晏 軍,曹 殊
(自貢市第一人民醫(yī)院腫瘤科,四川自貢 643000)
近年來研究發(fā)現(xiàn),腫瘤的進(jìn)展不僅是腫瘤細(xì)胞的基因突變及過度生長的獨(dú)立事件,而且是惡性腫瘤細(xì)胞及其周圍的腫瘤基質(zhì)微環(huán)境之間相互協(xié)同作用的結(jié)果。腫瘤微環(huán)境是由腫瘤細(xì)胞、細(xì)胞外基質(zhì)的結(jié)構(gòu)成分及鑲嵌其中的多種相互依賴的基質(zhì)細(xì)胞,包括腫瘤相關(guān)成纖維細(xì)胞(cancer-associated fibroblast,CAFs)、免疫細(xì)胞、內(nèi)皮細(xì)胞、周細(xì)胞及骨髓來源細(xì)胞等及其分泌的溶解因子組成,區(qū)別于正常細(xì)胞與其周圍組織形成的微環(huán)境[1-2]。腫瘤相關(guān)成纖維細(xì)胞是腫瘤基質(zhì)的主要組成部分,在腫瘤的發(fā)生、增殖、侵襲及轉(zhuǎn)移多個環(huán)節(jié)中發(fā)揮著重要作用[3]。
成纖維細(xì)胞與細(xì)胞外基質(zhì)的合成、沉積及傷口的愈合密切相關(guān)。在正常情況下,成纖維細(xì)胞處于靜止?fàn)顟B(tài),在傷口愈合和纖維化過程中被激活稱為肌成纖維細(xì)胞(Myofibroblasts),最早于1971年被Giulin在傷口愈合過程中發(fā)現(xiàn)[4]?!澳[瘤就像是永不愈合的傷口”[5],在腫瘤微環(huán)境中,被激活的成纖維細(xì)胞不會像其在傷口愈合后發(fā)生凋亡,而是處于持續(xù)激活狀態(tài),成為腫瘤發(fā)生、生長的重要原因,故稱作CAFs。CAFs于1999年,由Oliumi等首先從前列腺癌組織中分離獲得[6]。
CAFs形態(tài)相似、功能多樣又具有較大的異質(zhì)性。主要表現(xiàn)為細(xì)胞體積較大,排列方式雜亂,呈梭形、紡錘形,細(xì)胞核呈鋸齒狀,細(xì)胞漿中有各種收縮細(xì)絲或張力纖維絲、豐富的粗面內(nèi)質(zhì)網(wǎng)、細(xì)胞間連接和發(fā)育成熟的纖維粘連素。胞核著色均勻,核仁明顯。另見散在的電子致密斑,類似平滑肌的致密斑。由于CAFs與Myofibroblasts存在許多的相似性,其中包括兩者最廣泛應(yīng)用的生物學(xué)標(biāo)志均是α-SMA,但是僅憑 α-SMA表達(dá)并不能代表所有的CAFs[7-8],其次成纖維特異蛋白 1(Fibroblast specific protein 1,F(xiàn)SP1)、成纖維激活蛋白(Fibroblast activation protein,F(xiàn)AP)及血小板衍生因子(Platelet-derived growth factor,PDGF)受體 α/β 也是 CAFs重要生物學(xué)標(biāo)志[9]。其中FSP1調(diào)控細(xì)胞周期及細(xì)胞骨架的完整性,其異常表達(dá)能促進(jìn)腫瘤的生長及轉(zhuǎn)移[10];FAP、PDGF受體 α/β 在90%的腫瘤組織的CAFs中都有表達(dá)[11-12]。
到目前為止,CAFs的概念界定仍然比較模糊,原因可能是CAFs的異質(zhì)性。在腫瘤微環(huán)境中的CAFs的來源會因腫瘤的類型和腫瘤的不同區(qū)域而發(fā)生變化[13]。并且其來源的機(jī)制尚未完全闡釋清楚??偟膩碚f,活化的成纖維細(xì)胞主要來源于間質(zhì)的成纖維細(xì)胞、血管的內(nèi)皮細(xì)胞和外皮細(xì)胞、骨髓分化間充質(zhì)細(xì)胞、衰老的成纖維細(xì)胞以及上皮間質(zhì)轉(zhuǎn)化細(xì)胞,即通過間質(zhì)-間質(zhì)轉(zhuǎn)化(mesenchymal to mes-enchymal,MMT)、上皮-間質(zhì)轉(zhuǎn)化(epithelial-mesenchymal transition,EMT)、內(nèi)皮-間質(zhì)轉(zhuǎn)化(endothelial to mesenchymal,EnMT)而來。首先,局部的成纖維細(xì)胞是CAFs的主要來源,腫瘤微環(huán)境中的成纖維細(xì)胞被腫瘤細(xì)胞分泌的生長因子,如轉(zhuǎn)化生長因子-β(transforming growth factor-β,TGF-β)、PDGF、堿性成纖維因子(basic Fibroblast Growth Factor,bFGF)等激活,發(fā)生間質(zhì)-間質(zhì)轉(zhuǎn)換,同樣的情況也可見于周細(xì)胞;其次,骨髓間充質(zhì)干細(xì)胞(bone marrow mesenchymal stem cells,MSCs)也被認(rèn)為是CAFs的重要來源,它具有強(qiáng)大的增殖能力和多向分化潛能,在適宜的體內(nèi)或體外環(huán)境下不僅可分化為造血細(xì)胞,還能分化為骨、脂肪、軟骨及肌肉細(xì)胞[14-15]。近年來研究發(fā)現(xiàn)將MSCs長時間暴露于腫瘤細(xì)胞中培養(yǎng),能表現(xiàn)出CAFs的相關(guān)表型,包括表達(dá)FSP1、α-SMA,因此 MSCs極有可能是 CAFs的來源之一[16];再者CAFs可由正常上皮細(xì)胞或惡性上皮細(xì)胞發(fā)生上皮-間質(zhì)轉(zhuǎn)化而來[17]。研究發(fā)現(xiàn)暴露在基質(zhì)金屬蛋白酶-3(matrix metalloproteinase-3,MMP-3)誘導(dǎo)的氧化應(yīng)激反應(yīng)中的正常上皮細(xì)胞發(fā)生了基因突變,通過上皮間質(zhì)轉(zhuǎn)化為肌成纖維細(xì)胞(Myofibroblasts)[18];惡性上皮細(xì)胞被 PDGF、TGF-β、表皮生長因子(epidermal growth factor,EGF)等生長因子激活發(fā)生 EMT,并被相關(guān)轉(zhuǎn)錄因子如 Snail、Slug、Twist等調(diào)節(jié)[19]。同樣與上皮細(xì)胞發(fā)生上皮-間質(zhì)轉(zhuǎn)化過程相類似,內(nèi)皮細(xì)胞也可發(fā)生內(nèi)皮-間質(zhì)轉(zhuǎn)化,成為 CAFs的來源。研究發(fā)現(xiàn)[20]在 TGF-β誘導(dǎo)下,內(nèi)皮細(xì)胞不表達(dá)內(nèi)皮細(xì)胞標(biāo)志物CD31,而表達(dá)間質(zhì)標(biāo)志物FSP-1及α-SMA,此結(jié)果支持該觀點(diǎn)。
近年來許多研究證實(shí)CAFs能促進(jìn)腫瘤細(xì)胞的生長、血管生成、侵襲、轉(zhuǎn)移[13]。CAFs還可通過旁分泌的方式分泌多種可溶性因子同腫瘤細(xì)胞及腫瘤間質(zhì)中的其他細(xì)胞發(fā)生相互作用,促進(jìn)腫瘤的發(fā)生、生長、侵襲及轉(zhuǎn)移。
許多研究證實(shí)成纖維細(xì)胞直接參與腫瘤發(fā)生,可以誘發(fā)和促進(jìn)上皮細(xì)胞發(fā)生惡性轉(zhuǎn)化。Kuperwasser證實(shí)小鼠成纖維細(xì)胞過度表達(dá)TGF-β,可誘導(dǎo)發(fā)生乳腺導(dǎo)管癌[21]。在乳腺癌中,CAFs可高表達(dá) α-平滑肌肌動蛋白(達(dá) 53.33 ± 2.33%),培養(yǎng)CAFs的上清液能誘導(dǎo)乳腺癌干細(xì)胞的產(chǎn)生(CAFs組的MCF-7干細(xì)胞比例和MDA-MB-468干細(xì)胞比例分別為對照組的 3.51 和 4.76 倍)[22]。近來Erez[8]報(bào)道利用小鼠皮膚鱗狀細(xì)胞癌模型,從異型性皮膚中分離的CAFs中發(fā)現(xiàn)了促炎細(xì)胞因子,如IL-6、IL-1β、COX-2等,其促炎癥的特性一直維持到隨后形成的皮膚癌中,在促腫瘤的炎癥微環(huán)境形成中發(fā)揮著重要作用;隨后,該研究團(tuán)隊(duì)還發(fā)現(xiàn)乳腺癌及膀胱癌相關(guān)成纖維細(xì)胞高表達(dá)的促腫瘤炎癥因子IL-6,COX-2及 CXCL1的分泌[23]。
腫瘤在生長到直徑超過1~2mm后,繼續(xù)生長則有賴于腫瘤間質(zhì)。CAFs可促進(jìn)腫瘤細(xì)胞增殖、腫瘤血管形成。在前列腺癌的研究中發(fā)現(xiàn),CAFs通過分泌CXCL1促進(jìn)自身的增殖及遷移能力,從而增加CAFs促進(jìn)腫瘤細(xì)胞生長、血管生成及巨噬細(xì)胞浸潤的能力[24];CAFs還能分泌尿激酶型纖溶蛋白酶原激活物(uPA)及其受體(uPAR),誘導(dǎo)腫瘤細(xì)胞的旁分泌產(chǎn)生成纖維細(xì)胞生長因子及內(nèi)皮生長因子,反過來促進(jìn)CAFs中uPA的轉(zhuǎn)錄,在腫瘤細(xì)胞的增殖、侵襲、轉(zhuǎn)移過程中發(fā)揮作用[25]。CAFs促進(jìn)腫瘤血管形成的作用與其分泌的間質(zhì)細(xì)胞源性因子-1有關(guān),該因子作用于血管內(nèi)皮細(xì)胞的同源受體趨化因子受體4(CXCR4),聚集血管內(nèi)皮細(xì)胞祖細(xì)胞,促進(jìn)腫瘤血管形成,從而在腫瘤演進(jìn)過程中發(fā)揮重要作用。在多種人腫瘤細(xì)胞中發(fā)現(xiàn),高表達(dá)的CXCR4與臨床預(yù)后不良相關(guān)。
腫瘤轉(zhuǎn)移灶中的CAFs與原發(fā)部位一樣,可以促進(jìn)腫瘤增殖和生長。在乳腺癌中,CAFs分泌的肝細(xì)胞生長因子(hepatocyte growth factor,HGF)激活腫瘤細(xì)胞表面的c-met分子,增強(qiáng)腫瘤細(xì)胞的侵襲和轉(zhuǎn)移能力[26];CAFs源性的 SDF-1(stromal derived factor 1)在腫瘤的生長和轉(zhuǎn)移上發(fā)揮作用;SDF-1α又稱為CXCL12,是CXCR4的配體,SDF-1/CXCR4生物軸在腫瘤的發(fā)病機(jī)制中起著重要的作用,它能增加腫瘤生長能力及惡性程度,并且能夠促進(jìn)腫瘤血管生成,細(xì)胞膜高表達(dá)CXCR4的腫瘤比低表達(dá)的腫瘤更容易發(fā)生轉(zhuǎn)移[22];通過分泌MMP-13能促進(jìn)細(xì)胞外基質(zhì)(ECM)釋放血管內(nèi)皮生長因子,從而增強(qiáng)黑色素瘤或者鱗狀細(xì)胞癌的侵襲性[24];另外,CAFs可通過促進(jìn)膠原沉積、調(diào)節(jié)膠原纖維間的交聯(lián),改變細(xì)胞外基質(zhì)的結(jié)構(gòu),促進(jìn)腫瘤的進(jìn)展及轉(zhuǎn)移。在有些腫瘤類型中,尤其是乳腺癌及胰腺癌,CAFs的激活可引起纖維異常增生,與腫瘤的進(jìn)展及不良預(yù)后密切相關(guān)[27]。CAFs促腫瘤的機(jī)制還與上皮-間質(zhì)轉(zhuǎn)換密切相關(guān),前列腺癌相關(guān)成纖維細(xì)胞能分泌大量的MMP-2、MMP-9,可能是通過下調(diào)鈣粘蛋白,誘導(dǎo)腫瘤細(xì)胞的EMT,通過促進(jìn)EMT,上皮細(xì)胞失去了細(xì)胞極性、與基底膜連接等上皮表型,獲得了較高的遷移、侵襲、抗凋亡和降解細(xì)胞外基質(zhì)的能力等間質(zhì)表型。研究發(fā)現(xiàn)CAFs分泌的TGF-β1在EMT中起重要作用,它可促進(jìn)上皮細(xì)胞喪失上皮表型的能力。TGF-β1/Smads信號通路誘導(dǎo)下游轉(zhuǎn)錄因子Snail,導(dǎo)致EMT蛋白質(zhì)組的表達(dá),促進(jìn)EMT的發(fā)生。此外,EMT還可通過產(chǎn)生活性氧來誘導(dǎo)腫瘤干細(xì)胞表型的表達(dá),因此EMT是上皮細(xì)胞來源的惡性腫瘤細(xì)胞獲得遷移和侵襲能力的重要生物學(xué)過程[28-29]。有研究表明原發(fā)腫瘤部位的基質(zhì)成分包括CAFs會隨同腫瘤細(xì)胞到達(dá)轉(zhuǎn)移部位,為轉(zhuǎn)移的腫瘤細(xì)胞提供適合其生長的“優(yōu)良”的生長土壤[30]。
從以上研究中不難得知,腫瘤的進(jìn)展需要CAFs與腫瘤細(xì)胞間相互應(yīng)答,腫瘤細(xì)胞誘導(dǎo)和保持成纖維細(xì)胞的激活狀態(tài),同時,CAFs產(chǎn)生一系列的溶解因子通過促進(jìn)腫瘤細(xì)胞的增殖、血管生成及上皮間質(zhì)轉(zhuǎn)化等在腫瘤進(jìn)展中發(fā)揮重要作用。
CAFs成為未來腫瘤靶向治療的理想靶點(diǎn)主要有以下幾個優(yōu)點(diǎn):①腫瘤細(xì)胞與CAFs“對話”的相關(guān)因子在腫瘤的生長、侵襲、轉(zhuǎn)移中有重要作用;②與腫瘤細(xì)胞相比CAFs基因表達(dá)穩(wěn)定,不易出現(xiàn)突變和耐藥發(fā)生;③是組成腫瘤細(xì)胞外基質(zhì)結(jié)構(gòu)的各種成分(如膠原)的主要來源,而細(xì)胞外基質(zhì)又是阻礙抗腫瘤藥物進(jìn)入腫瘤組織的重要屏障;④化療及放療都可能會導(dǎo)致組織的纖維化,因此需要新的輔助治療來針對纖維化以及鑲嵌在纖維化組織中的腫瘤細(xì)胞。以CAFs及其分泌的相關(guān)因子為靶點(diǎn)進(jìn)行的靶向治療,為腫瘤的治療帶來了新的希望[13,31]。
以CAFs作為腫瘤靶向治療靶點(diǎn)可以從以下幾個方面考慮。首先,減少CAFs的來源,可通過阻斷活化CAFs的相關(guān)因子或者信號通路;其次,抑制CAFs的增殖,促進(jìn)其凋亡,減少腫瘤微環(huán)境中CAFs的數(shù)量;再者,減少CAFs與腫瘤細(xì)胞間“對話”的相關(guān)因子,抑制腫瘤細(xì)胞的增殖、侵襲和轉(zhuǎn)移。
針對HGF/MET信號通路的靶向治療藥NK4已經(jīng)進(jìn)入臨床前期研究,它是MET的競爭性拮抗劑和HGF的多克隆抗體,研究表明NK4能顯著減少腫瘤細(xì)胞轉(zhuǎn)移及生長[32]。臨床前期試驗(yàn)中,uPA的抑制劑PAI-1及放射性標(biāo)記的PAI-1能抑制腫瘤的生長及侵襲[33]。FAP在成纖維細(xì)胞的分化中發(fā)揮重要作用,在90%的CAFs中有表達(dá),是CAFs的重要生物學(xué)標(biāo)志,抗FAP抗體sibrotuzumab已進(jìn)入Ⅰ期臨床試驗(yàn),受試者包括FAP陽性的結(jié)腸癌、非小細(xì)胞肺癌患者,證實(shí)其使用是安全的[34]。血管生成抑制劑trombospondin-1抑制宮頸癌的同時,能減少CAFs標(biāo)志物α-SMA的表達(dá)[35]。牙周粘膜成纖維細(xì)胞通過與口腔鱗癌細(xì)胞相互作用誘導(dǎo)CAFs的生成,而姜黃素以兩者間的相互作用為靶點(diǎn),通過抑制促上皮間質(zhì)轉(zhuǎn)化調(diào)節(jié)因子的表達(dá)(SDF-1α、BDNF),逆轉(zhuǎn)腫瘤細(xì)胞的上皮間質(zhì)轉(zhuǎn)換過程,從而降低腫瘤細(xì)胞的侵襲性[36]。
CAFs在腫瘤微環(huán)境中與腫瘤相互作用,表達(dá)多種細(xì)胞因子、蛋白酶、粘附因子,不同程度增加了腫瘤細(xì)胞的發(fā)生、生長、血管形成、浸潤及轉(zhuǎn)移,雖然其來源、以及如何促進(jìn)腫瘤發(fā)生發(fā)展的機(jī)制尚有待研究。但是以CAFs異常作為診斷腫瘤發(fā)生的指標(biāo),并將其作為新的抗癌治療的靶點(diǎn),結(jié)合放療、化療和外科手術(shù)治療癌癥的新療法已受到越來越多的關(guān)注。此外,CAFs還與腫瘤預(yù)后有密切關(guān)系,可能成為一些腫瘤新的預(yù)后指標(biāo)。總之,繼續(xù)深入研究CAFs與腫瘤細(xì)胞的相互作用,有利于更全面地認(rèn)識腫瘤發(fā)生發(fā)展的機(jī)制,為臨床治療提供更充分的理論和實(shí)驗(yàn)依據(jù)。
[1] Xing F, Saidou J,Watabe K.Cancer associated fibroblast(CAFs)in tumor microenvironment[J].Front Biosci(Landmark Ed),2010,15(1):166-179.
[2] Augsten M,H?ggl?f C,Pe?a C,et al.A digest on the role of the tumor microenvironment in gastrointestinal cancers[J].Cancer Microenviron,2010,3(1):167-176.
[3] Kim SH,Choe C,Shin YS,et al.Human lung cancer-associated fibroblasts enhance motility of non-small cell lung cancer cells in co-culture[J].Anticancer Res,2013,33(5):2001-2009.
[4] Gabbiani G,Ryan GB,Majne G.Presence of modified fibroblasts in granulation tissue and their possible role in wound contraction[J].Experientia,1971,27(5):549-550.
[5] Dvorak HF.Tumors:wounds that do not heal.similarities between tumor stroma generation and wound healing[J].N Engl J Med,1986,315(26):1650-1659.
[6] Oliumi AF,Grossfeld GD,Hayward SW,et al.Carcinoma-associ-ated fibroblasts direct tumor progression of initiated human prostatic epithelium[J].Cancer Res,1999,59(19):5002-5011.
[7] Zhi K,Shen X,Bi J.Cancer-associated fibroblasts are positively correlated with metastatic potential of human gastric cancers[J].J Exp Clin Cancer Res,2010,29(1):66.
[8] Erez N,Truitt M,Olson P,et al.Cancer-associated fibroblasts are activated in incipient neoplasia to orchestrate tumor-promoting inflammation in an NF-kappaB-dependent manner[J].Cancer Cell,2010,17(2):135-147.
[9] Anderberg C,Li H,F(xiàn)redriksson L,et al.Paracrine signaling by platelet-derived growth factor-CC promotes tumor growth by recruitment of cancer-associated fibroblasts[J].Cancer Res,2009,69(1):369-378.
[10] Sherbet GV.Metastasis promoter S100A4 is a potentially valuable molecular target for cancer therapy[J].Cancer Lett,2009,280(1):15-30.
[11] Brennen WN,Isaacs JT,Denmeade SR.Rationale behind targeting fibroblast activation protein-expressing carcinoma-associated fibroblasts as a novel chemotherapeutic strategy[J].Mol Cancer Ther,2012,11(2):257-266.
[12] Ostman A.PDGF receptors-mediators of autocrine tumor growth and regulators of tumor vasculature and stroma[J].Cytokine Growth Factor Rev,2004,15(4):275-286.
[13] Cirri P,Chiarugi P.Cancer associated fibroblasts:the dark side of the coin[J].Am J Cancer Res,2011,1(4):482-497.
[14] Bergfeld SA,DeClerck YA.Bone marrow-derived mesenchymal stem cells and the tumor microenvironment[J].Cancer Metastasis Rev,2010,29(2):249-261.
[15] Quante M,Tu SP,Tomita H,et al.Bone marrow-derived myofibroblasts contribute to the mesenchymal stem cell niche and promote tumor growth[J].Cancer Cell,2011,19(2):257-272.
[16] Mishra PJ,Mishra PJ,Humeniuk R,et al.Carcinoma-associated fibroblast-like differentiation of human mesenchymal stem cells[J].Cancer Res,2008,68(11):4331-4339.
[17] Astekar M,Metgud R,Sharma A,et al.Hidden keys in stroma:unlocking the tumor progression[J].J Oral Maxillofac Pathol,2013,17(1):82-88.
[18] Radisky DC,Levy DD,Littlepage LE,et al.Rac1b and reactive oxygen species mediate MMP-3-induced EMT and genomic instability[J].Nature,2005,436(7047):123-127.
[19] Kalluri R,Weinberg RA.The basics of epithelial-mesenchymal transition[J].J Clin Invest,2009,119(6):1420-1428.
[20] Zeisberg EM,Potenta S,Xie L,et al.Discovery of endothelial to mesenchymal transition as a source for carcinoma-associated fibroblasts[J].Cancer Res,2007,67(21):10123-10128.
[21] Jeleszk c,Victor B,Podgorski.Fibroblast hepatocyte growth factor promotes invasion of human mammary ductal carcinoma in situ[J].Cancer Res,2009,69(23):9148-9155.
[22] Orimo A,Gupta PB,Sgroi DC,et al.Stromal fibroblasts present in invasive human breast carcinomas promote tumor growth and angiogenesis through elevated SDF-1/CXCL12 secretion[J].Cell,2005,121(3):335-348.
[23] Augsten M,Hagglof C,Olsson E,et al.CXCL14 is an autocrine growth factor for fibroblasts and acts as a multi-modal stimulator of prostate tumor growth[J].Proc Natl Acad Sci USA,2009,106(9):3414-3419.
[24] Lederle W,Hartenstein B,Meides A,et al.MMP13 as a stromal mediator in controlling persistent angiogenesis in skin carcinoma[J].Carcinogenesis,2010,31(7):1175-1184.
[25] Noskova V,Ahmadi S,Asander E,et al.Ovarian cancer cells stimulate uPA gene expression in fibroblastic stromal cells via multiple paracrine and autocrine mechanisms[J].Gynecol Oncol,2009,115(1):121-126.
[26] Erez N,Glanz S,Raz Y,et al.Cancer associated fibroblasts express pro-inflammatory factors in human breast and ovarian tumors[J].Biochem Bioph Res Co,2013,437(3):397-402.
[27] Goetz JG,Minguet S,Navarro-Lerida I,et al.Biomechanical remodeling of the microenvironment by stromal caveolin-1 favors tumor invasion and metastasis[J].Cell,2011,146(1):148-163.
[28] Thiery JP,Acloque H,Huang RY,et al.Epithelial-mesenchymal transitions in development and disease[J].Cell,2009,139(5):871-890.
[29] Giannoni E,Bianchini F,Masieri L,et al.Reciprocal activation of prostate cancer cells and cancer-associated fibroblasts stimulates epithelial-mesenchymal transition and cancer stemness[J].Cancer Res,2010,70(17):6945-6956.
[30] Duda DG,Duyverman AM,Kohno M,et al.Malignant cells facilitate lung metastasis by bringing[J].Proc Natl Acad Sci USA,2010,107(50):21677-21682.
[31] Harless WW.Revisiting perioperative chemotherapy:the critical importance of targeting residual cancer prior to wound healing[J].BMC Cancer,2009,22(9):118.
[32] Wang W,Li Q,Yamada T,et al.Crosstalk to stromal fibroblasts induces resistance of lung cancer to epidermal growth factor receptor tyrosine kinase inhibitors[J].Clin Cancer Res,2009,15(21):6630-6638.
[33] Qu CF,Song EY,Li Y,et al.Pre-clinical study of 213Bi labeled PAI2 for the control of micrometastatic pancreatic cancer[J].Clin Exp Metastasis,2005,22(7):575-562.
[34] Scott AM,Wiseman G,Welt S,et al.A Phase I dose-escalation study of sibrotuzumab in patients with advanced or metastatic fibroblast activation protein-positive cancer[J].Clin Cancer Res,2003,9(5):1639-1647.
[35] Wu MP,Young MJ,Tzeng CC,et al.A novel role of thrombospondin-1 in cervical carcinogenesis:inhibit stroma reaction by inhibiting activated fibroblasts from invading cancer[J].Carcinogenesis,2008,29(6):1115-1123.
[36] Dudás J,F(xiàn)ullár A,Romani A,et al.Curcumin targets fibroblast-tumor cell interactions in oral squamous cell carcinoma[J].Exp Cell Res,2012,319(6):800-809.