Targeted Therapy in Biliary Tract Cancers

A comparison of diagnostic utility of new endoscopic scraper combined cell block method and conventional brush catheter for biliary tract cancer

Background/Aims

The sensitivities of endoscopic trans-papillary pathologic diagnosis of biliary tract cancer (BTC) are unsatisfactory. Recently, the diagnostic utility of the endoscopic scraper device, Trefle for biliary stricture has been reported. The Trefle can be guided to the target biliary stricture over the guidewire and is as easy to use as the conventional brush catheter (CBC). This study evaluated the efficacy and safety of Trefle-assisted tissue acquisition combined cell block method and CBC cytology for biliary strictures due to BTCs.

Methods

We retrospectively reviewed consecutive patients with biliary strictures in whom CBC cytology or Trefle-assisted tissue acquisition under endoscopic retrograde cholangiopancreatography was performed for suspected BTCs from January 2015 to June 2022 at our institution.

Results

173 patients (CBC group; n = 55, Trefle group; n = 118) were enrolled in this study. The sensitivity, specificity, and accuracy of CBC cytology for BTC were 68.3%/100%/76.4%. On the other hand, the sensitivity, specificity, and accuracy of Trefle-assisted tissue acquisition for BTC were 93.7%/95.7%/94.1%, showing superior sensitivity (p < 0.001) and accuracy (p = 0.002) compared to that of CBC.

Conclusions

Compared to CBC cytology, Trefle-assisted tissue acquisition has superior diagnostic performance while maintaining procedural simplicity and is considered useful for diagnosing malignant biliary stricture.

Role of chemotherapeutic drugs in immunomodulation of cancer

The immune system has a variety of potential effects on a tumor microenvironment and the course of chemotherapy may vary according to that. Anticancer treatments can encourage the release of unwanted signals from senescent tumor cells or the removal of immune-suppressive cells, which can lead to immune system activation. Hence, by inducing an immunological response and conversely making cancer cells more vulnerable to immune attack, chemotherapeutic agents can destroy cancer cells. Furthermore, chemotherapy can activate anticancer immune effectors directly or indirectly by thwarting immunosuppressive pathways. Therefore, in this review, we discuss how chemotherapeutic agents take part in immunomodulation and the molecular mechanisms underlying them. We also focus on the importance of carefully addressing the conflicting effects of chemotherapy on immune responses when developing successful combination treatments based on chemotherapy and immune modulators.

The Hallmarks of Liver Fluke Related Cholangiocarcinoma: Insight into Drug Target Possibility

Cholangiocarcinoma (CCA) is a malignant tumor of the biliary tree that is classified into three groups based on its anatomic location: intrahepatic (iCCA), perihilar (pCCA), and distal (dCCA). Perihilar CCA is the most common type and accounts for 50-60% of CCA cases. It is followed by distal CCA and then intrahepatic CCA that account for 20-30% and 10-20% of cases, respectively. This chapter discusses the hallmarks of liver fluke related CCA and explores insights into drug target possibilities.

The role of tumor-infiltrating lymphocytes in cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common primary liver cancer and associated with a dismal prognosis due to the lack of an efficient systemic therapy. In contrast to other cancers, new immunotherapies have demonstrated unsatisfactory results in clinical trials, underlining the importance of a deeper understanding of the special tumor microenvironment of CCA and the role of immune cells interacting with the tumor. Tumor-infiltrating lymphocytes (TILs) are an important component of the adaptive immune system and the foundation of current immunotherapy. Therefore, the aim of this systemic review is to summarize the current literature focusing on the proportions and distribution, molecular pathogenesis, prognostic significance of TILs and their role in immunotherapy for CCA patients.

In CCA, CD8+ and CD4+ T lymphocytes represent the majority of TILs and are mostly sequestered around the cancer cells. CD20+ B lymphocytes and Natural Killer (NK) cells are less frequent. In contrast, Foxp3+ cells (regulatory T cells, Tregs) are observed to infiltrate into the tumor. In the immune microenvironment of CCA, cancer cells and stromal cells such as TAMs, TANs, MSDCs and CAFs inhibit the immune protection function of TILs by secreting factors like IL-10 and TGF-β. With respect to molecular pathogenesis, the Wnt/-catenin, TGF-signaling routes, aPKC-i/P-Sp1/Snail Signaling, B7-H1/PD-1Pathway and Fas/FasL signaling pathways are connected to the malignant potential and contributed to tumor immune evasion by increasing TIL apoptosis. Distinct subtypes of TILs show different prognostic implications for the long-term outcome in CCA. Although there are occasionally conflicting results, CD8+ and CD4+ T cells, and CD20+ B cells are positively correlated with the oncological prognosis of CCA, while a high number of Tregs is very likely associated with worse overall survival. TILs also play a major role in immunotherapy for CCA.

In summary, the presence of TILs may represent an important marker for the prognosis and a potential target for novel therapy, but more clinical and translational

data is needed to fully unravel the importance of TILs in the treatment of CCA.

Systemic Treatment for Metastatic Biliary Tract Cancer: State of the Art and a Glimpse to the Future

Recent years have seen some breakthroughs in the therapeutic landscape of advanced biliary tract cancer (BTC). Firstly, a better understanding of the molecular background of BTC has led to important improvements in the management of these hepatobiliary malignancies, with the advent of targeted agents representing an unprecedented paradigm shift, as witnessed by the FDA approval of pemigatinib and infigratinib for FGFR2-rearranged and ivosidenib in IDH1-mutant cholangiocarcinoma. In addition, several novel treatments are under assessment, including immune checkpoint inhibitors and combination chemotherapies. In the current review, we provide an overview of systemic treatment for metastatic BTC, summarizing recent clinical data on chemotherapy as well as the main results of targeted therapies and immunotherapy.

Analysis of the efficacy and prognostic factors of PD-1 inhibitors in advanced gallbladder cancer

Background

Gallbladder cancer (GBC) is highly malignant, its early diagnosis is difficult, and the 5-year survival rate is less than 5%. For patients with advanced GBC (GBCa), combined chemotherapy, radiotherapy, targeted therapy, and immunotherapy are needed to improve the overall survival (OS) rate of patients.

Methods

Data were collected from 53 patients with GBCa who had volunteered to receive programmed death protein-1 (PD-1)-based treatment at the First Affiliated Hospital of Nanjing Medical University from February 2018 to February 2021. Statistical analysis of the collected data, including Kaplan-Meier method, log-rank test, Cox proportional hazard regression model and other methods.

Results

The objective response rates (ORRs) and disease control rates (DCRs) of 53 participants 3 months after receiving immunotherapy were 30.2% and 79.2%, respectively. The ORRs and DCRs of the combined treatment group were higher than those of the camrelizumab group (CG) (P<0.05). The DCRs of the camrelizumab plus apatinib group (CAG) at 3 and 6 months were 90.9% and 45.5% (P=0.003), respectively, while the DCRs at 3 and 6 months of the camrelizumab plus chemotherapy group (CCG) were 85.7% and 71.4% (P=0.450), respectively. After treatment, there were statistically significant differences before and after CA199 for each group (P<0.05). The median progression-free survival (mPFS) of the 53 participants was 7 months, and the median overall survival (mOS) was 12 months. The mPFS and mOS of the CAG and the CCG were greater than those in the CG (6 vs. 3 months, P<0.001, 12 vs. 8 months, P=0.019; 9 vs. 3 months, P<0.001, 13 vs. 8 months, P<0.001, respectively). A total of 16 cases had grade 1 or 2 adverse events, and 3 cases had grade 3 and higher adverse events.

Conclusions

For GBCa patients, PD-1 combined with targeted therapy or chemotherapy is more effective than immunotherapy alone. The targeted therapy group has more obvious early effects on the disease control rate, and combined chemotherapy can achieve sustained effects, providing new ideas for the future GBCa application of immune, targeted, and chemotherapy sequential therapy.

WEE1 inhibition reverses trastuzumab resistance in HER2-positive cancers

BACKGROUND

To date, many efforts have been made to understand the resistance mechanism of trastuzumab in human epidermal growth factor receptor 2 (HER2)-positive breast and gastric cancer. However, there is still a huge unmet medical need for patients with trastuzumab resistance.

METHODS

In our study, we generated four trastuzumab-resistant (HR) cancer cell lines from ERBB2-amplified gastric and biliary tract cancer cell lines (SNU-216, NCI-N87, SNU-2670, and SNU-2773).

RESULTS

Here, we found higher PD-L1 expression in trastuzumab-resistant (HR) HER2-positive cancer cells than in parental cells, and blocking PD-L1 reversed the resistance to trastuzumab in HR cells. Trastuzumab upregulated PD-L1 expression via NF-κB activation in both parental and HR cells, however, led to DNA damage only in parental cells. The WEE1 inhibitor adavosertib, which downregulates PD-L1 expression, enhanced trastuzumab efficacy by blocking BRCA1-CMTM6-PD-L1 signals and the HER2-CDCP-1-SRC axis. Additionally, the levels of galectin-9, CD163, FoxP3, and CTLA-4 were diminished by blocking WEE1 in the presence of human PBMCs in vitro.

CONCLUSION

Taken together, the strategy of co-targeting HER2 and WEE1 could overcome resistance to trastuzumab in HER2-positive cancers, supporting further clinical development in HER2-positive cancer patients.

High expression of PSMC2 promotes gallbladder cancer through regulation of GNG4 and predicts poor prognosis

Gallbladder cancer (GBC) is a common malignant tumor of the biliary tract, which accounts for 80-95% of biliary tumors worldwide, and is the leading cause of biliary malignant tumor-related death. This study identified PSMC2 as a potential regulator in the development of GBC. We showed that PSMC2 expression in GBC tissues is significantly higher than that in normal tissues, while high PSMC2 expression was correlated with more advanced tumor grade and poorer prognosis. The knockdown of PSMC2 in GBC cells induced significant inhibition of cell proliferation, colony formation and cell motility, while the promotion of cell apoptosis. The construction and observation of the mice xenograft model also confirmed the inhibitory effects of PSMC2 knockdown on GBC development. Moreover, our mechanistic study recognized GNG4 as a potential downstream target of PSMC2, knockdown of which could aggravate the tumor suppression induced by PSMC2 knockdown in vitro and in vivo. In conclusion, for the first time, PSMC2 was revealed as a tumor promotor in the development of GBC, which could regulate cell phenotypes of GBC cells through the interaction with GNG4, and maybe a promising therapeutic target in GBC treatment.

Molecular Features and Targeted Therapies in Extrahepatic Cholangiocarcinoma: Promises and Failures

Biliary tract cancers (BTCs) include a heterogenous group of aggressive malignancies with limited therapeutic options. According to their anatomical location, these hepatobiliary tumors are usually classified into intrahepatic cholangiocarcinoma (iCCA), extrahepatic cholangiocarcinoma (eCCA), and gallbladder cancer (GBC). Unfortunately, BTCs are often diagnosed when already metastatic, and although the advent of genomic sequencing has led to a deeper understanding of iCCA pathogenesis, very little data are currently available about the molecular landscape of eCCA. Moreover, despite novel systemic treatments emerging in BTC, the grim prognosis of eCCA patients has not changed in the past decade, and no targeted therapies have been approved so far. The aim of the current review is to provide an overview regarding molecular features and potential targeted therapies in eCCA, together with novel therapeutic approaches and future directions of translational and clinical research on this highly aggressive disease that poses many unanswered questions.

Translating Biomarkers of Cholangiocarcinoma for Theranosis: A Systematic Review

Cholangiocarcinoma (CCA) is a rare disease with poor outcomes and limited research efforts into novel treatment options. A systematic review of CCA biomarkers was undertaken to identify promising biomarkers that may be used for theranosis (therapy and diagnosis). MEDLINE/EMBASE databases (1996-2019) were systematically searched using two strategies to identify biomarker studies of CCA. The PANTHER Go-Slim classification system and STRING network version 11.0 were used to interrogate the identified biomarkers. The TArget Selection Criteria for Theranosis (TASC-T) score was used to rank identified proteins as potential targetable biomarkers for theranosis. The following proteins scored the highest, CA9, CLDN18, TNC, MMP9, and EGFR, and they were evaluated in detail. None of these biomarkers had high sensitivity or specificity for CCA but have potential for theranosis. This review is unique in that it describes the process of selecting suitable markers for theranosis, which is also applicable to other diseases. This has highlighted existing validated markers of CCA that can be used for active tumor targeting for the future development of targeted theranostic delivery systems. It also emphasizes the relevance of bioinformatics in aiding the search for validated biomarkers that could be repurposed for theranosis.

Pretreatment Prognostic Nutritional Index (PNI) as a Prognostic Factor in Patients with Biliary Tract Cancer: A Meta-Analysis

OBJECTIVE

Many reports have shown that the prognostic nutritional index (PNI) is associated with the clinical outcomes of patients with biliary tract cancer (BTC), with the results being inconsistent. We therefore comprehensively evaluated the prognostic significance of the PNI in BTC by performing a meta-analysis.

METHODS

We identified relevant studies by searching PubMed, Embase, Web of Science and, the Cochrane Library. The combined hazard ratio (HR) and odds ratio (OR) with 95% confidence interval (CI) were used to evaluate the association between PNI and overall survival (OS) and the clinical characteristics of BTC.

RESULTS

We included seven studies with 1608 patients in this meta-analysis. The pretreatment low PNI correlated significantly with worse OS (HR = 1.65, 95%CI = 1.42-1.93, p < 0.001). In addition, the prognostic effect of PNI are reliable in different subgroups of ethnicity, sample size, histology, treatment, PNI cutoff, and cutoff determination. The low PNI was also related to poor differentiation (OR = 1.95, 95%CI = 1.34-2.85, p = 0.001) as well as higher T stage (OR = 2.51, 95%CI = 1.69-3.74, p < 0.001) in BTC.

CONCLUSION

The low PNI is significantly associated with inferior prognosis of patients with BTC and aggressive clinical factors. The PNI could be applied as an independent prognostic marker for patients with BTC.

Risk Stratification in Advanced Biliary Tract Cancer: Validation of the A.L.A.N. Score

Background

In addition to the clinical parameters, immune-inflammatory markers have emerged as prognostic factors in patients with advanced biliary tract cancer (ABC). The recently proposed A.L.A.N. score combines both in an easily applicable manner. The aim of this study was to perform the first external evaluation of this score.

Methods

All patients from our clinical registry unit who had unresectable ABC underwent first-line chemotherapy from 2006 to 2018 and met the inclusion criteria of the original study were included (n =  74). The A.L.A.N. score comprises the following parameters: actual neutrophil count, lymphocyte-to-monocyte ratio, albumin, and neutrophil-to-lymphocyte ratio (A.L.A.N.). Univariate and multivariate hazard regression analyses were performed to evaluate the score's parameters regarding overall survival (OS). The concordance index (C-index) and integrated Brier score (IBS) were calculated to evaluate the score's predictive performance.

Results

Low, intermediate, and high A.L.A.N. scores corresponded to median OS of 21.9, 11.4, and 4.3 months, respectively, resulting in a significant risk stratification (log-rank p=0.017). In multivariate analysis, a high-risk A.L.A.N. score remained an independent predictor of poor survival (p=0.016). Neutrophil-to-lymphocyte ratio was not a significant factor for poor OS in the analyses in the cohort. The score's ability to predict individual patient survival was only moderate with a C-index of 0.63.

Conclusions

The A.L.A.N. score can be used to identify risk groups with a poor prognosis prior to the start of chemotherapy. However, the ability of the score to predict individual patient outcome was only moderate; thus, it may only serve as a minor component in the complex interdisciplinary discussion.

Clinicopathological features and survival of gallbladder squamous cell carcinoma: analysis of 121 cases

PURPOSE

The aim of the present study is to promote deeper pathological and clinical understanding of gallbladder squamous cell carcinoma (GBSCC) and provide new evidence for its diagnosis and treatment.

METHODS

Two cases of GBSCC from the First Affiliated Hospital of Guangxi Medical University were collected. A comprehensive analysis was conducted based upon these 2 cases and another 119 GBSCC cases from the literature. Survival analysis was performed using the Kaplan-Meier method.

RESULTS

Among all the patients, GBSCC was frequently diagnosed in older women with a mean age of 62.8 years old. Abdominal pain was the most common symptom. The majority of GBSCC cases were combined with cholelithiasis. Keratinization was frequently observed microscopically. Among 90 cases with histology data, most showed high or, high-moderate differentiation (60%, 54/90). More cases were diagnosed in advanced TNM stages (85.4%, 82/96). In 73 cases, the follow-up time was 0.5-125 months, with a mean survival time 47.3 months and a median survival time of 12 months. Survival analysis indicated that patients with polypoid lesions (P = 0.047) and receiving R0 radical operation (P < 0.001) had better prognoses.

CONCLUSION

Given the scarcity and implicit clinical manifestations of GBSCC, early diagnosis is challenging. The key to better survival is a radical operation with no remaining lesion.

Potential candidate treatment agents for targeting of cholangiocarcinoma identified by gene expression profile analysis

Cholangiocarcinoma (CCA) remains to be a major health problem in several Asian countries including Thailand. The molecular mechanism of CCA is poorly understood. Early diagnosis is difficult, and at present, no effective therapeutic drug is available. The present study aimed to identify the molecular mechanism of CCA by gene expression profile analysis and to search for current approved drugs which may interact with the upregulated genes in CCA. Gene Expression Omnibus (GEO) was used to analyze the gene expression profiles of CCA patients and normal subjects. Using the Kyoto Encyclopedia of Genes and Genomes (KEGG), gene ontology enrichment analysis was also performed, with the KEGG pathway analysis indicating that pancreatic secretion, protein digestion and absorption, fat digestion and absorption, and glycerolipid metabolism may serve important roles in CCA oncogenesis. The drug signature database (DsigDB) was used to search for US Food and Drug Administration (FDA)-approved drugs potentially capable of reversing the effects of the upregulated gene expression in CCA. A total of 61 antineoplastic and 86 non-antineoplastic drugs were identified. Checkpoint kinase 1 was the most interacting with drug signatures. Many of the targeted protein inhibitors that were identified have been approved by the US-FDA as therapeutic agents for non-antineoplastic diseases, including cimetidine, valproic acid and lovastatin. The current study demonstrated an application for bioinformatics analysis in assessing the potential efficacy of currently approved drugs for novel use. The present results suggest novel indications regarding existing drugs useful for CCA treatment. However, further in vitro and in vivo studies are required to support the current predictions.

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.

Genotyping and mRNA profiling reveal actionable molecular targets in biliary tract cancers

Biliary tract cancer (BTC) represents a heterogeneous disease with dismal outcome. Herein, we examined genotype and angiogenesis features in BTC. We applied genotyping (Sanger, qPCR, 101-gene panel NGS), mRNA relative quantification methods, and β-catenin immunohistochemistry in 84 FFPE BTC (55 gallbladder [GBC], 14 intrahepatic [ICC], 15 extrahepatic [ECC] carcinomas). We identified 541 mutations in 68 (81%) tumors. Top mutated genes were CTNNB1 (36%); PTEN (33%); TP53 (31%); PIK3R1 (29%); PIK3CA (13%); BRCA2 and KRAS (12%); BRCA1 (11%). Six GBCs were hypermutated [hm] displaying a distinct mutational pattern. Mutations in TP53 and PI3K, Wnt and RAS components were prevalent among non-hypermutated tumors. All hmGBCs carried mutations in BRCA2 and other homologous recombination repair (HRR) genes, in PD1, but not in CTNNB1 and KRAS. None of the pathogenic BRCA2 p.D2723G and BRCA1 p.Q563* and c.5266dupC was present at frequencies expected for germline mutations. We observed copy gains (>6 copies) in EGFR (9% of informative tumors), PRKAR1A (7%), PIK3CA (6%), ERBB2 (5%) and MET (4%). TP53 mutations were prevalent in GBC (P<0.001) and PRKAR1A copy gains in ICC (P=0.007). PTEN was frequently co-mutated with CTNNB1 (P<0.001). Unrelated to CTNNB1 mutations, nuclear β-catenin was detected in 45% of tumors, among them in 5/6 hmGBC. We observed strong mRNA expression correlation of the two neuropilins (NRP1 and NRP2) with each other (Spearman's rho 0.59) and with the endothelin receptor (NRP2 rho 0.66; NRP2 rho 0.51), and between VEGFA and its receptors (FLT1 rho 0.49; KDR rho 0.45). All PIK3CA mutated tumors expressed endothelin 1 mRNA (P=0.010). Most tumors expressing nuclear β-catenin were negative for VEGFC (P=0.009) and FLT4 (P=0.002) mRNA expression. In conclusion, we confirmed the presence of known genomic aberrations in BTC and different genotypes between BTC subsets. Novel findings are the coexistence of PI3K and WNT pathway gene alterations in BTC, their association with angiogenesis, and the hypermutated GBCs with HRR gene mutations, all of which may be considered for new treatment options in this difficult to treat disease.

HER2/HER3 pathway in biliary tract malignancies; systematic review and meta-analysis: a potential therapeutic target?

Human epidermal growth factor receptor 2 (HER2) overexpression and amplification have been reported as predictive markers for HER2-targeted therapy in breast and gastric cancer, whereas human epidermal growth factor receptor 3 (HER3) is emerging as a potential resistance factor. The aim of this study was to perform a systematic review and meta-analysis of the HER2 and HER3 overexpression and amplification in biliary tract cancers (BTCs). An electronic search of MEDLINE, American Society of Clinical Oncology (ASCO), European Society of Medical Oncology Congress (ESMO), and American Association for Cancer Research (AACR) was performed to identify studies reporting HER2 and/or HER3 membrane protein expression by immunohistochemistry (IHC) and/or gene amplification by in situ hybridization (ISH) in BTCs. Studies were classified as "high quality" (HQ) if IHC overexpression was defined as presence of moderate/strong staining or "low quality" (LQ) where "any" expression was considered positive. Of 440 studies screened, 40 met the inclusion criteria. Globally, HER2 expression rate was 26.5 % (95 % CI 18.9-34.1 %). When HQ studies were analyzed (n = 27 studies), extrahepatic BTCs showed a higher HER2 overexpression rate compared to intrahepatic cholangiocarcinoma: 19.9 % (95 % CI 12.8-27.1 %) vs. 4.8 % (95 % CI 0-14.5 %), respectively, p value 0.0049. HER2 amplification rate was higher in patients selected by HER2 overexpression compared to "unselected" patients: 57.6 % (95 % CI 16.2-99 %) vs. 17.9 % (95 % CI 0.1-35.4 %), respectively, p value 0.0072. HER3 overexpression (4/4 HQ studies) and amplification rates were 27.9 % (95 % CI 9.7-46.1 %) and 26.5 % (one study), respectively. Up to 20 % of extrahepatic BTCs appear to be HER2 overexpressed; of these, close to 60 % appear to be HER2 amplified, while HER3 is overexpressed or amplified in about 25 % of patients. Clinical relevance for targeted therapy should be tested in prospective clinical trials.

Genomic Profiling of Biliary Tract Cancers and Implications for Clinical Practice

OPINION STATEMENT

Biliary tract cancers are relatively uncommon, have an aggressive disease course and a dismal clinical outcome. Until recently, there have been very few clinical advances in the management of these patients and gemcitabine-based chemotherapy has been the only widely accepted systemic therapy. The advent of next generation sequencing technologies can potentially change the treatment paradigm of this disease. Targeted therapy directed against actionable mutations and identification of molecular subsets with distinct prognostic significance is now feasible in clinical practice. Mutation profiling has highlighted the genomic differences between the intra, extrahepatic cholangiocarcinoma, and gallbladder cancer. The mutational spectrum of intrahepatic cholangiocarcinoma differs according to geographic location and ethnicity. There is a higher incidence of chromatin modulating gene mutations in Western patients as compared with Asian patients with liver fluke-associated cholangiocarcinoma. KRAS and p53 mutations are associated with an aggressive disease prognosis while FGFR mutations may signify a relatively indolent disease course of intrahepatic cholangiocarcinoma. FGFR and IDH mutations have promising agents in clinical trials at this time. An estimated 15 % of gallbladder cancers have Her2/neu amplification and can be targeted by trastuzumab. On the other hand, an estimated 10-15 % of cholangiocarcinomas have DNA repair mutations and may be candidates for immune therapies with checkpoint inhibitors. The promise of targeted therapies for biliary tract cancers can be fulfilled with well-designed, prospective, and multi-center clinical trials.

Resistance Mechanism against Trastuzumab in HER2-Positive Cancer Cells and Its Negation by Src Inhibition

Trastuzumab in combination with chemotherapy is the standard of care for patients with human epidermal growth factor receptor 2 (HER2)-positive breast and gastric cancers. Several resistance mechanisms against anti-HER2 therapy have been proposed. Src activation has been suggested to be responsible for the resistance of HER2-positive breast cancer. In our study, we generated four trastuzumab-resistant (HR) cancer cell lines from HER2-amplified gastric and biliary tract cancer cell lines (SNU-216, NCI-N87, SNU-2670, and SNU-2773). Elevated Src phosphorylation was detected in SNU2670HR and NCI-N87HR cell lines, but not in SNU216HR or SNU2773HR cell lines. In SNU216HR and SNU2773HR cell lines, phospho-FAK (focal adhesion kinase) was elevated. Bosutinib as a Src inhibitor suppressed growth, cell-cycle progression, and migration in both parental and HR cell lines. Specifically, Src interacted with FAK to affect downstream molecules such as AKT, ERK, and STAT3. Bosutinib showed more potent antitumor effects in Src-activated HR cell lines than parental cell lines. Taken together, this study suggests that Src inhibition may be an effective measure to overcome trastuzumab resistance in HER2-positive cancer. Mol Cancer Ther; 16(6); 1145-54. ©2017 AACR.

Efficacy and safety of chemotherapy with or without targeted therapy in biliary tract cancer: A meta-analysis of 7 randomized controlled trials

The systematic treatment based on gemcitabine plus cisplatin is recommended as the current standard chemotherapy for unresectable or metastatic biliary tract cancers. However, the exact benefits from the recognized regime are still dismal. We thus elicit this study in an attempt to analyze whether targeted therapy coupled with various chemotherapy could produce improvement of survival benefits. The clinical trials were searched electronically from databases till July 2016 published in English and Chinese. Nine hundred and sixty-four patients from 7 trials were identified in our analysis. The overall analysis achieved a significantly higher overall response rate (ORR) among the patients treated with targeted drugs plus chemotherapy than chemotherapy alone (OR=1.87; 95% CI: 1.37-2.57; P=0.000), but failed in the overall progression-free survival (PFS) [mean difference (MD)=0.63; 95% CI:-0.45-1.72; P=0.26] and overall survival (OS) (MD=-0.67; 95% CI:-2.54-1.20; P=0.49). In the sub analysis, better ORR was obtained with the addition of EGFR (OR=1.75; 95% CI: 1.20-2.56; P=0.004) and VEGFR (OR=2.5; 95% CI: 1.28-4.87; P=0.007) targeted therapy. Furthermore, the sub analysis of EGFR target showed an significant improvement on PFS (MD=1.36; 95% CI: 0.29-2.43; P=0.01). No significant differences were observed in the incidences of neutropenia (OR=1.37; 95% CI: 0.89-2.12), thrombocytopenia (OR=1.40; 95% CI: 0.83-2.39), anemia (OR=1.21; 95% CI: 0.62-2.38), peripheral neuropathy (OR=1.52; 95% CI: 0.81-2.88), increased AST/ALT (OR=1.40; 95% CI: 0.82-2.39) as well as fatigue (OR=1.65; 95% CI: 0.96-2.84) in either of the treatment groups. In conclusion, better ORR associated with chemotherapy combined with targeted therapy (both targeting EGFR and VEGF) is found in the present meta-analysis without the cost of increased unacceptable toxicities, but regretfully not for the OS. The sub-analysis of targeting EGFR instead of VEGF obtains a superior PFS. Otherwise, there is no statistically significant difference in the overall PFS between the combination regime and chemotherapy alone. Given the paucity of favorable data, we need further studies to characterize optimal targeted agents to confirm the potential value to biliary tract cancer.

Multidisciplinary management of intrahepatic cholangiocarcinoma: Current approaches

Intrahepatic cholangiocarcinoma (ICC) is a common primary hepatic tumor. However, its outcomes are usually worse than those of hepatocellular carcinoma owing to its non-specific presentation and detection at an advanced stage. The most widely used serum marker, carbohydrate antigen 19-9, is non-specific. Furthermore, imaging studies rarely identify any pathognomonic features. Surgery is the only treatment option that offers a chance of long-term survival. However, the resectability rate is low owing to the high frequencies of intrahepatic metastases, peritoneal carcinomatosis, or extrahepatic metastases. Surgical treatment should be tailored according to the macroscopic classification of ICC (e.g. mass-forming, periductal infiltrating, and intraductal growth types) because it reflects the tumor's dissemination pattern. Although lymph node metastasis is a negative prognostic factor, the importance and extent of lymph node dissection is still controversial. To improve patient survival, liver transplantation is considered in some patients with unresectable ICC, especially in those with an insufficient remnant liver volume. Minimally invasive procedures, including laparoscopic and robotic liver resection, have been tested and achieved comparable outcomes to conventional surgery in preliminary studies. No randomized trials have confirmed the efficacy of adjuvant chemotherapy in ICC, and several trials have evaluated molecular-targeted agents as monotherapy or in combination with cytotoxic chemotherapy. Multidisciplinary approaches are necessary to improve the outcomes of ICC.

Intrahepatic cholangiocarcinoma: current perspectives

Intrahepatic cholangiocarcinoma (ICC) is the second most common malignancy arising from the liver. ICC makes up about 10% of all cholangiocarcinomas. It arises from the peripheral bile ducts within the liver parenchyma, proximal to the secondary biliary radicals. Histologically, the majority of ICCs are adenocarcinomas. Only a minority of patients (15%) present with resectable disease, with a median survival of less than 3 years. Multidisciplinary management of ICC is complicated by large differences in disease course for individual patients both across and within tumor stages. Risk models and nomograms have been developed to more accurately predict survival of individual patients based on clinical parameters. Predictive risk factors are necessary to improve patient selection for systemic treatments. Molecular differences between tumors, such as in the epidermal growth factor receptor status, are promising, but their clinical applicability should be validated. For patients with locally advanced disease, several treatment strategies are being evaluated. Both hepatic arterial infusion chemotherapy with floxuridine and yttrium-90 embolization aim to downstage locally advanced ICC. Selected patients have resectable disease after downstaging, and other patients might benefit because of postponing widespread dissemination and biliary obstruction.

Cocktail treatment with EGFR-specific and CD133-specific chimeric antigen receptor-modified T cells in a patient with advanced cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is one of the most fatal malignant tumors with increasing incidence, mortality, and insensitivity to traditional chemo-radiotherapy and targeted therapy. Chimeric antigen receptor-modified T cell (CART) immunotherapy represents a novel strategy for the management of many malignancies. However, the potential of CART therapy in treating advanced unresectable/metastatic CCA is uncharted so far.

CASE PRESENTATION

In this case, a 52-year-old female who was diagnosed as advanced unresectable/metastatic CCA and resistant to the following chemotherapy and radiotherapy was treated with CART cocktail immunotherapy, which was composed of successive infusions of CART cells targeting epidermal growth factor receptor (EGFR) and CD133, respectively. The patient finally achieved an 8.5-month partial response (PR) from the CART-EGFR therapy and a 4.5-month-lasting PR from the CART133 treatment. The CART-EGFR cells induced acute infusion-related toxicities such as mild chills, fever, fatigue, vomiting and muscle soreness, and a 9-day duration of delayed lower fever, accompanied by escalation of IL-6 and C reactive protein (CRP), acute increase of glutamic-pyruvic transaminase and glutamic-oxalacetic transaminase, and grade 2 lichen striatus-like skin pathological changes. The CART133 cells induced an intermittent upper abdominal dull pain, chills, fever, and rapidly deteriorative grade 3 systemic subcutaneous hemorrhages and congestive rashes together with serum cytokine release, which needed emergent medical intervention including intravenous methylprednisolone.

CONCLUSIONS

This case suggests that CART cocktail immunotherapy may be feasible for the treatment of CCA as well as other solid malignancies; however, the toxicities, especially the epidermal/endothelial damages, require a further investigation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01869166 and NCT02541370 .

Molecular profiling of biliary tract cancer: a target rich disease

Biliary tract cancers (BTCs) are relatively uncommon orphan tumors that have an aggressive disease course and a poor clinical outcome. Surgery is the only curative treatment, but most patients present with advanced disease and therefore have a limited survival. Gemcitabine and cisplatin based chemotherapy has been the only widely accepted standard systemic therapy regimen in these patients but these tumors can be chemoresistant, further complicating their management. In recent times, there has been considerable research in the genetics of BTC and with the advent of new, advanced technologies like next-generation sequencing (NGS) we are achieving a greater understanding of its disease biology. With the help of NGS, we have now been able to identify actionable mutations such as in the isocitrate dehydrogenase 1 (IDH1), FGFR2, BRAF and HER2/neu genes for targeted therapeutics and correlate the genetic variations with distinct clinical prognoses. This recent genetic information has the potential to make precision medicine a part of routine clinical practice for the management of BTC patients.

Genomic Alterations in Biliary Tract Cancer Using Targeted Sequencing

Background: Biliary tract cancers (BTCs) are rare and heterogeneous group of tumors classified anatomically into intrahepatic and extrahepatic bile ducts and gallbladder adenocarcinomas. Patient-derived tumor cell (PDC) models with genome analysis can be a valuable platform to develop a method to overcome the clinical barrier on BTCs. Material and Methods: Between January 2012 and June 2015, 40 BTC patients’ samples were collected. PDCs were isolated and cultured from surgical specimens, biopsy tissues, or malignant effusions including ascites and pleural fluid. Genome analysis using targeted panel sequencing as well as digital multiplexed gene analysis was applied to PDCs as well as primary tumors. Results: Extrahepatic cholangiocarcinoma (N = 15, 37.5%), intrahepatic cholangiocarcinoma (N = 10, 25.0%), gallbladder cancer (N = 14, 35.0%), and ampulla of Vater cancer (N = 1, 2.5%) were included. We identified 15 mutations with diverse genetic alterations in 19 cases of BTC from primary tumor specimens. The most common molecular alterations were in TP53 (8/19, 42.1%), including missense mutations such as C242Y, E285K, G112S, P19T, R148T, R248Q, and R273L. We also detected two NRAS mutations (G12C and Q61L), two KRAS mutations (G12A and G12S), two ERBB2 mutations (V777L and pM774delinsMA) and amplification, and three PIK3CA mutations (N345K, E545K, and E521K). PDC models were successfully established in 27 of 40 samples (67.5%), including 22/24 from body fluids (91.7%) and 5/16 from tissue specimens (31.3%). Conclusions: PDC models are promising tools for uncovering driver mutations and identifying rational therapeutic strategies in BTC. Application of this model is expected to inform clinical trials of drugs for molecular-based targeted therapy.

Clinical aspects and perspectives of erlotinib in the treatment of patients with biliary tract cancer

INTRODUCTION

Patients with non-resectable biliary tract cancer have a poor prognosis even if treated with systemic chemotherapy. One hope for improving treatment is through molecular biology and the characterization of specific cancer driving alterations followed by the design of targeted drugs. The epidermal growth factor receptor system is upregulated in many cancers and can be targeted by the protein kinase inhibitor erlotinib. Erlotinib has demonstrated a clinically applicable effect in pancreatic and lung cancer Areas covered: In this review, the author presents the published clinical data about erlotinib in biliary tract cancer. The data is interpreted with respect to its clinical value and in regards to its future development.

EXPERT OPINION

Erlotinib has low activity as a monotherapy, but has shown synergistic effects when combined with bevacizumab. The only phase III trial with erlotinib was negative, but suggested improved progression free survival in cholangiocarcinoma patients when added to gemcitabine and oxaliplatin. There is no clinical, radiological or molecular marker to guide therapy, but genomic profiling and basket or umbrella trials may be useful in identifying the subset of patients benefitting from erlotinib. Until this subgroup has been defined, erlotinib has no value to biliary tract cancer patients in the daily clinic.

Biliary Tract Cancer: Epidemiology, Radiotherapy, and Molecular Profiling

Biliary tract cancer, or cholangiocarcinoma, arises from the biliary epithelium of the small ducts in the periphery of the liver (intrahepatic) and the main ducts of the hilum (extrahepatic), extending into the gallbladder. The incidence and epidemiology of biliary tract cancer are fluid and complex. It is shown that intrahepatic cholangiocarcinoma is on the rise in the Western world, and gallbladder cancer is on the decline. Radiation therapy has emerged as an important component of adjuvant therapy for resected disease and definitive therapy for locally advanced disease. The emerging sophisticated techniques of imaging tumors and conformal dose delivery are expanding the indications for radiotherapy in the management of bile duct tumors. As we understand more about the molecular pathways driving biliary tract cancers, targeted therapies are at the forefront of new therapeutic combinations. Understanding the gene expression profile and mutational burden in biliary tract cancer allows us to better discern the pathogenesis and identify promising new developmental therapeutic targets.