ハイパープラジアからネオプラジアへの移行中の血管新生の誘導
Nature
|May 4, 1989
まとめ
腫瘍の成長は血管新生に依存しています. この研究では,血管新生活性が腫瘍形成前に高可塑性島に現れることが判明し,血管新生が早期がん発生の鍵であることを示唆しています.
科学分野:
- 腫瘍学 腫瘍学
- 発達生物学 発達生物学とは
- がん研究 がん研究
背景:
- 腫瘍の成長は,血管新生,つまり新しい血管の形成に依存しています.
- 腫瘍発達の初期に血管新生状態への移行の正確なタイミングとメカニズムは不明である.
- トランスジェニックマウスモデルは,早期の腫瘍発育を含む多段階の腫瘍発生を研究するためのプラットフォームを提供します.
研究 の 目的:
- 腫瘍発達の初期段階において,いつ,どのように血管新生活性が生じるかを調査する.
- 血管新生に先行するか,またはそれを必要とする正常細胞の増加である高血症かどうかを判断する.
- 血管新生活動の発生と,その後の腫瘍発生を相関させるため.
主な方法:
- 臓のβ細胞で腫瘍遺伝子を発現するトランス遺伝子マウスを利用して,正常状態から腫瘍形成をモデル化しました.
- ハイパープラスティック・アイレットの血管新生活性が観察された in vivo.
- ハイパープラスティック・アイレットの血管新生の可能性を in vivo 条件とは無関係に評価するために,新しい in vitro 測定法を使用した.
主要な成果:
- 血管新生活性が最初に検出されたのは,明らかに腫瘍が形成される前に,ハイパープラスティックな小島の一部分である.
- In vitroアッセイでは,ハイパープラジアだけでは血管新生を誘導しないことが確認されました.
- 血管新生活動の出現は,in vitroでは,in vivoの新血管化と,その後の腫瘍発生率と相関していた.
結論:
- 血管新生の誘導は,早期発がんの重要な出来事です.
- 血管新生はハイパープラジアの必然的な結果ではなく,むしろハイパープラジアの病変のサブセットで発生する特定のイベントです.
- 発見は,腫瘍発達の多段階のプロセスについての洞察を提供し,血管新生を重要な移行点として特定します.
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