p53の状態とがん治療の有効性 in vivo
S W Lowe1, S Bodis, A McClatchey
1Center for Cancer Research, Massachusetts Institute of Technology, Cambridge 02139.
Science (New York, N.Y.)
|November 4, 1994
まとめ
腫瘍抑制遺伝子p53は,がん治療への反応において極めて重要です. p53が欠けている腫瘍は,放射線治療やアドリアマイシンなどの治療に抵抗性があり,p53を強調しています.
科学分野:
- 腫瘍学 腫瘍学
- 分子生物学は分子生物学である.
- がん遺伝学 がん遺伝学
背景:
- 腫瘍抑制遺伝子p53は,DNA損傷に対する細胞の反応において重要な役割を果たします.
- 治療抵抗性におけるp53の役割を理解することは,効果的ながん治療の開発に不可欠です.
研究 の 目的:
- 遺伝子毒性療法に対する腫瘍の反応に対するp53遺伝子状態の影響を調査する.
- p53欠乏が既得抵抗性および再発につながるかどうかを判断する.
主な方法:
- 遺伝的に定義されたマウス腫瘍モデルにおける治療反応の比較 (p53-発現対p53-欠乏).
- ガンマ放射線とアドリアマイシンによる治療.
- アポプトーシスと腫瘍の成長の評価.
- 獲得したp53変異の分析.
主要な成果:
- p53発現性腫瘍は,治療後に高いアポトーシスと回帰を示した.
- p53欠乏性腫瘍は,抵抗性,継続的な拡大,および低いアポトーシスを示した.
- 既得のp53変異は,当初p53を発現した腫瘍の治療抵抗性と再発と相関しています.
結論:
- p53遺伝子の不活性化により,アポトーシスの欠陥が生じ,治療に抵抗する腫瘍が生じる.
- p53の状態は,放射線治療とアドリアマイシン治療に対する腫瘍の反応の重要な決定因子です.
- p53経路をターゲットにすることで,治療抵抗を克服することができます.
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