人間のアリル炭化水素受容体の内生性腫瘍促進リガンドである
Christiane A Opitz1, Ulrike M Litzenburger, Felix Sahm
1Department of Neurooncology, Neurology Clinic and National Center for Tumor Diseases, University Hospital of Heidelberg, 69120 Heidelberg, Germany.
Nature
|October 7, 2011
まとめ
研究者らは,トリプトファン (Trp) の代謝産物であるキヌレニン (Kyn) を,アリル炭水化物受容体 (AHR) の内生リガンドとして特定した. このTDO-AHR経路は,腫瘍の成長と免疫抑制を促進し,がんの進行に影響を与えます.
科学分野:
- 免疫学 免疫学とは
- がん生物学 がん生物学
- 分子生物学は分子生物学である.
背景:
- アリル炭化水素受容体 (AHR) は環境毒素によって活性化され,細胞プロセスに関与します.
- 生理学的条件下でのAHRの内生性リガンドは未確認のままである.
研究 の 目的:
- 人間のAHRのための内生リンガンドを特定する.
- TDO-AHR経路ががん生物学と免疫反応における役割を調査する.
主な方法:
- 基ヌルニン (Kyn) を内源的なAHRリガンドとして識別する.
- 腫瘍細胞におけるトリプトファン-2,3-二酸化原酵素 (TDO) の活性に関する分析.
- 腫瘍の免疫抑制,生存,および運動性におけるTDO-AHR経路の役割の評価.
- TDO-AHR経路の活性とヒトの脳腫瘍の進行および生存の相関.
主要な成果:
- トリプトファン (Trp) カタボライトであるキヌレニン (Kyn) は,ヒトAHRの新種の内生リガンドとして特定されています.
- 人間の腫瘍細胞は,トリプトファン-2,3-二酸化原酶 (TDO) を通してKynを構成的に生成する.
- TDO由来のKynは,抗腫瘍免疫反応を抑制し,AHR経由で腫瘍細胞の生存と運動性を促進する.
- TDO-AHR経路はヒトの脳腫瘍に活性化しており,悪性腫瘍の進行と生存率の低下と相関しています.
結論:
- キヌレニン (Kyn) は,AHRを活性化する,以前未知の内生リンガンドである.
- TDO-AHR経路は,免疫抑制と腫瘍進行のための新しいメカニズムを表しています.
- この経路は,がんと免疫生物学に重大な影響を及ぼし,潜在的な治療目標を提供します.
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