Liver Resection vs Nonsurgical Treatments for Patients With Early Multinodular Hepatocellular Carcinoma.

Importance: The 2022 Barcelona Clinic Liver Cancer algorithm currently discourages liver resection (LR) for patients with multinodular hepatocellular carcinoma (HCC) presenting with 2 or 3 nodules that are each 3 cm or smaller. Objective: To compare the efficacy of liver resection (LR), percutaneous radiofrequency ablation (PRFA), and transarterial chemoembolization (TACE) in patients with multinodular HCC. Design, Setting, and Participants: This cohort study is a retrospective analysis conducted using data from the HE.RC.O.LE.S register (n = 5331) for LR patients and the ITA.LI.CA database (n = 7056) for PRFA and TACE patients. A matching-adjusted indirect comparison (MAIC) method was applied to balance data and potential confounding factors between the 3 groups. Included were patients from multiple centers from 2008 to 2020; data were analyzed from January to December 2023. Interventions: LR, PRFA, or TACE. Main Outcomes and Measures: Survival rates at 1, 3, and 5 years were calculated. Cox MAIC-weighted multivariable analysis and competing risk analysis were used to assess outcomes. Results: A total of 720 patients with early multinodular HCC were included, 543 males (75.4%), 177 females (24.6%), and 350 individuals older than 70 years (48.6%). There were 296 patients in the LR group, 240 who underwent PRFA, and 184 who underwent TACE. After MAIC, LR exhibited 1-, 3-, and 5-year survival rates of 89.11%, 70.98%, and 56.44%, respectively. PRFA showed rates of 94.01%, 65.20%, and 39.93%, while TACE displayed rates of 90.88%, 48.95%, and 29.24%. Multivariable Cox survival analysis in the weighted population showed a survival benefit over alternative treatments (PRFA vs LR: hazard ratio [HR], 1.41; 95% CI, 1.07-1.86; P = .01; TACE vs LR: HR, 1.86; 95% CI, 1.29-2.68; P = .001). Competing risk analysis confirmed a lower risk of cancer-related death in LR compared with PRFA and TACE. Conclusions and Relevance: For patients with early multinodular HCC who are ineligible for transplant, LR should be prioritized as the primary therapeutic option, followed by PRFA and TACE when LR is not feasible. These findings provide valuable insights for clinical decision-making in this patient population.

Trends in liver transplantation for primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis is a cholestatic disease with a low prevalence in Italy. Indications for liver transplantation and the time of listing are not stated. AIM: We performed a national survey to investigate the listing criteria, comorbidities, and outcomes. METHODS: In April 2022, we surveyed liver transplantation in primary sclerosing cholangitis nationwide for the last 15 years. RESULTS: From 2007 to 2021, 445 patients were included on waiting lists, and 411 had undergone liver transplants. The median age at transplantation was 46 years (males 63.9%); 262 patients (59%) presented an inflammatory bowel disease. Transplants increased over the years, from 1.8 % in 2007 to 3.0 % in 2021. Cholangitis (51%) and hepatic decompensation (45%) were the main indications for listing. The disease recurred in 81 patients (20%). Patient survival after the first transplant was 94 %, 86% and 84% at one, five, and ten years. Twenty-four died in the first year (50% surgical complications, 25% infections); 33 between one to five years (36% recurrence, 21% cholangiocarcinoma recurrence) and nine after five years (56% de novo cancer, 44% recurrence). CONCLUSIONS: Primary sclerosing cholangitis has been an increasing indication for transplantation in Italy. Cholangitis and decompensation were the main indications for listing. Recurrence and cancer were the leading causes of death.

The Role of Transjugular Intrahepatic Portosystemic Shunt (TIPS) in Treating Portal Hypertension in Patients with Hepatocellular Carcinoma.

Liver cancer is very frequent, and hepatocellular carcinoma (HCC) accounts for the majority of liver cancer cases. Its growing incidence has been greatly affected by the increasing prevalence of metabolic-associated fatty liver disease (MAFLD). The latter is a new epidemic in our era. In fact, HCC is often generated from noncirrhotic liver and its treatment benefits from surgical and nonsurgical approaches, potentially bridged by transjugular intrahepatic portosystemic shunt (TIPS) use. TIPS use is an effective treatment for portal hypertension complications, but its application in patients with HCC and clinically significant portal hypertension (CSPH) remains controversial due to concerns about tumor rupture, dissemination, and increased toxicity. The technical feasibility and safety of TIPS use in HCC patients have been evaluated in several studies. Despite concerns about intraprocedural complications, retrospective studies have shown high success rates and low complication rates in TIPS placement for HCC patients. TIPS use in combination with locoregional treatments, such as transarterial chemoembolization (TACE) or transarterial radioembolization (TARE), has been explored as a treatment option for HCC patients with portal hypertension. These studies have shown improved survival rates in patients undergoing TIPS in combination with locoregional treatments. However, the efficacy and toxicity of TACE in combination with TIPS use require careful evaluation, as changes in venous and arterial flow can affect treatment outcomes and complications. The results from studies evaluating the impact of TIPS on systemic therapy and surgical options are also promising. In conclusion, the TIPS is a sufficiently safe, useful item available for physicians treating complications of portal hypertension. Moreover, a TIPS can be used in combination with locoregional therapy in HCC patients. Systemic chemotherapy can also benefit of the use of TIPS placement. A complex interplay affects TIPS use with surgery. The latter needs further data. The TIPS is a useful and safe add-on treatment, changing the natural course of HCC progression. Its use is regulated by a sophisticated physiologic and pathophysiologic flow of evidence.

Hepatectomy Versus Sorafenib in Advanced Nonmetastatic Hepatocellular Carcinoma: A Real-life Multicentric Weighted Comparison.

OBJECTIVE: The aim of the study was to compare SURG vs SOR regarding the OS and progression-free survival (PFS) in a real-world clinical scenario. BACKGROUND DATA: The treatment for advanced nonmetastatic HCC belonging to the Barcelona Clinic Liver Cancer stage C (BCLC C) is still controversial. METHODS: BCLC C patients without extrahepatic spread and tumoral invasion of the main portal trunk were considered. Surgical patients were obtained from the HE.RC.O.LE.S. Register, whereas sorafenib patients were obtained from the ITA.LI.CA register The inverse probability weighting (IPW) method was adopted to balance the confounders between the 2 groups. RESULTS: Between 2008 and 2019, 478 patients were enrolled: 303 in SURG and 175 in SOR group. Eastern Cooperative Oncological Group Performance Status (ECOG-PS), presence of cirrhosis, steatosis, Child-Pugh grade, hepatitis B virus and hepatitis C virus, alcohol intake, collateral veins, bilobar disease, localization of the tumor thrombus, number of nodules, alpha-fetoprotein, age, and Charlson Comorbidity index were weighted by IPW to create two balanced pseudo-populations: SURG = 374 and SOR = 263. After IPW, 1-3-5 years OS was 83.6%, 68.1%, 55.9% for SURG, and 42.3%, 17.8%, 12.8% for SOR (P < 0.001). Similar trends were observed after subgrouping patients by ECOG-PS = 0 and ECOG-PS >0, and by the intrahepatic location of portal vein invasion. At Cox regression, sorafenib treatment (hazard ratio 4.436; 95% confidence interval 3.19-6.15; P < 0.001) and Charlson Index (hazard ratio 1.162; 95% confidence interval 1.06-1.27; P = 0.010) were the only independent predictors of mortality. PFS at 1-3-5 years were 65.9%, 40.3%, 24.3% for SURG and 21.6%, 3.5%, 2.9% for SOR (P = 0.007). CONCLUSIONS: In BCLC C patients without extrahepatic spread but with intrahepatic portal invasion, liver resection, if feasible, was followed by better OS and PFS compared with sorafenib.

Comparison of prognostic models in advanced hepatocellular carcinoma patients undergoing Sorafenib: A multicenter study.

BACKGROUND: Sorafenib is the gold standard therapy for the advanced hepatocellular carcinoma (HCC). No scoring/staging is universally accepted to predict the survival of these patients. AIMS: To evaluate the accuracy of the available prognostic models for HCC to predict the survival of advanced HCC patients treated with Sorafenib included in the Italian Liver Cancer (ITA.LI.CA.) multicenter cohort. METHODS: The performance of several prognostic scores was assessed through a Cox regression-model evaluating the C-index and the Akaike Information Criterion (AIC). RESULTS: Data of 1129 patients were analyzed. The mean age of patients was 61.6 years, and 80.8% were male. During a median follow-up period of 13 months, 789 patients died. The median period of Sorafenib administration was 4 months. All the prognostic scores were able to predict the overall survival (p<0.001) at univariate analysis, except the Albumin-Bilirubin score. The Italian Liver Cancer score (CLIP) yielded the highest accuracy (C-index 0.604, AIC 9898), followed by the ITA.LI.CA. prognostic score (C-index 0.599, AIC 9915). CONCLUSIONS: The CLIP score had the highest accuracy in predicting the overall survival of HCC patients treated with Sorafenib, although its performance remained poor. Further studies are needed to refine the current ability to predict the outcome of HCC patients undergoing Sorafenib.

Correction: Application of the Intermediate-Stage Subclassification to Patients With Untreated Hepatocellular Carcinoma.

In the Italian Liver Cancer (ITA.LI.CA) Group, contributor name Alberta Capelli is misspelled and should be corrected to Alberta Cappelli.

Curative therapies are superior to standard of care (transarterial chemoembolization) for intermediate stage hepatocellular carcinoma.

BACKGROUND & AIMS: The Barcelona Clinic Liver Cancer intermediate stage (BCLC-B) of hepatocellular carcinoma (HCC) includes extremely heterogeneous patients in terms of tumour burden and liver function. Transarterial-chemoembolization (TACE) is the first-line treatment for these patients although it may be risky/useless for someone, while others could undergo curative treatments. This study assesses the treatment type performed in a large cohort of BCLC-B patients and its outcome. METHODS: Retrospective analysis of 485 consecutive BCLC-B patients from the ITA.LI.CA database diagnosed with naïve HCC after 1999. Patients were stratified by treatment. RESULTS: 29 patients (6%) were lost to follow-up before receiving treatment. Treatment distribution was: TACE (233, 51.1%), curative treatments (145 patients, 31.8%), sorafenib (18, 3.9%), other (39, 8.5%), best supportive care (BSC) (21, 4.6%). Median survival (95% CI) was 45 months (37.4-52.7) for curative treatments, 30 (24.7-35.3) for TACE, 14 (10.5-17.5) for sorafenib, 14 (5.2-22.7) for other treatments and 10 (6.0-14.2) for BSC (P<.0001). Independent prognosticators were gender and treatment. Curative treatments reduced mortality (HR 0.197, 95%CI: 0.098-0.395) more than TACE (HR 0.408, 95%CI: 0.211-0.789) (P<.0001) as compared with BSC. Propensity score matching confirmed the superiority of curative therapies over TACE. CONCLUSIONS: In everyday practice TACE represents the first-line therapy in an half of patients with naïve BCLC-B HCC since treatment choice is driven not only by liver function and nodule characteristics, but also by contraindications to procedures, comorbidities, age and patient opinion. The treatment type is an independent prognostic factor in BCLC-B patients and curative options offer the best outcome.

Application of the Intermediate-Stage Subclassification to Patients With Untreated Hepatocellular Carcinoma.

OBJECTIVES: The Barcelona Clinic Liver Cancer (BCLC) intermediate stage (BCLC B) includes a heterogeneous population of patients with hepatocellular carcinoma (HCC). Recently, in order to facilitate treatment decisions, a panel of experts proposed to subclassify BCLC B patients. In this study, we aimed to assess the prognostic capability of the BCLC B stage reclassification in a large cohort of patients with untreated HCC managed by the Italian Liver Cancer Group. METHODS: We assessed the prognosis of 269 untreated HCC patients observed in the period 1987-2012 who were reclassified according to the proposed subclassification of the BCLC B stage from stage B1 to stage B4. We evaluated and compared the survival of the various substages. RESULTS: Median survival progressively decreased from stage B1 (n=65, 24.2%: 25 months) through stages B2 (n=105, 39.0%: 16 months) and B3 (n=22, 8.2%: 9 months), to stage B4 (n=77, 28.6%: 5 months; P<0.0001). Moreover, we observed a significantly different survival between contiguous stages (B1 vs. B2, P=0.0002; B2 vs. B3, P<0.0001; B3 vs. B4, P=0.0219). In multivariate analysis, the BCLC B subclassification (P<0.0001), MELD score (P=0.0013), and platelet count (P=0.0252) were independent predictors of survival. CONCLUSIONS: The subclassification of the intermediate-stage HCC predicts the prognosis of patients with untreated HCC. The prognostic figures identified in this study may be used as a benchmark to assess the efficacy of therapeutic intervention in the various BCLC B substages, whereas it remains to be established whether incorporation of the MELD score might improve the prognosis of treated patients.

Prevalence and clinical outcome of hepatic haemangioma with specific reference to the risk of rupture: A large retrospective cross-sectional study.

BACKGROUND: Prevalence and incidence of hepatic haemangioma are estimated from autopsy series only. Although benign and generally asymptomatic, hepatic haemangioma can cause serious complications. AIMS: The aim of the study was to assess the prevalence of hepatic haemangioma and to attempt to quantify the risk of major complications such as spontaneous rupture. METHODS: We retrospectively analyzed the radiology database of a Regional University Hospital over a 7-year period: the radiological records of 83,181 patients who had an abdominal computed tomography or magnetic resonance scan were reviewed. Diagnoses made at imaging were reviewed and related to clinical course. RESULTS: Hepatic haemangioma was diagnosed in 2071 patients (2.5% prevalence). In 226 patients (10.9%), haemangioma had diameter of 4 cm or more (giant haemangioma). The risk of bleeding was assessed on patients without concomitant malignancies. Spontaneous bleeding occurred in 5/1067 patients (0.47%). All 5 patients had giant haemangioma: 4 had exophytic lesions and presented with haemoperitoneum; 1 with centrally located tumour experienced intrahepatic bleeding. CONCLUSION: Giant haemangiomas have a low but relevant risk of rupture (3.2% in this series), particularly when peripherally located and exophytic. Surgery might be considered in these cases.

PDX-1 mRNA expression in endoscopic ultrasound-guided fine needle cytoaspirate: perspectives in the diagnosis of pancreatic cancer.

BACKGROUND AND AIMS: Endoscopic ultrasound-guided fine needle aspiration is routinely used in the diagnostic work up of pancreatic cancer but has a low sensitivity. Studies showed that Pancreatic Duodenal Homeobox-1 (PDX-1) is expressed in pancreatic cancer, which is associated with a worse prognosis. We aimed to verify whether the assessment of PDX-1 in endoscopic ultrasound-guided fine needle aspiration samples may be helpful for the diagnosis of pancreatic cancer. METHODS: mRNA of 54 pancreatic cancer and 25 cystic lesions was extracted. PDX-1 expression was assessed by Real-Time PCR. RESULTS: In all but two patients with pancreatic cancer, PDX-1 was expressed and was found positive in 7 patients with pancreatic cancer in which cytology was negative. The positivity was associated with a probability of 0.98 (95% CI 0.90-1.00) of having cancer and the negativity with one of 0.08 (95% CI 0.01-0.27). The probability of cancer rose to 1.00 (95% CI 0.97-1.00) for patients positive to both PDX-1 and cytology and fell to 0.0 (95% CI 0.00-0.15) in patients negative for both. CONCLUSIONS: PDX-1mRNA is detectable in samples of pancreatic cancer. Its quantification may be helpful to improve the diagnosis of pancreatic cancer.

Activation of the developmental pathway neurogenin-3/microRNA-7a regulates cholangiocyte proliferation in response to injury.

UNLABELLED: The activation of the biliary stem-cell signaling pathway hairy and enhancer of split 1/pancreatic duodenal homeobox-1 (Hes-1/PDX-1) in mature cholangiocytes determines cell proliferation. Neurogenin-3 (Ngn-3) is required for pancreas development and ductal cell neogenesis. PDX-1-dependent activation of Ngn-3 initiates the differentiation program by inducing microRNA (miR)-7 expression. Here we investigated the role Ngn-3 on cholangiocyte proliferation. Expression levels of Ngn-3 and miR-7 isoforms were tested in cholangiocytes from normal and cholestatic human livers. Ngn-3 was knocked-down in vitro in normal rat cholangiocytes by short interfering RNA (siRNA). In vivo, wild-type and Ngn-3-heterozygous (+/-) mice were subjected to 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) feeding (a model of sclerosing cholangitis) or bile duct ligation (BDL). In the liver, Ngn-3 is expressed specifically in cholangiocytes of primary sclerosing cholangitis (PSC) patients and in mice subjected to DDC or BDL, but not in normal human and mouse livers. Expression of miR-7a-1 and miR-7a-2 isoforms, but not miR-7b, was increased in DDC cholangiocytes compared to normal ones. In normal rat cholangiocytes, siRNA against Ngn-3 blocked the proliferation stimulated by exendin-4. In addition, Ngn-3 knockdown neutralized the overexpression of insulin growth factor-1 (IGF1; promitotic effector) observed after exposure to exendin-4, but not that of PDX-1 or VEGF-A/C. Oligonucleotides anti-miR-7 inhibited the exendin-4-induced proliferation in normal rat cholangiocytes, but did not affect Ngn-3 synthesis. Biliary hyperplasia and collagen deposition induced by DDC or BDL were significantly reduced in Ngn-3(+/-) mice compared to wild-type. CONCLUSION: Ngn-3-dependent activation of miR-7a is a determinant of cholangiocyte proliferation. These findings indicate that the reacquisition of a molecular profile typical of organ development is essential for the biological response to injury by mature cholangiocytes.

Estimation of lead-time bias and its impact on the outcome of surveillance for the early diagnosis of hepatocellular carcinoma.

BACKGROUND & AIMS: Lead-time is the time by which diagnosis is anticipated by screening/surveillance with respect to the symptomatic detection of a disease. Any screening program, including surveillance for hepatocellular carcinoma (HCC), is subject to lead-time bias. Data regarding lead-time for HCC are lacking. Aims of the present study were to calculate lead-time and to assess its impact on the benefit obtainable from the surveillance of cirrhotic patients. METHODS: One-thousand three-hundred and eighty Child-Pugh class A/B patients from the ITA.LI.CA database, in whom HCC was detected during semiannual surveillance (n = 850), annual surveillance (n = 234) or when patients came when symptomatic (n = 296), were selected. Lead-time was estimated by means of appropriate formulas and Monte Carlo simulation, including 1000 patients for each arm. RESULTS: The 5-year overall survival after HCC diagnosis was 32.7% in semiannually surveilled patients, 25.2% in annually surveilled patients, and 12.2% in symptomatic patients (p<0.001). In a 10-year follow-up perspective, the median lead-time calculated for all surveilled patients was 6.5 months (7.2 for semiannual and 4.1 for annual surveillance). Lead-time bias accounted for most of the surveillance benefit until the third year of follow-up after HCC diagnosis. However, even after lead-time adjustment, semiannual surveillance maintained a survival benefit over symptomatic diagnosis (number of patients needed to screen = 13), as did annual surveillance (18 patients). CONCLUSIONS: Lead-time bias is the main determinant of the short-term benefit provided by surveillance for HCC, but this benefit becomes factual in a long-term perspective, confirming the clinical utility of an anticipated diagnosis of HCC.

Rise and fall of HCV-related hepatocellular carcinoma in Italy: a long-term survey from the ITA.LI.CA centres.

BACKGROUND & AIMS: Hepatitis C virus (HCV) is the leading aetiological factor of HCC in the western world where, overall, its incidence is increasing, despite data suggesting an initial drop in some areas. The aim of this study was to evaluate epidemiology, clinical features and survival of HCV-related HCC (HCV-HCC) in a wide time range in Italy. METHODS: Multicentre retrospective study including 3695 patients prospectively recruited by the ITA.LI.CA group. Patients were classified into three subgroups according to aetiology (Group A[GA], pure HCV; Group B[GB], HCV + cofactors; and Group C[GC], non-HCV) and in 5 time cohorts (5 years each), according to the year of diagnosis. Age, gender, Child-Pugh score, modality of diagnosis, stage, presence of thrombosis/metastases, type of treatment and survival were analysed. RESULTS: A total of 1801 GA patients, 445 GB and 1333 GC were recruited. The number of GA patients peaked in the 1996-2000, gradually dropping thereafter (P < 0.0001), as observed for GB (P < 0.0001). Age at diagnosis increased (P < 0.0001), while percentage of patients diagnosed during surveillance and stage improved only in GA (P = 0.02 and P = 0.003 respectively). The survival significantly increased over time particularly in GA (median 37 months) and was longer in GA than in GB and GC (P < 0.0001). CONCLUSIONS: The prevalence of HCC-HCV is decreasing in Italy since 2001. HCV-HCC patients are older, more frequently diagnosed under surveillance and in an earlier stage. HCC survival improved in the last 15 years and is significantly higher in patients with HCV-HCC. We therefore expect a further drop in both incidence and mortality for HCV-HCC in the years to come.

Liver carcinogenesis: rodent models of hepatocarcinoma and cholangiocarcinoma.

Hepatocellular carcinoma and cholangiocarcinoma are primary liver cancers, both represent a growing challenge for clinicians due to their increasing morbidity and mortality. In the last few years a number of in vivo models of hepatocellular carcinoma and cholangiocarcinoma have been developed. The study of these models is providing a significant contribution in unveiling the pathophysiology of primary liver malignancies. They are also fundamental tools to evaluate newly designed molecules to be tested as new potential therapeutic agents in a pre-clinical set. Technical aspects of each model are critical steps, and they should always be considered in order to appropriately interpret the findings of a study or its planning. The purpose of this review is to describe the technical and experimental features of the most significant rodent models, highlighting similarities or differences between the corresponding human diseases. The first part is dedicated to the discussion of models of hepatocellular carcinoma, developed using toxic agents, or through dietary or genetic manipulations. In the second we will address models of cholangiocarcinoma developed in rats or mice by toxin administration, genetic manipulation and/or bile duct incannulation or surgery. Xenograft or syngenic models are also proposed.

Trans-arterial chemo-embolization (TACE), with either lipiodol (traditional TACE) or drug-eluting microspheres (precision TACE, pTACE) in the treatment of hepatocellular carcinoma: efficacy and safety results from a large mono-institutional analysis.

More data about TACE and pTACE seem necessary to better define the global treatment strategy for HCC. Aim of our analysis was to evaluate the role of TACE, either with lipiodol (traditional) or drug-eluting microspheres in terms of response rate (RR), time to progression (TTP), overall survival (OS) and toxicity in HCC.Patients with HCC undergoing traditional TACE or pTACE (either alone or in combination with other treatment options) were eligibleOne hundred and fifty patients were analyzed. In the global patient population median OS was 46 months for lipiodol TACE and 19 months for pTACE (p < 0.0001), TTP was 30 months versus 16 months for patients receiving TACE or pTACE respectively (p = 0.003). These results were confirmed also among the group of patients who received exclusive TACE or pTACE. Neither RR nor toxicity was different between TACE or pTACE.At multivariate analysis, age, the Okuda stage, type of TACE and number of TACE proved to be independent prognostic factors influencing overall survival.In our experience, lipiodol TACE showed a better OS and TTP over pTACE, without difference in toxicity profile and RR. Among the staging systems analyzed only the Okuda stage seemed able to reliably predict patients outcome.

Cell proliferation and drug resistance in hepatocellular carcinoma are modulated by Rho GTPase signals.

Hepatocellular carcinoma is highly resistant to chemotherapeutic agents, thus the need to discover effective therapeutic molecules to suppress cancer cell growth and to overcome drug resistance is urgent. The Rho GTPase is implicated in cancer and metastasis and is directly activated by the Lymphoid blast crisis (Lbc) protooncogene, a Rho guanine-nucleotide exchange factor. The aim of the study was to analyze the expression of Lbc in hepatocarcinoma and to determine the effect of Lbc-induced Rho signaling on expression, growth rate and resistance to genotoxic stress. We found, by immunohistochemical analysis of biopsy samples and Northern and Western blot analyses of cell lines, that Lbc is absent in normal adult liver but is abundantly expressed in hepatocarcinoma, implying an increased Rho pathway signaling. Lbc stably transfected hepatocarcinoma cells exhibit increased proliferation and levels of ERK and cyclin D1 activation, which are blocked by a Rho inhibitor. In contrast, AKT activation was not altered. Moreover, Lbc expression confers increased resistance to genotoxic stress induced by doxorubicin, which is associated with upregulation of Bcl-2 and BAD phosphorylation, and this is reversed by a Rho inhibitor. In conclusion, these data support a role for Rho in liver cancer progression and resistance to therapy and may provide a basis for developing effective treatment for hepatocarcinoma.

Nerve growth factor modulates the proliferative capacity of the intrahepatic biliary epithelium in experimental cholestasis.

BACKGROUND & AIMS: We evaluated the expression of neurotrophins in rat cholangiocytes and the role and mechanisms by which nerve growth factor (NGF) modulates cholangiocyte proliferation. METHODS: The expression of neurotrophins and their receptors was investigated by immunohistochemistry in liver sections and reverse-transcription polymerase chain reaction and immunoblots in isolated cholangiocytes. In vitro, the effect of NGF on cholangiocyte proliferation and signal transduction was investigated by immunoblotting for proliferating cell nuclear antigen, phosphorylated AKT (p-AKT), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), phosphorylated c-jun-N-terminal kinase, and phosphorylated p38. In vivo, rats that had undergone bile duct ligation (BDL) were treated with an anti-NGF antibody to immunoneutralize NGF and bile duct mass, proliferation, apoptosis, and inflammation were investigated by immunohistochemistry. RESULTS: NGF and its TrkA receptor were expressed by normal rat cholangiocytes and up-regulated following BDL. Cholangiocytes secrete NGF, and secretion is increased in proliferating BDL cholangiocytes. In vitro, NGF stimulated cholangiocyte proliferation, which was associated with enhanced p-AKT and p-ERK1/2 expression. NGF proliferation in vitro was partially blocked by the MEK inhibitor (UO126) and completely ablated by the phosphatidylinositol 3-kinase inhibitor (wortmannin). In vitro, NGF and estrogens have an additive effect on cholangiocyte proliferation by acting on phosphorylated TrkA and p-ERK1/2. In vivo, immunoneutralization of NGF decreased bile duct mass in BDL rats, which was associated with depressed proliferation and enhanced apoptosis and with increased portal inflammation. CONCLUSIONS: Cholangiocytes secrete NGF and express NGF receptors. NGF induces cholangiocyte proliferation by activating the ERK and, predominantly, the phosphatidylinositol 3-kinase pathway and exerts an additive effect in combination with estrogens on proliferation.