シクロスポリンは,細胞自律的なメカニズムによってがんの進行を誘発する
M Hojo1, T Morimoto, M Maluccio
1Department of Transplantation Medicine and Extracorporeal Therapy, Weill Medical College of Cornell University, New York, New York 10021, USA.
Nature
|February 24, 1999
まとめ
免疫抑制剤であるサイクロスポリンは,宿主免疫から独立した細胞自律的メカニズムを通じて,がん細胞の侵入性を直接増加させます. このプロセスは,成長因子β (TGFβ) の変容を伴うもので,移植後の悪性腫瘍の増加に寄与する.
科学分野:
- 腫瘍学 腫瘍学
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
背景:
- 臓器移植後の悪性病は重大なリスクであり,しばしば宿主の免疫力を低下させる免疫抑制療法と関連しています.
- 免疫抑制薬ががんの進行を促す正確なメカニズムについては,さらなる解明が必要である.
研究 の 目的:
- 免疫抑制薬が悪性腫瘍を強める潜在的な宿主免疫独立メカニズムを調査する.
- 癌の進行を促進する細胞変化を誘発するサイクロスポリンの役割を調査する.
主な方法:
- アデノカルシノーマ細胞をサイクロスポリン (サイクロスポリンA) で治療し,フェノタイプの変化 (形態学,運動性,アンカレージ独立成長) の分析.
- 変形成長因子β (TGFβ) に対するモノクローナル抗体のサイクロスポリン誘発変化に対する効果の評価.
- 免疫不全のSCID-ベージュマウスを用いて,サイクロスポリン治療後の腫瘍の成長と転移を評価するために,抗-TGF-β抗体とまたはそれなしで,体内の研究.
主要な成果:
- サイクロスポリンは,アデノカルシノーマ細胞における重要な形態学的変化,運動性の増加,およびアンカレージ・インディペンデント・成長を引き起こし,侵入性の強化を示唆した.
- これらのサイクロスポリン誘発の変化は,抗TGF-βモノクローナル抗体によって取り消された.
- In vivoでは,サイクロスポリンは免疫不全マウスの腫瘍の成長と転移を促進し,これは抗TGF-β抗体によって防止された.
結論:
- サイクロスポリンは,宿主の免疫抑制から独立して,細胞自律的なメカニズムを通じてがんの進行を促進します.
- サイクロスポリン誘発の変形成長因子β (TGFβ) 産生は,この悪性前効果を媒介する上で重要な役割を果たします.
- これらの発見は,免疫抑制薬に関連する癌リスクを軽減するために,TGF-βを標的とした新しい治療戦略を示唆しています.
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