Cholangiocarcinoma tumor microenvironment highlighting fibrosis and matrix components

Abstract

Cholangiocarcinoma (CCA) is an extremely aggressive malignancy characterized by a very limited prognosis and scarce treatment options. The majority of patients are diagnosed at an advanced stage and do not qualify for potentially curative surgical treatments, making CCA an increasingly prevalent global challenge. CCA is characterized by a highly reactive desmoplastic stroma, with complex mechanisms underlying the mutual interactions between tumor cells and stromal compartment. This review focuses on the recent studies examining CCA’s biological features, with particular reference to the tumor reactive stroma (TRS) and its role in CCA progression, including matrix remodeling, angiogenesis and lymphangiogenesis, metastasis, and immune evasion. After giving a panoramic view of the relationship between the tumoral and stromal compartment (cancer-associated fibroblast, CAFs and tumor-associated macrophages, TAMs), this review also discusses the current therapeutic approaches to counteract CAFs and TAMs effects on CCA progression.

Keywords

Tumor microenvironments / CAFs / TAMs / CCA / tumor-reactive stroma / therapeutic target

References

[1] DeOliveira ML,Cameron JL.Cholangiocarcinoma: thirty-one-year experience with 564 patients at a single institution.Ann Surg2007;245:755-62. PMCID:PMC1877058

[2] Khan SA,Brandi G.Cholangiocarcinoma: epidemiology and risk factors.Liver Int2019;39 Suppl 1:19-31

[3] Brindley PJ,Ilyas SI.Cholangiocarcinoma.Nat Rev Dis Primers2021;7:65 PMCID:PMC9246479

[4] Wang Y,Shen C.Surgical procedure and long-term survival of hilar cholangiocarcinoma.Int J Clin Exp Med2015;8:1122-8 PMCID:PMC4358557

[5] Homayounfar K,Cameron S.Pattern of chromosomal aberrations in primary liver cancers identified by comparative genomic hybridization.Hum Pathol2009;40:834-42

[6] Uhm KO,Lee JY,Park SH.Chromosomal imbalances in Korean intrahepatic cholangiocarcinoma by comparative genomic hybridization.Cancer Genet Cytogenet2005;157:37-41

[7] Vilà P, Ravichandra A, Agirre Lizaso A, Perugorria MJ, Affò S. Heterogeneity, crosstalk, and targeting of cancer-associated fibroblasts in cholangiocarcinoma.Hepatology2023;Online ahead of print:

[8] Nakazawa K,Suzuki S,Takeda Y.Amplification and overexpression of c-erbB-2, epidermal growth factor receptor, and c-met in biliary tract cancers.J Pathol2005;206:356-65

[9] Brandi G,Astolfi A,Tavolari S.Genetic heterogeneity in cholangiocarcinoma: a major challenge for targeted therapies.Oncotarget2015;6:14744-53 PMCID:PMC4558112

[10] O'Rourke CJ,Aguayo EL.Epigenome dysregulation in cholangiocarcinoma.Biochim Biophys Acta Mol Basis Dis2018;1864:1423-34.

[11] Chen Z,Xie X,Wang Y.The role of tumour microenvironment: a new vision for cholangiocarcinoma.J Cell Mol Med2019;23:59-69. PMCID:PMC6307844

[12] Leyva-Illades D,Quinn M.Cholangiocarcinoma pathogenesis: role of the tumor microenvironment.Transl Gastrointest Cancer2012;1:71-80 PMCID:PMC3448449

[13] Kai F,Weaver VM.The extracellular matrix modulates the metastatic journey.Dev Cell2019;49:332-46 PMCID:PMC6527347

[14] Wang J.Targeting the tumor microenvironment in cholangiocarcinoma: implications for therapy.Expert Opin Investig Drugs2021;30:429-38 PMCID:PMC8096665

[15] Naba A,Ding H,Carr SA.The extracellular matrix: tools and insights for the "omics" era.Matrix Biol2016;49:10-24. PMCID:PMC5013529

[16] Mouw JK,Weaver VM.Extracellular matrix assembly: a multiscale deconstruction.Nat Rev Mol Cell Biol2014;15:771-85 PMCID:PMC4682873

[17] Hastings JF,Fey D,Cox TR.The extracellular matrix as a key regulator of intracellular signalling networks.Br J Pharmacol2019;176:82-92. PMCID:PMC6284331

[18] Cox TR.Remodeling and homeostasis of the extracellular matrix: implications for fibrotic diseases and cancer.Dis Model Mech2011;4:165-78. PMCID:PMC3046088

[19] Doyle AD,Yamada KM.Cell-extracellular matrix dynamics.Phys Biol2022;19:021002 PMCID:PMC8855216

[20] Giancotti FG.Integrin signaling.Science1999;285:1028-32.

[21] Winkler J,Metcalf KJ.Concepts of extracellular matrix remodelling in tumour progression and metastasis.Nat Commun2020;11:5120 PMCID:PMC7547708

[22] Awaji M,Wu L.CXCR2 signaling promotes secretory cancer-associated fibroblasts in pancreatic ductal adenocarcinoma.FASEB J2020;34:9405-18. PMCID:PMC7501205

[23] Colyn L,Latasa MU.New molecular mechanisms in cholangiocarcinoma: signals triggering interleukin-6 production in tumor cells and KRAS co-opted epigenetic mediators driving metabolic reprogramming.J Exp Clin Cancer Res2022;41:183 PMCID:PMC9134609

[24] Kessenbrock K,Werb Z.Matrix metalloproteinases: regulators of the tumor microenvironment.Cell2010;141:52-67 PMCID:PMC2862057

[25] Sirica AE.Desmoplastic stroma and cholangiocarcinoma: clinical implications and therapeutic targeting.Hepatology2014;59:2397-402 PMCID:PMC3975806

[26] Subrungruanga I,Chawalitchewinkoon-Petmitrc P,Wongkham S.Gene expression profiling of intrahepatic cholangiocarcinoma.Asian Pac J Cancer Prev2013;14:557-63

[27] Islam K,Kaewkong P,Suthiphongchai T.Role of laminin and cognate receptors in cholangiocarcinoma cell migration.Cell Adh Migr2021;15:152-65 PMCID:PMC8143218

[28] Liu W,Jiang P.Aberrant expression of laminin γ2 correlates with poor prognosis and promotes invasion in extrahepatic cholangiocarcinoma.J Surg Res2014;186:150-6

[29] Li Y,Chen J.Expression of lamininγ2 in extrahepatic cholangiocarcinoma tissues and its influence on tumor invasion and metastasis.Asian Pac J Cancer Prev2015;16:2099-102

[30] Aishima S,Terashi T.Aberrant expression of laminin gamma 2 chain and its prognostic significance in intrahepatic cholangiocarcinoma according to growth morphology.Mod Pathol2004;17:938-45

[31] Pei YF,Cheng J,Liu XQ.Silencing of LAMC2 reverses epithelial-mesenchymal transition and inhibits angiogenesis in cholangiocarcinoma via inactivation of the epidermal growth factor receptor signaling pathway.Am J Pathol2019;189:1637-53

[32] Yoo HJ,Kwon JH.Genetic and expression alterations in association with the sarcomatous change of cholangiocarcinoma cells.Exp Mol Med2009;41:102-15 PMCID:PMC2679331

[33] Ding YB,Huang YS.A high level of integrin α6 expression in human intrahepatic cholangiocarcinoma cells is associated with a migratory and invasive phenotype.Dig Dis Sci2013;58:1627-35

[34] Soejima Y,Takahashi Y,Sawabe M.Integrins αvβ6, α6β4 and α3β1 are down-regulated in cholangiolocellular carcinoma but not cholangiocarcinoma.Hepatol Res2014;44:E320-34

[35] Li D,Gao Z.67-kDa laminin receptor in human bile duct carcinoma.Eur Surg Res2009;42:168-73

[36] Neve A,Maruotti N,Ribatti D.Extracellular matrix modulates angiogenesis in physiological and pathological conditions.Biomed Res Int2014;2014:756078 PMCID:PMC4052469

[37] Lv H,Sun L,Zhao X.Elevate level of glycosaminoglycans and altered sulfation pattern of chondroitin sulfate are associated with differentiation status and histological type of human primary hepatic carcinoma.Oncology2007;72:347-56

[38] Nagarajan A,Wajapeyee N.Heparan sulfate and heparan sulfate proteoglycans in cancer initiation and progression.Front Endocrinol2018;9:483. PMCID:PMC6118229

[39] Sabit H,Shimonishi T.Enhanced expression of basement-membrane-type heparan sulfate proteoglycan in tumor fibro-myxoid stroma of intrahepatic cholangiocarcinoma.Pathol Int2001;51:248-56

[40] Batmunkh E,Szabó E.Comparison of the expression of agrin, a basement membrane heparan sulfate proteoglycan, in cholangiocarcinoma and hepatocellular carcinoma.Hum Pathol2007;38:1508-15.

[41] Hynes RO.The extracellular matrix: not just pretty fibrils.Science2009;326:1216-9 PMCID:PMC3536535

[42] Huleihel L,Naranjo JD.Matrix-bound nanovesicles within ECM bioscaffolds.Sci Adv2016;2:e1600502 PMCID:PMC4928894

[43] Martino MM.The 12th-14th type III repeats of fibronectin function as a highly promiscuous growth factor-binding domain.FASEB J2010;24:4711-21.

[44] Mott JD.Regulation of matrix biology by matrix metalloproteinases.Curr Opin Cell Biol2004;16:558-64 PMCID:PMC2775446

[45] Wells JM,Blalock JE.MMP generated matrikines.Matrix Biol2015;44-46:122-9 PMCID:PMC4838901

[46] Perez S.The clinician and caries. Self-test of his diagnostic method.Chir Dent Fr1989;59:35-7

[47] Sun Q,Xia L.High expression of matrix metalloproteinase-9 indicates poor prognosis in human hilar cholangiocarcinoma.Int J Clin Exp Pathol2014;7:6157-64

[48] Kirimlioğlu H,Başsüllü N,Karadağ N.The expression of matrix metalloproteinases in intrahepatic cholangiocarcinoma, hilar (Klatskin tumor), middle and distal extrahepatic cholangiocarcinoma, gallbladder cancer, and ampullary carcinoma: role of matrix metalloproteinases in tumor progression and prognosis.Turk J Gastroenterol2009;20:41-7

[49] Prakobwong S,Hiraku Y.Involvement of MMP-9 in peribiliary fibrosis and cholangiocarcinogenesis via Rac1-dependent DNA damage in a hamster model.Int J Cancer2010;127:2576-87

[50] Pak JH,Song IS,Jang SW.Clonorchis sinensis excretory-secretory products regulate migration and invasion in cholangiocarcinoma cells via extracellular signal-regulated kinase 1/2/nuclear factor-κB-dependent matrix metalloproteinase-9 expression.Int J Parasitol2017;47:51-9

[51] Lin HY,Yang YL,Hsiau YT.Roles of lysyl oxidase family members in the tumor microenvironment and progression of liver cancer.Int J Mol Sci2020;21:9751 PMCID:PMC7766343

[52] Bergeat D,Turlin B.Impact of stroma LOXL2 overexpression on the prognosis of intrahepatic cholangiocarcinoma.J Surg Res2016;203:441-50.

[53] Xu J,Li X.67 laminin receptor promotes the malignant potential of tumour cells up-regulating lysyl oxidase-like 2 expression in cholangiocarcinoma.Dig Liver Dis2014;46:750-7

[54] Peng T,Tian F.The interaction of LOXL2 with GATA6 induces VEGFA expression and angiogenesis in cholangiocarcinoma.Int J Oncol2019;55:657-70 PMCID:PMC6685595

[55] Chakraborty S,Hong W.Agrin mediates angiogenesis in the tumor microenvironment.Trends Cancer2020;6:81-5

[56] Sirica AE.Matricellular proteins in intrahepatic cholangiocarcinoma. Hepatobiliary cancers: translational advances and molecular medicine. Elsevier; 2022. pp. 249-81.

[57] Albrengues J,Ng D.Neutrophil extracellular traps produced during inflammation awaken dormant cancer cells in mice.Science2018;361:eaao4227 PMCID:PMC6777850

[58] Tomasek JJ,Hinz B,Brown RA.Myofibroblasts and mechano-regulation of connective tissue remodelling.Nat Rev Mol Cell Biol2002;3:349-63

[59] Strutz F,Lo CW.Identification and characterization of a fibroblast marker: FSP1.J Cell Biol1995;130:393-405 PMCID:PMC2199940

[60] Nishihara Y,Hayashi A.CD10⁺ fibroblasts are more involved in the progression of hilar/extrahepatic cholangiocarcinoma than of peripheral intrahepatic cholangiocarcinoma.Histopathology2009;55:423-31

[61] Pietras K,Rubin K,Ostman A.PDGF receptors as cancer drug targets.Cancer Cell2003;3:439-43

[62] Augsten M.Cancer-associated fibroblasts as another polarized cell type of the tumor microenvironment.Front Oncol2014;4:62 PMCID:PMC3973916

[63] Lyons L.Profile of liz lyons: age is a state of mind.Gerontion1986;1:32-4.

[64] Zhang XF,Pan YH.Expression pattern of cancer-associated fibroblast and its clinical relevance in intrahepatic cholangiocarcinoma.Hum Pathol2017;65:92-100

[65] Chuaysri C,Paupairoj A,Suthiphongchai T.Alpha-smooth muscle actin-positive fibroblasts promote biliary cell proliferation and correlate with poor survival in cholangiocarcinoma.Oncol Rep21:957-69.

[66] Sha M,Qiu BJ.Isolation of cancer-associated fibroblasts and its promotion to the progression of intrahepatic cholangiocarcinoma.Cancer Med2018;7:4665-77 PMCID:PMC6144256

[67] Fabris L,Alpini G.The tumor microenvironment in cholangiocarcinoma progression.Hepatology2021;73 Suppl 1:75-85 PMCID:PMC7714713

[68] Franco OE,Strand DW.Cancer associated fibroblasts in cancer pathogenesis.Semin Cell Dev Biol2010;21:33-9 PMCID:PMC2823834

[69] Montori M,Argenziano ME.Cancer-Associated fibroblasts in cholangiocarcinoma: current knowledge and possible implications for therapy.J Clin Med2022;11:6498 PMCID:PMC9654416

[70] Affo S,Brundu F.Promotion of cholangiocarcinoma growth by diverse cancer-associated fibroblast subpopulations.Cancer Cell2021;39:866-882.e11. PMCID:PMC8241235

[71] Zhang M,Wan L.Single-cell transcriptomic architecture and intercellular crosstalk of human intrahepatic cholangiocarcinoma.J Hepatol2020;73:1118-30

[72] Itou RA,Hirota S.Immunohistochemical characterization of cancer-associated fibroblasts at the primary sites and in the metastatic lymph nodes of human intrahepatic cholangiocarcinoma.Hum Pathol2019;83:77-89.

[73] Yangngam S,Pongpaibul A.High level of interleukin-33 in cancer cells and cancer-associated fibroblasts correlates with good prognosis and suppressed migration in cholangiocarcinoma.J Cancer2020;11:6571-81. PMCID:PMC7545672

[74] Miyata T,Yoshizumi T.CXCL12 expression in intrahepatic cholangiocarcinoma is associated with metastasis and poor prognosis.Cancer Sci2019;110:3197-203 PMCID:PMC6778649

[75] Gentilini A,Marra F.The role of stroma in cholangiocarcinoma: the intriguing interplay between fibroblastic component, immune cell subsets and tumor epithelium.Int J Mol Sci2018;19:2885 PMCID:PMC6213545

[76] Cadamuro M,Indraccolo S.Platelet-derived growth factor-D and Rho GTPases regulate recruitment of cancer-associated fibroblasts in cholangiocarcinoma.Hepatology2013;58:1042-53 PMCID:PMC3732815

[77] Cadamuro M,Mertens J.Platelet-derived growth factor-D enables liver myofibroblasts to promote tumor lymphangiogenesis in cholangiocarcinoma.J Hepatol2019;70:700-9

[78] Fingas CD,Werneburg NW.Myofibroblast-derived PDGF-BB promotes hedgehog survival signaling in cholangiocarcinoma cells.Hepatology2011;54:2076-88 PMCID:PMC3230714

[79] Clapéron A,Aoudjehane L.Hepatic myofibroblasts promote the progression of human cholangiocarcinoma through activation of epidermal growth factor receptor.Hepatology2013;58:2001-11

[80] Nguyen MLT,Scholta T.Targeting interleukin 6 signaling by monoclonal antibody siltuximab on cholangiocarcinoma.J Gastroenterol Hepatol2021;36:1334-45

[81] Terashita K,Hatanaka Y.ZEB1 expression is associated with prognosis of intrahepatic cholangiocarcinoma.J Clin Pathol2016;69:593-9.

[82] Qin X,Li G,Liu Z.Downregulation of tumor-derived exosomal miR-34c induces cancer-associated fibroblast activation to promote cholangiocarcinoma progress.Cancer Cell Int2021;21:373 PMCID:PMC8278610

[83] Gentilini A,Galastri S.Role of the stromal-derived factor-1 (SDF-1)-CXCR4 axis in the interaction between hepatic stellate cells and cholangiocarcinoma.J Hepatol2012;57:813-20

[84] Gentilini A,Raggi C.CXCR7 contributes to the aggressive phenotype of cholangiocarcinoma cells.Biochim Biophys Acta Mol Basis Dis2019;1865:2246-56

[85] Ohira S,Harada K.Possible regulation of migration of intrahepatic cholangiocarcinoma cells by interaction of CXCR4 expressed in carcinoma cells with tumor necrosis factor-alpha and stromal-derived factor-1 released in stroma.Am J Pathol2006;168:1155-68 PMCID:PMC1606561

[86] Campbell DJ,Lamour NF,Sirica AE.Novel organotypic culture model of cholangiocarcinoma progression.Hepatol Res2012;42:1119-30. PMCID:PMC3416930

[87] Okamoto K,Ohta T.The role of renin-angiotensin system independent angiotensin II production in progression and fibrosis of intrahepatic cholangiocarcinoma.Gan To Kagaku Ryoho2010;37:2231-3. (in Japanese)

[88] Yang X,Shi Y.FAP Promotes Immunosuppression by Cancer-Associated Fibroblasts in the Tumor Microenvironment via STAT3-CCL2 Signaling.Cancer Res2016;76:4124-35

[89] Lin Y,Chen Y.CAFs shape myeloid-derived suppressor cells to promote stemness of intrahepatic cholangiocarcinoma through 5-lipoxygenase.Hepatology2022;75:28-42

[90] Volonte D,Chen C.Caveolin-1 promotes the tumor suppressor properties of oncogene-induced cellular senescence.J Biol Chem2018;293:1794-809. PMCID:PMC5798308

[91] Lan C,Yamashita YI.Cancer-associated fibroblast senescence and its relation with tumour-infiltrating lymphocytes and PD-L1 expressions in intrahepatic cholangiocarcinoma.Br J Cancer2022;126:219-27 PMCID:PMC8770615

[92] Zhou SL,Zhou ZJ.CXCL5 contributes to tumor metastasis and recurrence of intrahepatic cholangiocarcinoma by recruiting infiltrative intratumoral neutrophils.Carcinogenesis2014;35:597-605

[93] Okabe H,Ueda M.Identification of CXCL5/ENA-78 as a factor involved in the interaction between cholangiocarcinoma cells and cancer-associated fibroblasts.Int J Cancer2012;131:2234-41

[94] Cadamuro M,Strazzabosco M.Unveiling the role of tumor reactive stroma in cholangiocarcinoma: an opportunity for new therapeutic strategies.Transl Gastrointest Cancer2013;2:130-44 PMCID:PMC5627657

[95] Thelen A,Weichert W.Tumor-associated angiogenesis and lymphangiogenesis correlate with progression of intrahepatic cholangiocarcinoma.Am J Gastroenterol2010;105:1123-32

[96] Semela D,Langer D,Leof E.Platelet-derived growth factor signaling through ephrin-b2 regulates hepatic vascular structure and function.Gastroenterology2008;135:671-9 PMCID:PMC2639748

[97] Thabut D.Intrahepatic angiogenesis and sinusoidal remodeling in chronic liver disease: new targets for the treatment of portal hypertension?.J Hepatol2010;53:976-80

[98] Andrae J,Betsholtz C.Role of platelet-derived growth factors in physiology and medicine.Genes Dev2008;22:1276-312 PMCID:PMC2732412

[99] Aoki S,Klein S.Placental growth factor promotes tumour desmoplasia and treatment resistance in intrahepatic cholangiocarcinoma.Gut2022;71:185-93. PMCID:PMC8666816

[100] Green CJ,Huynh NT.Placenta growth factor gene expression is induced by hypoxia in fibroblasts: a central role for metal transcription factor-1.Cancer Res2001;61:2696-703

[101] Brivio S,Strazzabosco M.Tumor reactive stroma in cholangiocarcinoma: the fuel behind cancer aggressiveness.World J Hepatol2017;9:455-68 PMCID:PMC5368623

[102] Aishima S,Terashi T,Shimada M.Tenascin expression at the invasive front is associated with poor prognosis in intrahepatic cholangiocarcinoma.Mod Pathol2003;16:1019-27

[103] Hendaoui I,Campo L.Tenascin-W is a novel stromal marker in biliary tract cancers.Front Immunol2020;11:630139 PMCID:PMC7937617

[104] Utispan K,Thuwajit P.Periostin activates integrin α5β1 through a PI3K/AKT-dependent pathway in invasion of cholangiocarcinoma.Int J Oncol2012;41:1110-8

[105] Sonongbua J,Thongchot S.Periostin induces epithelial-to-mesenchymal transition via the integrin α5β1/TWIST-2 axis in cholangiocarcinoma.Oncol Rep2020;43:1147-58 PMCID:PMC7057947

[106] Leavenworth JW,Wang Q,Cantor H.Intracellular osteopontin regulates homeostasis and function of natural killer cells.Proc Natl Acad Sci U S A2015;112:494-9 PMCID:PMC4299239

[107] Klement JD,Redd PS.An osteopontin/CD44 immune checkpoint controls CD8⁺ T cell activation and tumor immune evasion.J Clin Invest2018;128:5549-60 PMCID:PMC6264631

[108] Sulpice L,Desille M.Molecular profiling of stroma identifies osteopontin as an independent predictor of poor prognosis in intrahepatic cholangiocarcinoma.Hepatology2013;58:1992-2000

[109] Zheng Y,Yu XX.Osteopontin promotes metastasis of intrahepatic cholangiocarcinoma through recruiting MAPK1 and mediating Ser675 phosphorylation of β-Catenin.Cell Death Dis2018;9:179 PMCID:PMC5833342

[110] Jing CY,Zhou C.Hepatic stellate cells promote intrahepatic cholangiocarcinoma progression via NR4A2/osteopontin/Wnt signaling axis.Oncogene2021;40:2910-22

[111] Rimassa L,Aghemo A.The immune milieu of cholangiocarcinoma: From molecular pathogenesis to precision medicine.J Autoimmun2019;100:17-26

[112] Subimerb C,Khuntikeo N.Tissue invasive macrophage density is correlated with prognosis in cholangiocarcinoma.Mol Med Rep2010;3:597-605

[113] Paillet J,Pol JG.Immune contexture of cholangiocarcinoma.Curr Opin Gastroenterol2020;36:70-6

[114] Szulc-kielbik I.Tumor-Associated Macrophages: reasons to be cheerful, reasons to be fearful. In: Klink M, Szulc-kielbik I, editors. Interaction of immune and cancer cells. Cham: Springer International Publishing; 2022. pp. 107-40.

[115] Pathria P,Varner JA.Targeting tumor-associated macrophages in cancer.Trends Immunol2019;40:310-27

[116] Høgdall D,Andersen JB.Desmoplastic tumor microenvironment and immunotherapy in cholangiocarcinoma.Trends Cancer2018;4:239-55

[117] Debebe A,Chen CY.Wnt/β-catenin activation and macrophage induction during liver cancer development following steatosis.Oncogene2017;36:6020-9 PMCID:PMC5666317

[118] Loilome W,Techasen A.Activated macrophages promote Wnt/β-catenin signaling in cholangiocarcinoma cells.Tumour Biol2014;35:5357-67. PMCID:PMC4862210

[119] Zhou M,Lu S.Tumor-associated macrophages in cholangiocarcinoma: complex interplay and potential therapeutic target.EBioMedicine2021;67:103375 PMCID:PMC8134032

[120] Boulter L,Kendall TJ.WNT signaling drives cholangiocarcinoma growth and can be pharmacologically inhibited.J Clin Invest2015;125:1269-85. PMCID:PMC4362247

[121] Li X,Peng X.Progress of tumor-associated macrophages in the epithelial-mesenchymal transition of tumor.Front Oncol2022;12:911410. PMCID:PMC9366252

[122] Vakili-Ghartavol R,Salmaninejad A.Tumor-associated macrophages and epithelial-mesenchymal transition in cancer: nanotechnology comes into view.J Cell Physiol2018;233:9223-36

[123] Techasen A,Namwat N,Jongthawin J.Cytokines released from activated human macrophages induce epithelial mesenchymal transition markers of cholangiocarcinoma cells.Asian Pac J Cancer Prev2012;13 Suppl:115-8

[124] Thanee M,Techasen A.Quantitative changes in tumor-associated M2 macrophages characterize cholangiocarcinoma and their association with metastasis.Asian Pac J Cancer Prev2015;16:3043-50

[125] Cadamuro M,Brivio S.The deleterious interplay between tumor epithelia and stroma in cholangiocarcinoma.Biochim Biophys Acta Mol Basis Dis2018;1864:1435-43 PMCID:PMC6386155

[126] Techasen A,Loilome W.Tumor necrosis factor-α modulates epithelial mesenchymal transition mediators ZEB2 and S100A4 to promote cholangiocarcinoma progression.J Hepatobiliary Pancreat Sci2014;21:703-11.

[127] Techasen A,Loilome W.Tumor necrosis factor-α (TNF-α) stimulates the epithelial-mesenchymal transition regulator Snail in cholangiocarcinoma.Med Oncol2012;29:3083-91

[128] Mariotti V,Cadamuro M,Strazzabosco M.New insights on the role of vascular endothelial growth factor in biliary pathophysiology.JHEP Rep2021;3:100251 PMCID:PMC8189933

[129] Subimerb C,Lulitanond V.Circulating CD14⁺CD16⁺ monocyte levels predict tissue invasive character of cholangiocarcinoma.Clin Exp Immunol2010;161:471-9 PMCID:PMC2962964

[130] Hasita H,Okabe H.Significance of alternatively activated macrophages in patients with intrahepatic cholangiocarcinoma.Cancer Sci2010;101:1913-9

[131] Ruffolo LI,Kuhlers PC.GM-CSF drives myelopoiesis, recruitment and polarisation of tumour-associated macrophages in cholangiocarcinoma and systemic blockade facilitates antitumour immunity.Gut2022;71:1386-98 PMCID:PMC8857285

[132] Walter D,Schnitzbauer AA. PD-L1 expression in extrahepatic cholangiocarcinoma.Histopathology2017;71:383-92

[133] Gani F,Kim Y.Program death 1 immune checkpoint and tumor microenvironment: implications for patients with intrahepatic cholangiocarcinoma.Ann Surg Oncol2016;23:2610-7

[134] Kitano Y,Nakao Y.Clinical significance of PD-L1 expression in both cancer and stroma cells of cholangiocarcinoma patients.Ann Surg Oncol2020;27:599-607

[135] Hutchinson JH,Lonergan D.Small molecule lysyl oxidase-like 2 (LOXL2) inhibitors: the identification of an inhibitor selective for LOXL2 over LOX.ACS Med Chem Lett2017;8:423-7 PMCID:PMC5392766

[136] Wong CC,Huang YP.Lysyl oxidase-like 2 is critical to tumor microenvironment and metastatic niche formation in hepatocellular carcinoma.Hepatology2014;60:1645-58

[137] Kato M,Goto Y.Regulation of metastasis-promoting LOXL2 gene expression by antitumor microRNAs in prostate cancer.J Hum Genet2017;62:123-32

[138] Xie L,Jiang ZQ.Comparative study of outer envelope protein and LPS of five strains of leptospires by SDS-PAGE and 2D-PAGE.Hua Xi Yi Ke Da Xue Xue Bao1989;20:361-5

[139] Mertens JC,Christensen JD.Therapeutic effects of deleting cancer-associated fibroblasts in cholangiocarcinoma.Cancer Res2013;73:897-907 PMCID:PMC3549008

[140] Yamanaka T,Yokobori T. Nintedanib inhibits intrahepatic cholangiocarcinoma aggressiveness via suppression of cytokines extracted from activated cancer-associated fibroblasts.Br J Cancer2020;122:986-94 PMCID:PMC7109053

[141] Thongchot S,Vidoni C.Resveratrol interrupts the pro-invasive communication between cancer associated fibroblasts and cholangiocarcinoma cells.Cancer Lett2018;430:160-71

[142] Razumilava N,Smoot RL.Non-canonical Hedgehog signaling contributes to chemotaxis in cholangiocarcinoma.J Hepatol2014;60:599-605 PMCID:PMC3944428

[143] Riedlinger D,Boas-Knoop s.Hedgehog pathway as a potential treatment target in human cholangiocarcinoma.J Hepatobiliary Pancreat Sci2014;21:607-15

[144] Kiesslich T,Wachter J.Activated hedgehog pathway is a potential target for pharmacological intervention in biliary tract cancer.Mol Cell Biochem2014;396:257-68

[145] Anichini G,Stecca B,Raggi C.The role of the hedgehog pathway in cholangiocarcinoma.Cancers2021;13:4774 PMCID:PMC8507550

[146] Thongchot S, Ferraresi A.Cancer-Associated fibroblast-derived il-6 determines unfavorable prognosis in cholangiocarcinoma by affecting autophagy-associated chemoresponse.Cancers2021;13:2134 PMCID:PMC8124468

[147] Nicolás-Boluda A,Laurent G.Photothermal depletion of cancer-associated fibroblasts normalizes tumor stiffness in desmoplastic cholangiocarcinoma.ACS Nano2020;14:5738-53

[148] Cheng K,Zhu J,Liang H.Tumor-associated macrophages in liver cancer: from mechanisms to therapy.Cancer Commun2022;42:1112-40 PMCID:PMC9648394

[149] Dwyer BJ,Gogoi-Tiwari J.TWEAK/Fn14 signalling promotes cholangiocarcinoma niche formation and progression.J Hepatol2021;74:860-72

[150] Yang T,Xu L.Macrophages-aPKC_ɩ-CCL5 feedback loop modulates the progression and chemoresistance in cholangiocarcinoma.J Exp Clin Cancer Res2022;41:23 PMCID:PMC8760815

[151] Diggs LP,Ma C.CD40-mediated immune cell activation enhances response to anti-PD-1 in murine intrahepatic cholangiocarcinoma.J Hepatol2021;74:1145-54 PMCID:PMC9662232

[152] Vaeteewoottacharn K,Pothipan P.Attenuation of CD47-SIRPα signal in cholangiocarcinoma potentiates tumor-associated macrophage-mediated phagocytosis and suppresses intrahepatic metastasis.Transl Oncol2019;12:217-25 PMCID:PMC6231245