テロメア縮小はヒトの結腸直腸がんおよび老化とともに起こる

N D Hastie¹, M Dempster, M G Dunlop

¹MRC Human Genetics Unit, Western General Hospital, Edinburgh, UK.

Nature

|August 30, 1990

まとめ

テロメアの縮小,保護的なDNAキャップの喪失は,ほとんどの大腸がんで観察されています. このテロメア縮小は,腫瘍発達の過程における遺伝的不安定化に寄与する可能性がある.

科学分野:

遺伝学遺伝学とは
腫瘍学腫瘍学
分子生物学は分子生物学である.

背景:

エンドツーエンドの染色体融合は腫瘍で観察され,潜在的に遺伝的不安定性を引き起こします.
これらの融合は,染色体末端 (テロメア) にあるG豊富な重複の喪失から生じる可能性があります.

研究の目的:

一般的な腫瘍におけるテロメア喪失または縮小を調査するために.
テロメアの長さ,老化,および正常な組織とがん組織における細胞分裂の関係を調査する.

主な方法:

結腸直腸がんにおけるテロメアの繰り返し配列の長さの分析.
同じ患者の腫瘍組織と正常な結腸内粘膜のテロメア長さの比較.
異なる組織 (結腸内粘膜,血液,胎児組織,精子) および年齢層におけるテロメア長さの変動の評価.

主要な成果:

ほとんどの分析された結腸直腸がんは,正常な組織と比較して,テロメアの繰り返し配列の長さが短縮されていることを示しています.
テロメア配列は,胎児の組織と精子よりも,大人の結腸内粘膜と血液において著しく小さい.
平均テロメアの長さは,血液と結腸内粘膜の両方で,年齢とともに減少します.

結論:

テロメア喪失は結腸直腸がんの一般的な特徴であり,腫瘍発生に潜在的に寄与する可能性があります.
テロメアの長さは,組織と腫瘍形成における細胞分裂史の指標として機能する.
テロメラーゼは,ほとんどの体組織で不活性である可能性があり,時間の経過とともにテロメアの漸進的な縮小につながる.

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