IDH Signalling Pathway in Cholangiocarcinoma: From Biological Rationale to Therapeutic Targeting

PIWI-interacting RNAs (PiRNAs) as emerging biomarkers and therapeutic targets in biliary tract cancers: A comprehensive review

Cancers affecting the biliary tract, such as gallbladder cancer and cholangiocarcinoma, make up a small percentage of adult gastrointestinal malignancies, but their incidence is on the rise. Due to the lack of dependable molecular biomarkers for diagnosis and prognosis, these cancers are often not detected until later stages and have limited treatment options. Piwi-interacting RNAs (piRNAs) are a type of small noncoding RNA that interacts with Piwi proteins and has been linked to various diseases, especially cancer. Manipulation of piRNA expression has the potential to serve as an important biomarker and target for therapy. This review uncovers the relationship between PIWI-interacting RNA (piRNA) and a variety of gastrointestinal cancers, including biliary tract cancer (BTC). It is evident that piRNAs have the ability to impact gene expression and regulate key genes and pathways related to the advancement of digestive cancers. Abnormal expression of piRNAs plays a significant role in the development and progression of digestive-related malignancies. The potential of piRNAs as potential biomarkers for diagnosis and prognosis, as well as therapeutic targets in BTC, is noteworthy. Nevertheless, there are obstacles and limitations that require further exploration to fully comprehend piRNAs' role in BTC and to devise effective diagnostic and therapeutic approaches using piRNAs. In summary, this review underscores the value of piRNAs as valuable biomarkers and promising targets for treating BTC, as we delve into the association between piRNAs and various gastrointestinal cancers, including BTC, and how piRNAs can impact gene expression and control essential pathways for digestive cancer advancement. The present research consists of a thorough evaluation presented in a storytelling style. The databases utilized to locate original sources were PubMed, MEDLINE, and Google Scholar, and the search was conducted using the designated keywords.

Molecular Targeting of the Isocitrate Dehydrogenase Pathway and the Implications for Cancer Therapy

The advent of comprehensive genomic profiling using next-generation sequencing (NGS) has unveiled an abundance of potentially actionable genetic aberrations that have shaped our understanding of the cancer biology landscape. Isocitrate dehydrogenase (IDH) is an enzyme present in the cytosol (IDH1) and mitochondria (IDH2 and IDH3). In the mitochondrion, it catalyzes the irreversible oxidative decarboxylation of isocitrate, yielding the production of α-ketoglutarate and nicotinamide adenine dinucleotide phosphate (NADPH) as well as carbon dioxide (CO2). In the cytosol, IDH catalyzes the decarboxylation of isocitrate to α-ketoglutarate as well as the reverse reductive carboxylation of α-ketoglutarate to isocitrate. These rate-limiting steps in the tricarboxylic acid cycle, as well as the cytoplasmic response to oxidative stress, play key roles in gene regulation, cell differentiation, and tissue homeostasis. Mutations in the genes encoding IDH1 and IDH2 and, less commonly, IDH3 have been found in a variety of cancers, most commonly glioma, acute myeloid leukemia (AML), chondrosarcoma, and intrahepatic cholangiocarcinoma. In this paper, we intend to elucidate the theorized pathophysiology behind IDH isomer mutation, its implication in cancer manifestation, and discuss some of the available clinical data regarding the use of novel IDH inhibitors and their role in therapy.

Molecular biology of cholangiocarcinoma and its implications for targeted therapy in patient management

Cholangiocarcinoma (CCA) remains a devastating malignancy and a significant challenge to treat. The majority of CCA patients are diagnosed at an advanced stage, making the disease incurable in most cases. The advent of high-throughput genetic sequencing has significantly improved our understanding of the molecular biology underpinning cancer. The identification of 'druggable' genetic aberrations and the development of novel targeted therapies against them is opening up new treatment strategies. Currently, 3 targeted therapies are approved for use in CCA; Ivosidenib in patients with IDH1 mutations and Infigratinib/Pemigatinib in those with FGFR2 fusions. As our understanding of the biology underpinning CCA continues to improve it is highly likely that additional targeted therapies will become available in the near future. This is important, as it is thought up to 40 % of CCA patients harbour a potentially actionable mutation. In this review we provide an overview of the molecular pathogenesis of CCA and highlight currently available and potential future targeted treatments.

Perioperative and palliative systemic treatments for biliary tract cancer

Due to the fact biliary tract cancer (BTC) is often diagnosed at an advanced stage, thus, not eligible for resection, and due to the aggressive tumor biology, it is considered as one of the cancer types with the worst prognosis. Advances in diagnosis, surgical techniques, and molecular characterization have led to an improvement of the prognosis of BTC patients, recently. Although neoadjuvant therapy is expected to improve surgical outcomes by reducing tumor size, its routine is not well established. The application of neoadjuvant therapy in locally advanced disease may be indicated, the routine use of systemic therapy prior to surgery for cholangiocarcinoma patients with an upfront resectable disease is less well established, but discussed and performed in selected cases. In advanced disease, only combination chemotherapy regimens have been demonstrated to achieve disease control in untreated patients. Molecular profiling of the tumor has demonstrated that many BTC might bear actionable targets, which might be addressed by biological treatments, thus improving the prognosis of the patients. Furthermore, the addition of the immunotherapy to standard chemotherapy might improve the prognosis in a subset of patients. This review seeks to give a comprehensive overview about the role of neoadjuvant as well as palliative systemic treatment approaches and an outlook about novel systemic treatment concept in BTC.

Therapeutic Targeting of Hypoxia-Inducible Factors in Cancer

In the realm of cancer therapeutics, targeting the hypoxia-inducible factor (HIF) pathway has emerged as a promising strategy. This study delves into the intricate web of HIF-associated mechanisms, exploring avenues for future anticancer therapies. Framing the investigation within the broader context of cancer progression and hypoxia response, this article aims to decipher the pivotal role played by HIF in regulating genes influencing angiogenesis, cell proliferation, and glucose metabolism. Employing diverse approaches such as HIF inhibitors, anti-angiogenic therapies, and hypoxia-activated prodrugs, the research methodologically intervenes at different nodes of the HIF pathway. Findings showcase the efficacy of agents like EZN-2968, Minnelide, and Acriflavine in modulating HIF-1α protein synthesis and destabilizing HIF-1, providing preliminary proof of HIF-1α mRNA modulation and antitumor activity. However, challenges, including toxicity, necessitate continued exploration and development, as exemplified by ongoing clinical trials. This article concludes by emphasizing the potential of targeted HIF therapies in disrupting cancer-related signaling pathways.

Fluke-Related Cholangiocarcinoma: Challenges and Opportunities

Cholangiocarcinoma encompasses a heterogeneous group of highly aggressive malignancies, arising from the biliary tract, that are often associated with poor survival rates [...].

Potential agnostic role of BRCA alterations in patients with several solid tumors: One for all, all for one?

Germline BRCA1/2 alterations in the Homologous Recombination (HR) pathway are considered as main susceptibility biomarkers to Hereditary Breast and Ovarian Cancers (HBOC). The modern molecular biology technologies allowed to characterize germline and somatic BRCA1/2 alterations in several malignancies, broadening the landscape of BRCA1/2-alterated tumors. In the last years, BRCA genetic testing, beyond the preventive value, also assumed a predictive and prognostic significance for patient management. The approval of molecules with agnostic indication is leading to a new clinical model, defined "mutational". Among these drugs, the Poly (ADP)-Ribose Polymerase inhibitors (PARPi) for BRCA1/2-deficient tumors were widely studied leading to increasing therapeutic implications. In this Review we provided an overview of the main clinical studies describing the association between BRCA-mutated tumors and PARPi response, focusing on the controversial evidence about the potential agnostic indication based on BRCA1/2 alterations in several solid tumors.

Exploring the Molecular Landscape of Myelofibrosis, with a Focus on Ras and Mitogen-Activated Protein (MAP) Kinase Signaling

Myelofibrosis (MF) is a clonal myeloproliferative neoplasm (MPN) characterized clinically by cytopenias, fatigue, and splenomegaly stemming from extramedullary hematopoiesis. MF commonly arises from mutations in JAK2, MPL, and CALR, which manifests as hyperactive Jak/Stat signaling. Triple-negative MF is diagnosed in the absence of JAK2, MPL, and CALR but when clinical, morphologic criteria are met and other mutation(s) is/are present, including ASXL1, EZH2, and SRSF2. While the clinical and classic molecular features of MF are well-established, emerging evidence indicates that additional mutations, specifically within the Ras/MAP Kinase signaling pathway, are present and may play important role in disease pathogenesis and treatment response. KRAS and NRAS mutations alone are reportedly present in up to 15 and 14% of patients with MF (respectively), and other mutations predicted to activate Ras signaling, such as CBL, NF1, BRAF, and PTPN11, collectively exist in as much as 21% of patients. Investigations into the prevalence of RAS and related pathway mutations in MF and the mechanisms by which they contribute to its pathogenesis are critical in better understanding this condition and ultimately in the identification of novel therapeutic targets.

A phosphatase-recruiting bispecific antibody-aptamer chimera for enhanced suppression of tumor growth

The development of agents against abnormal activation of receptor tyrosine kinases (RTKs) for therapeutic interventions is in high demand. Using mesenchymal epithelial transition (Met) protein as a proof-of-concept RTK, here we developed a CD148-recruiting bispecific antibody-aptamer chimera for simultaneous inhibition of extra- and intra-cellular functions of Met in cancer cells. This chimera exhibited remarkable migration-suppressive and antiproliferative effects. This strategy is highly promising for developing kinase inhibitors for use in therapies of a broad range of cancers.

Targeting Oncometabolites in Peritoneal Cancers: Preclinical Insights and Therapeutic Strategies

Peritoneal cancers present significant clinical challenges with poor prognosis. Understanding the role of cancer cell metabolism and cancer-promoting metabolites in peritoneal cancers can provide new insights into the mechanisms that drive tumor progression and can identify novel therapeutic targets and biomarkers for early detection, prognosis, and treatment response. Cancer cells dynamically reprogram their metabolism to facilitate tumor growth and overcome metabolic stress, with cancer-promoting metabolites such as kynurenines, lactate, and sphingosine-1-phosphate promoting cell proliferation, angiogenesis, and immune evasion. Targeting cancer-promoting metabolites could also lead to the development of effective combinatorial and adjuvant therapies involving metabolic inhibitors for the treatment of peritoneal cancers. With the observed metabolomic heterogeneity in cancer patients, defining peritoneal cancer metabolome and cancer-promoting metabolites holds great promise for improving outcomes for patients with peritoneal tumors and advancing the field of precision cancer medicine. This review provides an overview of the metabolic signatures of peritoneal cancer cells, explores the role of cancer-promoting metabolites as potential therapeutic targets, and discusses the implications for advancing precision cancer medicine in peritoneal cancers.

Conventional Chondrosarcoma of the Rib Cage and Sternum: Clinicopathological and Molecular Analysis of 27 Patients Treated at a Single Institution

Conventional chondrosarcoma of the chest wall is rare, accounting for 15% of cases. Our purpose was to document clinicopathological, imaging and outcome results from a novel set of chest wall chondrosarcomas, and to analyze for <I>IDH</I> mutations and novel molecular alterations. Gross and microscopic pathology, imaging and clinical charts were reviewed. Targeted next-generation sequencing was performed to identify somatic mutations and copy number alterations. The cohort consisted of 27 patients: 16 men and 11 women (mean age 51 years; range 23-76). Palpable mass was the most common presentation. Five were discovered incidentally. Among 20 tumors with complete imaging, 15 arose from a rib and 5 from the sternum. Seven rib tumors were central/intramedullary, 5 were periosteal, 2 were secondary peripheral chondrosarcomas, and one was indeterminate. Among sternal tumors, 4 were central/intramedullary and one was periosteal. Half the periosteal tumors arose from the costochondral junctional cartilage (CCJ). Periosteal chondrosarcomas were sometimes mistaken for extraskeletal masses on initial clinical or radiological examinations. Fifty-nine percent of all tumors were grade 1 and 41% were grade 2. None were dedifferentiated chondrosarcomas. Heterozygous <I>IDH1</I> mutation was detected in one tumor and heterozygous <I>RAD50</I> mutation in another. Local recurrence(s) happened in 41% and metastasis in 41%. Grade had strong association with local recurrence (25% grade 1 vs. 64% grade 2 [p=0.0447]), metastatic recurrence (19% grade 1 vs. 73% grade 2 [p=0.0058]), and survival. Although chest wall chondrosarcomas share morphologic and molecular features with other chondrosarcomas, there is a much higher incidence of periosteal chondrosarcomas. <I>IDH</I> mutant tumors are uncommon. Early diagnosis and margin-negative resection is treatment of choice since chondrosarcomas are chemo- and radioresistant.

Precision Oncology Targets in Biliary Tract Cancer

Targeted therapies in biliary tract cancer (BTC) are emerging as options for patients not who do not respond to first-line treatment. Agents acting on tumor-specific oncogenes in BTC may target fibroblast growth factor receptor 2 (FGFR2), isocitrate dehydrogenase (IDH), B-raf kinase (BRAF), and human epidermal growth factor receptor 2 (HER-2). Additionally, given the heterogeneous genetic landscape of advanced BTCs, many harbor genetic aberrations that are common among solid tumors, including RET fusions, tropomyosin receptor kinase (TRK) fusions, and high tumor mutational burden (TMB). This review aims to provide updates on the evolving array of therapeutics available, and to summarize promising works on the horizon.

Urolithin A targets the AKT/WNK1 axis to induce autophagy and exert anti-tumor effects in cholangiocarcinoma

Urolithin A (UA; 3,8-dihydroxybenzo[c]chromen-6-one), a metabolite generated by intestinal bacteria during the biotransformation of ellagitannins, has gained considerable attention in treating several cancers. Cholangiocarcinoma (CCA) remains one of the most lethal cancers; it grows in a special environment constantly exposed to both blood and bile. Since UA is known to undergo enterohepatic recirculation, we hypothesized that UA might have significant antitumor effects in CCA. Here, we investigated the therapeutic potential of UA in CCA and aimed to elucidate its mechanisms, including autophagy. UA treatment inhibited cell proliferation and induced G2/M phase cell cycle arrest in CCA cells. UA also suppressed cell migration and invasion, but did not cause apoptosis. Furthermore, Western blotting and immunocytochemistry demonstrated increased LC3-II accumulation, while electron microscopy demonstrated induced autophagosomes after UA treatment, suggesting that UA upregulated autophagy in CCA cells. In xenograft mice treated with UA, tumor growth was inhibited with increased LC3-II levels. On the other hand, phospho-kinase array demonstrated downregulation of the AKT/WNK1 pathway. LC3-II expression was elevated in WNK1 knocked down cells, indicating that WNK1 is the key signal for regulating autophagy. Thus, UA exerted antitumor effects by suppressing the AKT/WNK1 signaling pathway and inducing autophagy. In conclusion, UA, a natural, well-tolerated compound, may be a promising therapeutic candidate for advanced CCA.

Secondary IDH1 resistance mutations and oncogenic IDH2 mutations cause acquired resistance to ivosidenib in cholangiocarcinoma

The mutant IDH1 inhibitor ivosidenib improves outcomes for patients with IDH1-mutated cholangiocarcinoma, but resistance inevitably develops. Mechanisms of resistance and strategies to overcome resistance are poorly understood. Here we describe two patients with IDH1 R132C-mutated metastatic cholangiocarcinoma who developed acquired resistance to ivosidenib. After disease progression, one patient developed an oncogenic IDH2 mutation, and the second patient acquired a secondary IDH1 D279N mutation. To characterize the putative IDH1 resistance mutation, cells expressing the double-mutant were generated. In vitro, IDH1 R132H/D279N produces (R)-2HG less efficiently than IDH1 R132H. However, its binding to ivosidenib is impaired and it retains the ability to produce (R)-2HG and promote cellular transformation in the presence of ivosidenib. The irreversible mutant IDH1 inhibitor LY3410738 binds and blocks (R)-2HG production and cellular transformation by IDH1 R132H/D279N. These resistance mechanisms suggest that IDH1-mutated cholangiocarcinomas remain dependent on (R)-2HG even after prolonged ivosidenib treatment. Sequential mutant IDH inhibitor therapy should be explored as a strategy to overcome acquired resistance to mutant IDH inhibitors.

The Molecular Pathogenesis and Targeted Therapies for Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a group of malignancies of the bile ducts with high mortality rates and limited treatment options. In the past decades, remarkable efforts have been dedicated toward elucidating the specific molecular signaling pathways and oncogenic loops driving cholangiocarcinogenesis to ultimately develop more effective therapies. Despite some recent advances, an extensive intra- and inter-tumor heterogeneity together with a poorly understood immunosuppressive microenvironment significantly compromises the efficacy of available treatments. Here, we provide a concise review of the latest advances and current knowledge of the molecular pathogenesis of CCA focusing on clinically relevant aberrations as well as future research avenues.

Metabolic reprogramming in cholangiocarcinoma

Metabolic reprogramming is a hallmark of cancer and allows tumour cells to meet the increased energy demands required for rapid proliferation, invasion, and metastasis. Indeed, many tumour cells acquire distinctive metabolic and bioenergetic features that enable them to survive in resource-limited conditions, mainly by harnessing alternative nutrients. Several recent studies have explored the metabolic plasticity of cancer cells with the aim of identifying new druggable targets, while therapeutic strategies to limit the access to nutrients have been successfully applied to the treatment of some tumours. Cholangiocarcinoma (CCA), a highly heterogeneous tumour, is the second most common form of primary liver cancer. It is characterised by resistance to chemotherapy and poor prognosis, with 5-year survival rates of below 20%. Deregulation of metabolic pathways have been described during the onset and progression of CCA. Increased aerobic glycolysis and glutamine anaplerosis provide CCA cells with the ability to generate biosynthetic intermediates. Other metabolic alterations involving carbohydrates, amino acids and lipids have been shown to sustain cancer cell growth and dissemination. In this review, we discuss the complex metabolic rewiring that occurs during CCA development and leads to unique nutrient addiction. The possible role of therapeutic interventions based on metabolic changes is also thoroughly discussed.

The current state of molecular profiling in gastrointestinal malignancies

This is a review of the current state of molecular profiling in gastrointestinal (GI) cancers and what to expect from this evolving field in the future. Individualized medicine is moving from broad panel testing of numerous genes or gene products in tumor biopsy samples, identifying biomarkers of prognosis and treatment response, to relatively noninvasive liquid biopsy assays, building on what we have learned in our tumor analysis and growing into its own evolving predictive and prognostic subspecialty. Hence, the field of GI precision oncology is exploding, and this review endeavors to summarize where we are now in preparation for the journey ahead.

An Insight into the Novel Immunotherapy and Targeted Therapeutic Strategies for Hepatocellular Carcinoma and Cholangiocarcinoma

Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) constitute highly malignant forms of primary liver cancers. Hepatocellular and bile duct carcinogenesis is a multiplex process, caused by various genetic and epigenetic alterations, the influence of environmental factors, as well as the implication of the gut microbiome, which was undervalued in the previous years. The molecular and immunological analysis of the above malignancies, as well as the identification of the crucial role of intestinal microbiota for hepatic and biliary pathogenesis, opened the horizon for novel therapeutic strategies, such as immunotherapy, and enhanced the overall survival of cancer patients. Some of the immunotherapy strategies that are either clinically applied or under pre-clinical studies include monoclonal antibodies, immune checkpoint blockade, cancer vaccines, as well as the utilization of oncolytic viral vectors and Chimeric antigen, receptor-engineered T (CAR-T) cell therapy. In this current review, we will shed light on the recent therapeutic modalities for the above primary liver cancers, as well as on the methods for the enhancement and optimization of anti-tumor immunity.

Diagnostic performance of edited 2HG MR spectroscopy of central glioma in the clinical environment

OBJECTIVE

Oncometabolite D-2-hydroxyglutarate (2HG) is pooled in isocitrate dehydrogenase (IDH)-mutant glioma cells. Detecting 2HG by MR spectroscopy (MRS) has been proven viable in the last decade but has not entirely found its way into the clinical routine. This study aimed to explore the adoption of 2HG MRS while acknowledging factors that influence its performance in the clinical environment.

METHODS

Thirty-nine MR spectra were acquired and reported prospectively in patients with suspected glioma using a 3 T system with Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) sequence utilizing averaged free induction decay (FID) signals. Postprocessing and evaluation of spectra were performed with jMRUI and LCModel. 2HG concentration estimates, 2HG/Cr ratio, together with quality measures, including Cramér-Rao lower bounds (CRLBs), full-width at half-maximum (FWHM) values, and signal-to-noise ratio (SNR) were calculated using LCModel. Immunohistochemistry and genomic analysis results used as a ground truth were available for 15 patients.

RESULTS

The threshold for test positivity was set according to the ROC curve at 1 mM. Calculated sensitivity was 57.14% (95% CI 0.20-0.88), specificity 87.5% (95% CI 0.46-0.99), positive predictive value 80%, and negative predictive value 70%. Overall diagnostic accuracy was 73.33% (95% CI 0.45-0.92). The 2HG/Cr ratio with the cutoff value 0.085 significantly improved sensitivity and overall diagnostic accuracy [85.71%, 95% CI 0.42-1.00 and 86.67%, (95% CI 0.60-0.98), respectively].

CONCLUSION

Multiple factors compromising spectral quality in the clinical adoption of edited 2HG MRS resulted in diminished sensitivity but clinically acceptable specificity. Furthermore, the 2HG/Cr ratio performs better than the sole 2HG concentration estimate in the pre-operative setting.

ESMO Scale for Clinical Actionability of Molecular Targets driving targeted treatment in patients with cholangiocarcinoma

Purpose: Treatment options for advanced cholangiocarcinoma are limited and prognosis is poor. Cholangiocarcinomas are highly heterogeneous at the molecular level, with divergent patterns between intrahepatic and extrahepatic forms, intrahepatic being particularly rich in actionable alterations. We compared survival in patients with advanced cholangiocarcinoma harboring alterations matched to targeted drugs, with patients harboring non-actionable alterations. Experimental design: Patients with cholangiocarcinoma treated between 2011 and 2020 at one institution, with available molecular analyses, were retrospectively reviewed. Genomic alteration actionability was classified according to the ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) and correlated with efficacy endpoints. Results: Of 327 patients included, 78.9% had intrahepatic cholangiocarcinoma, 97.9% had received chemotherapy for metastatic disease. Actionable molecular alterations per ESCAT were identified in 184 patients (56.3%), including IDH1 mutations and FGFR2 fusions (23.1% and 8.0% of intrahepatic cholangiocarcinoma patients, respectively). Median overall survival in 50 patients with ESCAT I-IV alterations who received matched therapy (48 with intrahepatic cholangiocarcinoma) was 22.6 months (95%CI:20.1-32.8), compared to 14.3 months (95%CI:11.9-18.1) in 130 patients without actionable ESCAT alterations (HR=0.58, 95%CI:0.40-0.85; P=0.005). Among patients receiving matched targeted therapy, median progression-free survival was longer for patients with alterations classified as ESCAT I-II compared to ESCAT III-IV (5.0 versus 1.9 months; HR=0.36, 95%CI:0.15-0.87; P=0.02). Conclusions: ESCAT represents a tool to guide clinicians in fine-tuning use of molecular profiling data to choose matched targeted therapies. Our data demonstrate that targeted treatment administered per alteration actionability according to ESCAT is associated with improved survival in cholangiocarcinoma, particularly in ESCAT I-II intrahepatic cholangiocarcinoma.

Liver Transplantation for Unresectable Intrahepatic Cholangiocarcinoma: The Role of Sequencing Genetic Profiling

Intrahepatic cholangiocarcinoma (iCCA) is a rare and aggressive primary liver tumor, characterized by a range of different clinical manifestations and by increasing incidence and mortality rates even after curative treatment with radical resection. In recent years, growing attention has been devoted to this disease and some evidence supports liver transplantation (LT) as an appropriate treatment for intrahepatic cholangiocarcinoma; evolving work has also provided a framework for better understanding the genetic basis of this cancer. The aim of this study was to provide a clinical description of our series of patients complemented with Next-Generation Sequencing genomic profiling. From 1999 to 2021, 12 patients who underwent LT with either iCCA or a combined hepatocellular and cholangiocellular carcinoma (HCC-iCCA) were included in this study. Mutations were observed in gene activating signaling pathways known to be involved with iCCA tumorigenesis (KRAS/MAPK, P53, PI3K-Akt/mTOR, cAMP, WNT, epigenetic regulation and chromatin remodeling). Among several others, a strong association was observed between the Notch pathway and tumor size (point-biserial rhopb = 0.93). Our results are suggestive of the benefit potentially derived from molecular analysis to improve our diagnostic capabilities and to devise new treatment protocols, and eventually ameliorate long-term survival of patients affected by iCCA or HCC-iCCA.

A review of molecularly targeted therapy in biliary tract carcinoma: what is the next step?

Patients with unresectable biliary tract carcinomas (BTCs) have a poor prognosis with a median overall survival of fewer than 12 months following systemic chemotherapy. In recent years, the identification of distinct molecular alterations with corresponding targeted therapies is modifying this therapeutic algorithm. The aim of this review is to present an overview of targeted therapy for BTCs, describing published available data and potential future challenges in ongoing trials. From clinicaltrials.gov online database all ongoing trials for BTCs (any stage) was examinated in July 2021, and data regarding study design, disease characteristics and type of treatments were registered. Oncogenic-driven therapy (targeted therapy) was investigated in 67 trials. According to research, 15 ongoing trials (22.4%) are investigating fibroblast growth factor (FGF) receptor (FGFR)-inhibitors in BTCs. Three (18.7%) are open-label randomized multicenter phase 3 trials, 8 (50%) are single-arm phase two trials, and 4 (25%) are phase one studies. Twelve (17.9%) clinical trials dealt with isocitrate dehydrogenase (IDH) 1/2 targeting therapy either in combination with cisplatin (Cis) and gemcitabine (Gem) as first-line treatment for BTCs or in monotherapy in patients with IDH1 mutant advanced malignancies, including cholangiocarcinoma (CCA). Nine (13.4%) clinical trials tested human epidermal growth factor receptor (HER) 2 targeting therapy. Four (44.4%) studies are phase I trials, two (22.2%) are phase I/II trials, and three (33.3%) phase II trials. Rare molecular alterations in BTCs, such as anaplastic lymphoma kinase (ALK), c-ros oncogene1 receptor tyrosine kinase (ROS1), and v-RAF murine sarcoma viral oncogene homologue B1 (BRAF), are also under investigation in a few trials. Forty-four clinical trials (17.2%) are investigating not oncogenic-driven multitarget therapy like multireceptor tyrosin kinase inhibitors and antiangiogenetic agents. In conclusion, this review shows that BTCs management is experiencing important innovations, especially in biomarker-based patient selection and in the new emerging therapeutic approach. Many ongoing trials could answer questions regarding the role of molecular inhibitors leading to new therapeutic frontiers for molecular subcategories of BTCs.

Quality of Life and Symptom Management in Advanced Biliary Tract Cancers

Biliary tract carcinomas (BTCs) account for less than 1% of all cancers but are increasing in incidence. Prognosis is poor for BTC patients, with 5-year survival rates of less than 10%. While chemotherapy has been the mainstay treatment for patients with advanced BTC, immunotherapy and targeted therapies are being evaluated in numerous clinical trials and rapidly incorporated into clinical practice. As patients with BTC have reduced health-related quality of life (HRQoL) due to both tumor- and treatment-related symptoms, it is important for clinicians to recognize and manage these symptoms early. This review will highlight the anticipated complications from BTC and its systemic treatment, as well as their effects on HRQoL.

Druggable molecular alterations in bile duct cancer: potential and current therapeutic applications in clinical trials

Introduction: Cholangiocarcinomas (CCA) are rare tumors that are associated with a variety of molecular alterations. Many of these alterations are now actionable using drugs currently in development, and CCA may be a perfect example of application of a precision oncology approach. However, development of drugs in CCA faces the challenge of targeting rare alterations in a rare disease.Areas covered: In this review, we present the current data on targeted therapies in development for CCA, focusing on IDH1, FGFR2, BRAF, and HER2 alterations. We also discuss rationale for targeting other alterations, currently without specific development in CCA. We searched PubMed and google scholar in February 2021 for relevant articles and presentation in recent congress regarding the literature on molecular alterations, drugs in cholangiocarcinomas and biliary tract cancers.Expert opinion: Despite a strong rationale and promising early results, applying a precision oncology approach in CCA for everyday patients is still exposed to significant challenges: obtaining the molecular portrait of these tumors due to difficulties with biopsy access, complexities of drug development in subgroups of these relatively rare tumors, and sub-optimal access to drugs outside clinical trials.

Current challenges to underpinning the genetic basis for cholangiocarcinoma

AREAS COVERED

This review provides an overview regarding the current scenario and knowledge of the CCA genomic landscape and the potentially actionable molecular aberrations in each CCA subtype.

EXPERT OPINION

The establishment and advances of high-throughput methodologies applied to genetic and epigenetic profiling are changing many cancer types' therapeutic landscape , including CCA.The large body of data generated must be interpreted appropriately and eventually implemented in clinical practice. The following advancements toward precision medicine in CCA management will require designing better clinical trials with improved methods to stratify biliary tumor patients.

IDH inhibitors in advanced cholangiocarcinoma: Another arrow in the quiver?

Cholangiocarcinomas (CCAs) are a heterogenous group of hepatobiliary tumors with poor prognosis and limited therapeutic options. In the last decade, the advent of genomic profiling has led to the identification of several putative actionable aberrations in CCAs, and genomic characterization is playing an increasing role in the management of these malignancies. Thus, a wide number of targetable mutations are currently under investigation, and early studies on this approach in CCAs have been recently presented or published. Among these, isocitrate dehydrogenase (IDH) mutations have been reported in approximately 15-20% of intrahepatic cholangiocarcinoma (iCCA) patients, while these aberrations are considered to be less frequent in perihilar CCA (pCCA), distal CCA (dCCA), and gallbladder cancer. Of note, the recent findings of the ClarIDHy phase III trial add to mounting evidence showing the potential advantages of molecularly targeted therapies in CCA, on the basis of a benefit in previously treated IDH1-mutant patients receiving ivosidenib versus placebo. However, although the results of this trial showed a statistically significant improvement in progression-free survival and overall survival for IDH-mutant CCAs treated with ivosidenib, several questions regarding the real impact of IDH inhibitors in this setting remain open. In this review, we will provide an overview on the biological rationale behind the use of IDH inhibitors in CCA patients and current clinical implications of these molecularly targeted agents. The recently published results of the ClarIDHy - as well as ongoing clinical trials in this setting - are highlighted and critically discussed.