title: Helicobacter pylori, a carcinogen, induces the expression of melanoma antigen-encoding gene (Mage)-A3, a cancer/testis antigen.
abstract: Cancer/testis antigens (CTAs) are known to be expressed in various cancer types but are minimally or not expressed in normal tissues except for germline tissues. CTAs are attractive targets for cancer immunotherapy and diagnosis because of their restricted expression. The mechanisms of CTAs expression are unclear because the inducers of CTAs expression remain to be elucidated. We hypothesized that carcinogens may induce the cellular expression of CTAs. To prove this, we attempted to inoculate Helicobacter pylori, a known carcinogen, in Meth-A cells, normal gastric cells, and normal splenocytes and induce the expression of a CTA. Melanoma antigen-encoding gene (Mage)-A3, one of the CTAs, was not expressed in both normal cells but in Meth-A cells inoculated with H. pylori. Furthermore, we performed limiting dilution using Meth-A cells inoculated with H. pylori and established derivative clone from Meth-A designated as Meth-A/pylori/3C3 which permanently express Mage-A3 after excluding H. pylori. We herein report the first successful induction of a CTA in a cell line via exposure to a carcinogenic agent. Furthermore, the establishment of Meth-A/pylori/3C3, which is Meth-A expressing Mage-A3, is considered to contribute to the resolution of the mechanism of CTAs expression.
authors: Division of Biomedical Research, Kitasato Institute Medical Center Hospital, Kitasato University, Arai 6-100, Kitamoto 364-8501, Japan. fukuyam@insti.kitasato-u.ac.jp
authors: Takashi
authors: T
authors: Fukuyama
authors: Taiga
authors: T
authors: Yamazaki
authors: Tomoko
authors: T
authors: Fujita
authors: Takayuki
authors: T
authors: Uematsu
authors: Yoshinobu
authors: Y
authors: Ichiki
authors: Hiroshi
authors: H
authors: Kaneko
authors: Tatsuo
authors: T
authors: Suzuki
authors: Noritada
authors: N
authors: Kobayashi
mesh_terms: D000818:Animals; D017209:Apoptosis; D005354:Fibrosarcoma / Q000139:chemically induced; D005434:Flow Cytometry; D005753:Gastric Mucosa / Q000378:metabolism*; D016481:Helicobacter Infections / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D016480:Helicobacter pylori / Q000472:pathogenicity*; D058950:Melanoma-Specific Antigens / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012513:Sarcoma, Experimental / Q000378:metabolism* / Q000473:pathology; D013154:Spleen / Q000378:metabolism* / Q000473:pathology / Q000821:virology; D013270:Stomach / Q000473:pathology / Q000821:virology; D014407:Tumor Cells, Cultured
chemical_list: D058950:Melanoma-Specific Antigens; D012333:RNA, Messenger