Report of a multicenter phase II trial testing a combination of biweekly bevacizumab and daily erlotinib in patients with unresectable biliary cancer: a phase II Consortium study

Overview of current targeted therapy in gallbladder cancer

Gallbladder cancer (GBC) is rare, but is the most malignant type of biliary tract tumor. Unfortunately, only a small population of cancer patients is acceptable for the surgical resection, the current effective regimen; thus, the high mortality rate has been static for decades. To substantially circumvent the stagnant scenario, a number of therapeutic approaches owing to the creation of advanced technologic measures (e.g., next-generation sequencing, transcriptomics, proteomics) have been intensively innovated, which include targeted therapy, immunotherapy, and nanoparticle-based delivery systems. In the current review, we primarily focus on the targeted therapy capable of specifically inhibiting individual key molecules that govern aberrant signaling cascades in GBC. Global clinical trials of targeted therapy in GBC are updated and may offer great value for novel pathologic and therapeutic insights of this deadly disease, ultimately improving the efficacy of treatment.

Systemic treatment options for advanced biliary tract carcinoma

Advanced biliary tract cancers (BTC) include a diverse collection of rare and heterogenous tumors with poor prognosis. The combination of gemcitabine and cisplatin is the established first-line therapy for advanced BTC. There are no accepted standard treatments in the second line setting, though there are several ongoing clinical trials that implement chemotherapy as a therapeutic strategy. The understanding of the molecular landscape of BTC has offered hope of targeted therapies to the identified actionable genomic aberrations, such as FGFR2 gene fusions, mutations of IDH1/2, HER2, BRAC1/2 and BRAF. Pembigatinib has become the first approved targeted therapy for BTC with FGFR2 fusion or other rearrangements. Recent immunotherapy has opened new therapy avenues in BTC with pembrolizumab approved for either microsatellite instability high (MSI-H) or DNA mismatch repair deficient (dMMR) advanced solid tumors, including BTC. The combination of immunotherapy with other modalities is currently being evaluated in different clinical trials, since single agent immunotherapy appears to provide modest benefits in advanced BTC. In this review, we summarize the current status of treatment options, including systemic chemotherapy, targeted therapy, immunotherapy, and various combinations in advanced BTC.

Cholangiocarcinoma: investigations into pathway-targeted therapies

INTRODUCTION

Cholangiocarcinoma is a malignant disease of the biliary tract and accounts for 3% of all gastrointestinal tumors. Surgical intervention is currently the only potentially curative strategy for cholangiocarcinoma. For patients with unresectable, advanced or metastatic disease, the combination of gemcitabine with cisplatin is considered the standard treatment. However, currently available therapeutic options have only a marginal benefit, especially among patients with relapsed/refractory tumors.

AREAS COVERED

We reviewed targeted agents under clinical evaluation for patients with cholangiocarcinoma. FGFR and IDH inhibitors are at the most advanced stage of clinical investigation. EGFR inhibitors have demonstrated contradictory results, whereas inhibition of other molecular pathways, including the RAS/RAF/MEK/ERK, the MET, the PI3K/AKT/mTOR and angiogenetic pathways, has shown minimal or null benefit.

EXPERT OPINION

Several targeted approaches are being investigated for advanced cholangiocarcinoma. However, randomized clinical trials are needed to define the optimal treatment regimen and address issues including the option of monotherapy or combination regimens, the optimal sequence of different treatments, ways to overcome resistance to targeted treatments, as well as determining the right time and tissue for assessing molecular signatures. Targeted therapies and immunotherapy hold promise for improving patient outcomes in the future.

Emerging pathways for precision medicine in management of cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common biliary tract malignancy with a dismal prognosis. Surgical resection with a negative microscopic margin offers the only hope for long-term survival. However, the majority of patients present with advanced disease not amenable to curative resection, mainly due to late presentation and aggressive nature of the disease. Unfortunately, due to the heterogeneous nature of CCA as well as limitations of available chemotherapy medications, traditional chemotherapy regimens offer limited survival benefit. Recent advances in genomic studies and next-generation sequencing techniques have assisted in better understanding of cholangiocarcinogenesis and identification of potential aberrant signaling pathways. Targeting the specific genomic abnormalities via novel molecular therapies has opened a new avenue in management of CCA with encouraging results in preclinical studies and early clinical trials. In this review, we present emerging therapies for precision medicine in CCA.

ErBb Family Proteins in Cholangiocarcinoma and Clinical Implications

The erythroblastic leukemia viral oncogene homolog (ErBb) family consists of the receptor tyrosine kinases (RTK) epidermal growth factor receptor (EGFR; also called ERBB1), ERBB2, ERBB3, and ERBB4. This family is closely associated with the progression of cholangiocarcinoma (CC) through the regulation of cellular networks, which are enhanced during tumorigenesis, metastasis, and chemoresistance. Additionally, the constitutive activation of cellular signaling by the overexpression and somatic mutation-mediated alterations conferred by the ErBb family on cholangiocarcinoma and other cancers enhances tumor aggressiveness and chemoresistance by contributing to the tumor microenvironment. This review summarizes the recent findings on the molecular functions of the ErBb family and their mutations during the progression of cholangiocarcinoma. It also discusses the developments and applications of various devising strategies for targeting the ErBb family through different inhibitors in various stages of clinical trials, which are essential for improving targeted clinical therapies.

Targets for therapy in biliary tract cancers: the new horizon of personalized medicine

Biliary tract cancers (BTCs) are a set of molecularly distinct and heterogeneous diseases. While cytotoxic chemotherapy remains the current standard of care for treatment-naïve and treatment-refractory unresectable disease, recently identified mutations driving oncologic development offer opportunities for targeted therapy. Currently, alterations in the fibroblast growth factor receptor (FGFR), isocitrate dehydrogenase (IDH), v-Raf murine sarcoma viral oncogene homolog B (BRAF), DNA damage repair, and HER2 pathways have demonstrated promising new therapeutic avenues, among others, and various studies have demonstrated clinical activity with targeted tyrosine kinase inhibitors and/or antibodies. In this review, we will discuss the currently identified targets for therapy in BTCs and review currently available data regarding clinical development of treatment options in these molecularly distinct subsets.

Clinical and Translational Research Challenges in Biliary Tract Cancers

BACKGROUND

Biliary Tract Cancers (BTC) are rare malignancies with a poor prognosis. There are many challenges encountered in treating these patients in daily practice as well as in clinical, translational and basic research.

OBJECTIVE

This review summarises the most relevant challenges in clinical and translational research in BTCs and suggests potential solutions towards an improvement in quality of life and outcomes of patients diagnosed with such malignancies.

FINDINGS

The main challenge is the low number of patients with BTCs, complicated by the aggressive natural behaviour of cancer and the lack of funding sources for research. In addition, the clinical characteristics of these patients and the specific cancer-related complications challenge clinical research and clinical trial recruitment. It is worth highlighting that BTCs are a group of different malignancies (cholangiocarcinoma, gallbladder cancer and ampullary cancer) rather than a unique homogeneous disease. These subgroups differ not only in molecular aspects, but also in clinical and demographic characteristics. In addition, tailored imaging and quality of life assessment are required to tackle some of the issues specific to BTCs. Finally, difficulties in tissue acquisition both in terms of biopsy size and inclusion of sufficient tumour within the samples, may adversely impact translational and basic research.

CONCLUSION

Increasing awareness among patients and clinicians regarding BTC and the need for further research and treatment development may address some of the main challenges in BTC research. International collaboration is mandatory to progress the field.

Remarkable Response of Metastatic Gallbladder Carcinoma to Apatinib After Failed Multiline Chemotherapies: A Case Report and Literature Review

Gallbladder carcinoma (GBC) is a relatively rare and aggressive malignant tumor with a poor prognosis. A systematic review of current clinical studies illustrates an extreme paucity of second-line therapeutic options following the failure of standard-of-care cisplatin-gemcitabine chemotherapy. The efficacy of apatinib, an highly potent and selective oral inhibitor of VEGFR-2 tyrosine kinase, for refractory advanced GBC has not yet been clarified. Herein, we report a case of advanced GBC that presented a durable partial response to apatinib used as monotherapy after the failure of multiline chemotherapies including S-1 monotherapy, capecitabine monotherapy, gemcitabine plus capecitabine, and irinotecan plus oxaliplatin. The patient achieved an efficacy of partial response within 2 months. By September 23, 2019, the duration of treatment had extended for almost 1 year with a satisfactory quality of life, and the administration of apatinib was continued. Dose reduction of apatinib occurred at week four due to grade 2 hypertension and hand-foot skin reaction (HFSR). No fatigue, proteinuria, mucositis, or thrombocytopenia occurred. To the best of our knowledge, this is the first case of a successful use of apatinib monotherapy for heavily pretreated GBC. Further prospective studies are warranted to confirm the efficacy and safety of apatinib in GBC.

Mitogen-Activated Protein Kinases (MAPKs) and Cholangiocarcinoma: The Missing Link

In recent years, the incidence of both liver and biliary tract cancer has increased. Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) are the two most common types of hepatic malignancies. Whereas HCC is the fifth most common malignant tumor in Western countries, the prevalence of CCA has taken an alarming increase from 0.3 to 2.1 cases per 100,000 people. The lack of specific biomarkers makes diagnosis very difficult in the early stages of this fatal cancer. Thus, the prognosis of CCA is dismal and surgery is the only effective treatment, whilst recurrence after resection is common. Even though chemotherapy and radiotherapy may prolong survival in patients with CCA, the 5-year survival rate is still very low—a significant global problem in clinical diagnosis and therapy. The mitogen-activated protein kinase (MAPK) pathway plays an important role in signal transduction by converting extracellular stimuli into a wide range of cellular responses including inflammatory response, stress response, differentiation, survival, and tumorigenesis. Dysregulation of the MAPK cascade involves key signaling components and phosphorylation events that play an important role in tumorigenesis. In this review, we discuss the pathophysiological role of MAPK, current therapeutic options, and the current situation of MAPK-targeted therapies in CCA.

Advances in the Diagnosis and Treatment of Patients with Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is an aggressive biliary tract cancer (BTC) that arises from the biliary tract epithelium distal to the secondary biliary radicals. Over the past decade, significant advances have been made in the diagnosis, staging, and treatment of ICC. Emerging data have highlighted the importance of lymphadenectomy for elucidating patient prognosis as well as the at-risk nodal basins based on tumor location (de Jong et al. in J Clin Oncol 29(23):3140-3145, 2011). Several large randomized controlled trials have recently been published clarifying the role of adjuvant therapy for BTCs (Cloyd and Pawlik in J Oncol Pract 14(12):723-724, 2018). In addition, the molecular understanding of ICC pathogenesis has increased over time, leading to new potential molecular biomarkers and opening opportunities for novel targeted and immunologic therapies (Rizvi et al. in Nat Rev Clin Oncol 15(2):95-111, 2018). These recent advances serve to only improve our understanding of the optimal multidisciplinary treatment of this difficult disease.

Biliary tract cancer prognostic and predictive genomics

Biliary tract cancer (BTC) is comprised of intrahepatic cholangiocarcinoma (ICC), extrahepatic cholangiocarcinoma (EHC) and gallbladder cancer (GBC). These tumors arise in the biliary epithelium, share histological characteristics and are associated with grim prognosis even when diagnosed at early stages. Moreover, its relatively low incidence in developed countries has precluded the development of clinical trials addressing specific differences among BTC subgroups in terms of their biology, treatment response and clinical outcomes. In this scenario, the development of effective treatment strategies for patients has been rather modest. To date, the combination of cisplatin plus gemcitabine remains as the standard first line therapy in advanced disease and after progression to this regimen there are limited treatment options. Next generation sequencing (NGS) studies have assessed the distribution of driver genes and potentially actionable genomic alterations among ICC, EHC and GBC. Here, we outline genomic differences among these subsets and describe key milestones in order to develop novel targeted drugs against BTCs. Although the early results of several studies are promising, international collaboration is critical to conduct adequately-powered trials, enrolling patients from high-incidence countries.

Diagnostic-therapeutic management of bile duct cancer

Biliary tract cancer, or cholangiocarcinoma, comprises a heterogeneous group of malignant tumors that can emerge at any part of the biliary tree. This group is the second most common type of primary liver cancer. Diagnosis is usually based on symptoms, which may be heterogeneous, and nonspecific biomarkers in serum and biopsy specimens, as well as on imaging techniques. Endoscopy-based diagnosis is essential, since it enables biopsy specimens to be taken. In addition, it can help with locoregional staging of distal tumors. Endoscopic retrograde cholangiopancreatography is a key technique for the evaluation and treatment of malignant biliary tumors. Correct staging of cholangiocarcinoma is essential in order to be able to determine the degree of resectability and assess the results of treatment. The tumor is staged based on the TNM classification of the American Joint Committee on Cancer. The approach will depend on the classification of the tumor. Thus, some patients with early-stage disease could benefit from surgery; complete surgical resection is the cornerstone of cure. However, only a minority of patients are diagnosed in the early stages and are suitable candidates for resection. In the subset of patients diagnosed with locally advanced or metastatic disease, chemotherapy has been used to improve outcome and to delay tumor progression. The approach to biliary tract tumors should be multidisciplinary, involving experienced endoscopists, oncologists, radiologists, and surgeons.

Molecular pathogenesis of gallbladder cancer: An update

Gallbladder carcinoma (GBC) is the most aggressive gastrointestinal malignancy throughout the world, with wide geographical variance. It is the subtype of biliary tract malignancy that has the poorest prognosis and lower survival among all biliary tract malignancies. Various factors are associated with GBC pathogenesis such as environmental, microbial, metabolic and molecular. Chronic inflammation of gallbladder due to presence of gallstone or microbial infection (eg. Salmonella or H. pylori) results in sustained production of inflammatory mediators in the tissue microenvironment, which can cause genomic changes linked to carcinogenesis. Genetic alterations are one of the major factors, associated with aggressiveness and prognosis. Researches have been done to explore suitable biomarker for early diagnosis and identify altered molecular pathways to develop appropriate biomarkers for early diagnosis, therapy and predicting prognosis. Different agents for targeted therapy against actionable mutations of molecules like EGFR, VEGF, mTOR, HER2, PDL-1, PD-1, MET, PI3K, N-cadherin, VEGFR, MEK1 and MEK2 are being tried. Despite these advancements, there is dismal improvement in the survival of GBC patients. Genetic aberrations other than actionable mutations and epigenetic modification including aberrant expressions of micro-RNAs, are also being studied both as diagnostic biomarker and therapeutic targets. Complex pathogenesis of GBC still needs to be unfolded. In this review we focus on the molecular pathogenesis of GBC elucidated till date along with future directions that can be explored to achieve better management of GBC patients.

A Phase I Trial of the VEGF Receptor Tyrosine Kinase Inhibitor Pazopanib in Combination with the MEK Inhibitor Trametinib in Advanced Solid Tumors and Differentiated Thyroid Cancers

PURPOSE

Differentiated thyroid cancer (DTC) responds to VEGF receptor inhibitors. VEGF signals through RAS/RAF/MEK signaling. We evaluated the safety and efficacy of the VEGF receptor inhibitor pazopanib and MEK inhibitor trametinib in advanced solid tumors and DTC.

PATIENTS AND METHODS

Patients with advanced solid tumors were enrolled in a phase I, multicenter trial with a DTC expansion cohort. Patients received pazopanib 400-800 mg and trametinib 1-2 mg daily. Efficacy in the expansion cohort was assessed with objective response (OR) at 6 months of treatment.

RESULTS

Twenty-six patients were enrolled in five dose levels. MTD was not reached; the recommended phase II dose was pazopanib 800 mg orally and trametinib 2 mg orally every day. There was one dose-limiting toxicity on dose level 1 with grade 3 fatigue and muscle weakness. Common grade 3 adverse events were elevated transaminases (19%), diarrhea (15%), hypertension (12%), and fatigue (8%). Thirteen patients were enrolled in the DTC cohort; OR was 33% (95% confidence interval, 9.9, 65.1%) and median progression-free survival was 10.7 months. The cohort was terminated after planned interim analysis suggested insufficiently increased activity against the historical control of pazopanib alone. Reduction in tumor diameter negatively correlated with p-ERK change in tumor (Spearman ρ = -0.71; P = 0.05). NRAS mutation was associated with response (Fisher exact P = 0.008).

CONCLUSIONS

Pazopanib + trametinib was tolerable at full single-agent doses with clinical activity in DTC but did not achieve the prespecified response rate target.

Medical treatment for cholangiocarcinoma

Most of the patients with cholangiocarcinoma (CCA) present with advanced (inoperable or metastatic) disease, and relapse rates are high in those undergoing potentially curative resection. Previous treatment nihilism of patients with advanced disease has been replaced by active clinical research with the advent of randomized clinical trials (RCTs) and a much greater effort at understanding molecular mechanisms underpinning CCA. Three RCTs have recently been reported evaluating adjuvant chemotherapy following curative resection; only one of these has the potential to change practice. The BILCAP study failed to meet its primary endpoint by intention-to-treat analysis; however, a survival benefit was seen in a preplanned sensitivity analysis (predominantly adjusting for lymph nodes status). This, along with the numerical difference in median overall survival has led to the uptake of adjuvant capecitabine by many clinicians. In patients with advanced disease, the only level 1 data available supports the use of cisplatin and gemcitabine for the first-line treatment of patients with advanced disease; there is no established second-line chemotherapy. Previous forays into targeted therapy have proven unfruitful (namely targeting the epithelial growth factor receptor and vascular endothelial growth factor pathways). An increasing number of genomic subtypes are being defined; for some of these on-target therapeutic options are under active investigation. The most developed are studies targeting IDH-1 (isocitrate dehydrogenase) mutations and FGFR-2 (fibroblast growth factor receptor) fusions, with promising early results. Several other pathways are under evaluation, along with early studies targeting the immune environment; these are too premature to change practice to date. These emerging treatments are discussed.

Cholangiocarcinoma: the quest for a second-line systemic treatment

Biliary tract cancers (BTC) are a heterogeneous group of epithelial neoplasms, with a poor prognosis. Advanced BTC remains a challenging, non-curable disease. Gemcitabine plus platinum chemotherapy is the standard of care as first-line (L1) therapy in this setting. Beyond failure of L1, available evidence to guide therapeutic decisions is scarce. Data from phase III studies are lacking and there is no validated strategy to date. In this review, we provide an overview of the systemic therapeutic options that can be proposed and unsolved questions in the management of patients with advanced BTC in the second-line (L2) setting. Criteria to select which patients should receive L2 therapy are ill defined and reliable prognostic tools and models to help estimate individual patient survival at the beginning of L2 are needed. Chemotherapy, mainly fluoropyrimidine-based yields modest survival results. There is insufficient evidence level to recommend a specific L2 chemotherapy regimen, and anti-epidermal growth factor receptor and antiangiogenic agents failed to demonstrate any survival improvement in a non-selected patient population. In recent years, knowledge about BTC molecular heterogeneity has considerably increased with the advent of high-throughput genomic and transcriptomic analyses, opening new avenues for targeted therapies. Patients with BTC may be particularly good candidates for biomarker-driven therapy in clinical practice. Among the ongoing developments, targeting of FGFR and IDH mutations and immune therapies hold many promises for the next future. In future L2 clinical trials, patients should be carefully characterized and stratified according to prognostic factors, disease subtype, and genetic drivers.

FOLFIRI as second-line treatment of metastatic biliary tract cancer patients

The combination of cisplatin and gemcitabine is the standard first-line treatment of metastatic biliary tract cancer (BTC) patients. The benefit of second-line chemotherapy in these patients is controversial. This study aims to evaluate the activity of FOLFIRI (fluorouracil and irinotecan) after failure to the first-line platinum and gemcitabine-based chemotherapy in metastatic BTC patients. We present a single-institution, retrospective cohort study. Patients with locally advanced or metastatic BTC who progressed after at least one line of chemotherapy, consecutively treated at our Institution between 2007 and 2017 were included. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were overall survival (OS), clinical benefit rate (CBR) and safety profile of FOLFIRI. Twelve patients were included in the analysis, with a median follow up of 5 months (95% CI 2.77-7.20). The median number of cycles received was 3 (range 1 to 9). Four grade 3 toxicities were recorded; no grade 4 toxicities and no treatment-related deaths occurred. The median PFS was 1.7 months (95% CI; 0.66-2.67), and median OS was 5 months (95% CI; 2.77-7.20). Two patients presented stable disease, providing a CBR of 17%. We concluded that FOLFIRI presented a favorable toxicity profile and a modest activity in metastatic BTC patients who had progressed to platinum and gemcitabine and may be considered in patients who are able to tolerate additional lines of chemotherapy. Immunotherapy and targeted therapies selected according to the tumoral genomic profile are promising alternatives to improve the outcomes of second-line treatment in BTC.

Gallbladder Cancer: Diagnosis, Surgical Management, and Adjuvant Therapies

Gallbladder cancer (GBC) is an often lethal disease, but surgical resection is potentially curative. Symptoms may be misdiagnosed as biliary colic; over half of new diagnoses are made after laparoscopic cholecystectomy for presumed benign disease. Gallbladder polyps >1 cm should prompt additional imaging and cholecystectomy. For GBC diagnosed after cholecystectomy, tumors T1b and greater necessitate radical cholecystectomy. Radical cholecystectomy includes staging laparoscopy, hepatic resection, and locoregional lymph node clearance to achieve R0 resection. Patients with locally advanced disease (T3 or T4), hepatic-sided T2 tumors, node positivity, or R1 resection may benefit from adjuvant chemotherapy. Chemotherapy increases survival in unresectable disease.

Targeted Therapies in Cholangiocarcinoma: Emerging Evidence from Clinical Trials

Cholangiocarcinoma (CCA) is a highly-aggressive malignancy arising from the biliary tree, characterized by a steady increase in incidence globally and a high mortality rate. Most CCAs are diagnosed in the advanced and metastatic phases of the disease, due to the paucity of signs and symptoms in the early stages. This fact, along with the poor results of the local and systemic therapies currently employed, is responsible for the poor outcome of CCA patients and strongly supports the need for novel therapeutic agents and strategies. In recent years, the introduction of next-generation sequencing technologies has opened new horizons for a better understanding of the genetic pathophysiology of CCA and, consequently, for the identification and evaluation of new treatments tailored to the molecular features or alterations progressively elucidated. In this review article, we describe the potential targets under investigation and the current molecular therapies employed in biliary tract cancers. In addition, we summarize the main drugs against CCA under evaluation in ongoing trials and describe the preliminary data coming from these pioneering studies.

A phase 2 trial of regorafenib as a single agent in patients with chemotherapy-refractory, advanced, and metastatic biliary tract adenocarcinoma

BACKGROUND

Biliary tract cancers are rare, aggressive neoplasms. Most patients present with advanced/unresectable or metastatic disease at diagnosis, and no second-line regimen has demonstrated clinical benefit. This was a phase 2 study evaluating the efficacy and safety of regorafenib in patients who had advanced/unresectable or metastatic disease after receiving standard therapy.

METHODS

In this single arm-study, patients with advanced/unresectable or metastatic biliary tract cancer who failed at least 1 line of systemic chemotherapy received regorafenib once daily on a schedule of 21-days on/7-days off in a 28-day cycle. Patients initially received a standard 160 mg dose. After toxicity assessments in the first 3 patients, the dose was reduced to 120 mg for subsequent patients, as preplanned. The primary endpoint was progression-free survival (PFS). Secondary objectives included overall survival (OS), the objective response rate, and the disease control rate.

RESULTS

Forty-three patients received at least 1 dose of regorafenib, and 34 patients who received at least 1 cycle of treatment were evaluable for tumor response. The median PFS was 15.6 weeks (90% confidence interval, 12.9-24.7 weeks), and the median OS was 31.8 weeks (90% confidence interval, 13.3-74.3 weeks), with survival rates 40% at 12 months and 32% at 18 months. A partial response was achieved in 5 patients (11%), and 19 had stable disease (44%), for a disease control rate of 56%. The toxicity profile was as expected, with grade 3 and 4 adverse events reported in 40% of patients. The most common toxicities were hypophosphatemia (40%), hyperbilirubinemia (26%), hypertension (23%), and hand-foot skin reaction (7%).

CONCLUSIONS

The current results suggest promising efficacy of regorafenib in patients with chemotherapy-refractory, advanced/metastatic biliary tract cancer, warranting further studies to confirm its clinical efficacy. There is a clear unmet need for effective therapies in patients who have advanced and metastatic biliary tract cancer.

Ramucirumab Plus Pembrolizumab in Patients with Previously Treated Advanced or Metastatic Biliary Tract Cancer: Nonrandomized, Open-Label, Phase I Trial (JVDF)

LESSONS LEARNED

Ramucirumab plus pembrolizumab revealed no unexpected safety findings in patients with advanced or metastatic biliary tract cancer, which is consistent with reports of other tumor cohorts within this phase Ia/b trial.Ramucirumab plus pembrolizumab did not demonstrate an improvement in overall survival when compared with historical controls in biomarker unselected, heavily pretreated patients with advanced or metastatic biliary tract cancer.Patients with programmed death-ligand 1 (PD-L1)-positive tumors had improved overall survival compared with patients with PD-L1-negative disease.

BACKGROUND

Few treatment options exist for patients with advanced biliary tract cancer (BTC) following progression on gemcitabine-cisplatin. Preclinical evidence suggests that simultaneous blockade of vascular endothelial growth factor receptor 2 (VEGFR-2) and programmed death 1 (PD-1) or programmed death-ligand 1 (PD-L1) enhances antitumor effects. We assessed the safety and efficacy of ramucirumab, an IgG1 VEGFR-2 antagonist, with pembrolizumab, an IgG4 PD-1 antagonist, in biomarker-unselected patients with previously treated advanced or metastatic BTC.

METHODS

Patients had previously treated advanced or metastatic adenocarcinoma of the gallbladder, intrahepatic and extrahepatic bile ducts, or ampulla of Vater. Ramucirumab 8 mg/kg was administered intravenously on days 1 and 8 with intravenous pembrolizumab 200 mg on day 1 every 3 weeks. The primary endpoint was safety and tolerability of the combination. Secondary endpoints included objective response rate (ORR), progression-free survival (PFS), and overall survival (OS).

RESULTS

Twenty-six patients were treated at 12 centers in five countries. Hypertension was the most common grade 3 treatment-related adverse event (TRAE), occurring in five patients. One patient experienced a grade 4 TRAE (neutropenia), and no treatment-related deaths occurred. Objective response rate was 4%. Median progression-free survival and overall survival were 1.6 months and 6.4 months, respectively.

CONCLUSION

Ramucirumab-pembrolizumab showed limited clinical activity with infrequent grade 3-4 TRAEs in patients with biomarker-unselected progressive BTC.

Apatinib for treating advanced intrahepatic cholangiocarcinoma after failed chemotherapy: A case report and literature review

RATIONALE

Intrahepatic cholangiocarcinoma (ICC) originates from the secondary branch of the bile duct and the intrahepatic bile duct epithelial cells, and is a rare pathological type of primary liver cancer. Recently, apatinib has been successfully used for a variety of malignancies.

PATIENT CONCERNS

A 23-year-old female was noted with intermittent right upper abdominal distension, abdominal pain, and vomiting after eating for more than 1 month. The enhanced CT scan revealed multiple intrahepatic lesions, portal vein and right branch tumor emboli were present.

DIAGNOSIS

Combined with the patient's medical history and pathology and immunohistochemistry, the diagnosis was confirmed as locally advanced unresectable ICC (cT4N1M1, Stage IVB).

INTERVENTIONS

The disease progressed after six cycles of gemcitabine plus capecitabine chemotherapy. She received oral apatinib treatment since September 30, 2017. Due to related adverse reactions, the patient could not tolerate the treatment, and the subsequent reduction therapy was given.

OUTCOMES

On April 11, 2018, the review of CT evaluation suggested that the disease was progressed. Hence, in this patient, apatinib as second-line treatment for advanced ICC showed a progression-free survival with 6 months.

LESSONS

Apatinib as second-line treatment for advanced ICC is effective, and the adverse effects are tolerable. However, the efficacy and safety of apatinib in the treatment of ICC need to be further confirmed by large sample of prospective randomized controlled trials.

Progress in molecular targeted therapy of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma is an uncommon malignant tumor with a poor prognosis due to an incomplete understanding of its molecular pathogenesis and a lack of effective treatment. Precision medical planning and cancer genomics can help to understand the molecular pathogenesis of cancer and identify potential therapeutic targets. With the deepening of basic and clinical research, accurate targeted therapy will be able to improve the prognosis and overall survival of patients with intrahepatic cholangiocarcinoma.

Novel targeted treatment options for advanced cholangiocarcinoma

INTRODUCTION

Surgical resection remains the mainstay of potentially curative treatment in the early stages of cholangiocarcinoma, whereas for the advanced stage, systemic chemotherapeutics and experimental targeted therapies are the primary treatment options. The molecular heterogeneity of the tumor is based on location, liver dysfunction, and relative rarity of the disease and confers challenges for clinical trial enrollment. The advancements in the understanding of molecular pathogenesis of cholangiocarcinoma have led to the development of targeted therapies that are currently being evaluated in the clinical trials.

AREAS COVERED

This review summarizes the current understanding and future directions of targeted therapeutic options in the management of advanced cholangiocarcinoma.

EXPERT OPINION

Advanced cholangiocarcinoma has a dismal prognosis; improved understanding of the molecular pathogenesis and advancements in development of targeted therapy offers hope that we may improve outcomes in this rare, but highly lethal cancer. Among the newly discovered molecular alterations, targeting FGFR2 fusions, IDH1/2 mutations and HER2 receptors hold great promise for improving the future management of cholangiocarcinoma. Immunotherapy in combination with targeted agents and chemotherapy may improve outcomes. In addition, drugs targeting the MEK, EGFR, KRAS, BRAF, and ROS1 pathways and neo-angiogenesis may also provide new horizons in the management of cholangiocarcinoma.

Precision medicine in cholangiocarcinoma

Cholangiocarcinoma is one of the epithelial cancers with the poorest prognosis and the narrowest therapeutic choice in humans. Compared with other cancer types, cholangiocarcinoma has been often neglected by oncology and liver research studies, thereby leaving many issues unsolved. Apart from the early and marked aggressiveness, one of the main reasons of the still unsatisfying clinical management of cholangiocarcinoma is its wide tumor heterogeneity needing more than other diseases a 'precision medicine' approach. In this regard, in the last few years there has been an awakening of interest aimed at dissecting the complex molecular and genomic profile of cholangiocarcinoma. Thus, a range of molecular players have been recently identified as putative mechanistic determinants of cholangiocarcinoma invasiveness, encompassing tyrosine kinase receptors, metabolic enzymes, transcription factors, small GTPases, ubiquitin ligases, and chromatin-remodelling proteins, whose aberrant expression may derive from stochastic mutations as well as from pro-oncogenic paracrine signals released by the stromal microenvironment, which is particularly exuberant in cholangiocarcinoma. Herein, we sought to overview the most relevant observations unravelling the genomic landscape of cholangiocarcinoma, and the prognostic and predictive biomarkers that consequently have been emerging. Then, we will discuss innovative treatment approaches derived from conventional chemotherapy, targeted therapies, antiangiogenic therapies and immunotherapy, and how they are opening new avenues towards a precision medicine in cholangiocarcinoma.

Second-line therapy in advanced upper gastrointestinal cancers: current status and new prospects

The prognosis of patients with advanced upper gastrointestinal cancers (UGC) remains poor. Current available systemic armamentarium is limited, and little progress has been made over the last decades. Main achievements have been obtained in first-line setting, however an increasingly proportion of patients are considered for second-line therapy, although data from randomized trials are scarce or even lacking. In this comprehensive review we examine the literature to summarize the efficacy and limitations of second-line systemic options in patients with advanced UGC, with a glimpse into the innovations.

Targeting cholangiocarcinoma

Cholangiocarcinoma (CCA) represents a diverse group of epithelial cancers associated with the biliary tract, and can best be stratified anatomically into intrahepatic (iCCA), perihilar (pCCA) and distal (dCCA) subsets. Molecular profiling has identified genetic aberrations associated with these anatomic subsets. For example, IDH catalytic site mutations and constitutively active FGFR2 fusion genes are predominantly identified in iCCA, whereas KRAS mutations and PRKACB fusions genes are identified in pCCA and dCCA. Clinical trials targeting these specific driver mutations are in progress. However, The Tumor Genome Atlas (TCGA) marker analysis of CCA also highlights the tremendous molecular heterogeneity of this cancer rendering comprehensive employment of targeted therapies challenging. CCA also display a rich tumor microenvironment which may be easier to target. For example, targeting cancer associated fibroblasts for apoptosis with BH3-mimetics and/or and reversing T-cell exhaustion with immune check point inhibitors may help aid in the treatment of this otherwise devastating malignancy. Combinatorial therapy attacking the tumor microenvironment plus targeted therapy may help advance treatment for CCA. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

Immunotherapeutic Approaches to Biliary Cancer

OPINION STATEMENT

Biliary tract cancers (BTCs) are rare aggressive neoplasms with a poor prognosis and a median survival of less than 1 year in the locally advanced or metastatic setting. Among the few patients who undergo curative resection the recurrence rates are high. About 90% of patients are detected at advanced stages, and systemic chemotherapy is the mainstay of their treatment. The treatment options for these patients are limited and multiple modalities of therapy from targeted therapy to immunotherapy and combination therapies (immunotherapy, targeted therapy, and chemotherapy) have been tested in this disease. Targeted therapies have failed to show a survival benefit. The deregulation of the immune system plays a significant role in the pathogenesis of BTCs. Therefore, immunotherapy, especially, immune checkpoint inhibitors hold great promise for this group of cancers. Numerous trials of immunotherapy in BTC are currently ongoing. In this review, we will discuss the available data and evidence for immunotherapy in BTC.

Biomarker-Driven and Molecular Targeted Therapies for Hepatobiliary Cancers

The recent accumulation of molecular profiling data for primary hepatobiliary malignancies, including hepatocellular carcinoma and biliary tract cancers, has led to a proliferation of promising therapeutic investigations in recent years. Treatment with pathway-specific targeted inhibitors and immunotherapeutic agents have demonstrated promising early clinical results. Key molecular alterations in common hepatobiliary cancers and ongoing interventional clinical trials of molecularly targeted systemic agents focusing on hepatocellular carcinoma and biliary tract cancer are reviewed.

Ceruloplasmin as a prognostic marker in patients with bile duct cancer

BACKGROUND AND AIMS

Bile duct cancer is one of the lethal cancers, presenting difficulties in early diagnosis and limited treatment modalities. Despite current advances in biomarker research, most studies have been performed in Western populations. Therefore, the purpose of this study was to determine a prognostic marker for bile duct cancer, especially in Korean patients, whose incidence of bile duct cancer is high.

RESULTS

Comparing cancer and normal bile duct tissue, we identified 29091 differentially expressed genes. CP, SCEL, and MUC16 had positive coefficients with a log2 ratio >1 for advanced T, N stage and perineural invasion cancer tissue. Strong immunohistochemical expression of ceruloplasmin was dominant in tumors with advanced T stage (p>0.999) and perineural invasion (p=0.316).

PATIENTS AND METHODS

We performed tissue microarray experiment with 79 bile duct cancer tissue samples and 21 normal bile duct tissue samples. Candidate genes that has positive correlation with T, N stage and perineural invasion were drawn with multivariate analysis. Tissue expression of the genes was evaluated with an immunohistochemical study.

CONCLUSIONS

Ceruloplasmin is supposed to be related with advanced T stage and perineural invasion, having a possibility as a candidate prognostic marker for bile duct cancer.

Emerging molecular target antagonists for the treatment of biliary tract cancer

INTRODUCTION

Biliary tract cancers (BTCs) are a heterogeneous group of cancers, characterized by low incidence but poor prognosis. Even after complete surgical resection for early stage, relapse is frequent and the lack of effective treatments contributes to the dismal prognosis. To date, the only standard treatment in first-line is cisplatin/gemcitabine combination, whereas no standard in 2nd-line has been defined. Hence, the current goal is to better understand the biology of BTCs, discovering new treatment methods and improving clinical outcomes. Areas covered: The development of next-generation-sequencing has unveiled the picture of the molecular signatures characterizing BTCs, leading to the identification of actionable mutations in biomarker-driven clinical trials. In this review we will cover the genetic landscape of BTC, focusing on the efficacy of existing treatments. Furthermore, we will discuss emerging molecular targets and evaluate the findings of pre-clinical studies. Finally, the encouraging results of clinical trials involving targeted therapies or immunotherapy will be reviewed. Expert opinion: FGFR fusion rearrangements and IDH1 or IDH2 mutations are the most promising targeted treatments under evaluation. In addition, innovative trial design will allow to offer a chance for tailored medicine to infrequent subgroups of BTCs patients based on their molecular features rather than their histology.

The landscape of targeted therapies for cholangiocarcinoma: current status and emerging targets

Cholangiocarcinoma (CCA) is a relatively rare malignancy that arises from the epithelial cells of the intrahepatic, perihilar and distal biliary tree. Intrahepatic CCA (ICC) represents the second most common primary liver cancer, after hepatocellular cancer. Two-thirds of the patients with ICC present with locally advanced or metastatic disease. Despite standard treatment with gemcitabine and cisplatin, prognosis remains dismal with a median survival of less than one year. Several biological plausibilities can account for its poor clinical outcomes. First, despite the advent of next generation and whole exome sequencing, no oncogenic addiction loops have been validated as clinically actionable targets. Second, the anatomical, pathological and molecular heterogeneity, and rarity of CCA confer an ongoing challenge of instituting adequately powered clinical trials. Last, most of the studies were not biomarker-driven, which may undermine the potential benefit of targeted therapy in distinct subpopulations carrying the unique molecular signature. Recent whole genome sequencing efforts have identified known mutations in genes such as epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), v-raf murine sarcoma viral oncogene homolog (BRAF) and tumor protein p53 (TP53), novel mutations in isocitrate dehydrogenase (IDH), BRCA1-Associated Protein 1 (BAP1) and AT-rich interactive domain-containing protein 1A (ARID1A), and novel fusions such as fibroblast growth factor receptor 2 (FGFR2) and ROS proto-oncogene 1 (ROS1). In this review, we will discuss the evolving genetic landscape of CCA, with an in depth focus on novel fusions (e.g. FGFR2 and ROS1) and somatic mutations (e.g. IDH1/2), which are promising actionable molecular targets.

Incidence, risk and prognostic role of anti-epidermal growth factor receptor-induced skin rash in biliary cancer: a meta-analysis

BACKGROUND

Anti-epidermal growth factor receptor (EGFR)-induced skin rash is a common adverse event and is considered a prognostic factor of various cancers. However, the role of rash is rarely known in biliary cancer, possibly owing to the low incidence of this frequently fatal malignancy. We thus performed a meta-analysis to investigate the incidence, risk and prognostic significance of skin rash related to anti-EGFR treatment for biliary cancer.

METHODS

Eligible studies were enrolled after a systematic search of electronic databases. A fixed-effects or random-effects model was utilized according to the heterogeneity.

RESULTS

Fourteen clinical trials published between 2006 and 2017 comprising 1,106 patients with advanced biliary cancer were included. The overall incidence of all-grade and high-grade (grade ≥3) rash was 78.2% [95% confidence interval (CI) 70.4-84.3] and 11.3% (7.6-16.5), respectively. Anti-EGFR treatment correlates with a significantly increased risk of all-grade [risk ratio (RR) 7.37, 95% CI 5.11-10.64, p < 0.0001] and high-grade (RR 6.94, 95% CI 1.89-25.45, p = 0.0035) rash compared with control medication. Higher grades of skin rash correlate with a higher objective response rate (RR 3.50, 95% CI 1.47-8.33, p = 0.0048), and a longer overall [hazard ratio (HR) 0.47, 95% CI 0.31-0.71, p = 0.0003) and progression-free survival (HR 0.51, 95% CI 0.36-0.72, p = 0.0001) compared with lower grades or no rash in patients who received anti-EGFR treatment.

CONCLUSIONS

Anti-EGFR treatment correlates with an increased risk of skin rash in advanced biliary cancer. Stratifying patients by the severity of rash may have major implications for survival benefit regarding anti-EGFR treatment for biliary cancer.

Dosing de novo combinations of two targeted drugs: Towards a customized precision medicine approach to advanced cancers

Metastatic cancers harbor complex genomic alterations. Thus, monotherapies are often suboptimal. Individualized combinations are needed in order to attenuate resistance. To help inform selection of safe starting doses for novel, two-agent, targeted drug combinations, we identified clinical trials in adult oncology patients who received targeted drug doublets (PubMed, January 1, 2010 through December 31, 2013). The dose percentage was calculated for each drug: (safe dose in combination divided by single agent full dose) X 100. Additive dose percentage represented the sum of the dose percentage for each drug. A total of 144 studies (N = 8568 patients; 95 combinations) were analyzed. In 51% of trials, each of the two drugs could be administered at 100% of their full dose. The lowest safe additive dose percentage was 60% if targets and/or class of drugs overlapped, or in the presence of mTor inhibitors, which sometimes compromised the combination dose. If neither class nor target overlapped and if mTor inhibitors were absent, the lowest safe additive dose percentage was 143%. The current observations contribute to the knowledge base that informs safe starting doses for new combinations of targeted drugs in the context of clinical trials or practice, hence facilitating customized combination therapies.

Emerging molecular therapeutic targets for cholangiocarcinoma

Cholangiocarcinomas (CCAs) are diverse epithelial tumors arising from the liver or large bile ducts with features of cholangiocyte differentiation. CCAs are classified anatomically into intrahepatic (iCCA), perihilar (pCCA), and distal CCA (dCCA). Each subtype has distinct risk factors, molecular pathogenesis, therapeutic options, and prognosis. CCA is an aggressive malignancy with a poor overall prognosis and median survival of less than 2years in patients with advanced disease. Potentially curative surgical treatment options are limited to the subset of patients with early-stage disease. Presently, the available systemic medical therapies for advanced or metastatic CCA have limited therapeutic efficacy. Molecular alterations define the differences in biological behavior of each CCA subtype. Recent comprehensive genetic analysis has better characterized the genomic and transcriptomic landscape of each CCA subtype. Promising candidates for targeted, personalized therapy have emerged, including potential driver fibroblast growth factor receptor (FGFR) gene fusions and somatic mutations in isocitrate dehydrogenase (IDH)1/2 in iCCA, protein kinase cAMP-activated catalytic subunit alpha (PRKACA) or beta (PRKACB) gene fusions in pCCA, and ELF3 mutations in dCCA/ampullary carcinoma. A precision genomic medicine approach is dependent on an enhanced understanding of driver mutations in each subtype and stratification of patients according to their genetic drivers. We review the current genomic landscape of CCA, the potentially actionable molecular aberrations in each CCA subtype, and the role of immunotherapy in CCA.

New Horizons for Precision Medicine in Biliary Tract Cancers

Biliary tract cancers (BTC), including cholangiocarcinoma and gallbladder cancer, are poor-prognosis and low-incidence cancers, although the incidence of intrahepatic cholangiocarcinoma is rising. A minority of patients present with resectable disease but relapse rates are high; benefit from adjuvant capecitabine chemotherapy has been demonstrated. Cisplatin/gemcitabine combination chemotherapy has emerged as the reference first-line treatment regimen; there is no standard second-line therapy. Selected patients may be suitable for liver-directed therapy (e.g., radioembolization or external beam radiation), pending confirmation of benefit in randomized studies. Initial trials targeting the epithelial growth factor receptor and angiogenesis pathways have failed to deliver new treatments. Emerging data from next-generation sequencing analyses have identified actionable mutations (e.g., FGFR fusion rearrangements and IDH1 and IDH2 mutations), with several targeted drugs entering clinical development with encouraging results. The role of systemic therapies, including targeted therapies and immunotherapy for BTC, is rapidly evolving and is the subject of this review.Significance: The authors address genetic drivers and molecular biology from a translational perspective, in an intent to offer a clear view of the recent past, present, and future of BTC. The review describes a state-of-the-art update of the current status and future directions of research and therapy in advanced BTC. Cancer Discov; 7(9); 943-62. ©2017 AACR.

New Horizons for Precision Medicine in Biliary Tract Cancers

Biliary tract cancers (BTC), including cholangiocarcinoma and gallbladder cancer, are poor-prognosis and low-incidence cancers, although the incidence of intrahepatic cholangiocarcinoma is rising. A minority of patients present with resectable disease but relapse rates are high; benefit from adjuvant capecitabine chemotherapy has been demonstrated. Cisplatin/gemcitabine combination chemotherapy has emerged as the reference first-line treatment regimen; there is no standard second-line therapy. Selected patients may be suitable for liver-directed therapy (e.g., radioembolization or external beam radiation), pending confirmation of benefit in randomized studies. Initial trials targeting the epithelial growth factor receptor and angiogenesis pathways have failed to deliver new treatments. Emerging data from next-generation sequencing analyses have identified actionable mutations (e.g., FGFR fusion rearrangements and IDH1 and IDH2 mutations), with several targeted drugs entering clinical development with encouraging results. The role of systemic therapies, including targeted therapies and immunotherapy for BTC, is rapidly evolving and is the subject of this review.Significance: The authors address genetic drivers and molecular biology from a translational perspective, in an intent to offer a clear view of the recent past, present, and future of BTC. The review describes a state-of-the-art update of the current status and future directions of research and therapy in advanced BTC. Cancer Discov; 7(9); 943-62. ©2017 AACR.

Emerging molecular targets and therapy for cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare cancer arising from the biliary tree with a poor prognosis and limited therapeutic options. Recent large scale molecular characterisation studies have identified recurrent genetic alterations in CCA which may be amenable to therapeutic targeting. In this review we explore the genomic landscape of CCA and examine results from trials of molecularly targeted agents and immunotherapy in this disease. Challenges in CCA diagnosis, treatment and trial design are discussed and we reflect on future directions which may lead to improved outcomes for CCA patients.

Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway

Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

Current biologics for treatment of biliary tract cancers

Biliary tract cancers (BTC) is a group of malignancies that arise from the epithelial cells of the biliary tree. These cancers are typically classified by anatomic site of origin: intrahepatic cholangiocarcinoma (IHCC) and extrahepatic cholangiocarcinoma (EHCC), and gallbladder cancer (GBC). To date, complete surgical resection remains the mainstay of treatment especially for earlier stage disease. Unfortunately, most patients present with advanced or metastatic disease, when systemic chemotherapy is the only treatment option. Due to the paucity of effective treatments, BTCs have a dismal prognosis. There is a tremendous need to better understand the disease biology, discover new therapies, and improve clinical outcomes for this challenging disease. Next-generation sequencing has produced a more accurate and detailed picture of the molecular signatures in BTCs. The three BTC histologic subtypes are, in fact, quite molecularly distinct. IHCC commonly contain FGFR2 fusions and IDH 1 and 2 mutations, whereas EHCC and GBC tend to carry mutations in EGFR, HER2, and MAPK pathway. In light of this emerging knowledge, clinical trials have become more biomarker-driven, which allows capturing of subsets of patients that are most likely to respond to certain therapies. Many new and promising targeted therapeutics are currently in the pipeline. Here we review the genetic landscape of BTCs while focusing on new molecular targets and targeted therapeutics currently being investigated in biomarker-driven clinical trials.

L1 Cell Adhesion Molecule Promotes Migration and Invasion via JNK Activation in Extrahepatic Cholangiocarcinoma Cells with Activating KRAS Mutation

Extrahepatic cholangiocarcinoma (ECC), a malignant tumor of biliary origin, has a poor prognosis with limited treatment options. The KRAS oncogene is the most commonly mutated gene in ECC and one of the factors that predicts a poor prognosis and low survival rate. L1 cell adhesion molecule (L1CAM) is expressed in ECC cells and acts as an independent poor prognostic factor in predicting patient survival. In this study we investigate the functional significance of L1CAM in ECC cells with activating KRAS mutation. We selected an ECC cell line, EGI-1, with activating KRAS mutation, and then confirmed its expression of L1CAM by RT-PCR, western blot analysis, and flow cytometry. The suppression of L1CAM expression (using a specific lentivirus-delivered shRNA) significantly decreased the migratory and invasive properties of EGI-1 cells, without altering their proliferation or survival. Analyses of signaling effectors in L1CAM-depleted and control EGI-1 cells indicated that L1CAM suppression decreased the levels of both phosphorylated MKK4 and total MKK4, together with c-Jun N-terminal kinase (JNK) phosphorylation. Further, exposure to a JNK inhibitor (SP600125) decreased migration and invasion of EGI-1 cells. These results suggest that L1CAM promotes cellular migration and invasion via the induction of MKK4 expression, leading to JNK activation. Our study is the first to demonstrate a functional role for L1CAM in ECC carrying the activating KRAS mutation. Given that KRAS is the most commonly mutated oncogene in ECC, L1CAM may serve as an attractive therapeutic target for ECC cells with activating KRAS mutation.

[Chemotherapy for Biliary Tract Cancer]

The term of biliary tract cancer (BTC) refers to all tumors that arise from the biliary tract or the biliary drainage system, including the intra- and extra-hepatic bile ducts as well as the gallbladder. BTCs are aggressive tumors with limited treatment options and poor overall survival. Currently, surgery remains to be the only potentially curative treatment, and most patients develop recurrence. For advanced tumors, only limited effective treatment modalities exist today. Gemcitabine plus cisplatin is considered as a standard option for advanced biliary cancer. A randomized phase III trial (ABC-02 trial) showed superiority of gemcitabine plus cisplatin over gemcitabine alone. In that study, they showed that after a median follow-up of 8.2 months, the median overall survival was 8.1 months in the gemcitabine-only group and 11.7 months in the gemcitabine plus cisplatin group (p<0.001). However, while this is a definite advancement, a 3-month survival extension among patients with BTC is modest at best. Moreover, this regimen has not been compared head-to-head with other gemcitabine based combinations. Gemcitabine monotherapy, 5-fluorouracil plus leucovorin, and single-agent capecitabine are all reasonable options for patients with a borderline performance status. Recent advancements have provided new insight into the genomic landscape of BTCs, and thus, it remains unclear whether combined treatment with molecular targeted agents or other cytotoxic chemotherapeutic agents may also be effective against advanced BTC.

Understanding liver regeneration to bring new insights to the mechanisms driving cholangiocarcinoma

Cancer frequently arises in epithelial tissues subjected to repeated cycles of injury and repair. Improving our understanding of tissue regeneration is, therefore, likely to reveal novel processes with inherent potential for aberration that can lead to carcinoma. These highly conserved regenerative mechanisms are increasingly understood and in the liver are associated with special characteristics that underlie the organ's legendary capacity for restoration of size and function following even severe or chronic injury. The nature of the injury can determine the cellular source of epithelial regeneration and the signalling mechanisms brought to play. These observations are shaping how we understand and experimentally investigate primary liver cancer, in particular cholangiocarcinoma; a highly invasive malignancy of the bile ducts, resistant to chemotherapy and whose pathogenesis has hitherto been poorly understood. Interestingly, signals that drive liver development become activated in the formation of cholangiocarcinoma, such as Notch and Wnt and may be potential future therapeutic targets. In this review, we summarise the work which has led to the current understanding of the cellular source of cholangiocarcinoma, how the tumour recruits, sustains and is educated by its supporting stromal environment, and the tumour-derived signals that drive the progression and invasion of the cancer. With few current treatments of any true efficacy, advances that will improve our understanding of the mechanisms driving this aggressive malignancy are welcome and may help drive therapeutic developments.

Intrahepatic cholangiocarcinoma: current management and emerging therapies

Intrahepatic cholangiocarcinoma (iCCA) is a malignancy with an increasing incidence and a high-case fatality. While surgery offers the best hope at long-term survival, only one-third of tumors are amenable to surgical resection at the time of the diagnosis. Unfortunately, conventional chemotherapy offers limited survival benefit in the management of unresectable or metastatic disease. Recent advances in understanding the molecular pathogenesis of iCCA and the use of next-generation sequencing techniques have provided a chance to identify 'target-able' molecular aberrations. These novel molecular therapies offer the promise to personalize therapy for patients with iCCA and, in turn, improve the outcomes of patients. Area covered: We herein review the current management options for iCCA with a focus on defining both established and emerging therapies. Expert commentary: Surgical resection remains as an only hope for cure in iCCA patients. However, frequently the diagnosis is delayed till advanced stages when surgery cannot be offered; signifying the urge for specific diagnostic tumor biomarkers and targeted therapies. New advances in genomic profiling have contributed to a better understanding of the landscape of molecular alterations in iCCA and offer hope for the development of novel diagnostic biomarkers and targeted therapies.