胃と腸40巻1号

2005年01月発行

今月の主題 胃癌の時代的変遷と将来展望 主題研究

Helicobacter pyloriと胃癌

著者： 東健¹

所属機関： ¹福井大学医学部第2内科

ページ範囲：P.105 - P.111

要旨　H.pyloriが胃粘膜上皮細胞に接着すると，4型分泌機構がH.pyloriの細胞膜から上皮細胞膜へ針をさすように突き刺さり，その内腔を通して病原因子CagAがH.pyloriから胃粘膜上皮細胞内へと注入される．上皮細胞内に注入されたCagAは上皮内でチロシンリン酸化を受け，チロシンリン酸化されたCagAが，細胞の増殖や分化に重要な役割を担う脱リン酸化酵素Srchomology phosphatase-2（SHP-2）と結合することが認められた．また，CagAには分子多型が存在し，東アジア型CagAを有するH.pylori感染はSHP-2との強い結合を示し，胃粘膜萎縮および胃発癌に関与することが考えられた．

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