腫瘍の成長は,まれながん幹細胞によって引き起こされる必要はありません
Priscilla N Kelly1, Aleksandar Dakic, Jerry M Adams
1Walter and Eliza Hall Institute of Medical Research, Melbourne 3050, Australia.
まとめ
がん幹細胞の仮説は,新しい発見によって挑戦されています. ネズミの腫瘍細胞はネズミで容易に成長し,ヒト細胞は癌の幹細胞の欠如ではなく,外来環境で闘うことを示唆しています.
科学分野:
- 腫瘍学 腫瘍学
- がん生物学 がん生物学
- 免疫学 免疫学とは
背景:
- 癌幹細胞仮説は,希少な腫瘍細胞が癌の成長を促すことを示唆している.
- 免疫不全のマウスにおける異種移植は,重要な証拠である.
- これらの研究では,ヒト白血病細胞がしばしば使用されます.
研究 の 目的:
- シンジェニック移植モデルにおける腫瘍発芽細胞の頻度を調査する.
- 異種移植と同種移植を比較することによって,がん幹細胞仮説を再評価する.
- 異種移植における低腫瘍発起細胞周波数の潜在的な理由を探求する.
主な方法:
- ネズミのリンパ腫と白血病の移植を,組織適合性のあるネズミに.
- 腫瘍の成長と,腫瘍を育てる細胞の発生頻度の評価.
- 既存の異種移植データと結果の比較.
主要な成果:
- マウスの腫瘍細胞の高頻度 (少なくとも10分の1以上) は,シンゲニクマウスの腫瘍の成長を誘発した.
- これは,異種移植の研究でしばしば報告されるより低い頻度と対照的です.
- ネズミの腫瘍細胞は,互換性のある宿主の中で成長を開始する能力がより高いことを示唆しています.
結論:
- シンジェニックモデルにおける腫瘍発芽細胞の高頻度は,がん幹細胞仮説が暗示する希少性に異議を唱えている.
- 異種移植の制限により,がん幹細胞の観測頻度が人工的に低下する可能性があります.
- 癌の進行における宿主腫瘍相互作用を理解するためにさらなる研究が必要である.
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