トライソミーは,ダウン症候群のマウスモデルにおけるApc (Min) 媒介の腫瘍を抑制する
Thomas E Sussan1, Annan Yang, Fu Li
1Department of Physiology and The Institute for Genetic Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Nature
|January 4, 2008
まとめ
ダウン症候群 (トリソミー21) の個人は,腸内腫瘍の発生率が低い可能性があります. マウスモデルでは,特にEts2遺伝子が関わるトライソミーは,腫瘍の発症を大幅に減少させ,潜在的な予防効果を示唆していることが示されています.
科学分野:
- 遺伝学 遺伝学とは
- がん生物学 がん生物学
- 発達生物学 発達生物学とは
背景:
- ダウン症候群 (トリソミー21) のがん発生率に関する流行病学的研究は,矛盾する結果をもたらします.
- アヌプロイド症における癌リスクの生物学的根拠を理解することは極めて重要です.
研究 の 目的:
- マウスモデルを用いてトライソミーと腸内腫瘍発生率の関係を調査する.
- トライソミがApc(Min) 媒介の腸内腫瘍の発達に影響するかどうかを判断する.
主な方法:
- ダウンス症候群の側面を模倣したアヌプロイドマウスモデル (Ts65Dn,Ts1Rhr,Ms1Rhr) を利用した.
- これらのモデルにおける数値化された Apc ((Min)) 媒介の腸内腫瘍数.
- Ets2を含む特定の遺伝子の役割が,腫瘍発育に対する投与量に敏感な効果を分析した.
主要な成果:
- Ts65DnとTs1Rhrのマウスのヒト染色体21のオートログのトリソミーは,腸内腫瘍の数を大幅に減少させた.
- Ms1Rhrマウスの同じ遺伝子に対するモノソミーは,腫瘍数を増加させた.
- Ets2遺伝子は,腫瘍発症率に対する投与量に敏感な効果の主な寄与者として特定されました.
結論:
- トライソミーは,特にEts2が関わっているので,腸内腫瘍の発症に対する保護効果を与えます.
- Ets2の過剰発現は抑制剤として作用し,従来の腫瘍抑制とは異なる.
- Ets2および関連する遺伝子のアップレギュレーションは, ploidy にかかわらず,癌に対する予防効果を提供することができます.
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