胃と腸55巻6号

2020年05月発行

今月の主題 スキルス胃癌—病態と診断・治療の最前線 主題研究

スキルス胃癌のゲノム解析と病態

著者： 石川俊平¹

所属機関： ¹東京大学大学院医学系研究科衛生学分野

ページ範囲：P.835 - P.843

要旨●近年のがんゲノムシーケンスによって，スキルス胃癌の胃癌全体における相対的な位置付けが，がんゲノムの面からも明らかになってきた．2014年にびまん型（diffuse-type）胃癌に特徴的なRHOAパスウェイのドライバー遺伝子変異が同定され，またSNVやCNVといった体細胞ゲノム変異に乏しいGS（genomically stable）サブタイプがびまん型胃癌と大きくオーバーラップすることが明らかになった．スキルス胃癌は歴史的に若年性のBorrmann 4型胃癌を指すこともあるが，ゲノム解析の観点からは，より広義のびまん型胃癌と比較してドライバー遺伝子変異の頻度に一定の違いはあるが両者に質的な違いはなく，連続的な疾患カテゴリと考えられる．また，多数のびまん型胃癌のがんゲノムシーケンスによって，日本人集団に予想以上の頻度で発症素因となるCDH1の胚細胞変異が存在することが明らかとなった．

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