title: c-myc gene mutation in gastric mucosa-associated lymphoid tissue (MALT) lymphoma and diffuse large B-cell lymphoma.
abstract: The c-myc gene is involved in important cellular processes, including cell proliferation, differentiation, and apoptosis. We analyzed mutation of the c-myc gene in 51 patients with gastric lymphoma [27 patients with low-grade mucosa-associated lymphoid tissue (MALT) lymphoma, 11 with high-grade MALT lymphoma, and 13 with diffuse large B-cell lymphoma (DLL)], by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. We also evaluated the relationship between mutation of the c-myc gene and regression of low-grade MALT lymphoma after Helicobacter pylori (H. pylori) eradication. Mutation in exon 2 of the c-myc gene was present in 2 of 20 (10%) patients with low-grade MALT lymphoma, in 1 of 7 (14%) patients with high-grade MALT lymphoma, and none of 10 patients with DLL. The 3 patients who had mutations of the gene, showed different patterns of mobility shift, suggesting different mutations. In addition, 15 patients with low-grade MALT lymphoma received anti-H. pylori therapy. All the patients achieved eradication. Nine of the 15 (60%) patients with low-grade MALT lymphoma showed complete regression (CR), 3 (20%) showed partial regression (PR), and 3 (20%) showed no change (NC). One of the 9 (11%) CR patients had a mutation of the c-myc gene. None of the 3 PR and 3 NC patients had mutation of the gene. There was no significant difference between the frequencies among the c-myc gene mutation in CR, in PR and in NC patients. These data suggest that mutation of the c-myc gene may not be commonly associated with development of gastric MALT lymphoma and DLL, and may not be associated with regression of low-grade MALT lymphoma after H. pylori eradication.
authors.affiliation: First Department of Internal Medicine, Hiroshima University School of Medicine, Minami-ku, Hiroshima 734-8551, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hiyama
authors.forename: K
authors.initials: K
authors.lastname: Haruma
authors.forename: Y
authors.initials: Y
authors.lastname: Kitadai
authors.forename: M
authors.initials: M
authors.lastname: Ito
authors.forename: H
authors.initials: H
authors.lastname: Masuda
authors.forename: M
authors.initials: M
authors.lastname: Miyamoto
authors.forename: S
authors.initials: S
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Yoshihara
authors.forename: K
authors.initials: K
authors.lastname: Sumii
authors.forename: F
authors.initials: F
authors.lastname: Shimamoto
authors.forename: K
authors.initials: K
authors.lastname: Chayama
mesh_terms: D000897:Anti-Ulcer Agents / Q000627:therapeutic use; D017291:Clarithromycin / Q000627:therapeutic use; D018450:Disease Progression; D005091:Exons; D016259:Genes, myc; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori; D006801:Humans; D016393:Lymphoma, B-Cell / Q000235:genetics* / Q000473:pathology; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000382:microbiology / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics* / Q000473:pathology; D009154:Mutation; D009367:Neoplasm Staging; D009853:Omeprazole / Q000627:therapeutic use; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational
chemical_list: D000897:Anti-Ulcer Agents; D017291:Clarithromycin; D009853:Omeprazole