腫瘤微環(huán)境
腫瘤微環(huán)境（TME）是指惡性和非轉(zhuǎn)化細(xì)胞之間的環(huán)境，包括周圍的血管、免疫細(xì)胞、成纖維細(xì)胞、信號分子和細(xì)胞外基質(zhì)（ECM）[1-4]。癌癥不僅僅是惡性細(xì)胞的聚集，而是復(fù)雜的“變態(tài)”器官，許多其他細(xì)胞被招募并可能被轉(zhuǎn)化的細(xì)胞所腐化 [5]。腫瘤微環(huán)境中的非惡性細(xì)胞在癌癥發(fā)生的各個階段都具有動態(tài)且常常促進腫瘤的功能 [6]。
除了惡性細(xì)胞外，腫瘤微環(huán)境中還存在脂肪細(xì)胞、成纖維細(xì)胞、腫瘤血管、淋巴細(xì)胞、樹突狀細(xì)胞和癌相關(guān)成纖維細(xì)胞。每種細(xì)胞類型都具有獨特的免疫能力，決定了腫瘤是否能夠存活并影響周圍的細(xì)胞 [7]。
圖1. 腫瘤微環(huán)境(TME)最重要的機制和相互作用示意圖概述
圖1展示了腫瘤微環(huán)境的最重要機制和相互作用。綠色箭頭表示免疫系統(tǒng)的抗腫瘤活動，紅色箭頭表示抑制免疫系統(tǒng)的抗腫瘤活動。當(dāng)然，腫瘤本身具有強烈的促進腫瘤生長的效應(yīng)（中間的循環(huán)）。
● Angiogenesis Inhibitor in Cancer
● Angiogenic Activator in Cancer
● ECM and ECM Regulators
● MDSC Cytokines and Growth Factors
● MDS Intracellular Signaling Factors
● MDSC Phenotyping-Negative/Positive Markers
參考文獻：
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