Intrahepatic Cholangiocarcinoma: A Summative Review of Biomarkers and Targeted Therapies

Second-Line Chemotherapy for Intrahepatic Cholangiocarcinomas: What Is the Real Gain?

BACKGROUND

The presence of actionable alterations in advanced biliary tract cancer patients opened new therapeutic possibilities for second-line treatments. However, for around 60% of the patients, chemotherapy remains the only therapeutic option. The aim of our study was to evaluate outcomes and prognostic parameters in patients with intrahepatic cholangiocarcinomas treated with second-line chemotherapy.

METHODS

A total of 255 consecutive metastatic intrahepatic cholangiocarcinoma (ICC) patients were retrospectively reviewed and clinicopathologic and survival data were collected.

RESULTS

Fourty-four percent of ICC patients underwent second-line chemotherapy. In particular, younger ICC patients with better ECOG PS status, and with disease control after first-line chemotherapy were those who were treated with second-line treatments. Median progression-free survival in the patients treated with second-line chemotherapy was 3 months. Finally, the patients affected by intrahepatic cholangiocarcinoma with better ECOG PS, with prior surgical resection of the primary tumor, who responded to first-line chemotherapy, and had better progression-free survival with second-line chemotherapy, were associated with better outcomes in multivariate analysis.

CONCLUSIONS

Not all patients seem to benefit from second-line chemotherapy. To improve therapeutic decisions, performance status and disease control with first-line chemotherapy should lead to the decision on the usefulness of second-line treatments in advanced ICC patients.

IL-8 is a novel prometastatic chemokine in intrahepatic cholangiocarcinoma that induces CXCR2-PI3K/AKT signaling upon CD97 activation

Intrahepatic cholangiocarcinoma (ICC) is a rare but highly aggressive malignant tumor arising within the liver, with a 5-year survival rate of only 20-40% after surgery. The role of interleukin-8 (IL-8) in ICC progression remains elusive. A transcriptomic approach based on IL-8 stimulation first revealed significant upregulation of the prometastatic gene CD97 and key epithelial-mesenchymal transition (EMT) factors E-cadherin and vimentin. Immunohistochemistry of 125 ICC tissues confirmed the positive correlation between IL-8 and CD97. Multivariable Cox regression indicated that they are both independent predictors of ICC prognosis. Mechanistically, IL-8 treatment induced CD97 expression at 50 and 100 ng/ml in QBC-939 and QBE cells, respectively. Moreover, the induction of cell migration and invasion upon IL-8 treatment was attenuated by CD97 RNA interference, and the expression of EMT-associated genes was dramatically inhibited. To determine whether CXCR1 or CXCR2 are downstream effectors of IL-8, siCXCR2 was applied and shown to significantly attenuate the oncogenic effects of IL-8 by inhibiting the phosphorylation of PI3K/AKT. Finally, the induction of CD97 expression by the PI3K pathway was verified by treatment with the inhibitor LY294002. In vivo, the significant tumor growth and lung metastasis effects induced by intraperitoneal injection of IL-8 were greatly inhibited by silencing CD97 in nude mice. Collectively, the study presents a novel mechanism of the IL-8-CXCR2-PI3K/AKT axis in regulating CD97 expression, which leads to ICC metastasis mainly through EMT. The study may provide alternatives for targeting the tumor microenvironment in metastatic ICC.

Development and Validation of a Machine-Learning Model to Predict Early Recurrence of Intrahepatic Cholangiocarcinoma

BACKGROUND

The high incidence of early recurrence after hepatectomy for intrahepatic cholangiocarcinoma (ICC) has a detrimental effect on overall survival (OS). Machine-learning models may improve the accuracy of outcome prediction for malignancies.

METHODS

Patients who underwent curative-intent hepatectomy for ICC were identified using an international database. Three machine-learning models were trained to predict early recurrence (< 12 months after hepatectomy) using 14 clinicopathologic characteristics. The area under the receiver operating curve (AUC) was used to assess their discrimination ability.

RESULTS

In this study, 536 patients were randomly assigned to training (n = 376, 70.1%) and testing (n = 160, 29.9%) cohorts. Overall, 270 (50.4%) patients experienced early recurrence (training: n = 150 [50.3%] vs testing: n = 81 [50.6%]), with a median tumor burden score (TBS) of 5.6 (training: 5.8 [interquartile range {IQR}, 4.1-8.1] vs testing: 5.5 [IQR, 3.7-7.9]) and metastatic/undetermined nodes (N1/NX) in the majority of the patients (training: n = 282 [75.0%] vs testing n = 118 [73.8%]). Among the three different machine-learning algorithms, random forest (RF) demonstrated the highest discrimination in the training/testing cohorts (RF [AUC, 0.904/0.779] vs support vector machine [AUC, 0.671/0.746] vs logistic regression [AUC, 0.668/0.745]). The five most influential variables in the final model were TBS, perineural invasion, microvascular invasion, CA 19-9 lower than 200 U/mL, and N1/NX disease. The RF model successfully stratified OS relative to the risk of early recurrence.

CONCLUSIONS

Machine-learning prediction of early recurrence after ICC resection may inform tailored counseling, treatment, and recommendations. An easy-to-use calculator based on the RF model was developed and made available online.

Toward Precision Perioperative Therapy in GI Malignancies

PURPOSE

The term precision oncology typically refers to molecularly guided therapies against cancer. Less appreciated but also critically important is molecular identification of patients with resectable disease who are most likely to benefit from perioperative drugs, and tailored selection of such drugs. We call this idea precision perioperative therapy. Over the past several years, use of precision perioperative approaches for patients with localized GI cancers has expanded in clinical trials and practice. Here, we summarize the status of the field and highlight areas of future innovation.

METHODS

Using PubMed, we reviewed articles published from 2017 to 2023 in English. We used search terms "adjuvant," "perioperative," "neoadjuvant," and "precision medicine" for various types of GI malignancies. Information about ongoing clinical trials was accessed through ClinicalTrials.gov, accessed January 2023.

RESULTS

Paradigms such as minimal residual disease detection via circulating tumor DNA and perioperative immunotherapy in lieu of chemotherapy for mismatch repair-deficient disease may lead to reduced toxicity and improved long-term outcomes in select populations. Molecularly targeted drugs that have shown activity against metastatic disease may also hold promise in the curable setting.

CONCLUSION

The field is very much in development, but emerging data demonstrate early promise. We are optimistic that ongoing research efforts will increasingly bring precision perioperative therapy to patients with resectable GI malignancies.

Impact of Staging Concordance and Downstaging After Neoadjuvant Therapy on Survival Following Resection of Intrahepatic Cholangiocarcinoma: A Bayesian Analysis

INTRODUCTION

Concordance between clinical and pathological staging, as well as the overall survival (OS) benefit associated with neoadjuvant therapy (NAT) remain ill-defined. We sought to determine the impact of staging accuracy and NAT downstaging on OS among patients with intrahepatic cholangiocarcinoma (ICC).

METHODS

Patients treated for ICC between 2010 and 2018 were identified using the National Cancer Database. A Bayesian approach was applied to estimate NAT downstaging. OS was assessed relative to staging concordant/overstaged disease treated with upfront surgery, understaged disease treated with upfront surgery, no downstaging, and downstaging after NAT.

RESULTS

Among 3384 patients, 2904 (85.8%) underwent upfront surgery, whereas 480 (14.2%) received NAT and 85/480 (18.4%) were downstaged. Patients with cT3 (odds ratio [OR] 2.12, 95% confidence interval [CI] 1.34-3.34), cN1 (OR 2.47, 95% CI 1.71-3.58) disease, and patients treated at high-volume facilities (OR 1.63, 95% CI 1.13-2.36) were more likely to receive NAT (all p < 0.05). Median OS was 40.1 months (95% CI 38.6-43.4). Patients with cT1-2N1 (NAT: 31.5 months vs. upfront surgery: 22.4 months; p = 0.04) and cT3-4N1 (NAT: 27.8 months vs. upfront surgery: 14.4 months; p = 0.01) disease benefited most from NAT. NAT downstaging decreased the risk of death among patients with cT3-4N1 disease (hazard ratio [HR] 0.35, 95% CI 0.15-0.82). In contrast, understaged patients with cT1-2N0/X (HR 2.15, 95% CI 1.83-2.53) and cT3-4N0/X (HR 1.71, 95% CI 1.06-2.74) disease treated with upfront surgery had increased risk of death.

CONCLUSIONS

Patients with N1 ICC treated with NAT demonstrated improved OS compared with upfront surgery. Downstaging secondary to NAT conferred survival benefits among patients with cT3-4N1 versus upfront surgery. NAT should be considered in ICC patients with advanced T disease and/or nodal metastases.

Developments in FGFR and IDH inhibitors for cholangiocarcinoma therapy

INTRODUCTION

Cholangiocarcinoma (CCA) is an uncommon malignancy originating from epithelial cells of the biliary tract. Regardless of the site of origin within the biliary tree, CCAs are generally aggressive with a poor survival. Surgical resection remains the only chance for cure, yet a majority of patients are not surgical candidates at presentation. Unfortunately, systemic therapies are often ineffective and complicated by side effects. As such, more effective targeted therapies are required in order to improve survival.

AREA COVERED

Genetic analysis of CCA has allowed for a better understanding of the genomic landscape of CCA. Isocitrate dehydrogenase (IDH) and fibroblast growth factor receptor (FGFR) mutations have emerged as the most promising molecular targets for CCA. Inhibitors of IDH and FGFR have proven to have therapeutic benefit with an acceptable safety profile. However, patients often develop resistance rendering the therapy ineffective.

EXPERT OPINION

Understanding the molecular pathways of IDH and FGFR may lead to a better understanding of the mechanisms of resistance. Thus, novel therapies may be developed to improve the efficacy of these therapies. Developing novel biomarkers may improve patient selection and further enhance effectiveness of targeted therapies.

Surgical Aspects of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is a rare and aggressive malignancy. It originates from the bile ducts and is the second most common primary cancer of the liver. Surgery is considered the only curative treatment of ICC, offering the best chance for long-term survival. The purpose of this article is to review the available literature on ICC, with a focus on the various aspects of the surgical care in this potentially lethal malignancy.

Precision Medicine in Biliary Tract Cancer

Precision medicine has become a dominant theme in the treatment of biliary tract cancers (BTCs). Although prognosis remains poor, technologies for improved molecular characterization along with the US Food and Drug Administration approval of several targeted therapies have changed the therapeutic landscape of advanced BTC. The hallmark of BTC oncogenesis is chronic inflammation of the liver and biliary tract regardless of the anatomical subtype. Subtypes of BTC correspond to distinct molecular characteristics, making BTC a molecularly heterogenous collection of tumors. Collectively, up to 40% of BTCs harbor a potentially targetable molecular abnormality, and the National Comprehensive Cancer Network guidelines recommend molecular profiling for all patients with advanced BTC. Use of circulating tumor DNA, immunohistochemistry, and next-generation sequencing continues to expand the utility for biomarker-driven management and molecular monitoring of BTC. Improving outcomes using biomarker-agnostic treatment for nontargetable tumors also remains a priority, and combinational treatment strategies such as immune checkpoint inhibition plus chemotherapy hold promise for this subgroup of patients.

Ferroptosis in Intrahepatic Cholangiocarcinoma: IDH1105GGT Single Nucleotide Polymorphism Is Associated With Its Activation and Better Prognosis

Objectives

Intrahepatic cholangiocarcinoma (ICC) has a dismal prognosis and often demonstrates an anti-apoptotic landscape, which is a key step to chemotherapy resistance. Isocitrate dehydrogenase 1 or 2 (IDH1-2)-mutated ICCs have been described and associated with better prognosis. Ferroptosis is a regulated iron-mediated cell death induced by glutathione peroxidase 4 (GPX4) inhibition, and may be triggered pharmacologically. GPX4 is overexpressed in aggressive cancers, while its expression is inhibited by IDH1^R132C mutation in cell lines. We investigated tissue expression of ferroptosis activation markers in ICC and its correlation with clinical-pathological features and IDH1-2 status.

Materials and Methods

We enrolled 112 patients who underwent hepatic resection or diagnostic liver biopsy for ICC. Immunostaining for transferrin-receptor 1 and GPX4, and Pearls’ stain for iron deposits were performed to evaluate ferroptosis activation. Immunostaining for STAT3 was performed to study pro-inflammatory and anti-apoptotic landscape. Main IDH1-2 mutations were investigated in 90 cases by real-time polymerase chain reaction.

Results

GPX4 overexpression was seen in 79.5% of cases and related to poor histological prognostic factors (grading and perineural and vascular invasion; p < 0.005 for all) and worse prognosis (OS p = 0.03; DFS p = 0.01). STAT3 was expressed in 95.5% of cases, confirming the inflammation-related anti-apoptotic milieu in ICC, and directly related to GPX4 expression (p < 0.0001). A high STAT3 expression correlated to a worse prognosis (OS p = 0.02; DFS p = 0.001). Nearly 12% of cases showed IDH1^105GGT single nucleotide polymorphism, which was never described in ICC up to now, and was related to lower tumor grade (p < 0.0001), longer overall survival (p = 0.04), and lower GPX4 levels (p = 0.001).

Conclusion

Our study demonstrates for the first time that in most inflammatory ICCs ferroptosis is not active, and its triggering is related to IDH1-2 status. This supports the possible therapeutic role of ferroptosis-inducer drugs in ICC patients, especially in drug-resistant cases.

YTHDF1 promotes intrahepatic cholangiocarcinoma progression via regulating EGFR mRNA translation

BACKGROUND AND AIM

Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive disease with the underlying mechanisms poorly understood. YTHDF1, an N⁶ -methyladenosine (m⁶ A) reader protein, has important physiological functions in regulation of tumor development. However, the effect of YTHDF1 on ICC progression remains unknown yet.

METHODS

The expression level of YTHDF1 in human ICC tissue was examined in The Cancer Genome Atlas database and our cohort. The role of YTHDF1 was detected using two human ICC cell lines in vitro. An ICC tumorigenesis mouse model was established via hydrodynamic transfection of AKT/YAP plasmids. m⁶ A sequencing, RNA immunoprecipitation sequencing, and RNA sequencing were carried out to explore the mechanism of YTHDF1 modulating ICC progression.

RESULTS

Here, we find that YTHDF1 is upregulated in ICC and associated with shorter survival of ICC patients. Depletion of YTHDF1 inhibits cell proliferation, migration, and invasion, while overexpression of wild-type YTHDF1, but not m⁶ A reader domain mutant YTHDF1, significantly enhances tumor cell growth and aggressive abilities in vitro. Moreover, overexpression of YTHDF1 promotes the AKT/YAP transfection-induced orthotopic ICC tumorigenesis and progression in vivo. Mechanistically, we identify that YTHDF1 regulates the translation of epidermal growth factor receptor (EGFR) mRNA via binding m⁶ A sites in the 3'-UTR of EGFR transcript, thus leading to aberrant activities of downstream signal pathways that impact tumor progression.

CONCLUSIONS

Our data uncover the oncogenic function and m⁶ A reader-dependent mechanism of YTHDF1 in regulation of ICC progression. Restricting abnormal oncogenic mRNA translation by targeting YTHDF1 may be a novel and promising strategy for ICC treatment.

Up-to-Date Pathologic Classification and Molecular Characteristics of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive primary liver malignancy with an increasing incidence worldwide. Recently, histopathologic classification of small duct type and large duct type iCCA has been introduced. Both these types of tumors exhibit differences in clinicopathological features, mutational profiles, and prognosis. Small duct type iCCA is composed of non-mucin-producing cuboidal cells, whereas large duct type iCCA is composed of mucin-producing columnar cells, reflecting different cells of origin. Large duct type iCCA shows more invasive growth and poorer prognosis than small duct type iCCA. The background liver of small duct type iCCA often shows chronic liver disease related to hepatitis B or C viral infection, or alcoholic or non-alcoholic fatty liver disease/steatohepatitis, in contrast to large duct type iCCA that is often related to hepatolithiasis and liver fluke infection. Cholangiolocarcinoma is a variant of small duct type iCCA composed of naïve-looking cuboidal cells forming cords or ductule-like structures, and shows better prognosis than the conventional small duct type. Fibrous tumor stroma, one of the characteristic features of iCCA, contains activated fibroblasts intermixed with innate and adaptive immune cells. The types of stroma (mature versus immature) are related to tumor behavior and prognosis. Low tumor-infiltrating lymphocyte density, KRAS alteration, and chromosomal instability are related to immune-suppressive tumor microenvironments with resistance to programmed death 1/ programmed death ligand 1 blockade. Data from recent large-scale exome analyses have revealed the heterogeneity in the molecular profiles of iCCA, showing that small duct type iCCA exhibit frequent BAP1, IDH1/2 hotspot mutations and FGFR2 fusion, in contrast to frequent mutations in KRAS, TP53, and SMAD4 observed in large duct type iCCA. Multi-omics analyses have proposed several molecular classifications of iCCA, including inflammation class and proliferation class. The inflammation class is enriched in inflammatory signaling pathways and expression of cytokines, while the proliferation class has activated oncogenic growth signaling pathways. Diverse pathologic features of iCCA and its associated multi-omics characteristics are currently under active investigation, thereby providing insights into precision therapeutics for patients with iCCA. This review provides the latest knowledge on the histopathologic classification of iCCA and its associated molecular features, ranging from tumor microenvironment to genomic and transcriptomic research.

Immunotherapy for Biliary Tract Cancer in the Era of Precision Medicine: Current Knowledge and Future Perspectives

Biliary tract cancers (BTC) represent a heterogeneous and aggressive group of tumors with dismal prognosis. For a long time, BTC has been considered an orphan disease with very limited therapeutic options. In recent years a better understanding of the complex molecular landscape of biology is rapidly changing the therapeutic armamentarium. However, while 40-50% of patients there are molecular drivers susceptible to target therapy, for the remaining population new therapeutic options represent an unsatisfied clinical need. The role of immunotherapy in the continuum of treatment of patients with BTC is still debated. Despite initial signs of antitumor-activity, single-agent immune checkpoint inhibitors (ICIs) demonstrated limited efficacy in an unselected population. Therefore, identifying the best partner to combine ICIs and predictive biomarkers represents a key challenge to optimize the efficacy of immunotherapy. This review provides a critical analysis of completed trials, with an eye on future perspectives and possible biomarkers of response.