Cholangiocarcinoma (CCA) is a highly lethal adenocarcinoma of the hepatobiliary system, which can be classified as intrahepatic, perihilar and distal. Each anatomic subtype has distinct genetic ...aberrations, clinical presentations and therapeutic approaches. In endemic regions, liver fluke infection is associated with CCA, owing to the oncogenic effect of the associated chronic biliary tract inflammation. In other regions, CCA can be associated with chronic biliary tract inflammation owing to choledocholithiasis, cholelithiasis, or primary sclerosing cholangitis, but most CCAs have no identifiable cause. Administration of the anthelmintic drug praziquantel decreases the risk of CCA from liver flukes, but reinfection is common and future vaccination strategies may be more effective. Some patients with CCA are eligible for potentially curative surgical options, such as resection or liver transplantation. Genetic studies have provided new insights into the pathogenesis of CCA, and two aberrations that drive the pathogenesis of non-fluke-associated intrahepatic CCA, fibroblast growth factor receptor 2 fusions and isocitrate dehydrogenase gain-of-function mutations, can be therapeutically targeted. CCA is a highly desmoplastic cancer and targeting the tumour immune microenvironment might be a promising therapeutic approach. CCA remains a highly lethal disease and further scientific and clinical insights are needed to improve patient outcomes.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Intrahepatic cholangiocarcinoma (iCCA) denotes a rare, highly malignant and heterogeneous class of primary liver adenocarcinomas exhibiting phenotypic characteristics of cholangiocyte ...differentiation. Among the distinctive pathological features of iCCA that differentiates the most common macroscopic subtypes (e.g., mass-forming type) of this hepatic tumor from conventional hepatocellular carcinoma, is a prominent desmoplastic reaction manifested as a dense fibro-collagenous enriched tumor stroma. Cancer-associated fibroblasts (CAFs) represent the most abundant mesenchymal cell type in the desmoplastic reaction. While the pro-tumor effects of CAFs in iCCA have been increasingly recognized, more recent cell lineage tracing studies, advanced single cell RNA sequencing, and expanded biomarker analyses have provided new awareness into their ontogeny, as well as underscored their biological complexity as reflected by the presence of multiple subtypes. In addition, evidence has been described to support CAFs potential to display cancer-restrictive roles, including immunosuppression. However, CAFs also play important roles in facilitating metastasis, as exemplified by lymph node metastasis and peritoneal carcinomatosis, which are common in iCCA. Herein, we provide a timely appraisal of the origins and phenotypic and functional complexity of CAFs in iCCA, together with providing mechanistic insights into lymphangiogenesis and peritoneal metastasis relevant to this lethal human cancer.
Cancer-associated fibroblasts (CAF) are abundant in the stroma of desmoplastic cancers where they promote tumor progression. CAFs are "activated" and as such may be uniquely susceptible to apoptosis. ...Using cholangiocarcinoma as a desmoplastic tumor model, we investigated the sensitivity of liver CAFs to the cytotoxic drug navitoclax, a BH3 mimetic. Navitoclax induced apoptosis in CAF and in myofibroblastic human hepatic stellate cells but lacked similar effects in quiescent fibroblasts or cholangiocarcinoma cells. Unlike cholangiocarcinoma cells, neither CAF nor quiescent fibroblasts expressed Mcl-1, a known resistance factor for navitoclax cytotoxicity. Explaining this paradox, we found that mitochondria isolated from CAFs or cells treated with navitoclax both released the apoptogenic factors Smac and cytochrome c, suggesting that they are primed for cell death. Such death priming in CAFs appeared to be due, in part, to upregulation of the proapoptotic protein Bax. Short hairpin RNA-mediated attenuation of Bax repressed navitoclax-mediated mitochondrial dysfunction, release of apoptogenic factors, and apoptotic cell death. In a syngeneic rat model of cholangiocarcinoma, navitoclax treatment triggered CAF apoptosis, diminishing expression of the desmoplastic extracellular matrix protein tenascin C, suppressing tumor outgrowth, and improving host survival. Together, our findings argue that navitoclax may be useful for destroying CAFs in the tumor microenvironment as a general strategy to attack solid tumors.
Intrahepatic cholangiocarcinoma (iCCA), the second most common primary liver cancer, is a highly lethal epithelial cell malignancy exhibiting features of cholangiocyte differentiation. iCCAs can ...potentially develop from multiple cell types of origin within liver, including immature or mature cholangiocytes, hepatic stem cells/progenitor cells, and from transdifferentiation of hepatocytes. Understanding the molecular mechanisms and genetic drivers that diversely drive specific cell lineage pathways leading to iCCA has important biological and clinical implications. In this context, activation of the YAP1-TEAD dependent transcription, driven by Hippo-dependent or -independent diverse mechanisms that lead to the stabilization of YAP1 is crucially important to biliary fate commitment in hepatobiliary cancer. In preclinical models, YAP1 activation in hepatocytes or cholangiocytes is sufficient to drive their malignant transformation into iCCA. Moreover, nuclear YAP1/TAZ is highly prevalent in human iCCA irrespective of the varied etiology, and significantly correlates with poor prognosis in iCCA patients. Based on the ubiquitous expression and diverse physiologic roles for YAP1/TAZ in the liver, recent studies have further revealed distinct functions of active YAP1/TAZ in regulating tumor metabolism, as well as the tumor immune microenvironment. In the current review, we discuss our current understanding of the various roles of the Hippo-YAP1 signaling in iCCA pathogenesis, with a specific focus on the roles played by the Hippo-YAP1 pathway in modulating biliary commitment and oncogenicity, iCCA metabolism, and immune microenvironment. We also discuss the therapeutic potential of targeting the YAP1/TAZ-TEAD transcriptional machinery in iCCA, its current limitations, and what future studies are needed to facilitate clinical translation.
The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is one of the key signaling cascades in cholangiocarcinoma (CCA) cells, mediating their resistance to apoptosis. ...Our aim was to ascertain if sorafenib, a multikinase inhibitor, may also inhibit JAK/STAT signaling and, therefore, be efficacious for CCA. Sorafenib treatment of three human CCA cell lines resulted in Tyr705 phospho‐STAT3 dephosphorylation. Similar results were obtained with the Raf‐kinase inhibitor ZM336372, suggesting sorafenib promotes Tyr705 phospho‐STAT3 dephosphorylation by inhibiting Raf‐kinase activity. Sorafenib treatment enhanced an activating phosphorylation of the phosphatase SHP2. Consistent with this observation, small interfering RNA–mediated knockdown of phosphatase shatterproof 2 (SHP2) inhibited sorafenib‐induced Tyr705 phospho‐STAT3 dephosphorylation. Sorafenib treatment also decreased the expression of Mcl‐1 messenger RNA and protein, a STAT3 transcriptional target, as well as sensitizing CCA cells to tumor necrosis factor–related apoptosis‐inducing ligand (TRAIL)‐mediated apoptosis. In an orthotopic, syngeneic CCA model in rats, sorafenib displayed significant tumor suppression resulting in a survival benefit for treated animals. In this in vivo model, sorafenib also decreased tumor Tyr705 STAT3 phosphorylation and increased tumor cell apoptosis. Conclusion: Sorafenib accelerates STAT3 dephosphorylation by stimulating phosphatase SHP2 activity, sensitizes CCA cells to TRAIL‐mediated apoptosis, and is therapeutic in a syngeneic rat, orthotopic CCA model that mimics human disease. (HEPATOLOGY 2009.)
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Cholangiocarcinoma (CCA) cells paradoxically express the death ligand, tumor necrosis factor–related apoptosis‐inducing ligand (TRAIL) and, therefore, are dependent upon potent survival signals to ...circumvent TRAIL cytotoxicity. CCAs are also highly desmoplastic cancers with a tumor microenvironment rich in myofibroblasts (MFBs). Herein, we examine a role for MFB‐derived CCA survival signals. We employed human KMCH‐1, KMBC, HuCCT‐1, TFK‐1, and Mz‐ChA‐1 CCA cells, as well as human primary hepatic stellate and myofibroblastic LX‐2 cells, for these studies. In vivo experiments were conducted using a syngeneic rat orthotopic CCA model. Coculturing CCA cells with myofibroblastic human primary hepatic stellate cells or LX‐2 cells significantly decreased TRAIL‐induced apoptosis in CCA cells, a cytoprotective effect abrogated by neutralizing platelet‐derived growth factor (PDGF)‐BB antiserum. Cytoprotection by PDGF‐BB was dependent upon Hedgehog (Hh) signaling, because it was abolished by the smoothened (SMO; the transducer of Hh signaling) inhibitor, cyclopamine. PDGF‐BB induced cyclic adenosine monophosphate–dependent protein kinase–dependent trafficking of SMO to the plasma membrane, resulting in glioma‐associated oncogene (GLI)2 nuclear translocation and activation of a consensus GLI reporter gene‐based luciferase assay. A genome‐wide messenger RNA expression analysis identified 67 target genes to be commonly up‐ (50 genes) or down‐regulated (17 genes) by both Sonic hedgehog and PDGF‐BB in a cyclopamine‐dependent manner in CCA cells. Finally, in a rodent CCA in vivo model, cyclopamine administration increased apoptosis in CCA cells, resulting in tumor suppression. Conclusions: MFB‐derived PDGF‐BB protects CCA cells from TRAIL cytotoxicity by a Hh‐signaling–dependent process. These results have therapeutical implications for the treatment of human CCA. (HEPATOLOGY 2011;)
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Periostin is a modular glycoprotein frequently observed to be a major constituent of the extracellular milieu of mass-forming intrahepatic cholangiocarcinoma and other desmoplastic malignant tumors. ...In intrahepatic cholangiocarcinoma, as well as in desmoplastic pancreatic ductal adenocarcinoma, periostin is overexpressed and hypersecreted in large part, if not exclusively, by cancer-associated fibroblasts within the tumor stroma. Through its interaction with specific components of the extracellular tumor matrix, particularly collagen type I and tenascin-C, and with cell surface receptors, notably integrins leading to activation of the Akt and FAK signaling pathways, this TGF-β family-inducible matricellular protein appears to be functioning as a key extracellular matrix molecule regulating such critically important and diverse malignant tumor behaviors as tumor fibrogenesis and desmoplasia, invasive malignant cell growth, chemoresistance, and metastatic colonization. This review will discuss current evidence and basic molecular mechanisms implicating periostin as a mediator of intrahepatic cholangiocarcinoma invasive growth. In addition, its significance as a potential prognostic biomarker for intrahepatic cholangiocarcinoma patients, as well as future possibilities and challenges as a molecular target for cholangiocarcinoma therapy and/or prevention, will be critically evaluated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
PURPOSE OF REVIEWThe aim of this brief review is to provide an up-to-date view of the role played by α-smooth muscle actin-positive cancer-associated fibroblastic cells in promoting intrahepatic ...cholangiocarcinoma progression.
RECENT FINDINGSAn increase in α-smooth muscle actin-positive cancer-associated fibroblastic cells in the stroma of intrahepatic cholangiocarcinoma has recently been demonstrated to accelerate cholangiocarcinoma progression. However, our understanding of the evolving cellular and molecular interactions between these stromal cells and cholangiocarcinoma cells in relation to promoting intrahepatic cholangiocarcinoma progression is only just beginning to be elucidated. Imbalances in multifactorial growth factor/cytokine signaling, activation of Hedgehog-GLI signaling and of proteases involved in extracellular matrix remodeling, and matricellular protein–protein and protein–cholangiocarcinoma cell interactions, as well as hypoxia, all appear to factor into the complex and dynamic interactive mechanisms through which cancer-associated fibroblastic cells crosstalk with cholangiocarcinoma cells to promote intrahepatic cholangiocarcinoma progression. Novel three-dimensional organotypic co-culture models are being developed to facilitate relevant studies of cancer-associated fibroblastic cell/cholangiocarcinoma cell interactions that may more accurately mimic physiologically pertinent features of the tumor.
SUMMARYIncreasing our understanding of critical interactive pathways by which cancer-associated fibroblastic cells crosstalk with cholangiocarcinoma cells to promote tumor progression can lead to the development of novel multitargeting strategies for intrahepatic cholangiocarcinoma therapy.
Aim: Recent studies have suggested that increased α‐smooth muscle‐actin positive myofibroblastic cells (α‐SMA positive CAF) in the desmoplastic stroma may relate to a more aggressive cancer and ...worse survival outcomes for intrahepatic cholangiocarcinoma (ICC) patients. To facilitate investigating cellular and molecular interactions between α‐SMA positive CAF and cholangiocarcinoma cells related to ICC progression, we developed a novel 3‐D organotypic culture model of cholangiocarcinoma that more accurately mimics the stromal microenvironment, gene expression profile and select pathophysiological characteristics of desmoplastic ICC in vivo.
Methods: This unique model was established by co‐culturing within a type I collagen gel matrix, a strain of cholangiocarcinoma cells (derived from an ICC formed in syngeneic rat liver following bile duct inoculation of spontaneously‐transformed rat cholangiocytes) with varying numbers of clonal α‐SMA positive CAF established from the same tumor type.
Results: Cholangiocarcinoma cells and α‐SMA positive CAF in monoculture each exhibited cell‐specific biomarker gene expression profiles characteristic of stromal myofibroblastic cell versus malignant cholangiocyte cell types. In comparison, the gene expression profile and histopathological characteristics exhibited by the organotypic co‐culture closely resembled those of whole tissue samples of the parent orthotopic ICC. We further showed α‐SMA positive CAF to significantly enhance cholangiocarcinoma cell “ductal‐like” growth and cancer cell migration/invasiveness in vitro, as well as to promote upregulated expression of select genes known to be associated with ICC invasion.
Conclusion: This novel organotypic model provides an important new resource for studying the effects of microenvironment on cholangiocarcinoma progression in vitro and may have potential as a preclinical model for identifying molecularly targeted therapies.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK