Dr. Saharuddin Bin Mohamad

Dr. Saharuddin Bin Mohamad is currently working in bioinformatics in University of Malaya, Malaysia. He is using bioinformatics techniques to study GcMAF to further understand its effectiveness in cancer therapy. He worked under Professor Hitoshi Hori of Tokushima University, Japan.

Here is a listing of some of Dr. Mohamad's work related to Gc-MAF.

Preparation of Gc protein-derived macrophage activating factor (GcMAF) and its structural characterization and biological activities

SAHARUDDIN BIN MOHAMAD (1) ; NAGASAWA Hideko (1) ; UTO Yoshihiro (1) ; HORI Hitoshi (1)
(1) Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima, Minamijyosanjimacho-2, Tokushima, 770-8506, JAPAN
Anticancer research ISSN 0250-7005 Annual Meeting of the Society of Biotherapeutic Approaches No5, Fukuoka , JAPON (08/12/2001) 2002, vol. 22, no6C, pp. 4297-4300 [4 page(s) (article)] (21 ref.)

Abstract
Background: Gc protein has been reported to be a precursor of Gc protein-derived macrophage activation factor (GcMAF) in the inflammation- primed macrophage activation cascade. An inducible beta-galactosidase of B cells and neuraminidase of T cells convert Gc protein to GcMAF.
Materials and Methods: Gc protein from human serum was purred using 25(OH)D3affinity column chromatography and modified to GcMAF using immobilized glycosidases (beta-galactosidase and neuraminidase) The sugar moiety structure of GcMAF was characterized by lectin blotting by Helix pomatia agglutinin. The biological activities of GcMAF were evaluated by a superoxide generation assay and a phagocytosis assay.
Results: We successfully purified Gc protein from human serum. GcMAF was detected by lectin blotting and showed a high biological activity.
Conclusion: Our results support the importance of the terminal N-acetylgalactosamine moiety in the GeMAF-mediated macrophage activation cascade, and the existence of constitutive GcMAF in human serum. These preliminary data are important for designing small molecular GcMAF mimics.

Gc protein-derived macrophage activating factor (GcMAF): isoelectric focusing pattern and tumoricidal activity.

Anticancer Res. ;23 (6a):4451-7 14666733 (P,S,E,B)
Saharuddin Bin Mohamad, Hideko Nagasawa, Hideyuki Sasaki, Yoshihiro Uto, Yoshinori Nakagawa, Ken Kawashima, Hitoshi Hori Department of Biological Science and Technology, Faculty of Engineering, University of Tokushima, Minamijyosajimacho-2, Tokushima, 770-8506 Japan.
BACKGROUND: Gc protein is the precursor for Gc protein-derived macrophage activating factor (GcMAF), with three phenotypes: Gc1f, Gc1s and Gc2, based on its electrophoretic mobility. The difference in electrophoretic mobility is because of the difference in its posttranslational sugar moiety composition.
MATERIALS AND METHODS: We compared the difference between Gc protein and GcMAF electrophoretic mobility using the isoelectric focusing (IEF) method. The tumoricidal activity of GcMAF-treated macrophage was evaluated after coculture with L-929 cell. The tumoricidal mechanism was investigated using TNF bioassay and nitric oxide (NO) release.
RESULTS: The difference in Gc protein and GcMAF electrophoretic mobility was detected. The tumoricidal activity of GcMAF-treated macrophage was detected, but no release of TNF and NO was detected.
CONCLUSION: The difference of isoelectric focusing mobility in Gc protein and GcMAF would be useful to develop a GcMAF detection method. GcMAF increased macrophage tumoricidal activity but TNF and NO release were not involved in the mechanism.

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

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.

Characterization of human Gc protein-derived macrophage activation factor (GcMAF) and its functional role in macrophage tumoricidal activity.

Saharuddin B Mohamad, Hitoshi Hori, Hideko Nagasawa, Kenji Usui, Yoshihiro Uto Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima, Tokushima, 770-8506, Japan. Adv Exp Med Biol. 2003 ;510 :77-82 12580408 (P,S,E,B)

No abstract available.

Photos of Dr. Saharuddin Bin Mohammad

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