Distribution and density of tertiary lymphoid structures predict clinical outcome in intrahepatic cholangiocarcinoma

BACKGROUND & AIMS

The prognostic value and clinical relevance of tertiary lymphoid structures (TLSs) in intrahepatic cholangiocarcinoma (iCCA) remain unclear. Thus, we aimed to investigate the prognostic value and functional involvement of TLSs in iCCA.

METHODS

We retrospectively included 962 patients from 3 cancer centers across China. The TLSs at different anatomic subregions were quantified and correlated with overall survival (OS) by Cox regression and Kaplan-Meier analyses. Multiplex immunohistochemistry (mIHC) was applied to characterize the composition of TLSs in 39 iCCA samples.

RESULTS

A quaternary TLS scoring system was established for the intra-tumor region (T score) and peri-tumor region (P score) respectively. T scores positively correlated with favorable prognosis (p <0.001), whereas a high P score signified worse survival (p <0.001). mIHC demonstrated that both T follicular helper and regulatory T cells were significantly increased in intra-tumoral TLSs compared to peri-tumoral counterparts (p <0.05), and regulatory T cell frequencies within intra-tumoral TLSs were positively associated with P score (p <0.05) rather than T score. Collectively, the combination of T and P scores stratified iCCAs into 4 immune classes with distinct prognoses (p <0.001) that differed in the abundance and distribution pattern of TLSs. Patients displaying an immune-active pattern had the lowest risk, with 5-year OS rates of 68.8%, whereas only 3.4% of patients with an immune-excluded pattern survived at 5 years (p <0.001). The C-index of the immune class was statistically higher than the TNM staging system (0.73 vs. 0.63, p <0.001). These results were validated in an internal and 2 external cohorts.

CONCLUSIONS

The spatial distribution and abundance of TLSs significantly correlated with prognosis and provided a useful immune classification for iCCA. T follicular helper and regulatory T cells may play a critical role in determining the functional orientation of spatially different TLSs.

LAY SUMMARY

Tertiary lymphoid structures (TLSs) are associated with favorable prognosis in a number of cancers. However, their role in intrahepatic cholangiocarcinoma (iCCA) remains unclear. Herein, we comprehensively evaluated the spatial distribution, abundance, and cellular composition of TLSs in iCCA, and revealed the opposite prognostic impacts of TLSs located within or outside the tumor. This difference could be mediated by the different immune cell subsets present within the spatially distinct TLSs. Based on our analysis, we were able to stratify iCCAs into 4 immune subclasses associated with varying prognoses.

Single-cell atlas of tumor cell evolution in response to therapy in hepatocellular carcinoma and intrahepatic cholangiocarcinoma

BACKGROUND & AIMS

Intratumor molecular heterogeneity is a key feature of tumorigenesis and is linked to treatment failure and patient prognosis. Herein, we aimed to determine what drives tumor cell evolution by performing single-cell transcriptomic analysis.

METHODS

We analyzed 46 hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA) biopsies from 37 patients enrolled in interventional studies at the NIH Clinical Center, with 16 biopsies collected before and after treatment from 7 patients. We developed a novel machine learning-based consensus clustering approach to track cellular states of 57,000 malignant and non-malignant cells including tumor cell transcriptome-based functional clonality analysis. We determined tumor cell relationships using RNA velocity and reverse graph embedding. We also studied longitudinal samples from 4 patients to determine tumor cellular state and its evolution. We validated our findings in bulk transcriptomic data from 488 patients with HCC and 277 patients with iCCA.

RESULTS

Using transcriptomic clusters as a surrogate for functional clonality, we observed an increase in tumor cell state heterogeneity which was tightly linked to patient prognosis. Furthermore, increased functional clonality was accompanied by a polarized immune cell landscape which included an increase in pre-exhausted T cells. We found that SPP1 expression was tightly associated with tumor cell evolution and microenvironmental reprogramming. Finally, we developed a user-friendly online interface as a knowledge base for a single-cell atlas of liver cancer.

CONCLUSIONS

Our study offers insight into the collective behavior of tumor cell communities in liver cancer as well as potential drivers of tumor evolution in response to therapy.

LAY SUMMARY

Intratumor molecular heterogeneity is a key feature of tumorigenesis that is linked to treatment failure and patient prognosis. In this study, we present a single-cell atlas of liver tumors from patients treated with immunotherapy and describe intratumoral cell states and their hierarchical relationship. We suggest osteopontin, encoded by the gene SPP1, as a candidate regulator of tumor evolution in response to treatment.

Expression patterns and prognostic significances of RRM1 and ERCC1 in pancreatic carcinoma and cholangiocarcinoma

BACKGROUND

Aggressive pancreatobiliary tumors often require oxaliplatin-based therapies, instead of standard gemcitabine-based therapy and biomarker studies at diagnosis to decide the appropriate therapeutic regimen. The ribonucleotide Reductase catalytic subunit M1 (RRM1) and excision repair cross-complementing gene-1 (ERCC1) are related to DNA synthesis and repair and essential in this regard. However, apart from the therapeutic benefit, their prognostic implication is controversial.

METHODS

In this retrospective study, paraffin-embedded tissue from 51 cases of pancreatic cancer and 29 cases of cholangiocarcinoma were evaluated for RRM1 and ERCC1 expression by immunohistochemical technique along with 18 control pancreatic and biliary tissues. The semiquantitatively H score was calculated based on stain distribution and stain intensities.

RESULTS

Both RRM1 and ERCC1 expression were high in tumor epithelium than in controls (RRM1: the difference was statistically significant in cholangiocarcinoma (P = 0.008); ERCC1: the difference was statistically significant both in pancreatic and cholangiocarcinoma (P < 0.05)]. However, no correlation was noted between RRM1 and ERCC1-low and high tumors with histological markers of prognosis and overall survival in these patients.

CONCLUSIONS

The present study adds further evidence against the controversy that if RRM1 and ERCC1 expression in pancreatic and biliary carcinomas have any prognostic significance apart from their proven therapeutic benefits in these tumors.

Long-term live imaging and multiscale analysis identify heterogeneity and core principles of epithelial organoid morphogenesis

BACKGROUND

Organoids are morphologically heterogeneous three-dimensional cell culture systems and serve as an ideal model for understanding the principles of collective cell behaviour in mammalian organs during development, homeostasis, regeneration, and pathogenesis. To investigate the underlying cell organisation principles of organoids, we imaged hundreds of pancreas and cholangiocarcinoma organoids in parallel using light sheet and bright-field microscopy for up to 7 days.

RESULTS

We quantified organoid behaviour at single-cell (microscale), individual-organoid (mesoscale), and entire-culture (macroscale) levels. At single-cell resolution, we monitored formation, monolayer polarisation, and degeneration and identified diverse behaviours, including lumen expansion and decline (size oscillation), migration, rotation, and multi-organoid fusion. Detailed individual organoid quantifications lead to a mechanical 3D agent-based model. A derived scaling law and simulations support the hypotheses that size oscillations depend on organoid properties and cell division dynamics, which is confirmed by bright-field microscopy analysis of entire cultures.

CONCLUSION

Our multiscale analysis provides a systematic picture of the diversity of cell organisation in organoids by identifying and quantifying the core regulatory principles of organoid morphogenesis.

Quantitative magnetic resonance imaging predicts individual future liver performance after liver resection for cancer

The risk of poor post-operative outcome and the benefits of surgical resection as a curative therapy require careful assessment by the clinical care team for patients with primary and secondary liver cancer. Advances in surgical techniques have improved patient outcomes but identifying which individual patients are at greatest risk of poor post-operative liver performance remains a challenge. Here we report results from a multicentre observational clinical trial (ClinicalTrials.gov NCT03213314) which aimed to inform personalised pre-operative risk assessment in liver cancer surgery by evaluating liver health using quantitative multiparametric magnetic resonance imaging (MRI). We combined estimation of future liver remnant (FLR) volume with corrected T1 (cT1) of the liver parenchyma as a representation of liver health in 143 patients prior to treatment. Patients with an elevated preoperative liver cT1, indicative of fibroinflammation, had a longer post-operative hospital stay compared to those with a cT1 within the normal range (6.5 vs 5 days; p = 0.0053). A composite score combining FLR and cT1 predicted poor liver performance in the 5 days immediately following surgery (AUROC = 0.78). Furthermore, this composite score correlated with the regenerative performance of the liver in the 3 months following resection. This study highlights the utility of quantitative MRI for identifying patients at increased risk of poor post-operative liver performance and a longer stay in hospital. This approach has the potential to inform the assessment of individualised patient risk as part of the clinical decision-making process for liver cancer surgery.

Synchronous Double Bile Duct Cancers with Distinct Genetic Features

A 69-year-old man was referred to our hospital because of appetite loss. Imaging showed a nodular tumor in the perihilar bile duct and a second flat lesion in the distal bile duct. Right hepatopancreaticoduodenectomy was performed, and the histopathological findings demonstrated that the perihilar and distal lesions were moderately and poorly differentiated adenocarcinoma, respectively, and anatomically separated. Furthermore, the resected specimens showed no pancreaticobiliary maljunction. Histological and TP53 gene analyses in a rare case of synchronous double bile duct cancers suggest that there are various genetic pathways through which bile duct cancer develops, highlighting the complexity of its pathogenesis.

The Hippo Pathway and YAP Signaling: Emerging Concepts in Regulation, Signaling, and Experimental Targeting Strategies With Implications for Hepatobiliary Malignancies

The Hippo pathway and its effector protein YAP (a transcriptional coactivator) have been identified as important in the biology of both hepatocellular carcinoma and cholangiocarcinoma. First identified as a tumor suppressor pathway in Drosophila, the understanding of the mammalian YAP signaling and its regulation continues to expand. In its "on" function, the canonical regulatory Hippo pathway, a well-described serine/threonine kinase module, regulates YAP function by restricting its subcellular localization to the cytoplasm. In contrast, when the Hippo pathway is "off," YAP translocates to the nucleus and drives cotranscriptional activity. Given the role of Hippo/YAP signaling in hepatic malignancies, investigators have sought to target these molecules; however, standard approaches have not been successful based on the pathways' negative regulatory role. More recently, additional regulatory mechanisms, such as tyrosine phosphorylation, of YAP have been described. These represent positive regulatory events that may be targetable. Additionally, several groups have identified potentiating feed-forward signaling for YAP in multiple contexts, suggesting other experimental therapeutic approaches to interrupt these signaling loops. Herein we explore the current data supporting alternative YAP regulatory pathways, review the described feed-forward signaling cascades that are YAP dependent, and explore targeting strategies that have been employed in preclinical models of hepatic malignancies.

IgG4-related Sclerosing Cholangitis Mimicking Cholangiocarcinoma Diagnosed by Endoscopic Ultrasound-guided Fine-needle Aspiration

A 58-year-old man was referred for obstructive jaundice. Imaging modalities revealed the presence of multiple pancreatic tumors and the stenosis of the middle common bile duct due to a hypoenhanced localized tumor. The multiple pancreatic tumors were histopathologically diagnosed as autoimmune pancreatitis by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). To differentiate between IgG4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma, we diagnosed the biliary tumor as IgG4-SC by EUS-FNA because of insufficient pathological materials obtained in a transpapillary manner. We herein report a case of IgG4-SC diagnosed by EUS-FNA.

Neuroendocrine Changes in Cholangiocarcinoma Growth

Cholangiocarcinoma (CCA) is a highly aggressive malignancy that emerges from the biliary tree. There are three major classes of CCA-intrahepatic, hilar (perihilar), or distal (extrahepatic)-according to the location of tumor development. Although CCA tumors are mainly derived from biliary epithelia (i.e., cholangiocytes), CCA can be originated from other cells, such as hepatic progenitor cells and hepatocytes. This heterogeneity of CCA may be responsible for poor survival rates of patients, limited effects of chemotherapy and radiotherapy, and the lack of treatment options and novel therapies. Previous studies have identified a number of neuroendocrine mediators, such as hormones, neuropeptides, and neurotransmitters, as well as corresponding receptors. The mediator/receptor signaling pathways play a vital role in cholangiocyte proliferation, as well as CCA progression and metastases. Agonists or antagonists for candidate pathways may lead to the development of novel therapies for CCA patients. However, effects of mediators may differ between healthy or cancerous cholangiocytes, or between different subtypes of receptors. This review summarizes current understandings of neuroendocrine mediators and their functional roles in CCA.

The tumour microenvironment and immune milieu of cholangiocarcinoma

Tumour microenvironment is a complex, multicellular functional compartment that, particularly when assembled as an abundant desmoplastic reaction, may profoundly affect the proliferative and invasive abilities of epithelial cancer cells. Tumour microenvironment comprises not only stromal cells, mainly cancer-associated fibroblasts, but also immune cells of both the innate and adaptive system (tumour-associated macrophages, neutrophils, natural killer cells, and T and B lymphocytes), and endothelial cells. This results in an intricate web of mutual communications regulated by an extensively remodelled extracellular matrix, where the tumour cells are centrally engaged. In this regard, cholangiocarcinoma, in particular the intrahepatic variant, has become the focus of mounting interest in the last years, largely because of the lack of effective therapies despite its rising incidence and high mortality rates worldwide. On the other hand, recent studies in pancreatic cancer, which similarly to cholangiocarcinoma, is highly desmoplastic, have argued against a tumour-promoting function of the tumour microenvironment. In this review, we will discuss recent developments concerning the role of each cellular population and their multifaceted interplay with the malignant biliary epithelial counterpart. We ultimately hope to provide the working knowledge on how their manipulation may lead to a therapeutic gain in cholangiocarcinoma.

The Role of Stroma in Cholangiocarcinoma: The Intriguing Interplay between Fibroblastic Component, Immune Cell Subsets and Tumor Epithelium

Cholangiocarcinoma (CCA) is a severe and mostly intractable adenocarcinoma of biliary epithelial cells. A typical feature of CCA is its highly desmoplastic microenvironment containing fibrogenic connective tissue and an abundance of immune cells (T lymphocytes, Natural Killer (NK) cells, and macrophages) infiltrating tumor epithelium. This strong desmoplasia is orchestrated by various soluble factors and signals, suggesting a critical role in shaping a tumor growth-permissive microenvironment that is responsible for CCA poor clinical outcome. Indeed stroma not only provides an abundance of factors that facilitate CCA initiation, growth and progression, but also a prejudicial impact on therapeutic outcome. This review will give an overview of tumor-stroma signaling in a microenvironment critically regulating CCA development and progression. Identification of CCA secreted factors by both the fibroblast component and immune cell subsets might provide ample opportunities for pharmacological targeting of this type of cancer.

Sarcomatous intrahepatic cholangiocarcinoma: Case report and literature review

RATIONALE

Sarcomatous intrahepatic cholangiocarcinoma is a rare histological variant of cholangiocarcinoma (ICC). Previous medical literature has not mentioned the prevalence of this kind of disease, but a poorer prognosis than that of ordinary ICC was indicated. The diagnosis of the sarcomatous ICC is established on histopathological and immunohistochemical examinations. In this article, we present a new case of a patient with sarcomatous ICC who had no radiographic sign of intrahepatic tumor preoperatively.

PATIENT CONCERNS

A 63-year-old man was noted with cholecystolithiasis and right upper abdominal pain. Liver function was within normal limits, although the gamma-glutamyl transpeptidase level was elevated. Serum carbohydrate antigen 19-9 level was elevated. Radiography showed atrophy of the left lobe of the liver, high-intensity signals on T1 weighted images, and low/high-intensity signals on T2 weighted images in hepatic ducts.

DIAGNOSES

The preoperative diagnoses were hepatolithiasis, choledocholithiasis, and cholecystolithiasis.

INTERVENTIONS

Exploratory laparotomy, adhesion release, cholecystectomy, choledocholithotomy, and T tube drainage were performed. During the surgery, an ill-defined tumor was detected on the atrophic left lateral lobe of the liver. Hepatic left lateral lobectomy was performed to remove the mass.

OUTCOMES

The final diagnosis of sarcomatous ICC was made by histopathology after surgery. No evidence of local recurrence or distant metastasis was noted on imaging during follow-up.

LESSONS

Although rare, sarcomatous ICC does exist in patients presented with cholecystolithiasis and liver atrophy. Surgeons should be aware of the existence of sarcomatous ICC due to the poor prognosis. We recommend that multidisciplinary approaches may be key to improve prognosis, including adjuvant chemotherapy or radiotherapy.

Coexistence of double gallbladder with cholangiocarcinoma: A case report

RATIONALE

Gallbladder duplication is a rare congenital disorder, which could cause an increasing risk of complications during surgery. The coexistence of cholangiocarcinoma with double gallbladder is extremely rare, which might lead to an even higher possibility of misdiagnosis and postsurgery complications.

PATIENT CONCERNS

A 58-year-old female was presented with abdominal pain and jaundice. Abdominal ultrasonography showed duplication of gallbladder, one of which with a thickened wall and a rough surface. This was also confirmed by an abdominal computed tomography (CT), magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) scan. During the surgery, we found a tumor inside one bile duct. The postsurgery pathology showed adenosquamous carcinoma.

DIAGNOSES

Gallbladder duplication, cholangiocarcinoma.

INTERVENTIONS

The tumor was removed by surgery.

OUTCOMES

The patient died of tumor relapse six months after surgery.

LESSONS

This is the first reported case with coexistence of gallbladder duplication and cholangiocarcinoma, which was diagnosed by abdominal ultrasound, CT and MRCP, as well as further confirmed in surgery and pathology. This case emphasized the importance of a thorough examination of gallbladder before surgery, especially in those cases with suspected double gallbladder, since each gallbladder could have the possibility of an independent cholangiocarcinoma.

Sumoylation in p27kip1 via RanBP2 promotes cancer cell growth in cholangiocarcinoma cell line QBC939

BACKGROUND

Cholangiocarcinoma is one of the deadly disease with poor 5-year survival and poor response to conventional therapies. Previously, we found that p27kip1 nuclear-cytoplasmic translocation confers proliferation potential to cholangiocarcinoma cell line QBC939 and this process is mediated by crm-1. However, no other post-transcriptional regulation was found in this process including sumoylation in cholangiocarcinoma.

RESULTS

In this study, we explored the role of sumoylation in the nuclear-cytoplasmic translocation of p27kip1 and its involvement of QBC939 cells' proliferation. First, we identified K73 as the sumoylation site in p27kip1. By utilizing plasmid flag-p27kip1, HA-RanBP2, GST-RanBP2 and His-p27kip1 and immunoprecipitation assay, we validated that p27kip1 can serve as the sumoylation target of RanBP2 in QBC939. Furthermore, we confirmed crm-1's role in promoting nuclear-cytoplasmic translocation of p27kip1 and found that RanBP2's function relies on crm-1. However, K73R mutated p27kip1 can't be identified by crm-1 or RanBP2 in p27kip1 translocation process, suggesting sumoylation of p27kip1 via K73 site is necessary in this process by RanBP2 and crm-1. Phenotypically, the overexpression of either RanBP2 or crm-1 can partially rescue the anti-proliferative effect brought by p27kip1 overexpression in both the MTS and EdU assay. For the first time, we identified and validated the K73 sumoylation site in p27kip1, which is critical to RanBP2 and crm-1 in p27kip1 nuclear-cytoplasmic translocation process.

CONCLUSION

Taken together, targeted inhibition of sumoylation of p27kip1 may serve as a potentially potent therapeutic target in the eradication of cholangiocarcinoma development and relapses.

Current diagnostic and management options in perihilar cholangiocarcinoma

Cholangiocarcinomas (CCAs) are heterogeneous biliary tract tumors with dismal prognosis. Perihilar CCA (pCCA) involves the large bile ducts of the hepatic hilum, and is the most common type of CCA. Primary sclerosing cholangitis (PSC) is an established risk factor for pCCA. Although the diagnosis of pCCA is challenging, recent advances have been made including cytologic techniques such as fluorescence in situ hybridization. Endoscopic ultrasound with sampling of regional lymph nodes is emerging as a valuable diagnostic modality in the diagnosis and staging of pCCA. Curative treatment options are limited to early stage disease, and include surgical resection and liver transplantation after neoadjuvant therapy. This underscores the importance of early detection, and the need for development of innovative diagnostic tools such as biomarkers. A dense desmoplastic tumor stroma plays an integral role in pCCA progression. The tumor stroma represents an additional target for development of new therapies. Herein, we discuss these advances in the diagnosis and treatment of pCCA.

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.

Index of convexity: A novel liver function index using Tc-GSA scintigraphy

AIM: To investigate the clinical usefulness of a newly developed index, the “index of convexity (IOC)”, for evaluating liver functional reserve using technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (Tc-GSA scintigraphy).

METHODS: In total, 349 patients underwent Tc-GSA scintigraphy. Dynamic planner images were obtained, and time activity curves of the liver and heart were generated and analyzed. Our focus was on the convex shape of the liver accumulation curve. We developed a method for evaluating the extent of convexity and calculated an index that we named the IOC. Clearance index and receptor index were also calculated. The correlations between each GSA index with other liver function tests and liver histopathology were evaluated.

RESULTS: Among the 3 indices generated by Tc-GSA, the IOC had the highest correlation with all other liver function tests (indocyanine green R15, albumin, prothrombin time, cholinesterase level, platelet count, and total bilirubin level). IOC can also differentiate between normal liver, chronic hepatitis, and liver cirrhosis with highest F ratio among GSA indices as determined by one-way analysis of variance. Receiver operating characteristic analysis demonstrated high diagnostic performance of IOC in the diagnosis of cirrhosis.

CONCLUSION: IOC is a very simple and reliable index for assessing liver functional reserve, which may prove to be useful in combination with the indocyanine green test for preoperative assessment of hepatic resection.

Resected biliary tract cancers: a novel clinical-pathological score correlates with global outcome

BACKGROUND

Biliary tract cancer presents a poor prognosis.

AIMS

The objective of this study is to find clinical-laboratory parameters like prognostic factors to select patients who can benefit from surgery and post-operative treatments.

METHODS

Between 2005 and 2010, 41 patients underwent radical surgery at our Institution. A novel score was retrospectively calculated assigning a grade to the clinical-laboratory findings at diagnosis. 0 and 1 point were respectively assigned to the normal or abnormal parameter. Two groups were identified: SCORE 0 and SCORE 1.

RESULTS

Patients with cholangiocarcinoma or Klatskin tumours or asymptomatic at diagnosis presented a significantly better overall survival (OS) than patients with different primary sites or who presented pain, jaundice or cholangitis. At univariate analysis, high levels of aspartate aminotransferase, alanine aminotransferase and CA19-9 before surgery, hyperbilirubinemia before and after surgery had a negative correlation with OS. A worse OS was observed in patients with a higher score (median OS in the "score 0" group=30.79 months vs. median OS in the "score 1"=17.98 months).

CONCLUSION

Our results suggest that pre and post-surgery clinical-laboratory parameters and the novel score, could be useful, especially for intrahepatic tumours, in predicting the outcome in patients undergoing surgery and in selecting patients to receive adjuvant therapy.

Endoscopic retrograde cholangiopancreatography in the diagnosis and management of cholangiocarcinoma

Cholangiocarcinomas (CCAs) are rare malignancies that arise from the biliary epithelium. Intrahepatic CCAs usually present as mass lesions that are asymptomatic or cause nonspecific systemic symptoms such as fatigue, fever, and weight loss. Hilar and extrahepatic tumors most commonly present with jaundice, though cholangitis also can be seen. Tumor markers such as carbohydrate antigen 19-9 and carcinoembryonic antigen have been used to diagnose CCA, but these are nonspecific and may be elevated in infection, inflammation, or any obstruction. Endoscopic retrograde cholangiopancreatography (ERCP) has been used for the diagnosis and management of CCA for many years. This article summarizes the data regarding the application of ERCP in the diagnosis and management of CCA.

[A case of primary liver carcinoma of intermediate (hepatocyte-cholangiocyte) phenotype: comparison of hemodynamics and histopathology]

A 58-year-old man was followed up for HBV-associated chronic hepatitis. A low echoic hepatic nodule 1.6cm in diameter developed in segment 8 of the liver. The tumor was hypervascular and showed enhancement on CV during hepatic arteriography (CTHA) and a defect on CT during arterial portography (CTAP). Strong enhancement, which lasted for 30 seconds, was observed at the margin of the tumor on single-level dynamic CTHA. The resected tumor was whitish, had no capsule, and consisted mainly of intermediate immature cells together with HCC-like and CCC-like tumor cells. These findings led to the diagnosis of primary liver carcinoma of intermediate (hepatocyte-cholangiocyte) phenotype. Cytokeratin (CK) 7, CK8, CK19, EMA and vimentin were positive and HP-1 and c-kit tests were negative on immunohistochemical staining. Staining with CD34+alphaSMA showed more muscular arterial vessels and sinusoid-like vessels in the peripheral zone of the tumor than in the central zone. Six months after the resection of the tumor, swollen abdominal lymph nodes were observed on US and CT, which aspiration needle biopsy showed to be metastasis of a hepatic tumor.

Lessons from the toxic bile concept for the pathogenesis and treatment of cholestatic liver diseases

Alterations in bile secretion at the hepatocellular and cholangiocellular levels may cause cholestasis. Formation of 'toxic bile' may be the consequence of abnormal bile composition and can result in hepatocellular and/or bile duct injury. The canalicular phospholipid flippase (Mdr2/MDR3) normally mediates biliary excretion of phospholipids, which normally form mixed micelles with bile acids and cholesterol to protect the bile duct epithelium from the detergent properties of bile acids. Mdr2 knockout mice are not capable of excreting phospholipids into bile and spontaneously develop bile duct injury with macroscopic and microscopic features closely resembling human sclerosing cholangitis. MDR3 mutations have been linked to a broad spectrum of hepatobiliary disorders in humans ranging from progressive familial intrahepatic cholestasis in neonates to intrahepatic cholestasis of pregnancy, drug-induced cholestasis, intrahepatic cholelithiasis, sclerosing cholangitis and biliary cirrhosis in adults. Other examples for bile injury due to the formation of toxic bile include the cholangiopathy seen in cystic fibrosis, after lithocholate feeding (in mice) and vanishing bile duct syndromes induced by drugs and xenobiotics. Therapeutic strategies for cholangiopathies may target bile composition/toxicity and the affected bile duct epithelium itself, and ideally should also have anti-cholestatic, anti-fibrotic and anti-neoplastic properties. Ursodeoxycholic acid (UDCA) shows some of these properties, but is of limited efficacy in the treatment of human cholangiopathies. By contrast to UDCA, its side chain-shortened homologue norUDCA undergoes cholehepatic shunting leading to a bicarbonate-rich hypercholeresis. Moreover, norUDCA has anti-inflammatory, anti-fibrotic and anti-proliferative effects, and stimulates bile acid detoxification. Upcoming clinical trials will have to demonstrate whether norUDCA or other side chain-modified bile acids are also clinically effective in humans. Finally, drugs for the treatment of cholangiopathies may target bile toxicity via nuclear receptors (FXR, PPARalpha) regulating biliary phospholipid and bile acid excretion.

AKT and ERK1/2 signaling in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinomas (ICC) are neoplasms that originate from cholangiocytes and can occur at any level of the biliary tree. Surgical resection is the current therapy of choice for this highly aggressive cancer. However, the 5-year survival still is poor, with high recurrence rates. Due to the intrahepatic growth a significant proportion of patients present with advanced disease and are not candidates for curative surgery or transplantation. The existing palliative options are of limited benefit and there is a great necessity for novel therapeutic options. In this article we review the role of the phosphoinositide 3-kinase(PI3K)/AKT and extracellular regulated kinase (ERK) signaling pathways in ICC and present new data on the prognostic value of these protein kinases. Finally, we discuss future upcoming therapeutic options based on targeting these signaling pathways.

Enhanced detection of cholangiocarcinoma with serum trypsinogen-2 in patients with severe bile duct strictures

BACKGROUND/AIMS

Primary sclerosing cholangitis (PSC) is associated with a high risk of cholangiocarcinoma. Our aim was to evaluate the diagnostic value of trypsinogen-1, trypsinogen-2, tumour-associated trypsin inhibitor, human chorionic gonadotropin beta and trypsin-2-alpha(1)-antitrypsin for cholangiocarcinoma and to compare them with CA19-9 and CEA.

METHODS

The study consisted of 84 patients with either PSC or cholangiocarcinoma or both referred for liver transplantation or other liver surgery. The serum concentrations were determined by time-resolved immunofluorometric assays.

RESULTS

Forty-six patients were transplanted due to PSC; in 3 of the explanted livers cholangiocarcinoma was found incidentally. All transplanted patients had severe biliary strictures together with cirrhosis or pre-cirrhosis. Twenty-nine of 38 patients with cholangiocarcinoma were candidates for intervention. In all, 8 patients had both PSC and cholangiocarcinoma. Receiver-operating characteristics curve analysis showed that serum trypsinogen-2 had the highest accuracy in differentiating between cholangiocarcinoma and PSC. The area under the curve (AUC) value was 0.804 for trypsinogen-2 and 0.613 for CA19-9. Serum trypsinogen-2 also showed the highest accuracy for differentiation between PSC and PSC with simultaneous cholangiocarcinoma with an AUC value of 0.759.

CONCLUSIONS

Our results suggest that serum trypsinogen-2 is a most useful marker for diagnosing patients with cholangiocarcinoma, and it is superior to serum CA19-9 and CEA.

Helical CT assessment on hilar cholangiocarcinoma: comparison value of arterial phase and portovenous phase correlation

OBJECTIVE

To study the correlation between the findings of hilar cholangiocarcinoma in hepatic arterial phase and portal venous phase. Attention will focus on whether the arterial phase imaging shows more detail than portal phase imaging.

MATERIAL AND METHOD

Descriptive study design with retrospective data collection in Srinagarind Hospital, Khon Kaen University. CT scans of the upper abdomen of 34 patients with pathologically proven hilar cholangiocarcinoma between 2002 and 2004 were reviewed for: (1) characteristic of the tumor; (2) adenopathy, (3) arterial involvement, (4) venous involvement, and (5) degree of biliary involvement on both the hepatic arterial and portal venous phases.

RESULTS

The correlation was high for characteristics of the tumor, the tumor enhancement pattern, and detection of adenopathy, degree of biliary involvement, and arterial involvement, but low for portal venous involvement which the portal venous phase detected better than the hepatic arterial phase.

CONCLUSION

In hilar type cholangiocarcinoma, the portal venous phase yielded the best findings. Furthermore, it showed all findings that were seen in the hepatic arterial phase. According to the present study, the authors suggest doing a pre-contrast study then a portal venous phase imaging for evaluation and diagnosis of hilar type cholangiocarcinoma. There is no necessity to perform hepatic arterial phase in hilar cholangiocarcinoma.

Clinical Utility of Coaxial Reservoir System for Hepatic Arterial Infusion Chemotherapy

PURPOSE

To test the feasibility and clinical utility of a reservoir with coaxial catheters (a 2.9-F microcatheter and a 5-F catheter) and a port (ie, coaxial reservoir) that was developed to perform repeated hepatic arterial infusion chemotherapy (HAIC) in patients with unresectable liver neoplasms.

MATERIALS AND METHODS

The coaxial reservoir was implanted in 64 patients with unresectable liver neoplasms as a result of difficulty in implanting a conventional reservoir with a 5-F catheter. The 2.9-F microcatheter tip was inserted into the gastroduodenal artery (n = 22), pancreaticoduodenal arcade (n = 20), or peripheral hepatic artery (n = 22) through the 5-F catheter, and a side hole created in the leading end of the microcatheter was oriented toward the proper hepatic artery. Technical success was defined by implantation of the coaxial reservoir and initiation of HAIC. The study endpoint was interruption of HAIC or death. Technical success and early and delayed complications were recorded.

RESULTS

The technical success rate was 100%. HAIC was repeated every 1-4 weeks during the mean follow-up period of 14.1 months. Arterial infusion chemotherapy was interrupted in 17 patients (27%) as a result of hepatic arterial occlusion (16%, n = 10), catheter dislocation (3%, n = 2), catheter occlusion (3%, n = 2), wound infection (3%, n = 2), or breakage of the port (2%, n = 1). Patency rates of the hepatic artery were 96%, 82%, and 50% at 6 months, 1 year, and 2 years after reservoir implantation, respectively.

CONCLUSION

Implantation of the coaxial reservoir is feasible, safe, and useful in expanding the indication of HAIC to patients with unresectable liver neoplasms.

Hepatitis B virus and intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is a rare type of primary liver cancer that arises from intrahepatic bile ducts. Its etiopathogenesis has been considered to be independent of the presence of chronic viral hepatitis infections or cirrhosis. These factors, particularly the hepatitis C virus, have been reported to play a role in the development of cholangiocarcinoma in a few studies, with inconclusive results. We report 2 cases of ICC that presented with a background of hepatitis B virus (HBV) infection and discuss the possible pathophysiological relationships between ICC and HBV infection, with an emphasis on the x gene of HBV.

Expression profiles of MUC mucins and trefoil factor family (TFF) peptides in the intrahepatic biliary system: physiological distribution and pathological significance

Mucin secreted by mucosal epithelial cells plays a role in the protection of the mucosal surface and also is involved in pathological processes. So far, MUC1-4, 5AC, 5B, 6-8, 11-13 and 15-17 genes coding the backbone mucin core protein have been identified in humans. Their diverse physiological distribution and pathological alterations have been reported. Trefoil factor family (TFF) peptides are mucin-associated molecules co-expressed with MUC mucins and involved in the maintenance of mucosal barrier and the biological behavior of epithelial and carcinoma cells. Intrahepatic biliary system is a route linking the bile canaliculi and the extrahepatic bile duct for the excretion of bile synthesized by hepatocytes. Biliary epithelial cells line in the intrahepatic biliary system, secreting mucin and other molecules involved in the maintenance and regulation of the system. In this review, the latest information regarding properties, expression profiles and regulation of MUC mucins and TFF peptides in the intrahepatic biliary system is summarized. In particular, we focus on the expression profiles and their significance of MUC mucins in developmental and normal livers, various hepatobiliary diseases and intrahepatic cholangiocarcinoma.

Perioperative management of primary liver cancer

AIM

To minimize the complications and mortality and improve the survival in primary liver cancer (PLC) patients undergoing hepatic resection.

METHODS

We conducted a retrospective analysis of 2143 PLC patients treated from January 1990 to January 2004. The patients were divided into two groups using January 1997 as a cut-off. Small tumor size (< 5 cm), preoperative redox tolerance index (RTI), vascular control method, and postoperative arterial ketone body ratio (AKBR) were used as indicators of surgical outcome.

RESULTS

Small tumors had less complications and lower mortality and higher overall survival rate. Use of RTI for selecting patients and types of hepatectomy, reduced complications (21.1% vs 11.0%) and mortality (1.6% vs 0.3%). The half liver vascular occlusion protocol (n = 523) versus the Pringle method (n = 476) showed that the former significantly reduced the postoperative complications (25.8% vs 11.9%) and mortality (2.3% vs 0.6%) respectively, and cut mean hospital stay was 3.5 d. Postoperative AKBR was a reliable indicator of the energy status in survivors.

CONCLUSION

RTI is of value in predicting hepatic functional reserve, half liver occlusion could protect the residual liver function, and AKBR measurement is a simple and accurate means of assessing the state of postoperative metabolism. Optimal perioperative management is an important factor for minimizing complications and mortality in patients undergoing hepatic resection.

Evaluation of VEGF A expression and microvascular density as prognostic factors in extrahepatic cholangiocarcinoma

OBJECTIVES

Angiogenesis is essential for tumor growth and metastasis. An association between microvessel density, a measure of tumor angiogenesis, and conventional prognostic variables has been shown for many different tumor entities. In extrahepatic cholangiocarcinoma, the VEGF expression and microvessel density have rarely been investigated.

METHODS

Paraffin-embedded specimens from 51 resected adenocarcinomas of the extrahepatic bile duct were immunostained for vascular endothelial growth factor A (VEGF A) and CD 34 to evaluate the microvessel density (MVD). VEGF A staining was evaluated by combining intensity and percentage of positive tumor cells, as low (expression equal or below the median), or high (above the median). Microvessel density was assessed using a method published by Weidner et al.

RESULTS

Median disease free survival (DFS) of the study group was 12.5 months (range, 1-66.3 months). DFS was calculated in the 39 patients with complete resection. It was significantly better in patients with low microvessel density than DFS in patients with high microvessel density (33 months (range, 3-66.3 months) vs. 21.8 months (range, 1.6-31.6 months); p=0.022). In contrast, VEGF A expression did not correlate with survival. There was a trend toward a higher VEGF A expression in highly vascularized tumors (p=0.08), but failed to reach statistic significance.

CONCLUSIONS

The present study indicates, that vascularisation has an important impact on survival of extrahepatic cholangiocarcinoma patients. Other molecules than VEGF A are probably involved in neovascularization in extrahepatic cholangiocarcinoma.

Roles of the MEK1/2 and AKT pathways in CXCL12/CXCR4 induced cholangiocarcinoma cell invasion

AIM: To evaluate the expression of C-X-C motif chemokine receptor 4 (CXCR4) and its signaling cascades, which were previously identified as a key factor for cancer cell progression and metastasis, in cholangiocarcinoma cell lines.

METHODS: The expression of CXCR4 and its signaling cascades were determined in the cholangiocarcinoma cell lines (RMCCA1 and KKU100) by Western blotting. The invasion assays and the detection of actin polymerization were tested in these cholangiocarcinoma cells treated with CXC chemokine ligand -12 (CXCL12).

RESULTS: Expression of CXCR4 was detected in both cholangiocarcinoma cell lines and activation of CXCR4 with CXCL12 triggered the signaling via the extracellular signal-regulated kinase-1/2 (ERK1/2) and phosphoinositide 3-kinase (PI3K) and induction of cholangiocarcinoma cell invasion, and displayed high levels of actin polymerization. Addition of CXCR4 inhibitor (AMD3100) abrogated CXCL12-induced phosphorylation of MEK1/2 and Akt in these cells. Moreover, treatment with MEK1/2 inhibitor (U0126) or PI3K inhibitor (LY294002) also attenuated the effect of CXCL12-induced cholangiocarcinoma cell invasion.

CONCLUSION: These results indicated that the activation of CXCR4 and its signaling pathways (MEK1/2 and Akt) are essential for CXCL12-induced cholangiocarcinoma cell invasion. This rises Implications on a potential role for the inhibition of CXCR4 or its signal cascades in the treatment of cholangiocarcinoma.

Proteasome inhibition-induces endoplasmic reticulum dysfunction and cell death of human cholangiocarcinoma cells

AIM: To determine if proteasome inhibition induces apoptosis in human cholangiocarcinoma cells, and if so, to elucidate the cellular mechanisms.

METHODS: Studies were performed in the human KMCH, KMBC, and Mz-ChA-1 cholangiocarcinoma, and normal rat cell lines. MG132, a peptide aldehyde, which inhibits the chymotrypsin-like activity of the proteaosome was employed for this study. Apoptosis was assessed morphologically by 4’-6-Diamidino-2-phenylindole (DAPI) nuclear staining and fluorescence microscopy. Mitochondrial membrane potential was examined using a fluorescent unquenching assay. Ultrastructural changes during cell death were examined using transmission electron microscopy (TEM). Caspase 3/7 activity was assessed using an enzymatic-based fluorescent assay. Cytosolic-free calcium concentrations were measured using Fura-2 and digitized fluorescent microscopy.

RESULTS: MG132, a proteasome inhibitor, induced apoptosis in all the cholangiocarcinoma cell lines examined. In contrast, minimal cytotoxicity was observed in normal rat cholangiocytes. Apoptosis was time- and -concentration-dependent. There was no change in the mitochondrial membrane potential between treated and untreated cells. Ultrastructural examination by transmission electron microscopy displayed the classic features of apoptosis, but in addition, there was also dramatic vacuolization of the endoplasmic reticulum (ER). Unexpectedly, no increase in caspase 3/7 activity was observed in MG132 treated cells, nor did the pancaspase inhibitor, Q-VD-OPh prevent cell death. The protein synthesis inhibitor, cycloheximide, blocked apoptosis induced by proteosome inhibitor indicating that ER dysfunction was dependent upon the formation of new proteins.

CONCLUSION: Proteosome inhibition induces ER dysfunction and caspase-independent cell death selectively in human cholangiocarcinoma cells. Proteasome inhibitors warrant evaluation as anticancer agents for the treatment of human cholangiocarcinoma.

Establishment and characterization of a cholangiocarcinoma cell line (RMCCA-1) from a Thai patient

AIM

To establish and characterize a new cell line derived from peripheral cholangiocarcinoma of a Thai patient.

METHODS

The peripheral cholangiocarcinoma specimen surgically obtained from the patient was aseptically processed by washing and mincing before culturing in Ham's F12 medium containing 10% fetal bovine serum. After 3 mo, when the cell line has become homogeneous and stabilized, several features were investigated, including growth characteristics, immunofluorescence staining for cytokeratins, expression of tumor markers, chromosomal analysis by G-banding and multicolour fluorescence in situ hybridization (mFISH), in vitro migration and invasion characteristics.

RESULTS

The RMCCA-1 cell line has been established. These cells proliferated as a monolayer with a population doubling time of 48 h. Immunofluorescence staining showed positive staining for human cytokeratin 7 and 19 verifying the biliary epithelial origin. RMCCA-1 secreted carbohydrate antigen 19-9 (CA19-9), but insignificant levels of carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP). Chromosome analysis identified aneuploidy karyotypes with a modal chromosome number of 59. RMCCA-1 exhibited a low level of in vitro invasiveness, but a high degree of motility. The cell line exhibited a significant number of chromosomal aberrations as shown by mFISH and G-banding methods.

CONCLUSION

A new cell line derived from peripheral cholangiocarcinoma of a Thai patient has been established. This cell line shows a low level of in vitro invasiveness, but a high degree of motility. It will serve as a valuable tool for further studies on tumor biology, molecular pathogenesis, metastatic mechanism and response to therapeutic drugs of cholangiocarcinoma.

Oxidative and nitrative DNA damage in animals and patients with inflammatory diseases in relation to inflammation-related carcinogenesis

Infection and chronic inflammation are proposed to contribute to carcinogenesis through inflammation-related mechanisms. Infection with hepatitis C virus, Helicobacter pylori and the liver fluke, Opisthorchis viverrini (OV), are important risk factors for hepatocellular carcinoma (HCC), gastric cancer and cholangiocarcinoma, respectively. Inflammatory bowel diseases (IBDs) and oral diseases, such as oral lichen planus (OLP) and leukoplakia, are associated with colon carcinogenesis and oral squamous cell carcinoma (OSCC), respectively. We performed a double immunofluorescence labeling study and found that nitrative and oxidative DNA lesion products, 8-nitroguanine and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), were formed and inducible nitric oxide synthase (iNOS) was expressed in epithelial cells and inflammatory cells at the site of carcinogenesis in humans and animal models. Antibacterial, antiviral and antiparasitic drugs dramatically diminished the formation of these DNA lesion markers and iNOS expression. These results suggest that oxidative and nitrative DNA damage occurs at the sites of carcinogenesis, regardless of etiology. Therefore, it is considered that excessive amounts of reactive nitrogen species produced via iNOS during chronic inflammation may play a key role in carcinogenesis by causing DNA damage. On the basis of our results, we propose that 8-nitroguanine is a promising biomarker to evaluate the potential risk of inflammation-mediated carcinogenesis.

Estrogens and the pathophysiology of the biliary tree

The scientific framework concerning estrogen effects on different tissues has expanded enormously during the last decades, when estrogen receptor (ER) subtypes were identified. Estrogens are not only essential for the female reproductive system, but they also control fundamental functions in other tissues including the cardiovascular system, bone, brain and liver. Recently, estrogens have been shown to target the biliary tree, where they modulate the proliferative and secretory activities of cholangiocytes, the epithelial cells lining bile ducts. By acting on both estrogen receptors (ER-α) and (ER-β) subtypes, and by activating either genomic or non-genomic pathways, estrogens play a key role in the complex loop of growth factors and cytokines, which modulates the proliferative response of cholangiocytes to damage. Specifically, estrogens activate intracellular signalling cascades [ERK1/2 (extracellular regulated kinases 1/2, PI3- kinase/AKT (phosphatidylinositol-3’ kinase/AKT)] typical of growth factors such as insulin like growth factor (IGF1), nerve growth factor (NGF) and vascular endothelial growth factor (VEGF), thus potentiating their action. In addition, estrogens stimulate the secretion of different growth factors in proliferating cholangiocytes. This review specifically deals with the recent advances related to the role and mechanisms by which estrogens modulate cholangiocyte functions in normal and pathological conditions.

Cyclooxygenase-2 and prostaglandin signaling in cholangiocarcinoma

Cholangiocarcinoma is a highly malignant epithelial neoplasm arising within the biliary tract and its incidence and mortality is rising. Early diagnosis is difficult and there is presently no effective treatment. Significant progress has been made over the past several years in defining the link between COX-2 and cholangiocarcinogenesis. Selective COX-2 inhibitors have been shown to inhibit cholangiocarcinoma cell growth in vitro and in animal models. However, recently, concerns have been raised about the cardiovascular side effect associated with some COX-2 inhibitors utilized at relatively high dose for antitumor chemoprevention, despite that these inhibitors have a proven safety profile when given as monotherapy to arthritis patients. Therefore, there is an urgent and practical need to develop novel chemopreventive strategy that simultaneously targets COX-2 signaling and other related key molecules in cholangiocarcinogenesis, such as EGFR or utilization of agents inhibiting COX-2 signaling in conjunction with other standard chemotherapy or radiation therapy; these approaches are expected to provide synergistic anti-tumor effect with lesser side effect. In this context, the recently delineated interplay between COX-2-derived PG signaling and other growth-regulatory pathways, such as EGFR, ErbB2, IL-6/GP130, HGF/Met, TGF-beta/Smad, and iNOS is expected to provide important therapeutic implications. This review will summarize the recent advances in understanding the mechanisms for COX-2-derived PG signaling in cholangiocarcinogenesis and focus on the newly unveiled interactions between PG cascade and other key signaling pathways that coordinately regulate cholangiocarcinoma growth. Knowledge on these aspects will help develop more effective therapeutic strategy targeting COX-2 and related key signaling molecules.

MUC1 and MUC5AC mucin expression in liver fluke-associated intrahepatic cholangiocarcinoma

AIM: To investigate the expressions of MUC1 and MUC5AC in intrahepatic cholangiocarcinoma (ICC). Association of expressions of mucins MUC1 and MUC5AC with clinical findings, metastasis, and survival of the liver fluke-associated ICC patients was determined.

METHODS: The expressions of MUC1 and MUC5AC mucins were examined by immunohistochemical staining in 87 cases of histologically-proven ICC. The expressions of mucins in relationship between clinicopathological significance and prognosis of the patients were evaluated.

RESULTS: Fifty-two patients (60%) exhibited both MUC1 and MUC5AC expressions, whereas 31% expressed either MUC1 or MUC5AC, and 9% expressed neither. High MUC1 immunoreactivity displayed a significant correlation with tumor progression as reflected by vascular invasion (P<0.001), whereas high expression of MUC5AC significantly correlated with neural invasion (P = 0.022) and advanced ICC stage (P = 0.008). Patients with high expression of MUC1 had a significantly shorter survival (P = 0.0002). According to multivariate analyses, MUC1 reactivity (P = 0.026), histological grading and stage of tumor represented the least probability of survival.

CONCLUSION: MUC1 is overexpressed in liver fluke-associated cholangiocarcinoma and relates to vascular invasion and poor prognosis, whereas MUC5AC mucin is neoexpressed and relates to neural invasion and advanced ICC stage. High MUC1 expression in tumor may be useful for predicting the poor outcome of ICC patients.

The delta opioid receptor 1 is expressed by proliferating bile ductules in rats with cholestasis: implications for the study of liver regeneration and malignant transformation of biliary epithelium

In sharp contrast with the normal adult liver, the fetal human and rat livers and the liver of rats with cholestasis secondary to bile duct resection express the preproenkephalin mRNA, which codes for the endogenous opioid peptide Met-enkephalin. Furthermore, Met-enkephalin immunoreactivity is detected in hepatocytes and in proliferating bile ductules in the cholestatic rat liver. These data suggest that in cholestasis endogenous opioids may have a local effect in the cholestatic liver. As endogenous opioids exert their effect by binding to opioid receptors, the presence of opioid receptors in the cholestatic livers would support the hypothesis that Met-enkephalin plays a role in situ. Preliminary data presented in this manuscript reveals the expression of the delta opioid receptor in the liver of rats with cholestasis. This finding suggests that there is a scenario in which Met-enkephalin can bind to opioid receptors in the liver in cholestasis to exert a local effect. In vivo studies in this model of cholestasis with the use of opioid agonist and antagonist will shed light on the possible role of opioidergic regulation of liver regeneration. Studies on the effect of opiate antagonists on the evolution of cholestasis in this animal model may provide insight into the mechanisms of liver regeneration. In addition, as some conditions associated with cholestasis and bile ductular proliferation can be complicated by malignancy, the expression of the delta opioid receptor in malignant tumors of the biliary tree merits research.

Mucin-producing cholangiocarcinoma: clinical experience of 24 cases in 16 years

OBJECTIVE

Mucin-producing cholangiocarcinoma (MPCC) is an uncommon biliary tract malignancy. This retrospective study was designed to investigate the clinical presentations, associated diseases, the value of tumor markers, and treatment and prognosis of MPCC.

MATERIAL AND METHODS

The study included 24 MPCC cases (7 M, 17 F) from 132 histopathology-proven cholangiocarcinoma patients seen between 1988 and 2003. MPCC and non-mucin-producing cholangiocarcinoma (non-MPCC) were compared.

RESULTS

Common clinical symptoms and signs included epigastric or right upper quadrant pain, fever and chills, jaundice, and anemia. Seventeen patients had mucobilia in surgical, cholangiographic, or CT findings. Biliary stones were found in 71% of MPCC patients. In detecting MPCC, a serum CA-19-9 level > 120 U/ml had 73% sensitivity, 41% specificity, 25% positive predictive value, 85% negative predictive value, and 48% accuracy in the 132 cholangiocarcinoma patients. The 1-, 2-, 3-, 4-, and 5-year survival rates were 44.3%, 33.8%, 28.1%, 21.1%, and 21.1%, respectively. Univariate analysis showed that tumor type (MPCC) was the only significant factor predicting survival when compared with non-MPCC patients in 5-year cumulative survival rates (21.1% versus 5.4%). MPCC patients receiving surgical resection had a prolonged median survival time (13 months versus 6 months) than those without resection.

CONCLUSIONS

MPCC clinical presentations were similar to non-MPCC in Taiwan except for more jaundice, fever and chills. The major factor predisposing to MPCC was biliary stones. Using serum CA19-9 levels greater than 120 U/ml was a diagnostic aid to detecting MPCC patients. MPCC patients had a better prognosis than non-MPCC patients. The recommended treatment for MPCC is surgical resection.

Effect of mutated IκBα transfection on multidrug resistance in hilar cholangiocarcinoma cell lines

AIM: To explore the expression effect of mutated IκBα transfection on multidrug resistance gene (MDR-1) in hilar cholangiocarcinoma cells by inhibiting the activity of nuclear transcription factor-κB (NF-κB).

METHODS: We used the mutated IκBα plasmid to transfect QBC₉₃₉HCVC+ cells and QBC939 cells, and electrophoretic gel mobility shift assay (EMSA) to detect the binding activity of NF-κB DNA and the effect of the transfecting mutated IκBα plasmid on multidrug resistance gene (MDR-1) in hilar cholangiocarcinoma cells and its expression protein (P-GP).

RESULTS: Plasmid DNA was digested by restriction enzymes Xbal and Hand III, and its product after electrophoresis showed two bands with a big difference in molecular weight, with a size of 4.9 kb and 1.55 kb respectively, which indicated that the carrier was successfully constructed and digested with enzymes. The radioactivity accumulation of QBC₉₃₉HCVC+ and QBC939 cells transfected with mutated IκBα plasmid was significantly lower than that of the control group not transfected with mutated IκBα plasmid. Double densimeter scanning showed that the relative signal density between the tansfection group and non-transfection group was significantly different, which proved that the mutated IκBα plasmid could inhibit the binding activity of NF-κB DNA in hilar cholangiocarcinoma cells. Compared to control group not transfected with m IκBα plasmid, the expression level of MDR-1mRNA in the QBC939 and QBC939HCVC+ cells transfected with mutated IκBα plasmid was lower. The expression intensity of P-GP protein in QBC939 and QBC939HCVC+ cells transfected with mutated IκBα was significantly lower than that of the control group not transfected with mutated IκBα plasmid.

CONCLUSION: The mutated IκBα plasmid transfection can markedly reverse the multidrug resistance of hilar cholangiocarcinoma cells. Interruption of NF-κB activity may become a new target in gene therapy for hilar cholangiocar-cinogenesic carcinoma.

Neutrophils enhance invasion activity of human cholangiocellular carcinoma and hepatocellular carcinoma cells: an in vitro study

BACKGROUND AND AIM

Tumor-mesenchymal interactions are involved in the mechanism of tumor invasion in several types of carcinoma. Mutual interactions between carcinoma cells and neutrophils, however, have been poorly understood. In the present study we examined the effect of neutrophils on invasion activities of carcinoma cells in vitro. Role of hepatocyte growth factor (HGF) as a mediator was also evaluated.

METHODS

Using a Matrigel invasion chamber, invasion activities of HuCC-T1 human cholangiocellular carcinoma cells and HepG2 hepatocellular carcinoma cells in response to recombinant HGF or neutrophils were evaluated.

RESULTS

Recombinant HGF dose-dependently increased invasion activities of HuCC-T1 and HepG2 cells. Neutrophils significantly enhanced invasion activities of these cells, which were suppressed to the respective basal levels with anti-HGF antibody. The carcinoma cells did not secrete HGF. Neutrophils cultivated in tumor condition medium (TCM) of HuCC-T1 or HepG2 cells secreted a significant level of HGF protein without increasing HGF mRNA expression. Treatment with heat or ultrafiltration of TCM of HuCC-T1 or HepG2 cells suggested carcinoma cell-derived HGF inducer(s) to be certain protein(s) with a molecular weight of more than 30 000.

CONCLUSIONS

The present study suggests the presence of mutual interactions between HuCC-T1/HepG2 carcinoma cells and neutrophils in tumor invasion via paracrine regulation mediated by neutrophil-derived HGF.

Detection of bcl-2 and bax expression and bcl-2/JH fusion gene in intrahepatic cholangiocarcinoma

AIM: To investigate the relationship between bcl-2 gene and its related protein bax and intrahepatic cholangiocellular carcinoma (CCC).

METHODS: Semi-nested in situ PCR (SNISPCR) and imm- unohistochemistry were performed to detect bcl-2/JH fusion gene and bcl-2, bax protein expression in 29 cases of CCC.

RESULTS: No bcl-2/JH fusion gene was found in all cases of CCC, 72.4% of 29 cases expressed bcl-2 protein. Bcl-2 protein expression was related to histopathological grades (P < 0.05). There was no corresponding relationship between bcl-2/JH fusion gene formation and bcl-2 protein expression in CCC (P < 0.05). Bax was expressed in 10.3% of 29 cases. The ratio of bcl-2 to bax in normal liver tissues (3.5 to 1) was different from that in tumor tissues (7.0 to 1).

CONCLUSION: It is suggested that bcl-2/JH fusion gene formation is not a frequent event and may not play an important role in the pathogenesis of CCC. However, aberrant ratio of bcl-2 to bax protein expression may be involved in the course of tumorigenesis of CCC. Abnormal bcl-2 protein expression may not be solely resulted from bcl-2/JH fusion gene.

Hemodynamics of intrahepatic cholangiocarcinoma: evaluation with single-level dynamic CT during hepatic arteriography

BACKGROUND

We determined the radiologic characteristics of intrahepatic cholangicarcinoma (ICC) on single-level dynamic computed tomography during hepatic arteriography (CTHA) and assessed the hemodynamics of the tumor.

METHODS

Eleven patients with pathologically confirmed ICC underwent single-level dynamic CTHA. After placing the catheter tip in the proper hepatic artery and running a 30-s continuous scan, scanning was performed every 15 or 30 s for 120 s. The change of contrast-enhancement pattern of the ICCs were interpreted retrospectively.

RESULTS

The pattern of enhancement was classified into two types: vascular and hypovascular. In the vascular type, the contrast enhancement gradually spread from each intratum oral artery and became mottled. It changed from a mottled and hypoattenuated pattern to an even and hyperattenuated appearance in comparison with the adjacent liver approximately 120 s after the injection of contrast agent. In the hypovascular type, the tumor was barely enhanced and remained hypoattenuated compared with the adjacent liver at 120 s after the beginning of the injection. The 11 ICCs were classified into eight vascular types and three hypovascular types. Intratumoral arteries were visualized in nine tumors: eight vascular types and one hypovascular type.

CONCLUSION

The contrast-enhancement pattern of ICC on single-level dynamic CTHA is related to the intratumoral artery.

The molecular pathogenesis of cholangiocarcinoma

Cholangiocarcinoma is rising in clinical importance because of increasing incidence, poor prognosis, and suboptimal response to therapy. Recent investigations into the underlying molecular mechanisms involved in cholangiocarcinogenesis and tumor growth have contributed greatly to our understanding of this disease. To review this topic, we discuss the molecular mechanisms in sections reflecting the unique features that allow cancer cells to develop and maintain a growth advantage. Through a better understanding of these mechanisms, improved and more specific diagnostic, therapeutic, and preventative strategies may be developed and hopefully improve the outcome of this devastating disease.

Anatomic and molecular pathology of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is the second most common malignant tumor of the liver, and ICC is reportedly increasing recently. ICC is usually adenocarcinoma with variable desmoplastic reaction, although there are several special or unusual histological features. ICC may arise at the large intrahepatic bile duct near the hepatic hilus and also from the bile ductules at the border of the hepatic parenchyma. On the anatomical level, the pathology of ICC differs depending on the region from which the ICC arises. At the large intrahepatic bile duct, ICC presents papillary growth and periductal infiltration. Some cases show extensive papillary growth and intraluminal spread with marked gastroenteric metaplasia. Mucus core protein 1 is expressed in aggressive ICC. ICC arising from ductules shares phenotypes of hepatocellular carcinoma. ICC in chronic biliary diseases, particularly arising in hepatolithiasis, presents precancerous lesions that include biliary epithelial dysplasia, as well as in-situ carcinoma. Chronic advanced hepatitis C is one of the background diseases of ICC. Chronic inflammation, with the upregulation of cyclooxygenase-2 and growth factors, and the formation of reactive oxygen species are one of the causative factors in the DNA damage of biliary epithelial cells. K- ras mutation and aberrant expression of p53 are found in one-third of ICCs. The latter may be due to mdm-2 upregulation. Hepatocyte growth factor/met and interleukin 6 (IL6)/IL6 receptor are involved in cell proliferation/mitoinhibition and apoptosis in ICC. Fibrous stroma formation and invasion involve the proliferation of Alpha-smooth muscle antigen-positive stromal cells, and cell-to-cell and cell-to-matrix interactions involving E-cadherin/catenin and CD44 and matrix proteinases may be involved in the invasion of ICC. Evasion of immune surveillance involving the Fas/FasL system is important in the malignant progression of ICC. Further molecular and genetic studies are mandatory to evaluate the pathogenesis and progression of ICC.

Diagnosis and management of cholangiocarcinomas: a comprehensive review

First described by Maximilian deStoll in 1777, cholangiocarcinoma remains to be a diagnostic and therapeutic challenge. The incidence of cholangiocarcinoma is of 2000-3000 cases a year in the US but much higher in Southeast Asia and Eastern Europe. Sclerosing cholangitis, ulcerative colitis, liver fluke infestations, hepatolithiasis, thorotrast exposure, choledochal cysts are associated with an increased risk. Recently, substantial progress has been achieved in the understanding of the cellular and molecular mechanisms playing a role in biliary carcinogenesis including oncogenes and tumor suppressor genes. Surgery alone can be a curative treatment in only a fraction of patients with a 5-year survival rate of 0-39%. The role of radiotherapy including intensification with intraoperative radiation therapy, brachytherapy or conformal external beam radiation therapy has not been proven. Experience with chemotherapy is not widespread in cholangiocarcinoma. Chemotherapy trials have mostly included small numbers of patients and there have been no large prospective randomized trials. Observed objective response rates have been between 0% and 40% with no complete remissions. Further studies are required to find out the impact of chemotherapy in the management of cholangiocarcinoma and search for newer agents with novel mechanisms of action that can be more active in cholangiocarcinoma should continue. Meanwhile prevention and early diagnosis of cholangiocarcinoma is essential. Efforts should also continue to discover means to detect high-risk patients with less invasive methods.

Patterns of regional lymph node involvement in intrahepatic cholangiocarcinoma of the left lobe

Lymph node involvement is an important prognostic factor in intrahepatic cholangiocarcinoma. Besides the nodes in the hepatoduodenal ligament, recent studies have suggested that the nodes around the cardiac portion of the stomach or along the gastric lesser curvature can be affected when the primary tumor is located in the left hepatic lobe. However, the distribution of metastatic nodes has not been well described in this disease. Thirteen patients with intrahepatic cholangiocarcinoma in the left hepatic lobe were enrolled in this study. Lymphatic mapping was performed by means of both histologic examination and reverse transcriptase-polymerase chain reaction assays. Nodal involvement around the cardiac portion of the stomach or along the lesser gastric curvature (left pathway) was found in 7 (54%) of 13 patients by histologic examination or reverse transcriptase-polymerase chain reaction, whereas positive nodes in the hepatoduodenal ligament (right pathway) were found in 6 (46%) of 13 patients. Two patients (15%) had positive nodes only in the left pathway. Therefore, for a more accurate clinical staging of intrahepatic cholangiocarcinoma in the hepatic left lobe, lymph nodes around the cardiac portion of the stomach and along the lesser gastric curvature should be examined in addition to nodes in the hepatoduodenal ligament.

Successful photodynamic therapy for nonresectable cholangiocarcinoma: a randomized prospective study

BACKGROUND & AIMS

In nonrandomized trials, photodynamic therapy (PDT) had a promising effect on nonresectable cholangiocarcinoma (NCC). This prospective, open-label, randomized, multicenter study with a group sequential design compared PDT in addition to stenting (group A) with stenting alone (group B) in patients with NCC.

METHODS

In patients with histologically confirmed cholangiocarcinoma, endoscopic or percutaneous double stenting was performed. Patients fulfilling inclusion criteria were randomized to group A (stenting and subsequent PDT) and group B (stenting alone). For PDT, Photofrin 2 mg/kg body wt was injected intravenously 2 days before intraluminal photoactivation (wavelength, 630 nm; light dose, 180 J/cm(2)). Further treatments were performed in cases of residual tumor in the bile duct. The primary outcome parameter was survival time. Secondary outcome parameters were cholestasis and quality of life.

RESULTS

PDT resulted in prolongation of survival (group A: n = 20, median 493 days; group B: n = 19, median 98 days; P < 0.0001). It also improved biliary drainage and quality of life.

CONCLUSIONS

PDT, given in addition to best supportive care, improves survival in patients with NCC. The study was terminated prematurely because PDT proved to be so superior to simple stenting treatment that further randomization was deemed unethical.

Celecoxib inhibits proliferation and induces apoptosis via prostaglandin E2 pathway in human cholangiocarcinoma cell lines

AIM: To evaluate the roles and mechanisms of celecoxib in inducing proliferation inhibition and apoptosis of human cholangiocarcinoma cell lines.

METHODS: Cyclooxygenase-2-overexpressing human cholangiocarcinoma cell line QBC939 and cyclooxygenase-2-deficient human cholangiocarcinoma cell line SK-CHA-1 were used in the present study. The anti-proliferative effect was measured by methabenzthiazuron (MTT) assay; apoptosis was determined by transferase-mediated dUTP nick end labeling (TUNEL) detection and transmission electron microscopy (TEM). Cell cycle was analyzed by flow cytometry (FCM). The PGE₂ levels in the supernatant of cultured cholangiocarcinoma cells were quantitated by enzyme-linked immunoabsordent assay (ELISA).

RESULTS: Celecoxib suppressed the production of PGE₂ and inhibited the growth of QBC939 cells. Celecoxib at 10, 20, and 40 μmol/L inhibited PGE₂ production by 26%, 58%, and 74% in QBC939 cells. The PGE₂ level was much lower constitutively in SK-CHA-1 cells (18.6 ± 3.2) compared with that in QBC939 (121.9 ± 5.6) cells (P < 0.01) and celecoxib had no significant influence on PGE₂ level in the SK-CHA-1 cells. The PGE₂ concentration in SK-CHA-1 cells also reduced but not significantly after treatment with celecoxib. The PGE₂ concentration in SK-CHA-1 cells was (16.5 ± 2.9) ng/well, (14.8 ± 3.4) ng/well, (13.2 ± 2.0) ng/well and (12.6 ± 3.1) ng/well respectively, when pre-treated with 1 μmol/L, 10 μmol/L, 20 μmol/L and 40 μmol/L of celecoxib for 48 h (P > 0.05, vs control). The anti-proliferation effect of celecoxib (20 μmol/L) on QBC939 cells was time-dependent, it was noticeable on day 2 (OD490 = 0.23 ± 0.04) and became obvious on day 3 (OD₄₉₀ = 0.31 ± 0.07) to day 4 (OD490 = 0.25 ± 0.06), and the OD₄₉₀ in the control group (day 1) was 0.12 ± 0.03 (P < 0.01, vs control). The anti-proliferation effect of celecoxib could be abolished by the addition of 200 pg/mL PGE₂. The proliferation of SK-CHA-1 cells was inhibited slightly by celecoxib, the cell density OD490 in the presence of celecoxib and in control group was 0.31 ± 0.04 and 0.42 ± 0.03 respectively on day 2 (P > 0.05), 0.58 ± 0.07 and 0.67 ± 0.09 respectively on day 3 (P > 0.05), and 0.71 ± 0.08 and 0.78 ± 0.06 respectively on day 4 (P > 0.05). Celecoxib induced proliferation inhibition and apoptosis by G₁-S cell cycle arrest: the percentage of QBC939 cells in G₀-G₁phase after treatment with 40 μmol/L (74.6 ± 66.21) and 20 μmol/L (68.63 ± 4.36) celecoxib increased significantly compared with control cells (54.41 ± 5.12, P < 0.01). The percentage of SK-CHA-1 cells in G₀-G₁ phase after treatment with various concentrations of celecoxib didn't change significantly compared with control cells. The TUNEL index was much higher in QBC939 cells treated with 20 μmol/L celecoxib for 2 d (0.063 ± 0.018) and for 4 d (0.102 ± 0.037) compared with control cells (0.017 ± 0.004, P < 0.01).

CONCLUSION: The current in vitro study indicates that inhibition of proliferation and induction of apoptosis in human cholangiocarcinoma cells by cyclooxygenase-2 specific inhibitor celecoxib may involve in COX-dependent mechanisms and PGE₂pathway. Celecoxib as a chemopreventive and chemotherapeutic agent might be effective primarily on COX-2-expressing cholangiocarcinoma.