)

      NCBI nucleotide Reference Sequences (RefSeqs) that are cited in the current articles, included in the corresponding Gene Reference into Function, or that include the PubMed articles as references.

    • Nucleotide (Weighted)

      Nucleotide records associated with the current articles through the Gene database. These are the related sequences on the Gene record that are added manually by NCBI.

    • Protein (RefSeq)

      NCBI protein Reference Sequences (RefSeqs) that are cited in the current articles, included in the corresponding Gene Reference into Function, or that include the PubMed articles as references.

    • Protein (Weighted)

      Protein records associated with the current articles through related Gene database records. These are the related sequences on the Gene record that are added manually by NCBI.

    • Substance (MeSH Keyword)

      PubChem chemical substance (submitted) records that are classified under the same Medical Subject Headings (MeSH) controlled vocabulary as the current articles.

    • Taxonomy via GenBank

      Taxonomy records associated with the current articles through taxonomic information on related molecular database records (Nucleotide, Protein, Gene, SNP, Structure).

    • UniGene

      UniGene clusters of expressed sequences that are associated with the current articles through references on the clustered sequence records and related Gene records.

    • GEO Profiles

      Gene Expression Omnibus (GEO) Profiles of molecular abundance data. The current articles are references on the Gene record associated with the GEO profile.

    Recent activity