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(hào)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(gè)階段都具有動(dòng)態(tài)且常常促進(jìn)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(dú)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(jī)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(jī)制和相互作用。綠色箭頭表示免疫系統(tǒng)的抗腫瘤活動(dòng)，紅色箭頭表示抑制免疫系統(tǒng)的抗腫瘤活動(dòng)。當(dāng)然，腫瘤本身具有強(qiáng)烈的促進(jìn)腫瘤生長(zhǎng)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(xiàn)：
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[2] NCI Dictionary of Cancer Terms. National Cancer Institute. 2011-02-02.
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[4] Spill F, Reynolds DS, Kamm RD, Zaman MH. Impact of the physical microenvironment on tumor progression and metastasis [J]. Current Opinion in Biotechnology. 2016, 40: 41–48.
[5] Frances R. Balkwill, Melania Capasso and Thorsten Hagemann. The tumor microenvironment at a glance [J]. Journal of Cell Science. 2012, 125, 5591–5596.
[6] Hanahan, D. and Coussens, L. M. Accessories to the crime: functions of cells recruited to the tumor microenvironment [J]. Cancer Cell. 2012, 21, 309-322.
[7] Arneth B. Tumor Microenvironment [J]. Medicina (Kaunas). 2019, 56 (1): 15.
