Genetic mouse models as in vivo tools for cholangiocarcinoma research

Cholangiocarcinoma (CCA) is a genetically and histologically complex disease with a highly dismal prognosis. A deeper understanding of the underlying cellular and molecular mechanisms of human CCA will increase our current knowledge of the disease and expedite the eventual development of novel therapeutic strategies for this fatal cancer. This endeavor is effectively supported by genetic mouse models, which serve as sophisticated tools to systematically investigate CCA pathobiology and treatment response. These in vivo models feature many of the genetic alterations found in humans, recapitulate multiple hallmarks of cholangiocarcinogenesis (encompassing cell transformation, preneoplastic lesions, established tumors and metastatic disease) and provide an ideal experimental setting to study the interplay between tumor cells and the surrounding stroma. This review is intended to serve as a compendium of CCA mouse models, including traditional transgenic models but also genetically flexible approaches based on either the direct introduction of DNA into liver cells or transplantation of pre-malignant cells, and is meant as a resource for CCA researchers to aid in the selection of the most appropriate in vivo model system

Genetic mouse models as in vivo tools for cholangiocarcinoma research

Cholangiocarcinoma (CCA) is a genetically and histologically complex disease with a highly dismal prognosis. A deeper understanding of the underlying cellular and molecular mechanisms of human CCA will increase our current knowledge of the disease and expedite the eventual development of novel therapeutic strategies for this fatal cancer. This endeavor is effectively supported by genetic mouse models, which serve as sophisticated tools to systematically investigate CCA pathobiology and treatment response. These in vivo models feature many of the genetic alterations found in humans, recapitulate multiple hallmarks of cholangiocarcinogenesis (encompassing cell transformation, preneoplastic lesions, established tumors and metastatic disease) and provide an ideal experimental setting to study the interplay between tumor cells and the surrounding stroma. This review is intended to serve as a compendium of CCA mouse models, including traditional transgenic models but also genetically flexible approaches based on either the direct introduction of DNA into liver cells or transplantation of pre-malignant cells, and is meant as a resource for CCA researchers to aid in the selection of the most appropriate in vivo model system

Percutaneous Hepatic Perfusion (PHP) with Melphalan in Liver-Dominant Metastatic Uveal Melanoma: The German Experience

Percutaneous hepatic perfusion (PHP) delivers high-dose melphalan to the liver while minimizing systemic toxicity via filtration of the venous hepatic blood. This two-center study aimed to examine the safety, response to therapy, and survival of patients with hepatic-dominant metastatic uveal melanoma (UM) treated with PHP. A total of 66 patients with liver-dominant metastasized uveal melanoma, treated with 145 PHP between April 2014 and May 2020, were retrospectively analyzed with regard to adverse events (AEs; CTCAE v5.0), response (overall response rate (ORR)), and disease control rate (DCR) according to RECIST1.1, as well as progression-free and overall survival (PFS and OS). With an ORR of 59% and a DCR of 93.4%, the response was encouraging. After initial PHP, median hepatic PFS was 12.4 (confidence interval (CI) 4–18.4) months and median OS was 18.4 (CI 7–24.6) months. Hematologic toxicity was the most frequent AE (grade 3 or 4 thrombocytopenia after 24.8% of the procedures); less frequent was grade 3 or 4 hepatic toxicity (increased aspartate transaminase (AST) and alanine transaminase (ALT) after 7.6% and 6.9% of the interventions, respectively). Cardiovascular events included four cases of ischemic stroke (2.8%) and one patient with central pulmonary embolism (0.7%). In conclusion, PHP is a safe and effective salvage treatment for liver-dominant metastatic uveal melanoma. Serious AEs—though rare—demand careful patient selection

Experimental models to unravel the molecular pathogenesis, cell of origin and stem cell properties of cholangiocarcinoma

Human cholangiocarcinoma (CCA) is an aggressive tumour entity arising from the biliary tree, whose molecular pathogenesis remains largely undeciphered. Over the last decade, the advent of high-throughput and cell-based techniques has significantly increased our knowledge on the molecular mechanisms underlying this disease while, at the same time, unravelling CCA complexity. In particular, it becomes clear that CCA displays pronounced inter- and intra-tumoural heterogeneity, which is presumably the consequence of the interplay between distinct tissues and cells of origin, the underlying diseases, and the associated molecular alterations. To better characterize these events and to design novel and more effective therapeutic strategies, a number of CCA experimental and preclinical models have been developed and are currently generated. This review summarizes the current knowledge and understanding of these models, critically underlining their translational usefulness and limitations. Furthermore, this review aims to provide a comprehensive overview on cells of origin, cancers stem cells, and their dynamic interplay within CCA tissue. This article is protected by copyright. All rights reserved

Criteria for preclinical models of cholangiocarcinoma: scientific and medical relevance

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

Real-world data for Lenvatinib in hepatocellular carcinoma (ELEVATOR)

Background Lenvatinib is approved as first-line treatment for patients with advanced hepatocellular carcinoma (HCC). The efficacy of lenvatinib in Caucasian real-world patients is insufficiently defined. The purpose of this study was to evaluate the efficacy of lenvatinib in a multi-center cohort (ELEVATOR) from Germany and Austria. Methods A retrospective data analysis of 205 patients treated with first-line systemic lenvatinib at 14 different sites was conducted. Overall survival, progression free survival, overall response rate and adverse event rates were assessed and analyzed. Results Patients receiving lenvatinib in the real-world setting reached a median overall survival of 12.8 months, which was comparable to the results reported from the REFLECT study. Median overall survival (mOS) and progression free survival (mPFS) was superior in those patients who met the inclusion criteria of the REFLECT study compared to patients who failed to meet the inclusion criteria (mOS 15.6 vs 10.2 months, HR 0.55, 95% CI 0.38-0.81, p=0.002; mPFS 8.1 vs 4.8 months HR 0.65, 95% CI 0.46-0.91, p=0.0015). For patients with an impaired liver function according to the Albumin-Bilirubin (ALBI) grade, or reduced ECOG performance status $\geq$2, survival was significantly shorter compared to patients with sustained liver function (ALBI grade 1) and good performance status (ECOG performance status 0), respectively (HR 1.69, 95% CI 1.07-2.66, p=0.023; HR 2.25, 95% CI 1.19-4.23, p=0.012). Additionally, macrovascular invasion (HR 1.55, 95% CI 1.02-2.37, p=0.041) and an AFP $\geq$200 ng/mL (HR 1.56, 95% CI 1.03-2.34, p=0.034) were confirmed as independent negative prognostic factors in our cohort of patients with advanced HCC. Conclusion Overall, our data confirm the efficacy of lenvatinib as first-line treatment and did not reveal new or unexpected side effects in a large retrospective Caucasian real-world cohort, supporting the use of lenvatinib as meaningful alternative for patients that cannot be treated with IO-based combinations in first-line HCC