メチルトランスフェラーゼの募集と,腫瘍性転写因子による標的プロモーターのDNA超メチル化
Luciano Di Croce1, Veronica A Raker, Massimo Corsaro
1Department of Experimental Oncology, European Institute of Oncology, Milan, Italy. ldicroce@lar.ieo.it
Science (New York, N.Y.)
|February 9, 2002
まとめ
PML-RAR融合タンパク質は,DNAハイパーメチル化を介して遺伝子サイレンスを引き起こし,白血病を誘発します. レチノ酸はこれを逆転させ,がんの発症における表遺伝的変化を強調する.
科学分野:
- 分子生物学は分子生物学である.
- がん研究 がん研究
- エピジェネティクス エピジェネティクス
背景:
- DNAメチレーションは,がんにおける腫瘍抑制遺伝子を静止させるための重要なメカニズムです.
- DNAメチル化特異性を決定する正確な分子機構は,ほとんど不明のままである.
- 異常なDNAメチル化パターンは,悪性変異の特徴である.
研究 の 目的:
- PML-RAR融合タンパク質が遺伝子ハイパーメチル化および静止を誘発する分子メカニズムを解明する.
- PML-RAR媒介のハイパーメチル化が白血病発生における役割を調査する.
- DNA脱メチル化をターゲットにすることで,変異した現象型を逆転させることができるかどうかを判断する.
主な方法:
- PML-RAR融合タンパク質による遺伝子プロモーターを標的とするDNAメチルトランスファーゼ (DNMTs) の徴募を調査した.
- PML-RAR誘発のハイパーメチル化が遺伝子発現と細胞変異に与える影響を評価した.
- プロモーターの脱メチル化を誘発し,現象型逆転を観察するためにレチノ酸治療を使用しました.
主要な成果:
- PML-RAR融合タンパク質は,DNAメチルトランスフェラーゼを特定の遺伝子プロモーターに積極的に勧誘し,遺伝子ハイパーメチル化と転写サイレンシングにつながります.
- このPML-RAR誘発の超メチル化が,タンパク質の白血病発生の可能性に有意に寄与することが判明した.
- レチノ酸による治療は,プロモーターの脱メチル化,遺伝子発現の回復,変異した細胞現象型の逆転をもたらした.
結論:
- 癌の発症における遺伝的変異 (PML-RAR融合) と表遺伝的変化 (DNA超メチル化) の間の直接的なメカニズム的関連が確立された.
- PML-RARによって誘発されるDNAハイパーメチル化が,発がんの初期段階における重要な要因であることを実証した.
- レチノ酸は,腫瘍原性の表遺伝的改変を逆転させる可能性のある治療薬として示されました.
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