正常な結腸内皮細胞における体性変異の風景

Henry Lee-Six¹, Sigurgeir Olafsson¹, Peter Ellis¹

¹Wellcome Sanger Institute, Hinxton, UK.

Nature

|October 25, 2019

まとめ

早期の結腸直腸腫瘍の変化は,形態学的に正常な組織で起こります. 全ゲノム配列解析により,正常な結腸内密室の1%に誘導因子の突然変異がみられ, がんが広範囲に広がった変化から発症することを示した.

科学分野:

ゲノミクス
癌生物学
分子病理学

背景:

結腸腺腫と結腸癌の配列は,癌の発症の既知のモデルである.
形態学的に正常な結腸内組織における早期の腫瘍的変化は十分に理解されていません.
ほとんどの癌は初期段階の理解が限られています

研究の目的:

腸直腸腫瘍の発達における初期の遺伝的変化を調査する.
形態学的に正常な大腸内密室の体内の遺伝子変異を分析する.
大腸内皮質における初期ドライバー変異の流行と性質を理解する.

主な方法:

全ゲノム配列解析で 42人の正常な結腸細胞を調べました
変異シグネチャーと正常な結腸組織におけるドライバー変異の分析
大腸内皮質におけるゲノムとクローン進化の定量評価.

主要な成果:

どこにでも存在し,継続的な,そして中断的な変異過程のサインを特定した.
中年の正常な結腸内密室の約1%で誘導因子変異が発見されました
結腸直腸がんは正常な細胞よりも顕著に高い変異負荷を持つことが示された.

結論:

結腸腺腫と結腸癌は,形態学的に正常な上皮に広がる腫瘍性プロセスから生じる.
初期段階の遺伝的変異は正常な結腸内密室で一般的です
正常な結腸細胞の配列は癌のゲノムとクローン進化に関する重要な定量的な洞察を提供します

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