Establishment and characterisation of six human biliary tract cancer cell lines

Establishment and characterization of DPC-X4: a novel mixed-type ampullary cancer cell line

Mixed-type ampullary cancer is a distinct subtype of ampullary cancer that manifests a merging of the biological characteristics of both intestinal and pancreaticobiliary subtypes. The absence of established cell lines specific to this subtype has resulted in a concomitant scarcity of research on its tumorigenic mechanisms and the development of novel therapeutic modalities. The present study achieved the successful establishment of a novel mixed-type ampullary cancer cell line, designated DPC-X4 through primary culture techniques. Subsequent analyses pertaining to phenotypic characteristics, molecular profiling, biomarker identification, and histological features validated the DPC-X4 cell line as a potent model for delineating the pathogenesis of mixed-type ampullary cancer and facilitating the development of new pharmacological agents. This newly established cell line was subjected to continuous cultivation for 1 year, with stable passaging for over 50 generations. Notably, the DPC-X4 cell line manifested typical morphological features associated with epithelial tumors. Furthermore, the population doubling time for the DPC-X4 cell line was determined at 70 h. Short tandem repeat (STR) analysis confirmed that the DPC-X4 cell line exhibited a high genetic concordance with the primary tumor from the patient. Karyotypic profiling indicated an abnormal sub-triploid karyotype, with representative karyotypes of 57, XXY inv (9), 14p + , 15p + , der (17), + mar. The DPC-X4 cell line demonstrated a high capacity for efficient organoid formation under suspension culture conditions. In addition, the subcutaneous inoculation of DPC-X4 cells into NXG mice led to the formation of xenografted tumors. The results of drug sensitivity testing indicated that DPC-X4 cells were sensitive to paclitaxel and resistant to oxaliplatin, 5-fluorouracil, and gemcitabine. Immunohistochemistry revealed positive expression of CK7, CK19, and CK20 in DPC-X4 cells, while CDX2 demonstrated negative expression. In addition, positive expression of E-cadherin and vimentin was identified in DPC-X4 cells, with a proliferation index indicated by Ki-67 at 70%. The findings of our study establish DPC-X4 as a novel mixed-type ampullary cancer cell line, which can serve as a potential experimental model for exploring the pathogenesis of ampullary cancer and the development of therapeutic drugs.

Establishment and characterization of a new human ampullary carcinoma cell line, DPC-X1

BACKGROUND

An in-depth study of the pathogenesis and biological characteristics of ampullary carcinoma is necessary to identify appropriate treatment strategies. To date, only eight ampullary cancer cell lines have been reported, and a mixed-type ampullary carcinoma cell line has not yet been reported.

AIM

To establish a stable mixed-type ampullary carcinoma cell line originating from Chinese.

METHODS

Fresh ampullary cancer tissue samples were used for primary culture and subculture. The cell line was evaluated by cell proliferation assays, clonal formation assays, karyotype analysis, short tandem repeat (STR) analysis and transmission electron microscopy. Drug resistances against oxaliplatin, paclitaxel, gemcitabine and 5-FU were evaluated by cell counting kit-8 assay. Subcutaneous injection 1 × 10⁶ cells to three BALB/c nude mice for xenograft studies. The hematoxylin-eosin staining was used to detect the pathological status of the cell line. The expression of biomarkers cytokeratin 7 (CK7), cytokeratin 20 (CK20), cytokeratin low molecular weight (CKL), Ki67 and carcinoembryonic antigen (CEA) were determined by immunocytochemistry assay.

RESULTS

DPC-X1 was continuously cultivated for over a year and stably passaged for more than 80 generations; its population doubling time was 48 h. STR analysis demonstrated that the characteristics of DPC-X1 were highly consistent with those of the patient’s primary tumor. Furthermore, karyotype analysis revealed its abnormal sub-tetraploid karyotype. DPC-X1 could efficiently form organoids in suspension culture. Under the transmission electron microscope, microvilli and pseudopods were observed on the cell surface, and desmosomes were visible between the cells. DPC-X1 cells inoculated into BALB/C nude mice quickly formed transplanted tumors, with a tumor formation rate of 100%. Their pathological characteristics were similar to those of the primary tumor. Moreover, DPC-X1 was sensitive to oxaliplatin and paclitaxel and resistant to gemcitabine and 5-FU. Immunohistochemistry showed that the DPC-X1 cells were strongly positive for CK7, CK20, and CKL; the Ki67 was 50%, and CEA was focally expressed.

CONCLUSION

Here, we have constructed a mixed-type ampullary carcinoma cell line that can be used as an effective model for studying the pathogenesis of ampullary carcinoma and drug development.

Criteria for preclinical models of cholangiocarcinoma: scientific and medical relevance

Cholangiocarcinoma (CCA) is a rare malignancy that develops at any point along the biliary tree. CCA has a poor prognosis, its clinical management remains challenging, and effective treatments are lacking. Therefore, preclinical research is of pivotal importance and necessary to acquire a deeper understanding of CCA and improve therapeutic outcomes. Preclinical research involves developing and managing complementary experimental models, from in vitro assays using primary cells or cell lines cultured in 2D or 3D to in vivo models with engrafted material, chemically induced CCA or genetically engineered models. All are valuable tools with well-defined advantages and limitations. The choice of a preclinical model is guided by the question(s) to be addressed; ideally, results should be recapitulated in independent approaches. In this Consensus Statement, a task force of 45 experts in CCA molecular and cellular biology and clinicians, including pathologists, from ten countries provides recommendations on the minimal criteria for preclinical models to provide a uniform approach. These recommendations are based on two rounds of questionnaires completed by 35 (first round) and 45 (second round) experts to reach a consensus with 13 statements. An agreement was defined when at least 90% of the participants voting anonymously agreed with a statement. The ultimate goal was to transfer basic laboratory research to the clinics through increased disease understanding and to develop clinical biomarkers and innovative therapies for patients with CCA.

Establishing Patient-Derived Cancer Cell Cultures and Xenografts in Biliary Tract Cancer

PURPOSE

Biliary tract cancers (BTCs) are rare and show a dismal prognosis with limited treatment options. To improve our understanding of these heterogeneous tumors and develop effective therapeutic agents, suitable preclinical models reflecting diverse tumor characteristics are needed. We established and characterized new patient-derived cancer cell cultures and patient-derived xenograft (PDX) models using malignant ascites from five patients with BTC.

MATERIALS AND METHODS

Five patient-derived cancer cell cultures and three PDX models derived from malignant ascites of five patients with BTC, AMCBTC-01, -02, -03, -04, and -05, were established. To characterize the models histogenetically and confirm whether characteristics of the primary tumor were maintained, targeted sequencing and histopathological comparison between primary tissue and xenograft tumors were performed.

RESULTS

From malignant ascites of five BTC patients, five patient-derived cancer cell cultures (100% success rate), and three PDXs (60% success rate) were established. The morphological characteristics of three primary xenograft tumors were compared with those of matched primary tumors, and they displayed a similar morphology. The mutated genes in samples (models, primary tumor tissue, or both) from more than one patient were TP53 (n=2), KRAS (n=2), and STK11 (n=2). Overall, the pattern of commonly mutated genes in BTC cell cultures was different from that in commercially available BTC cell lines.

CONCLUSION

We successfully established the patient-derived cancer cell cultures and xenograft models derived from malignant ascites in BTC patients. These models accompanied by different genetic characteristics from commercially available models will help better understand BTC biology.

Molecular pathways in periampullary cancer: An overview

Molecular alterations in oncogenes and tumor suppressors in various signaling pathways are basis for personalized therapy in cancer. Periampullary carcinoma behaves differently from pancreatic carcinoma both in prognosis and outcome, therefore it needs special attention. Pancreatic cancer have higher incidence of nodal spread and perineural &lymphovascular invasion suggesting it biologically more aggressive tumor compared to periampullary cancer. Since PAC tumors consist of heterogenous tissue of origin, they might contain different mutations in tumor associated genes and other changes in tissue composition among different subgroups clubbed together. Significant progress has been made in understanding the molecular nature of PAC in the previous two decades, and a large number of mutations and other genetic changes have been identified as being responsible for the disease. This review article targets to collate and discuss the molecular evolution of PAC and their implication in its outcome. As per literature, mitogen-activated protein kinase (MAPK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), and Wnt signaling are the most common pathways involved in PAC. Mutations in KRAS, TP53, CTNNB1, SMAD4 and APC genes were the most frequently reported. I-subtype resembles colorectal cancer while the morphology of PB-type shows close resemblance to pancreatic tumors. The frequency of driver gene mutations is higher in I-type compared to PB-type of PAC indicating I-type to be genetically more unstable. The genetic landscape of PAC obtained from WES data highlighted PI3/AKT pathway to be a primary target in I-type and RAS/RAF in PB-type.

Establishment and Characterization of a New Human Intrahepatic Cholangiocarcinoma Cell Line LIV27

Cholangiocarcinoma (CCA) is a highly lethal cancer arising from the biliary tract epithelium. The cancer biology of this neoplasm is not well understood. To date, only a few CCA cell lines have been reported, which were mostly developed from Asian patients. In this study, we report and characterize a new intrahepatic CCA cell line, LIV27, derived from a surgically resected tumor in a 67-year-old Caucasian woman with primary sclerosing cholangitis (PSC). LIV27 cells grow well in collagen-coated flasks or plates with a doubling time of 57.8 h at passage 14. LIV27 cells have high tumorigenicity in nude mice and stain positive for CK7 and CK19, markers that differentiate CCA from hepatocellular carcinoma. Karyotype analysis showed that LIV27 is aneuploid. We established a single-locus short tandem repeat profile for the LIV27 cell line. This newly established cell line will be a useful model for studying the molecular pathogenesis of, and developing novel therapies for, cholangiocarcinoma.

Development and Characterization of Human Primary Cholangiocarcinoma Cell Lines

Cholangiocarcinoma (CCA) is the second most common primary liver tumor and is associated with late diagnosis, limited treatment options, and a 5-year survival rate of around 30%. CCA cell lines were first established in 1971, and since then, only 70 to 80 CCA cell lines have been established. These cell lines have been essential in basic and translational research to understand and identify novel mechanistic pathways, biomarkers, and disease-specific genes. Each CCA cell line has unique characteristics, reflecting a specific genotype, sex-related properties, and patient-related signatures, making them scientifically and commercially valuable. CCA cell lines are crucial in the use of novel technologies, such as three-dimensional organoid models, which help to model the tumor microenvironment and cell-to-cell crosstalk between tumor-neighboring cells. This review highlights crucial information on CCA cell lines, including: i) type of CCA (eg, intra- or extrahepatic), ii) isolation source (eg, primary tumor or xenograft), iii) chemical digestion method (eg, trypsin or collagenase), iv) cell-sorting method (colony isolation or removal of fibroblasts), v) maintenance-medium choice (eg, RPMI or Dulbecco's modified Eagle's medium), vi) cell morphology (eg, spindle or polygonal shape), and vii) doubling time of cells.

Ursodeoxycholic acid shows antineoplastic effects in bile duct cancer cells via apoptosis induction; p53 activation; and EGFR-ERK, COX-2, and PI3K-AKT pathway inhibition

Unlike in normal cells, ursodeoxycholic acid (UDCA) causes apoptosis rather than protection in cancer cells. Aim of this study was to demonstrate whether UDCA actually inhibits proliferation and induces apoptosis in bile duct cancer cells; the effect of UDCA on the expression of COX-2, PI3K/AKT, ERK, and EGFR; how UDCA affects cancer cell invasiveness and metastasis, since these effects are not established in bile duct cancer cells. SNU-245 cells (human extrahepatic bile duct cancer cells) were cultured. MTT assays were performed to evaluate the effect of UDCA on the cell proliferation. A cell death detection enzyme-linked immunosorbent assay and a caspase-3 activity assay were used to determine apoptosis. Western blot analysis measured expression levels of various proteins. The invasiveness of the cancer cells was evaluated by invasion assay. In cultured bile duct cancer cells, UDCA suppressed cell proliferation in bile duct cancer cells by inducing apoptosis and p53 activation, blocking deoxycholic acid (DCA)-induced activated EGFR-ERK signaling and COX-2, inhibiting DCA-induced activated PI3K-AKT signaling, and suppressing the invasiveness of bile duct cancer cells. In addition, a MEK inhibitor impaired UDCA-induced apoptosis in bile duct cancer cells. UDCA has antineoplastic and apoptotic effects in bile duct cancer cells. Thus, UDCA could be a chemopreventive agent in patients with a high risk of cancer, and/or a therapeutic option that enhances other chemotherapeutics.

Patient-Derived Organoids of Cholangiocarcinoma

Cholangiocarcinoma (CC) is an aggressive malignancy with an inferior prognosis due to limited systemic treatment options. As preclinical models such as CC cell lines are extremely rare, this manuscript reports a protocol of cholangiocarcinoma patient-derived organoid culture as well as a protocol for the transition of 3D organoid lines to 2D cell lines. Tissue samples of non-cancer bile duct and cholangiocarcinoma were obtained during surgical resection. Organoid lines were generated following a standardized protocol. 2D cell lines were generated from established organoid lines following a novel protocol. Subcutaneous and orthotopic patient-derived xenografts were generated from CC organoid lines, histologically examined, and treated using standard CC protocols. Therapeutic responses of organoids and 2D cell lines were examined using standard CC agents. Next-generation exome and RNA sequencing was performed on primary tumors and CC organoid lines. Patient-derived organoids closely recapitulated the original features of the primary tumors on multiple levels. Treatment experiments demonstrated that patient-derived organoids of cholangiocarcinoma and organoid-derived xenografts can be used for the evaluation of novel treatments and may therefore be used in personalized oncology approaches. In summary, this study establishes cholangiocarcinoma organoids and organoid-derived cell lines, thus expanding translational research resources of cholangiocarcinoma.

Evolution of the Experimental Models of Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare, aggressive disease with poor overall survival. In advanced cases, surgery is often not possible or fails; in addition, there is a lack of effective and specific therapies. Multidisciplinary approaches and advanced technologies have improved the knowledge of CCA molecular pathogenesis, highlighting its extreme heterogeneity and high frequency of genetic and molecular aberrations. Effective preclinical models, therefore, should be based on a comparable level of complexity. In the past years, there has been a consistent increase in the number of available CCA models. The exploitation of even more complex CCA models is rising. Examples are the use of CRISPR/Cas9 or stabilized organoids for in vitro studies, as well as patient-derived xenografts or transgenic mouse models for in vivo applications. Here, we examine the available preclinical CCA models exploited to investigate: (i) carcinogenesis processes from initiation to progression; and (ii) tools for personalized therapy and innovative therapeutic approaches, including chemotherapy and immune/targeted therapies. For each model, we describe the potential applications, highlighting both its advantages and limits.

Cell Model Passports-a hub for clinical, genetic and functional datasets of preclinical cancer models

In vitro cancer cell cultures are facile experimental models used widely for research and drug development. Many cancer cell lines are available and efforts are ongoing to derive new models representing the histopathological and molecular diversity of tumours. Cell models have been generated by multiple laboratories over decades and consequently their annotation is incomplete and inconsistent. Furthermore, the relationships between many patient-matched and derivative cell lines have been lost, and accessing information and datasets is time-consuming and difficult. Here, we describe the Cell Model Passports database; cellmodelpassports.sanger.ac.uk, which provides details of cell model relationships, patient and clinical information, as well as access to associated genetic and functional datasets. The Passports database currently contains curated details and standardized annotation for >1200 cell models, including cancer organoid cultures. The Passports will be updated with newly derived cell models and datasets as they are generated. Users can navigate the database via tissue, cancer-type, genetic feature and data availability to select a model most suitable for specific applications. A flexible REST-API provides programmatic data access and exploration. The Cell Model Passports are a valuable tool enabling access to high-dimensional genomic and phenotypic cancer cell model datasets empowering diverse research applications.

Functional and genomic characterization of three novel cell lines derived from a metastatic gallbladder cancer tumor

Background

Gallbladder cancer (GBC) is the most common tumor of the biliary tract. The incidence of GBC shows a large geographic variability, being particularly frequent in Native American populations. In Chile, GBC represents the second cause of cancer-related death among women. We describe here the establishment of three novel cell lines derived from the ascitic fluid of a Chilean GBC patient, who presented 46% European, 36% Mapuche, 12% Aymara and 6% African ancestry.

Results

After immunocytochemical staining of the primary cell culture, we isolated and comprehensively characterized three independent clones (PUC-GBC1, PUC-GBC2 and PUC-GBC3) by short tandem repeat DNA profiling and RNA sequencing as well as karyotype, doubling time, chemosensitivity, in vitro migration capability and in vivo tumorigenicity assay. Primary culture cells showed high expression of CK7, CK19, CA 19-9, MUC1 and MUC16, and negative expression of mesothelial markers. The three isolated clones displayed an epithelial phenotype and an abnormal structure and number of chromosomes. RNA sequencing confirmed the increased expression of cytokeratin and mucin genes, and also of TP53 and ERBB2 with some differences among the three cells lines, and revealed a novel exonic mutation in NF1. The PUC-GBC3 clone was the most aggressive according to histopathological features and the tumorigenic capacity in NSG mice.

Conclusions

The first cell lines established from a Chilean GBC patient represent a new model for studying GBC in patients of Native American descent.

Genomic Profiling of Biliary Tract Cancer Cell Lines Reveals Molecular Subtypes and Actionable Drug Targets

Biliary tract cancers (BTCs) currently have no approved targeted therapies. Although genomic profiling of primary BTCs has identified multiple potential drug targets, accurate models are needed for their evaluation. Genomic profiling of 22 BTC cell lines revealed they harbor similar mutational signatures, recurrently mutated genes, and genomic alterations to primary tumors. Transcriptomic profiling identified two major subtypes, enriched for epithelial and mesenchymal genes, which were also evident in patient-derived organoids and primary tumors. Interrogating these models revealed multiple mechanisms of MAPK signaling activation in BTC, including co-occurrence of low-activity BRAF and MEK mutations with receptor tyrosine kinase overexpression. Finally, BTC cell lines with altered ERBB2 or FGFRs were exquisitely sensitive to specific targeted agents, whereas surprisingly, IDH1-mutant lines did not respond to IDH1 inhibitors in vitro. These findings establish BTC cell lines as robust models of primary disease, reveal specific molecular disease subsets, and highlight specific molecular vulnerabilities in these cancers.

•

BTC cell lines harbor similar genomic alterations to primary tumors

•

Transcriptomic profiling of BTC cell lines identified two molecular subtypes

•

MAPK signaling is activated in BTC via multiple mechanisms

•

BTC lines with deregulated ERBB2 or FGFRs respond to specific targeted therapies

Establishment and Characterization of Two Novel Cholangiocarcinoma Cell Lines

Background

Cholangiocarcinoma (CCA) is a rare, aggressive and highly lethal tumor. The disease is very difficult to diagnose and multi-modality treatments are ineffective. To improve our understanding of the biological characteristics of CCA, and facilitate the identification of valid treatments, an in-depth characterization of two novel Chinese patient-derived primary CCA cell lines was performed.

Methods

Two CCA cell lines were developed and labelled ZJU-0826 and -1125. The two cell lines were characterized with respect to phenotypic, molecular, biomarker, functional and histological properties.

Results

Two novel cell lines were cultured for 2 years, and maintained for more than 100 passages. They retained their typical biliary epithelial morphology and ultrastructure. The population doubling times of ZJU-0826, and -1125 were 63.84 h and 44.73 h, respectively. The cells exhibited near-triploid karyotypes with complex structural aberrations. ZJU-1125 cells had mutations in TP53 exons. Short tandem repeats genotyping confirmed the human origin and difference between lines. An immunophenotype analysis showed that ZJU-0826 is positive for CD44, CD29, Pdx1, CD236, FoxA1, FoxA2, and Nanog, and ZJU-1125 positive for CD44, CD29, CD133, Pdx1, FoxA1, FoxA2, and Nanog. ZJU-1125 had greater invasion ability in vitro and tumorigenicity than those of ZJU-0826.

Conclusions

Our results confirm the validity of the ZJU-0826 and -1125 as representative models for the elucidation of the molecular pathogenesis of perihilar CCA, and intrahepatic CCA in both in vitro and in vivo studies, respectively.

Electronic supplementary material

The online version of this article (10.1245/s10434-019-07649-5) contains supplementary material, which is available to authorized users.

Characteristics of a novel cell line ZJU-0430 established from human gallbladder carcinoma

Background

Gallbladder cancer is the most common malignant neoplasm of the biliary tract, responsible for 80–95% of cases. Appropriate models are required for investigating the molecular pathogenesis of gallbladder cancer.

Methods

In this study, we aimed to establish a gallbladder cancer cell line from primary tumour. Single cell RNA sequencing, Light and electron microscopy, DNA content analysis, cytogenetic analysis, short tandem repeat (STR) DNA fingerprint analysis, immunophenotypic characterization, and xeno-transplantation were utilized to characterize the novel ZJU-0430 cell line in vitro and in vivo.

Results

The cell line showed multiple cell shapes and characteristic epithelial morphologies under the microscope, but no too much heterogeneity by scRNA-Seq, with a population doubling time (PDT) of 19.81 h, which was shorter than that for GBC-SD cells. An immunophenotypic analysis revealed that ZJU-0430 cells were positive for CD24, CD44, CD29 and CD133 expression, and partially positive for CD184, and CD326 expression, and negative for CD34, CD90, CD117, and CD338 expression, similar to the primary cancer cells. A pathological analysis confirmed the origination of cell line from gallbladder tumour. ZJU-0430 cells had higher migration, invasion and proliferation properties than GBC-SD cells in vitro, and showed in vivo tumorigenicity in nude mouse xenograft settings.

Conclusions

The results confirm the potential utility of ZJU-0430 cell line as a representative model of gallbladder cancer and suggest that it could be used in the in vitro and in vivo studies of gallbladder cancer pathogenesis and to develop new therapeutics.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0911-1) contains supplementary material, which is available to authorized users.

Establishment of Highly Transplantable Cholangiocarcinoma Cell Lines from a Patient-Derived Xenograft Mouse Model

Cholangiocarcinoma (CCA) is a deadly malignant tumor of the liver. It is a significant health problem in Thailand. The critical obstacles of CCA diagnosis and treatment are the high heterogeneity of disease and considerable resistance to treatment. Recent multi-omics studies revealed the promising targets for CCA treatment; however, limited models for drug discovery are available. This study aimed to develop a patient-derived xenograft (PDX) model as well as PDX-derived cell lines of CCA for future drug screening. From a total of 16 CCA frozen tissues, 75% (eight intrahepatic and four extrahepatic subtypes) were successfully grown and subpassaged in Balb/c Rag-2-/-/Jak3-/- mice. A shorter duration of PDX growth was observed during F0 to F2 transplantation; concomitantly, increased Oct-3/4 and Sox2 were evidenced in 50% and 33%, respectively, of serial PDXs. Only four cell lines were established. The cell lines exhibited either bile duct (KKK-D049 and KKK-D068) or combined hepatobiliary origin (KKK-D131 and KKK-D138). These cell lines acquired high transplantation efficiency in both subcutaneous (100%) and intrasplenic (88%) transplantation models. The subcutaneously transplanted xenograft retained the histological architecture as in the patient tissues. Our models of CCA PDX and PDX-derived cell lines would be a useful platform for CCA precision medicine.

Metformin Induces Apoptosis and Inhibits Proliferation through the AMP-Activated Protein Kinase and Insulin-like Growth Factor 1 Receptor Pathways in the Bile Duct Cancer Cells

Background/Aims: Metformin has been found to have antineoplastic activity in some cancer cells. This study was performed to determine whether metformin inhibits the proliferation of bile duct cancer cells by inducing apoptosis and its effects on the expression of gene-related proteins involved in cancer growth.

Methods: Human extrahepatic bile duct cancer cells (SNU-245 and SNU-1196) were cultured. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays were performed to determine the effect of metformin on the cell proliferation. Apoptosis was measured by a cell death detection enzyme-linked immunosorbent assay and a caspase-3 activity assay. Expression levels of various proteins, with or without specific small interfering ribonucleic acid-induced gene disruption, were measured by Western blot analysis. The migratory activity of the cancer cells was evaluated by wound healing assay.

Results: Metformin suppressed cell proliferation in bile duct cancer cells by inducing apoptosis. Metformin inhibited mammalian target of rapamycin (mTOR) by activation of tuberous sclerosis complex 2 (TSC-2) through phosphorylation of adenosine monophosphate-activated protein kinase at threonine-172 (AMPK^Thr172). Hyperglycemia impaired metformin-induced AMPK^Thr172 activation and enhanced phosphorylation of AMPK at serine-485 (AMPK^Ser485). Metformin blocked the inhibitory effect of insulin-like growth factor 1 receptor (IGF-1R)/insulin receptor substrate 1 (IRS-1) pathway on TSC-2, and hyperglycemia impaired metformin-induced inhibition of IGF-1R/IRS-1 pathway and modulated the invasiveness of bile duct cancer cells; however, this effect was impaired by hyperglycemia.

Conclusions: Metformin has antineoplastic effects in bile duct cancer, and hyperglycemic environment interrupts the effect of metformin. In addition, AMPK and IGF-1R play a key role in the proliferation of bile duct cancer cells.

EF24 Suppresses Cholangiocellular Carcinoma Progression, Inhibits STAT3 Phosphorylation, and Induces Apoptosis via ROS-Mediated Oxidative Stress

Therapeutic options for advanced stage cholangiocellular carcinoma (CCC) are very limited as of today and patients carry an exceptionally poor overall prognosis. In recent years, increasing evidence has been accumulated to suggest that malignant cells widely show increased intrinsic ROS levels and exhibit altered redox profiles as compared to normal counterparts, opening up potential avenues for therapeutic intervention. This study provides preclinical experimental evidence of therapeutic activity of the curcumin analog EF24 in cholangiocarcinoma models. In CCC cell lines, EF24 inhibited cell viability and induced apoptosis through excessive ROS generation. Moreover, administration of EF24 led to depletion of total intracellular GSH levels, induced mitochondrial depolarization, and abrogated STAT3 phosphorylation. Of interest, these effects were readily averted by treating the cells with exogenous antioxidants such as N-acetyl cysteine (NAC) or glutathione monoethyl ester (GEE). In vivo, EF24, solubilized using a cyclodextrin formulation, significantly suppressed the growth of tumor xenografts without exhibiting any toxic adverse effects. Immunohistochemical analysis of extracted tumor tissues demonstrated reduced nuclear staining for Ki-67 and downregulation of phospho-STAT3 as well as strong staining for oxidative stress biomarker 8-OHdG. Therefore, the data presented here suggest EF24 as potential therapeutic compound against CCC which might act at least to some extent through ROS-induced oxidative damage, subsequently inducing apoptosis. Further evaluation of this approach should be carried out in future follow-up studies.

Jab1 Silencing Inhibits Proliferation and Sensitizes to Cisplatin in Biliary Tract Cancer

Purpose

Jab1 is a coactivator of c-Jun that enhances the transcriptional function of c-Jun. Jab1 is frequently overexpressed in various cancers and is associatedwith poor prognosis of cancer patients. Thus, Jab1 could be a potential therapeutic target in cancer. However, the role of Jab1 in biliary tract cancer (BTC) has not been studied.

Materials and Methods

We performed in vitro and in vivo experiments to evaluate the therapeutic potential ofJab1 inhibition in BTC.

Results

Among 8 BTC cell lines, many showed higher Jab1 expression levels. In addition, Jab1 silencing by siRNA increased p27 expression levels. SNU478 and HuCCT-1 cells exhibited profound Jab1 knockdown and increased p27 expression by Jab1-specific siRNA transfection. Jab1 silencing induced anti-proliferative and anti-migratory effects and resulted in G1 cell cycle arrest in SNU478 and HuCCT-1 cells. In addition, Jab1 silencing potentiated the anti-proliferative and anti-migratory effects of cisplatin by increasing DNA damage. Interestingly,Jab1 knockdown increased PTEN protein half-life, resulting in increased PTEN expression. In the HuCCT-1 mouse xenograft model, stable knockdown of Jab1 by shRNA also showed anti-proliferative effects in vivo, with decreased Ki-67 expression and AKT phosphorylation and increased Terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling and p27 expression.

Conclusion

Jab1 knockdown demonstrated anti-proliferative and anti-migratory effects in BTC cells by increasing DNA damage and stabilizing PTEN, resulting in G1 cell cycle arrest. In addition, Jab1 silencing potentiated the anti-proliferative effects of cisplatin. Our data suggest that Jab1 may be a potential therapeutic target in BTC that is worthy of further investigations.

Discovery of glycocholic acid and taurochenodeoxycholic acid as phenotypic biomarkers in cholangiocarcinoma

Although several biomarkers can be used to distinguish cholangiocarcinoma (CCA) from healthy controls, differentiating the disease from benign biliary disease (BBD) or pancreatic cancer (PC) is a challenge. CCA biomarkers are associated with low specificity or have not been validated in relation to the biological effects of CCA. In this study, we quantitatively analyzed 15 biliary bile acids in CCA (n = 30), BBD (n = 57) and PC (n = 17) patients and discovered glycocholic acid (GCA) and taurochenodeoxycholic acid (TCDCA) as specific CCA biomarkers. Firstly, we showed that the average concentration of total biliary bile acids in CCA patients was quantitatively less than in other patient groups. In addition, the average composition ratio of primary bile acids and conjugated bile acids in CCA patients was the highest in all patient groups. The average composition ratio of GCA (35.6%) in CCA patients was significantly higher than in other patient groups. Conversely, the average composition ratio of TCDCA (13.8%) in CCA patients was significantly lower in all patient groups. To verify the biological effects of GCA and TCDCA, we analyzed the gene expression of bile acid receptors associated with the development of CCA in a CCA cell line. The gene expression of transmembrane G protein coupled receptor (TGR5) and sphingosine 1-phosphate receptor 2 (S1PR2) in CCA cells treated with GCA was 8.6-fold and 3.4-fold higher compared with control (untreated with bile acids), respectively. Gene expression of TGR5 and S1PR2 in TCDCA-treated cells was not significantly different from the control. Taken together, our study identified GCA and TCDCA as phenotype-specific biomarkers for CCA.

Ampullary carcinoma-A genetic perspective

Ampulla of vater carcinoma (AVC) is a rare gastrointestinal tumour that is associated with a high mortality rate and it's often diagnosed at later stages due to lack of clinical symptoms. Early diagnosis of this condition is essential to effectively treat patients for better prognosis. A significant amount of advancement has been made in understanding the molecular nature of cancer in the past decade. A substantial number of mutations and alterations have been detected in various tumors. Despite the occurrence of AVC across the globe, the number of studies conducted on this tumor type remains low; this is largely due to its rare occurrence. Moreover, AVC tissues are complex and contain mutations in oncogenes, tumour suppressors, apoptotic proteins, cell proliferation proteins, cell signaling proteins, transcription factors, chromosomal abnormalities and cellular adhesion proteins. The frequently mutated genes included KRAS, TP53 and SMAD4 and are associated with prognosis. Several molecules of the PI3K, Wnt signaling, TGF-beta pathway and cell cycle have also been altered in AVCs. This review comprises of all the genetic mutations, associated pathways and related prognosis that are involved in AVCs from the year 1989 to 2017. This report can be used as a stepping-stone to establish biomarkers for early diagnosis of AVC and to discover molecular targets for drug therapy.

Therapeutic implication of HER2 in advanced biliary tract cancer

Currently, there is no validated therapeutic target for biliary tract cancer (BTC). This study aimed to investigate the pre-clinical and clinical implication of HER2 as a therapeutic target in BTC. We established two novel HER2-amplified BTC cell lines, SNU-2670 and SNU-2773, from gallbladder cancer patients. SNU-2670 and SNU-2773 cells were sensitive to trastuzumab, dacomitinib, and afatinib compared with nine HER2-negative BTC cell lines. Dacomitinib and afatinib led to G1 cell cycle arrest in SNU-2773 cells and apoptosis in SNU-2670 cells. Furthermore, dacomitinib, afatinib, and trastuzumab showed synergistic cytotoxicity when combined with some cytotoxic drugs including gemcitabine, cisplatin, paclitaxel, and 5-fluorouracil. In a SNU-2670 mouse xenograft model, trastuzumab demonstrated a good anti-tumor effect as a monotherapy and in combination with gemcitabine increasing apoptosis. In our clinical data, 13.0% of patients with advanced BTC were defined as HER2-positive. Of these, three patients completed HER2-targeted chemotherapy. Two of them demonstrated a partial response, and the other one showed stable disease for 18 weeks. In summary, these pre-clinical and clinical data suggest that HER2 could be a therapeutic target, and that a HER2-targeting strategy should be developed further in patients with HER2-positive advanced BTC.

Emergence of Intrahepatic Cholangiocarcinoma: How High-Throughput Technologies Expedite the Solutions for a Rare Cancer Type

Intrahepatic cholangiocarcinoma (ICC) is the cancer of the intrahepatic bile ducts, and together with hepatocellular carcinoma (HCC), constitute the majority of primary liver cancers. ICC is a rare disorder as its overall incidence is < 1/100,000 in the United States and Europe. However, it shows much higher incidence in particular geographical regions, such as northeastern Thailand, where liver fluke infection is the most common risk factor of ICC. Since the early stages of ICC are often asymptomatic, the patients are usually diagnosed at advanced stages with no effective treatments available, leading to the high mortality rate. In addition, unclear genetic mechanisms, heterogeneous nature, and various etiologies complicate the development of new efficient treatments. Recently, a number of studies have employed high-throughput approaches, including next-generation sequencing and mass spectrometry, in order to understand ICC in different biological aspects. In general, the majority of recurrent genetic alterations identified in ICC are enriched in known tumor suppressor genes and oncogenes, such as mutations in TP53, KRAS, BAP1, ARID1A, IDH1, IDH2, and novel FGFR2 fusion genes. Yet, there are no major driver genes with immediate clinical solutions characterized. Interestingly, recent studies utilized multi-omics data to classify ICC into two main subgroups, one with immune response genes as the main driving factor, while another is enriched with driver mutations in the genes associated with epigenetic regulations, such as IDH1 and IDH2. The two subgroups also show different hypermethylation patterns in the promoter regions. Additionally, the immune response induced by host-pathogen interactions, i.e., liver fluke infection, may further stimulate tumor growth through alterations of the tumor microenvironment. For in-depth functional studies, although many ICC cell lines have been globally established, these homogeneous cell lines may not fully explain the highly heterogeneous genetic contents of this disorder. Therefore, the advent of patient-derived xenograft and 3D patient-derived organoids as new disease models together with the understanding of evolution and genetic alterations of tumor cells at the single-cell resolution will likely become the main focus to fill the current translational research gaps of ICC in the future.

Human primary liver cancer-derived organoid cultures for disease modeling and drug screening

Human liver cancer research currently lacks in vitro models that can faithfully recapitulate the pathophysiology of the original tumor. We recently described a novel, near-physiological organoid culture system, wherein primary human healthy liver cells form long-term expanding organoids that retain liver tissue function and genetic stability. Here we extend this culture system to the propagation of primary liver cancer (PLC) organoids from three of the most common PLC subtypes: hepatocellular carcinoma (HCC), cholangiocarcinoma (CC) and combined HCC/CC (CHC) tumors. PLC-derived organoid cultures preserve the histological architecture, gene expression and genomic landscape of the original tumor, allowing for discrimination between different tumor tissues and subtypes, even after long-term expansion in culture in the same medium conditions. Xenograft studies demonstrate that the tumorogenic potential, histological features and metastatic properties of PLC-derived organoids are preserved in vivo. PLC-derived organoids are amenable for biomarker identification and drug-screening testing and led to the identification of the ERK inhibitor SCH772984 as a potential therapeutic agent for primary liver cancer. We thus demonstrate the wide-ranging biomedical utilities of PLC-derived organoid models in furthering the understanding of liver cancer biology and in developing personalized-medicine approaches for the disease.

Establishment of cholangiocarcinoma cell lines from patients in the endemic area of liver fluke infection in Thailand

Cholangiocarcinoma is a rare type of cancer which is an increasingly discernible health threat. The disease is usually very difficult in diagnosis and various treatment modalities are typically not effective. Cholangiocarcinoma is a complex and very heterogeneous malignancy characterized by tumor location, different risk factors, molecular profiling, and prognosis. Cancer cell lines represent an important tool for investigation in various aspects of tumor biology and molecular therapeutics. We established two cell lines, KKU-452 and KKU-023, which were derived from patients residing in the endemic area of liver fluke infection in Thailand. Both of tumor tissues have gross pathology of perihilar and intrahepatic mass-forming cholangiocarcinoma. Two cell lines were characterized for their biological, molecular and genetic properties. KKU-452 and KKU-023 cells are both adherent cells with epithelium morphology, but have some differences in their growth pattern (a doubling time of 17.9 vs 34.8 h, respectively) and the expression of epithelial bile duct markers, CK7 and CK19. Cytogenetic analysis of KKU-452 and KKU-023 cells revealed their highly complex karyotypes; hypertriploid and hypotetraploid, respectively, with multiple chromosomal aberrations. Both cell lines showed mutations in p53 but not in KRAS. KKU-452 showed a very rapid migration and invasion properties in concert with low expression of E-cadherin and high expression of N-cadherin, whereas KKU-023 showed opposite characters. KKU-023, but not KKU-452, showed in vivo tumorigenicity in xenografted nude mice. Those two established cholangiocarcinoma cell lines with unique characters may be valuable for better understanding the process of carcinogenesis and developing new therapeutics for the patients

Establishment and Characterization of Primary Cultures from Iranian Oral Squamous Cell Carcinoma Patients by Enzymatic Method and Explant Culture

OBJECTIVES

Oral Squamous Cell Carcinoma (OSCC) is the most frequent oral cancer worldwide. It is known as the eighth most common cancer in men and as the fifth most common cancer in women. Cytogenetic and biochemical studies in recent decades have emphasized the necessity of providing an appropriate tool for such researches. Cancer cell culture is a useful tool for investigations on biochemical, genetic, molecular and immunological characteristics of different cancers, including oral cancer. Here, we explain the establishment process of five primary oral cancer cells derived from an Iranian population.

MATERIALS AND METHODS

The specimens were obtained from five oral cancer patients. Enzymatic, explant culture and magnetic-activated cell sorting (MACS) methods were used for cell isolation. After quality control tests, characterization and authentication of primary oral cancer cells were performed by short tandem repeats (STR) profiling, chromosome analysis, species identification, and monitoring the growth, morphology and the expression of CD326 and CD133 markers.

RESULTS

Five primary oral cancer cells were established from an Iranian population. The flow cytometry results showed that the isolated cells were positive for CD326 and CD133 markers. Furthermore, the cells were free from mycoplasma, bacterial and fungal contamination. No misidentified or cross-contaminated cells were detected by STR analysis.

CONCLUSIONS

Human primary oral cancer cells provide an extremely useful platform for studying carcinogenesis pathways of oral cancer in Iranian population. They may be helpful in explaining the ethnic differences in cancer biology and the individuality in anticancer drug response in future studies.

A Microfluidic Chip for Detecting Cholangiocarcinoma Cells in Human Bile

Cholangiocarcinoma (CCA), a biliary tract malignancy, accounts for 20% of all liver cancers. There are several existing methods for diagnosis of CCA, though they are generally expensive, laborious, and suffer from low detection rates. Herein we first developed a means of partially purifying human bile for consequent injection into a microfluidic chip. Then, the novel microfluidic system, which featured 1) a cell capture module, 2) an immunofluorescence (IF) staining module featuring two CCA-specific biomarkers, and 3) an optical detection module for visualization of antibody probes bound to these CCA marker proteins, was used to detect bile duct cancer cells within partially purified bile samples. As a proof of concept, CCA cells were successfully captured and identified from CCA cell cultures, blood samples inoculated with CCA cells, and clinical bile specimens. In 7.5 ml of bile, this system could detect >2, 0, and 1 positive cells in advanced stage patients, healthy patients, and chemotherapy-treated patients, respectively. In conclusion, our microfluidic system could be a promising tool for detection of cancer cells in bile, even at the earliest stages of CCA when cancer cells are at low densities relative to the total population of epithelial cells.

Genomic and proteomic characterization of ARID1A chromatin remodeller in ampullary tumors

AT rich interactive domain 1A (ARID1A) is one of the most commonly mutated genes in a broad variety of tumors. The mechanisms that involve ARID1A in ampullary cancer progression remains elusive. Here, we evaluated the frequency of ARID1A and KRAS mutations in ampullary adenomas and adenocarcinomas and in duodenal adenocarcinomas from two cohorts of patients from Singapore and Romania, correlated with clinical and pathological tumor features, and assessed the functional role of ARID1A. In the ampullary adenocarcinomas, the frequency of KRAS and ARID1A mutations was 34.7% and 8.2% respectively, with a loss or reduction of ARID1A protein in 17.2% of the cases. ARID1A mutational status was significantly correlated with ARID1A protein expression level (P=0.023). There was a significant difference in frequency of ARID1A mutation between Romania and Singapore (2.7% versus 25%, P=0.04), suggestive of different etiologies. One somatic mutation was detected in the ampullary adenoma group. In vitro studies indicated the tumor suppressive role of ARID1A. Our results warrant further investigation of this chromatin remodeller as a potential early biomarker of the disease, as well as identification of therapeutic targets in ARID1A mutated ampullary cancers.

Establishment and characterization of a novel highly aggressive gallbladder cancer cell line, TJ-GBC2

BACKGROUND

Human gallbladder cancer (GBC) is an aggressive malignant neoplasm with a poor prognosis. The development of ideal tools for example tumor cell lines for investigating biological behavior, metastatic mechanism and potential treatment in GBCs is essential. In present study, we established and characterized a GBC cell line derived from primary tumor.

METHODS

Primary culture method was used to establish this cell line from a primary GBC. Light and electron microscopes, flow cytometry, chromosome analysis, heterotransplantation and immunohistochemistry were used to characterize the epidemic tumor characteristics and phenotypes of this cell line.

RESULTS

A novel GBC cell line, named TJ-GBC2, was successfully established from primary GBC. This cell line had characteristic epithelial tumor morphology and phenotypes in consistent with primary GBC, such as polygon and irregular cell shape, increased CA19-9 and AFP levels, and positive expression of CK7, CK8, CK19 and E-cadherin with negative vimentin. Moreover, about 25% of the cells were in the S-G2/M phase; abnormity in structure and number of chromosome with a peak number of 90-105 and 80% hypertetraploid were observed. Furthermore, this cell line had higher invasion and highest migration abilities compared to other GBC cell lines; and metastatic-related marker MMP9 and nm23 were positively expressed.

CONCLUSIONS

A novel highly aggressive GBC cell line TJ-GBC2 was successfully established from primary GBC. TJ-GBC2 cell line may be efficient tool for further investigating the biological behaviors, metastatic mechanism and potential targeted therapy of human GBC.

Simvastatin Induces Apoptosis and Suppresses Insulin-Like Growth Factor 1 Receptor in Bile Duct Cancer Cells

Background/Aims

Statins act as antineoplastic agents through the inhibition of cell proliferation. This study sought to demonstrate the effects of statins on extrahepatic bile duct cancer cell apoptosis and to document the changes in protein expression involved in tumor growth and suppression.

Methods

Human extrahepatic bile duct cancer cells were cultured. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were performed to determine the effect of statins on cell proliferation. Apoptosis was measured by a cell death detection enzyme-linked immunosorbent assay and caspase-3 activity assay, and flow cytometry was used to determine the percentage of cells in each phase of the cell cycle. The protein expression of Bax, Bcl-2, insulin-like growth factor 1 (IGF-1) receptor, extracellular signal-regulated kinase 1/2 (ERK1/2), and Akt was measured by Western blot analysis.

Results

Simvastatin suppressed cell proliferation by inducing G1 phase cell cycle arrest in bile duct cancer cells. Furthermore, it induced apoptosis via caspase-3 activation, downregulated the expression of the Bcl-2 protein, and enhanced the expression of the Bax protein. Moreover, simvastatin suppressed the expression of the IGF-1 receptor and IGF-1-induced ERK/Akt activation.

Conclusions

Simvastatin induces apoptosis in bile duct cancer cells, which suggests that it could be an antineoplastic agent for bile duct cancer.

Src as a Therapeutic Target in Biliary Tract Cancer

Src, a nonreceptor tyrosine kinase, is involved in a number of cancer-related signaling pathways and aberrantly activated in biliary tract cancer (BTC). This study aimed to elucidate the potential role of Src as a therapeutic target in BTC. We tested bosutinib, an orally active c-Src/Abl kinase inhibitor, alone or in combination with cytotoxic agents using 9 human BTC cell lines: SNU-245, SNU-308, SNU-478, SNU-869, SNU-1079, SNU-1196, HuCCT1, TFK-1, and EGI-1. Of these, SNU-308 and SNU-478 were relatively sensitive to bosutinib. Bosutinib abrogated phosphorylation of Src and its downstream molecules, and significantly increased G1 cell-cycle arrest and apoptosis. Bosutinib significantly inhibited cell migration and invasion and decreased epithelial-mesenchymal transition markers. Bosutinib combined with gemcitabine or cisplatin showed synergistic antiproliferative and antimigratory effects. In addition, this combination further inhibited phosphorylation of Src and its downstream molecules and decreased epithelial-mesenchymal transition marker expression compared with bosutinib alone. We established a SNU-478 xenograft model for in vivo experiments, because SNU-478 was more tumorigenic than SNU-308. Bosutinib combined with gemcitabine or cisplatin showed significantly more potent antitumor effects than bosutinib alone. Bosutinib combined with gemcitabine further decreased Ki-67 expression and Src phosphorylation, and further increased TUNEL expression. Our data suggest that Src might be a potential therapeutic target in BTC. Bosutinib demonstrated promising antitumor activity alone or in combination with gemcitabine or cisplatin in BTC cells, which supports further clinical development in patients with advanced BTC. Mol Cancer Ther; 15(7); 1515-24. ©2016 AACR.

Characterization of various cell lines from different ampullary cancer subtypes and cancer associated fibroblast-mediated responses

Background

Ampullary cancer is a relatively rare form of cancer and usually treated by pancreatoduodenectomy, followed by adjuvant therapy. The intestinal subtype is associated with markedly improved prognosis after resection. At present, only few cell lines are available for in vitro studies of ampullary cancer and they have not been collectively characterized.

Methods

We characterize five ampullary cancer cell lines by subtype maker expression, epithelial-mesenchymal transition (EMT) features, growth and invasion, drug sensitivity and response to cancer-associated fibroblast conditioned medium (CAF-CM).

Results

On the basis of EMT features, subtype marker expression, growth, invasion and drug sensitivity three types of cell lines could be distinguished: mesenchymal-like, pancreatobiliary-like and intestinal-like. Heterogeneous effects from the cell lines in response to CAF-CM, such as different growth rates, induction of EMT markers as well as suppression of intestinal differentiation markers were observed. In addition, proteomic analysis showed a clear difference in intestinal-like cell line from other cell lines.

Conclusion

Most of the available AMPAC cell lines seem to reflect a poorly differentiated pancreatobiliary or mesenchymal-like phenotype, which is consistent to their origin. We suggest that the most appropriate cell line model for intestinal-like AMPAC is the SNU869, while others seem to reflect aggressive AMPAC subtypes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2193-5) contains supplementary material, which is available to authorized users.

Establishment and characterization of a human intrahepatic cholangiocarcinoma cell line derived from an Italian patient

Biliary tract carcinoma is a rare malignancy with multiple causes, which underlie the different genetic and molecular profiles. Cancer cell lines are affordable models, reflecting the characteristics of the tumor of origin. They represent useful tools to identify molecular targets for treatment. Here, we established and characterized from biological, molecular, and genetic point of view, an Italian intrahepatic cholangiocarcinoma cell line (ICC), the MT-CHC01. MT-CHC01 cells were isolated from a tumor-derived xenograft. Immunophenotypical characterization was evaluated both at early and after stabilization passages. In vitro biological, genetic, and molecular features were also investigated. In vivo tumorigenicity was assessed in NOD/SCID mice. MT-CHC01cells retain epithelial cell markers, EPCAM, CK7, and CK19, and some stemness and pluripotency markers, i.e., SOX2, Nanog, CD49f/integrin-α6, CD24, PDX1, FOXA2, and CD133. They grow as a monolayer, with a population double time of about 40 h; they show a low migration and invasion potential. In low attachment conditions, they are able to form spheres and to growth in anchorage-independent manner. After subcutaneous injection, they retain in vivo tumorigenicity; the expression of biliary markers as CA19-9 and CEA were maintained from primary tumor. The karyotype is highly complex, with a hypotriploid to hypertriploid modal number (3n+/−) (52 to 77 chromosomes); low level of HER2 gene amplification, TP53 deletion, gain of AURKA were identified; K-RAS G12D mutation were maintained from primary tumor to MT-CHC01 cells. We established the first ICC cell line derived from an Italian patient. It will help to study either the biology of this tumor or to test drugs both in vitro and in vivo.

Establishment of a highly metastatic model with a newly isolated lung adenocarcinoma cell line

Lung cancer is the leading cause of malignancy-related death worldwide, and metastasis always results in a poor prognosis. However, therapeutic progress is hampered by a deficiency of appropriate pre-clinical metastatic models. To bridge this experimental gap, we developed an in vivo metastatic model via subcutaneous (s.c.) injection. The original cell line (XL-2) adopted in this model was newly isolated from the ascites of a patient with extensive metastases of lung adenocarcinoma, thereby avoiding any alteration of its initial molecular biology features from artificial serial cultivation. After comprehensive phenotypical and histological analysis, it was identified as a lung adenocarcinoma cell line. Additionally, the drug test showed that XL-2 cell line was sensitive to docetaxel, and resistant to doxorubicin, indicating it might serve as a cell line model of drug resistance for identifying mechanisms of tumors resistant to doxorubicin. Through this s.c. model, we further obtained a highly metastatic cell line (designated XL-2sci). The metastatic rate of mice in XL-2 group was 3/10, in contrast to the rate of 9/10 in XL-2sci group. Optical imaging, micro-computed tomography (micro-CT) scanning and Transwell assays were further applied to identify the enhanced metastatic capacity of Xl-2sci cells both in vivo and in vitro. Compared with XL-2 cells, ITRAQ labeled proteomics profiling study showed that some tumor metastasis-associated proteins were upregulated in XL-2sci cells, which also indicated the reliability of our model. Proliferation ability of XL-2 and XL-2sci were also evaluated. Results showed that highly metastatic XL-2sci possessed a decreased proliferation capacity versus XL-2, which demonstrated that its increased metastatic activity was not facilitated by a faster growth rate. In conclusion, we successfully developed an in vivo metastatic model using a newly established lung adenocarcinoma cell line, which will be beneficial to further investigations of lung cancer metastasis and to the development of anti-metastasis drugs.

WNT signaling drives cholangiocarcinoma growth and can be pharmacologically inhibited

Cholangiocarcinoma (CC) is typically diagnosed at an advanced stage and is refractory to surgical intervention and chemotherapy. Despite a global increase in the incidence of CC, little progress has been made toward the development of treatments for this cancer. Here we utilized human tissue; CC cell xenografts; a p53-deficient transgenic mouse model; and a non-transgenic, chemically induced rat model of CC that accurately reflects both the inflammatory and regenerative background associated with human CC pathology. Using these systems, we determined that the WNT pathway is highly activated in CCs and that inflammatory macrophages are required to establish this WNT-high state in vivo. Moreover, depletion of macrophages or inhibition of WNT signaling with one of two small molecule WNT inhibitors in mouse and rat CC models markedly reduced CC proliferation and increased apoptosis, resulting in tumor regression. Together, these results demonstrate that enhanced WNT signaling is a characteristic of CC and suggest that targeting WNT signaling pathways has potential as a therapeutic strategy for CC.

Knockdown of anterior gradient 2 expression extenuates tumor-associated phenotypes of SNU-478 ampulla of Vater cancer cells

Background

Anterior gradient 2 (AGR2) has been implicated in tumor-associated phenotypes such as cell viability, invasion and metastasis in various human cancers. However, the tumor promoting activity of AGR2 has not yet been determined in biliary tract cancers. Thus, we examined the expression of AGR2 and its tumor-promoting activity in biliary tract cancer cells in this study.

Methods

Expression of AGR2 mRNA and protein was analyzed by real time RT-PCR and western blotting, respectively. MTT assay was employed to measure cell viability and pulsed BrdU incorporation by proliferating cells was monitored by flow cytometry. Soft agar colony formation assay and transwell invasion assay were employed to determine anchorage-independent growth and in vitro invasion of the tumor cells, respectively. In vivo tumor formation was examined by injection of tumor cells into immunocompromised mice subcutaneously. Statistical analysis was performed with 2-tailed unpaired Student’s t-test for continuous data and with one-way ANOVA for multiple group comparisons. Bonferroni tests were used for post hoc 2-sample comparisons.

Results

AGR2 mRNA was detected in SNU-245, SNU-478, and SNU-1196 cell lines, and its protein expression was confirmed in SNU-478 and SNU-245 cell lines by western blot analysis. Knockdown of AGR2 expression with an AGR2-specific short hairpin RNA (shRNA) in SNU-478, an ampulla of Vater cancer cell line resulted in decreased cell viability and in decreased anchorage-independent growth by 98%. The AGR2 knockdown also increased the sensitivity of the cells to chemotherapeutic drugs, including gemcitabine, 5-fluorouracil and cisplatin. In addition, SNU-478 cells expressing AGR2-shRNA failed to form detectable tumor xenografts in nude mice, whereas control cells formed tumors with an average size of 179 ± 84 mm³ in 3 weeks. Overexpression of AGR2 in SNU-869 cells significantly increased cell viability through enhanced cell proliferation and the number of Matrigel™-invading cells compared with AGR2-negative SNU-869 cells.

Conclusions

Our findings implicate that AGR2 expression augments tumor-associated phenotypes by increasing proliferative and invasive capacities of the ampulla of Vater cancer cells.

Epidermal growth factor upregulates Skp2/Cks1 and p27kip1 in human extrahepatic cholangiocarcinoma cells

AIM: To evaluate the expression status of S-phase kinase-associated protein 2 (Skp2)/cyclin-dependent kinases regulatory subunit 1 (Cks1) and p27^kip1, and assess the prognostic significance of Skp2/Cks1 expression with p27^kip1 in patients with extrahepatic cholangiocarcinoma.

METHODS: Seventy-six patients who underwent curative resection for histologically confirmed extrahepatic cholangiocarcinoma at our institution from December 1994 to March 2008 were enrolled. Immunohistochemical staining for Skp2, Cks1, p27^kip1, and Ki67, along with other relevant molecular biologic experiments, were performed.

RESULTS: By Cox regression analyses, advanced age (> 65 years), advanced AJCC tumor stage, poorly differentiated histology, and higher immunostaining intensity of Skp2 were identified as independent prognostic factors in patients with extrahepatic cholangiocarcinoma. Exogenous epidermal growth factor (EGF, especially 0.1-10 ng/mL) significantly increased the proliferation indices by MTT assay and the mRNA levels of Skp2/Cks1 and p27^kip1 in SNU-1196, SNU-1079, and SNU-245 cells. The protein levels of Skp2/Cks1 (from nuclear lysates) and p27^kip1 (from cytosolic lysate) were also significantly increased in these cells. There were significant reductions in the protein levels of Skp2/Cks1 and p27^kip1 (from nuclear lysate) after the treatment of LY294002. By chromatin immunoprecipitation assay, we found that E2F1 transcription factor directly binds to the promoter site of Skp2.

CONCLUSION: Higher immunostaining intensity of Skp2/Cks1 was an independent prognostic factor for patients with extrahepatic cholangiocarcinoma. EGF upregulates the mRNA and protein levels of Skp2/Cks1 and p27^kip1via the PI3K/Akt pathway and direct binding of E2F1 transcription factor with the Skp2 promoter.

Silencing of CXCR4 inhibits tumor cell proliferation and neural invasion in human hilar cholangiocarcinoma

Background/Aims

To evaluate the expression of CXC motif chemokine receptor 4 (CXCR4) in the tissues of patients with hilar cholangiocarcinoma (hilar-CCA) and to investigate the cell proliferation and frequency of neural invasion (NI) influenced by RNAi-mediated CXCR4 silencing.

Methods

An immunohistochemical technique was used to detect the expression of CXCR4 in 41 clinical tissues, including hilar-CCA, cholangitis, and normal bile duct tissues. The effects of small interference RNA (siRNA)-mediated CXCR4 silencing were detected in the hilar-CCA cell line QBC939. Cell proliferation was determined by MTT. Expression of CXCR4 was monitored by quantitative real time polymerase chain reaction and Western blot analysis. The NI ability of hilar-CCA cells was evaluated using a perineural cell and hilar-CCA cell coculture migration assay.

Results

The expression of CXCR4 was significantly induced in clinical hilar-CCA tissue. There was a positive correlation between the expression of CXCR4 and lymph node metastasis/NI in hilar-CCA patients (p<0.05). Silencing of CXCR4 in tumor cell lines by siRNA led to significantly decreased NI (p<0.05) and slightly decreased cell proliferation.

Conclusions

CXCR4 is likely correlated with clinical recurrence of hilar-CCA. CXCR4 is involved in the invasion and proliferation of human hilar-CCA cell line QBC939, indicating that CXCR4 could be a promising therapeutic target for hilar-CCA.

Establishment and characterization of seven human breast cancer cell lines including two triple-negative cell lines

Permanently growing cell lines can be invaluable because of their usefulness in a variety of experimental situations. We report the characteristics of seven cell lines designated, SNU-306, SNU-334, SNU-1528, SNU-1553, SNU-1581, SNU-1958 and SNU-2372, which were established from three primary carcinomas, two pleural effusion, one pericardial effusion and one ascitic fluid samples obtained from seven Korean breast carcinoma patients. The histopathology of the primary tumors and their in vitro growth characteristics are described. DNA fingerprinting analysis and genetic alterations in the p53 and EGFR genes were conducted. The expression levels of the ER-α, PR, C-erbB2, E-cadherin, COX-2, MDR and MXR genes were investigated and sensitivity to anticancer drugs was screened. Growth was as adherent cells (four cell lines), floating aggregates (one cell line) and both (two cell lines). All lines were free of mycoplasma or bacteria and were proven unique by DNA fingerprinting analysis using 18 microsatellite markers. Estrogen receptor (ER) mRNA was highly expressed in five cell lines and low or undetectable in SNU-1958 and SNU-2372. Progesterone receptor (PR) mRNA was expressed only in the SNU-306. SNU-1958 and SNU-2372 were hormone receptor-negative and C-erbB2-negative (triple-negative). SNU-1528 had an in-frame deletion of 42 base pairs of p53 gene and showed over 20-fold resistance for taxol compared to the other cell lines. There were no mutation in the EGFR gene; COX-2 was expressed in four cell lines and MXR was expressed in two cell lines. These well-characterized seven breast cancer cell lines, which include two triple-negative cell lines, will be useful for the study of breast cancer biology.

Inhibition of Wnt signaling induces cell apoptosis and suppresses cell proliferation in cholangiocarcinoma cells

The aim of the present study was to explore possible gene therapy for hilar cholangiocarcinoma by detecting the activation of the Wnt signaling pathway in 4 cholangiocarcinoma cell lines and inhibiting its expression by RNA interference (RNAi) targeting key factors of this pathway. The expression levels of the Wnt pathway-related factors, Wnt2, Wnt3, β-catenin and transcription factor 4, and its target genes, c-myc and cyclin D1, in 4 cholangiocarcinoma cell lines were detected by RT-PCR, western blotting and immunofluorescence microscopy. After transfection of siRNAs targeting Wnt2 and β-catenin into FRH0201 cells, the expression of the Wnt pathway-related factors and its target genes was again detected, and the cell cycle distribution, apoptosis and proliferation were analyzed by flow cytometry and MTT assay. Activation of the Wnt pathway and the expression of its target genes were detected in all 4 cell lines at various levels. After siRNA transfection, the expression of the target genes in the FRH0201 cells was significantly downregulated. In addition, the Wnt pathway was blocked, cell apoptosis was enhanced and cell proliferation was suppressed. In conclusion, the Wnt signaling pathway is activated in cholangiocarcinoma cells. RNAi technology targeting Wnt2 and β-catenin may be a possible gene therapy for hilar cholangiocarcinoma.

The challenge of cholangiocarcinoma: dissecting the molecular mechanisms of an insidious cancer

Cholangiocarcinoma is a fatal cancer of the biliary epithelium and has an incidence that is increasing worldwide. Survival beyond a year of diagnosis is less than 5%, and therapeutic options are few. Known risk factors include biliary diseases such as primary sclerosing cholangitis and parasitic infestation of the biliary tree, but most cases are not associated with any of these underlying diseases. Numerous in vitro and in vivo models, as well as novel analytical techniques for human samples, are helping to delineate the many pathways implicated in this disease, albeit at a frustratingly slow pace. As yet, however, none of these studies has been translated into improved patient outcome and, overall, the pathophysiology of cholangiocarcinoma is still poorly understood. There remains an urgent need for new approaches and models to improve management of this insidious and devastating disease. In this review, we take a bedside-to-bench approach to discussing cholangiocarcinoma and outline research opportunities for the future in this field.

DNA promoter methylation as a diagnostic and therapeutic biomarker in gallbladder cancer

Gallbladder cancer is an infrequent neoplasia with noticeable geographical variations in its incidence around the world. In Chile, it is the main cause of death owing to cancer in women over 40 years old, with mortality rates up to 16.5 per 100,000 cases. The prognosis is poor with few therapeutic options; in advanced cases there is only a 10% survival at 5 years.

Several studies mention the possible role of DNA methylation in gallbladder carcinogenesis. This epigenetic modification affects tumor suppressor genes involved in regulation pathways, cell cycle control, cell adhesion and extracellular matrix degradation, in a sequential and cumulative way. Determining DNA methylation patterns would allow them to be used as biomarkers for the early detection, diagnosis, prognosis and/or therapeutic selection in gallbladder cancer.

Increases in p53 expression induce CTGF synthesis by mouse and human hepatocytes and result in liver fibrosis in mice

The tumor suppressor p53 has been implicated in the pathogenesis of non-cancer-related conditions such as insulin resistance, cardiac failure, and early aging. In addition, accumulation of p53 has been observed in the hepatocytes of individuals with fibrotic liver diseases, but the significance of this is not known. Herein, we have mechanistically linked p53 activation in hepatocytes to liver fibrosis. Hepatocyte-specific deletion in mice of the gene encoding Mdm2, a protein that promotes p53 degradation, led to hepatocyte synthesis of connective tissue growth factor (CTGF; the hepatic fibrogenic master switch), increased hepatocyte apoptosis, and spontaneous liver fibrosis; concurrent removal of p53 completely abolished this phenotype. Compared with wild-type controls, mice with hepatocyte-specific p53 deletion exhibited similar levels of hepatocyte apoptosis but decreased liver fibrosis and hepatic CTGF expression in two models of liver fibrosis. The clinical significance of these data was highlighted by two observations. First, p53 upregulated CTGF in a human hepatocellular carcinoma cell line by repressing miR-17-92. Second, human liver samples showed a correlation between CTGF and p53-regulated gene expression, which were both increased in fibrotic livers. This study reveals that p53 induces CTGF expression and promotes liver fibrosis, suggesting that the p53/CTGF pathway may be a therapeutic target in the treatment of liver fibrosis.

L1 cell adhesion molecule is a novel independent poor prognostic factor of extrahepatic cholangiocarcinoma

PURPOSE

Cholangiocarcinomas (CC) are associated with poor survival, but diagnostic markers and therapeutic targets have not yet been elucidated. We previously found aberrant expression of L1 cell adhesion molecule in intrahepatic CC and a role for L1 in the progression of intrahepatic CC. Here, we analyzed L1 expression in extrahepatic CC (ECC) and evaluated its prognostic significance.

EXPERIMENTAL DESIGN

We examined L1 expression in tumors from 75 ECC patients by immunohistochemistry. We analyzed the correlations between L1 expression and clinicopathologic factors as well as patient survival.

RESULTS

L1 was not expressed in normal extrahepatic bile duct epithelium but was aberrantly expressed in 42.7% of ECC tumors. High expression of L1 was detected at the invasive front of tumors and was significantly associated with perineural invasion (P < 0.01). Univariate analysis indicated that various prognostic factors such as histologic grade 3, advanced pathologic T stage and clinical stage, perineural invasion, nodal metastasis, and high expression of L1 were risk factors predicting patient survival. Multivariate analyses done by Cox's proportional hazards model showed that high expression of L1 (hazard ratio, 2.171; 95% confidence interval, 1.162-4.055; P = 0.015) and nodal metastasis (hazard ratio, 2.088; 95% confidence interval, 1.159-3.764; P = 0.014) were independent risk factors for patient death.

CONCLUSIONS

L1 was highly expressed in 42.7% of ECC and its expression was significantly associated with perineural invasion. High expression of L1 and nodal metastasis were independent poor prognostic factors predicting overall survival in patients with ECC.

Non-adhesive organ culture of human biliary epithelium with stroma

OBJECTIVE

Explanted tissue has been shown to keep adult human cells in organ culture with a preserved morphology for at least one month as spheres in a non-adhesive organ culture. In the present study, we explored whether also human biliary epithelium can be grown in this manner, because the result may be of interest in studies of hepato-biliary-pancreatic carcinogenesis. MATERIAL AND METHODS. Small tissue samples were obtained from the gallbladder wall of patients who had been operated upon with cholecystectomy. Fragments of about 300 microm in diameter from each patient were cultured and investigated with light microscopy at the time of explantation and after 5, 10, 20, 30 and 40 days of culture. Scanning and transmission electron microscopy were performed to demonstrate the ultrastructure. Incubation of cultured fragments with the vital dyes revealed a viable epithelium.

RESULTS

At the time of explantation, all the tissue fragments had a rough appearance with an uneven, torn periphery, while during the first few days of culture they became rounder with a smooth-looking surface covering the entire circumference. This spheroid morphology persisted for the remainder of the culture period. The core of the fragments harboured connective tissue with vascular elements, fibroblasts and leucocytes. Immunostaining for cytokeratin 7, 19 and 20 revealed a strong positive staining of the epithelium.

CONCLUSIONS

These results show that biliary epithelium can be grown in vitro in a non-adhesive organ culture with their stroma.

Two distinct pathways of p16 gene inactivation in gallbladder cancer

AIM: To examine the mechanism of inactivation of the p16 gene in gallbladder cancer, and to investigate p16 alterations and their correlation with clinicopathological features.

METHODS: Specimens were collected surgically from 51 patients with gallbladder cancer. We evaluated the status of protein expression, loss of heterozygosity (LOH), homozygous deletion and promoter hypermethylation using immunohistochemistry, microsatellite analysis, quantitative real-time polymerase chain reaction (PCR) and methylation-specific PCR, respectively. In addition, mutations were examined by direct DNA sequencing.

RESULTS: Homozygous deletions of the p16 gene exon2, LOH at 9p21-22, p16 promoter hypermethylation, and loss of p16 protein expression were detected in 26.0% (13/50), 56.9% (29/51), 72.5% (37/51) and 62.7% (32/51), respectively. No mutations were found. LOH at 9p21 correlated with the loss of p16 protein expression (P < 0.05). Homozygous deletion of the p16 gene, a combination LOH and promoter hypermethylation, and multiple LOH at 9p21 were significantly correlated with the loss of p16 protein expression (P < 0.05). LOH at 9p21 and promoter hypermethylation of the p16 gene were detected in 15.4% (2/13) and 92.3% (12/13) of the tumors with homozygous deletion of the p16 gene, respectively. P16 alterations were not associated with clinicopathological features.

CONCLUSION: Our results suggest that LOH and homozygous deletion may be two distinct pathways in the inactivation of the p16 gene. Homozygous deletion, a combination of LOH and promoter hypermethylation, and multiple LOH are major mechanisms of p16 inactivation in gallbladder cancer.