Emerging molecular targets and therapy for cholangiocarcinoma

Programmed Cell Death Pathways in Cholangiocarcinoma: Opportunities for Targeted Therapy

Cholangiocarcinoma is a highly aggressive cancer arising from the bile ducts. The limited effectiveness of conventional therapies has prompted the search for new approaches to target this disease. Recent evidence suggests that distinct programmed cell death mechanisms, namely, apoptosis, ferroptosis, pyroptosis and necroptosis, play a critical role in the development and progression of cholangiocarcinoma. This review aims to summarize the current knowledge on the role of programmed cell death in cholangiocarcinoma and its potential implications for the development of novel therapies. Several studies have shown that the dysregulation of apoptotic signaling pathways contributes to cholangiocarcinoma tumorigenesis and resistance to treatment. Similarly, ferroptosis, pyroptosis and necroptosis, which are pro-inflammatory forms of cell death, have been implicated in promoting immune cell recruitment and activation, thus enhancing the antitumor immune response. Moreover, recent studies have suggested that targeting cell death pathways could sensitize cholangiocarcinoma cells to chemotherapy and immunotherapy. In conclusion, programmed cell death represents a relevant molecular mechanism of pathogenesis in cholangiocarcinoma, and further research is needed to fully elucidate the underlying details and possibly identify therapeutic strategies.

Silmitasertib plus gemcitabine and cisplatin first-line therapy in locally advanced/metastatic cholangiocarcinoma: A Phase 1b/2 study

BACKGROUND AND AIMS

This study aimed to investigate safety and efficacy of silmitasertib, an oral small molecule casein kinase 2 inhibitor, plus gemcitabine and cisplatin (G+C) versus G+C in locally advanced/metastatic cholangiocarcinoma.

APPROACH AND RESULTS

This work is a Phase 1b/2 study (S4-13-001). In Phase 2, patients received silmitasertib 1000 mg twice daily for 10 days with G+C on Days 1 and 8 of a 21-day cycle. Primary efficacy endpoint was progression-free survival (PFS) in the modified intent-to-treat population (defined as patients who completed at least one cycle of silmitasertib without dose interruption/reduction) from both phases (silmitasertib/G+C n = 55, G+C n = 29). The response was assessed by Response Evaluation Criteria in Solid Tumors v1.1. The median PFS was 11.2 months (95% confidence interval [CI], 7.6, 14.7) versus 5.8 months (95% CI, 3.1, not evaluable [NE]) ( p  = 0.0496); 10-month PFS was 56.1% (95% CI, 38.8%, 70.2%) versus 22.2% (95% CI, 1.8%, 56.7%); and median overall survival was 17.4 months (95% CI, 13.4, 25.7) versus 14.9 months (95% CI, 9.9, NE) with silmitasertib/G+C versus G+C. Overall response rate was 34.0% versus 30.8%; the disease control rate was 86.0% versus 88.5% with silmitasertib/G+C versus G+C. Almost all silmitasertib/G+C (99%) and G+C (93%) patients reported at least one treatment emergent adverse event (TEAE). The most common TEAEs (all grades) with silmitasertib/G+C versus G+C were diarrhea (70% versus 13%), nausea (59% vs. 30%), fatigue (47% vs. 47%), vomiting (39% vs. 7%), and anemia (39% vs. 30%). Twelve patients (10%) discontinued treatment because of TEAEs during the study.

CONCLUSIONS

Silmitasertib/G+C demonstrated promising preliminary evidence of efficacy for the first-line treatment of patients with locally advanced/metastatic cholangiocarcinoma.

Genomic alterations in cholangiocarcinoma: clinical significance and relevance to therapy

Improving the survival of patients with cholangiocarcinoma (CCA) has long proved challenging, although the treatment of this disease nowadays is on advancement. The historical invariability of survival outcomes and the limited number of agents known to be effective in the treatment of this disease has increased the number of studies designed to identify genetic targetable hits that can be efficacious for novel therapies. In this respect, the increasing feasibility of molecular profiling starting either from tumor tissue or circulating cell-free DNA (cfDNA) has led to an increased understanding of CCA biology. Intrahepatic CCA (iCCA) and extrahepatic CCA (eCCA) display different and typical patterns of actionable genomic alterations, which offer opportunity for therapeutic intervention. This review article will summarize the current knowledge on the genomic alterations of iCCA and eCCA, provide information on the main technologies for genomic profiling using either tumor tissue or cfDNA, and briefly discuss the main clinical trials with targeted agents in this disease.

HER2 Aberrations as a Novel Marker in Advanced Biliary Tract Cancer

HER2 aberrations have been reported as a novel biomarker in HER2-directed therapy or as a prognostic marker in various tumor types. However, in advanced biliary tract cancer (BTC), there have been few studies regarding HER2 aberrations as a biomarker. We analyzed 121 advanced BTC patients who had been treated with Gemcitabine/Cisplatin (GP) as a 1st line therapy between November 2019 and April 2021. Next-generation sequencing (NGS), namely, HER2 aberrations was performed in all patients. The TruSight™ Oncology 500 assay from Illumina was used for the NGS panel. Among 121 patients with advanced BTC, HER2 aberrations were observed in 18 patients (14.9%). For subtypes of HER2 aberrations, point mutation was observed in 5 patients (27.8%), gene amplification in 11 patients (61.1%), and both point mutation and gene amplification in 2 patients (11.1%). The frequency of HER2 aberrations was significantly different according to the primary tumor (p = 0.009). In gallbladder cancer, HER2 aberrations were observed at a relatively high frequency (36.4%). The tumor response to GP did not differ between patients with and without HER2 aberrations (33.3%, vs. 26.2%, respectively, p = 0.571). The median progression-free survival (PFS) to GP was 4.7 months (95% CI, 4.0 to 5.5 months) in patients with HER2 aberrations and 7.0 months (95% CI, 5.2 to 8.8 months) without HER2 aberrations (p = 0.776). The median overall survival (OS) was not reached and not reached in patients with and without HER2 aberrations (p = 0.739), respectively. The univariate analysis for PFS to GP and OS showed that HER2 aberrations were not an independent factor for survival. This study showed that the HER2 aberrations were observed in 14.9% of advanced BTC and were not an independent biomarker for survival.

CEACAM6 promotes cholangiocarcinoma migration and invasion by inducing epithelial-mesenchymal transition through inhibition of the SRC/PI3K/AKT signaling pathway

The immunoglobulin superfamily member carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is overexpressed in a wide variety of human cancer types, and is associated with tumor invasion and migration. The aim of the present study was to determine the role of CEACAM6 in cholangiocarcinoma (CCA) invasion and migration in vitro. The results showed that CEACAM6 was highly expressed in CCA tissues, and that the expression level of CEACAM6 was negatively associated with the degree of differentiation of CCA. Silencing CEACAM6 inhibited cell viability, invasion and migration but promoted cell apoptosis in a human CCA cell line (RBE). In addition, CEACAM6 knockdown decreased the expression of an antiapoptotic protein (Bcl-2), an interstitial cell marker (N-cadherin), extracellular matrix proteins (MMP-2 and MMP-9), a transcription factor helix protein (Twist-related protein 1), an intermediate tumor cell scaffold marker (vimentin), a protein involved in tumor nutrient vascular formation (VEGFA) and a tumorigenesis factor (intercellular cell adhesion molecule-1), but increased the expression of pro-apoptotic proteins (Bax, and cleaved caspases-3, -8 and -9) and an epithelial cell marker protein (E-cadherin). Furthermore, CEACAM6-small interfering RNA reduced the expression of the SRC/PI3K/AKT signaling transduction pathway. Taken together, these results suggested that CEACAM6 may be an epithelial-mesenchymal transition biomarker and a potential therapeutic target in human CCA.

Moving forward in the treatment of cholangiocarcinoma

Despite being the second most frequent primary liver tumor in humans, early diagnosis and treatment of cholangiocarcinoma (CCA) are still unsatisfactory. In fact, survival after 5 years is expected in less than one fourth of patients diagnosed with this disease. Rare incidence, late appearance of symptoms and heterogeneous biology are all factors contributing to our limited knowledge of this cancer and determining its poor prognosis in the clinical setting. Several efforts have been made in the last decades in order to achieve an improved classification/understanding with regard to the diverse CCA forms. Location within the biliary tree has helped to distinguish between intrahepatic, perihilar and distal CCA types. Sequence analysis contributed to identifying several characteristic genetic aberrations in CCA that may also serve as possible targets for therapy. Novel findings are expected to significantly improve the management of this malignancy in the near future. In this changing scenario our review focuses on the current and future strategies for CCA treatment. Both systemic and surgical treatments are discussed in detail. The results of the main studies in this field are reported, together with the ongoing trials. The current findings suggest that an integrated multidisciplinary approach to this malignancy would be helpful to improve its outcome.

Molecular heterogeneity in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous primary liver cancer, and currently there exist only a few options of targeted therapy. Histopathologically, iCCA is sub-classified according to morphology (mass forming type, periductal infiltrating type, and intraductal growing type) and histology (small duct type and large duct type). According to different histopathological types, clinical features such as risk factors and prognosis vary. Recent developments in genomic profiling have revealed several molecular markers for poor prognosis and activation of oncogenic pathways. Exploration of molecular characteristics of iCCA in each patient is a major challenge in a clinical setting, and there is no effective molecular-based targeted therapy. However, several recent studies suggested molecular-based subtypes with corresponding clinical and pathological features. Even though the subtypes have not yet been validated, it is possible that molecular features can be predicted based on clinicopathological characteristics and that this could be used for a more rational approach to integrative clinical and molecular subclassification and targeted therapy. In this review, we explored the genomic landscape of iCCA and attempted to find relevance between clinicopathologic and molecular features in molecular subtypes in several published studies. The results reveal future directions that may lead to a rational approach to the targeted therapy.

ERBB2 Pathway in Biliary Tract Carcinoma: Clinical Implications of a Targetable Pathway

BACKGROUND/AIMS

Current chemotherapy regimens for cholangiocarcinoma (CCA) yield poor outcomes, with a median overall survival of <12 months. Recent data on the genomic landscape of CCAs have created opportunities for targeted therapy. Yet, data regarding its efficacy are scarce. We aimed to describe the genomic landscape of a CCA patient cohort using next-generation sequencing (NGS), focusing on the ERBB/EFGR pathway and assessing response to anti-HER2 agents.

METHODS

Tissue samples of intrahepatic CCA (IHCC) and extrahepatic CCA (EHCC) underwent NGS for somatic aberrations. The clinical outcomes for patients treated with anti-HER2 agents were evaluated.

RESULTS

A total of 1,863 CCA cases (1,615 IHCCs and 248 EHCCs) underwent NGS, and they revealed a high prevalence of ERBB alterations (IHCC, 4.2%; EHCC, 9.7%). Among these, 23.8% of the IHCCs and 53.6% of the EHCCs had a point mutation in ERBB2, and 66.6% of the IHCCs and 41.2% of the EHCCs had ERBB copy number amplification. Three EHCC patients were diagnosed at our institute with ERBB/EGFR aberrations; 2 patients were treated with neratinib and 1 patient with a chemotherapy-trastuzumab combination. All 3 achieved disease stabilization and a clinical benefit. One patient underwent a liquid biopsy before and after 3 months of treatment, demonstrating disappearance of the ERBB2 clone and emergence of a Myc-mutated clone after treatment.

CONCLUSIONS

The genomic landscape of CCAs may harbor targetable alterations, especially in the ERBB/EGFR pathway. These alterations may have clinical significance in everyday practice.

Bioinformatics Analysis Identifies the Estrogen Receptor 1 (ESR1) Gene and hsa-miR-26a-5p as Potential Prognostic Biomarkers in Patients with Intrahepatic Cholangiocarcinoma

Background

Intrahepatic cholangiocarcinoma arises from the epithelial cells of the bile ducts and is associated with poor prognosis. This study aimed to use bioinformatics analysis to identify molecular biomarkers of intrahepatic cholangiocarcinoma and their potential mechanisms.

Material/Methods

MicroRNA (miRNA) and mRNA microarrays from GSE53870 and GSE32879 were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed miRNAs (DEMs) associated with prognosis were identified using limma software and Kaplan-Meier survival analysis. Predictive target genes of the DEMs were identified using miRWalk, miRTarBase, miRDB, and TargetScan databases of miRNA-binding sites and targets. Target genes underwent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Hub genes were analyzed by constructing the protein-protein interaction (PPI) network using Cytoscape. DEMs validated the hub genes, followed by construction of the miRNA-gene regulatory network.

Results

Twenty-five DEMs were identified. Fifteen DEMs were upregulated, and ten were down-regulated. Kaplan-Meier survival analysis identified seven upregulated DEMs and nine down-regulated DEMs that were associated with the overall survival (OS), and 130 target genes were selected. GO analysis showed that target genes were mainly enriched for metabolism and development processes. KEGG analysis showed that target genes were mainly enriched for cancer processes and some signaling pathways. Fourteen hub genes identified from the PPI network were associated with the regulation of cell proliferation. The overlap between hub genes and DEMs identified the estrogen receptor 1 (ESR1) gene and hsa-miR-26a-5p.

Conclusions

Bioinformatics analysis identified ESR1 and hsa-miR-26a-5p as potential prognostic biomarkers for intrahepatic cholangiocarcinoma.

Necroptosis in Cholangiocarcinoma

Necroptosis is a type of regulated cell death that is increasingly being recognized as a relevant pathway in different pathological conditions. Necroptosis can occur in response to multiple stimuli, is triggered by the activation of death receptors, and is regulated by receptor-interacting protein kinases 1 and 3 and mixed-lineage kinase domain-like, which form a regulatory complex called the necrosome. Accumulating evidence suggests that necroptosis plays a complex role in cancer, which is likely context-dependent and can vary among different types of neoplasms. Necroptosis serves as an alternative mode of programmed cell death overcoming apoptosis and, as a pro-inflammatory death type, it may inhibit tumor progression by releasing damage-associated molecular patterns to elicit robust cross-priming of anti-tumor CD8+ T cells. The development of therapeutic strategies triggering necroptosis shows great potential for anti-cancer therapy. In this review, we summarize the current knowledge on necroptosis and its role in liver biliary neoplasms, underlying the potential of targeting necroptosis components for cancer treatment.

Neoadjuvant chemotherapy with gemcitabine plus cisplatin followed by radical liver resection versus immediate radical liver resection alone with or without adjuvant chemotherapy in incidentally detected gallbladder carcinoma after simple cholecystectomy or in front of radical resection of BTC (ICC/ECC) - a phase III study of the German registry of incidental gallbladder carcinoma platform (GR)- the AIO/ CALGP/ ACO- GAIN-trial

BACKGROUND

Currently, complete surgical resection represents the only potentially curative treatment option for Biliary Tract Cancer (BTC) including Gallbladder Cancer (GBC). Even after curative resection, 5-year OS is only 20-40%. Gallbladder carcinoma is relatively rare, but still the fifth most common neoplasm of the digestive tract and even the most frequent cancer of the biliary system. Gallbladder carcinoma is suspected preoperatively in only 30% of all pts., while the majority of cases are discovered incidentally by the pathologist after cholecystectomy for a benign indication. For improving curative rates in BTC and GBC, early systemic therapy combined with radical resection seems to be a promising approach. The earliest moment to apply chemotherapy would be in front of radical surgery. The encouraging results of neoadjuvant/perioperative concepts in other malignancies provide an additional rationale to use this treatment in the early phase of GBC management and even ICC/ECC. Especially because data regarding pure adjuvant chemotherapy in BTC's are conflicting.

METHODS

This is a multicenter, randomized, controlled, open-label phase III study including pts. with incidentally discovered GBCs after simple cholecystectomy in front of radical liver resection and pts. with resectable/ borderline resectable cholangiocarcinomas (ICC/ ECC) scheduled to receive perioperative chemotherapy (Gemcitabine + Cisplatin 3 cycles pre- and post-surgery) or surgery alone followed by a therapy of investigator's choice. Primary endpoint is OS; secondary endpoints are PFS, R0-resection rate, toxicity, perioperative morbidity, mortality and QoL. A total of N = 333 patients with GBC or BTC will be included. Recruitment has started in August 2019.

DISCUSSION

The current proposed phase III GAIN study investigates whether induction chemotherapy followed by radical resection in ICC/ECC and re-resection in IGBC (and - if possible - postoperative chemotherapy) prolongs overall survival compared to radical surgery alone for incidental gallbladder carcinoma and primary resectable or borderline resectable cholangiocarcinoma. Utilizing a neoadjuvant approach including a second radical surgery will help to raise awareness for the necessity of radical surgery, especially second radical completion surgery in IGBC and improve the adherence to the guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03673072 from 17.09.2018. EudraCT number: 2017-004444-38 from 02.11.2017.

Significant response to anti-PD-1 based immunotherapy plus lenvatinib for recurrent intrahepatic cholangiocarcinoma with bone metastasis: A case report and literature review

INTRODUCTION

The prognosis for recurrent intrahepatic cholangiocarcinoma with bone metastasis remains dismal and its treatment poses a challenge for oncologists. To date, only 2 cases were reported in which pembrolizumab, an agent against programmed cell death protein-1 (PD-1), combined with chemotherapy led to a complete response. The safety and efficacy of nivolumab-based immunotherapy combined with lenvatinibin intrahepatic cholangiocarcinoma is unknown.

PATIENT CONCERNS

A 40-year-old female was identified as having a lesion of 7.0 cm in diameter in the right lobe of the liver. In addition, calculi in the main and left hepatic bile ducts as well as the gallbladder were found.

DIAGNOSIS

Based on the results of imaging studies and tumor biomarker level, the patient was initially diagnosed as having intrahepatic cholangiocellular carcinoma and cholelithiasis, after which surgery was performed. The pathological examination confirmed that the tumor was cholangiocarcinoma. Adjuvant chemotherapy was administered after surgery. However, the patient developed recurrent lesions at the 5th month after surgery, and the cholangiocarcinoma expanded to the right thoracic vertebral pedicle (T7-8) at the 6th month.

INTERVENTIONS

The patient underwent percutaneous microwave ablation after recurrence in the liver was identified. After that, the patient received nivolumab plus lenvatinib.

OUTCOMES

The lesions in the liver decreased in size and disappeared after treatment with nivolumab plus lenvatinib. Additionally, the metastases in the right thoracic vertebral pedicle were stable after 9 months of therapy.

LESSONS

Immunotherapy has revolutionized the treatment of non-small-cell lung cancer, melanoma, and advanced renal cell carcinoma. In this case, the patient achieved an excellent radiological and symptomatic response after receiving nivolumab plus lenvatinib combination therapy. Patients suffering from cholangiocarcinoma with dMMR status and a high tumor mutation burden (TMB) may have a consistent eutherapeutic effect with anti-PD-1-directed treatment.

Treatment and survival of resected and unresected distal cholangiocarcinoma: a nationwide study

Background: Population-based data on distal cholangiocarcinoma (DCC) from the Western world are not available, albeit essential to identify areas for improvement. This study investigated the incidence, treatment and outcomes, including time trends and predictors for survival, in a nationwide cohort of DCC. Methods: This is a retrospective cohort study of patients diagnosed with DCC (2009-2016) derived from the Netherlands Cancer Registry. Overall survival (OS) and its predictors were analyzed using Kaplan-Meier and Cox regression analysis. Time trends (2009-2012 versus 2013-2016) were assessed. Results: Overall, 1338 patients with DCC were included, with 1-, 3- and 5-year OS of 46%, 18%, and 11%. Incidence of DCC was 0.55-0.90 per 100.000 per year. Median OS was 10.4 months across all stages; 21.9 months for resected (n = 620, 46.3%), 6.7 months for unresected nonmetastatic (n = 445, 33.3%), and 3.6 months for metastatic DCC (n = 273, 20.4%) (p < .001). After resection, 30-day mortality was 4.8% and 90-day mortality 7.7%. Patients with metastatic DCC who received chemotherapy (n = 78, 28.6%) had a median OS of 8.2 versus 2.8 months for those not treated (p < .001). Over time, resection rates (53.6% to 61.7%, p = .008) and use of palliative chemotherapy in metastatic DCC (22.3% to 32.9%, p = .05) increased, without improvement in OS (10.3 vs 10.6 months, p = .55). Independent poor prognostic factors for OS in resected disease were increasing age, pT3/T4 stage, higher lymph node ratio, poor differentiation, and R1 resection. Conclusions: In a nationwide cohort of DCC, resection rates and the use of chemotherapy increased whereas OS remained stable at 10.4 months.

CXCR7 contributes to the aggressive phenotype of cholangiocarcinoma cells

Development of cholangiocarcinoma (CCA) is dependent on a cross-talk with stromal cells, which release different chemokines including CXCL12, that interacts with two different receptors, CXCR4 and CXCR7. The aim of the present study was to investigate the role of CXCR7 in CCA cells. CXCR7 is overexpressed by different CCA cell lines and in human CCA specimens. Knock-down of CXCR7 in HuCCT-1 cells reduced migration, invasion, and CXCL12-induced adhesion to collagen I. Survival of CCA was also reduced in CXCR7-silenced cells. The ability of CXCL12 to induce cell migration and survival was also blocked by CCX733, a CXCR7 antagonist. Similar effects of CXCR7 activation were observed in CCLP-1 cells and in primary iCCA cells. Enrichment of tumor stem-like cells by a 3D culture system resulted in increased CXCR7 expression compared to cells grown in monolayers, and genetic knockdown of CXCR7 robustly reduced sphere formation both in HuCCT-1 and in CCLP-1 cells. In HuCCT-1 cells CXCR7 was found to interact with β-arrestin 2, which was necessary to mediate CXCL12-induced migration, but not survival. In conclusion, CXCR7 is widely expressed in CCA, and contributes to the aggressive phenotype of CCA cells, inducing cell migration, invasion, adhesion, survival, growth and stem cell-like features. Cell migration induced by CXCR7 requires interaction with β-arrestin 2.

Molecular Diagnostics in the Neoplasms of the Pancreas, Liver, Gallbladder, and Extrahepatic Biliary Tract: 2018 Update

Pancreatic neoplasms, including ductal adenocarcinoma, solid pseudopapillary neoplasm, pancreatic endocrine neoplasms, acinar cell carcinoma, and pancreatoblastoma, are associated with different genetic abnormalities. Hepatic adenomas with beta-catenin exon 3 mutation are associated with a high risk of malignancy. Hepatic adenoma with arginosuccinate synthetase 1 expression or sonic hedgehog mutations are associated with a risk of bleeding. Hepatocellular carcinoma and choangiocarcinoma display heterogeneity at both morphologic and molecular levels Cholangiocellular carcinoma is most commonly associated with IDH 1/2 mutations.

Prognostic role of BAP-1 and PBRM-1 expression in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) has universally poor outcome, mainly due to its late clinical presentation. Identification of specific biomarkers and development of effective treatment are still urgently required. Mutations in PBRM-1 and BAP-1 genes, and the expression of S100P have been related to survival in ICC. miR-31 seems also to play important regulatory functions in ICC and it directly regulates BAP-1 expression in lung cancer. In this study, tissue expression of BAP-1, PBRM-1, S100P, and miR-31 was investigated in ICC and correlated with clinical-pathological features. Sixty-one consecutive patients who underwent curative hepatic resection for ICC were enrolled. None received any therapy prior to surgery. Immunostaining for BAP-1, PBRM-1, and S100P, and in situ hybridization for miR-31 were performed, using tissue microarray slides. A strong retained expression of BAP-1 and PBRM-1 was associated with a reduced overall (p = 0.04 and p = 0.002, respectively) and disease-free survival (p = 0.05 and p = 0.02, respectively). An overexpression of S100P was related to a reduced overall survival (p = 0.005). The multivariate analyses identified the presence of perineural invasion and the retained PBRM-1 expression as independent predictors of worse overall [p = 0.02, hazard ratio (HR) = 2.25 (1.16-4.39) and p = 0.001, HR = 3.13 (1.56-6.28), respectively] and disease-free survivals [p = 0.03, HR = 2.43 (1.09-5.4) and p = 0.03, HR = 2.51 (1.11-5.67), respectively]. An overexpression of S100P was predictive of a worse overall survival [p = 0.02, HR = 1.66 (1.08-2.55)]. High levels of miR-31 were significantly associated to a low expression of BAP-1 protein (p = 0.03). In ICC, a retained expression of BAP-1 and PBRM-1, and an overexpression of S100P are related to a poor prognosis.

"Clicking" Gene Therapeutics: A Successful Union of Chemistry and Biomedicine for New Solutions

The use of nucleic acid, DNA and RNA, based strategies to disrupt gene expression as a therapeutic is quickly emerging. Indeed, synthetic oligonucleotides represent a major component of modern gene therapeutics. However, the efficiency and specificity of intracellular uptake for nonmodified oligonucleotides is rather poor. Utilizing RNA based oligonucleotides as therapeutics is even more challenging to deliver, due to extremely fast enzymatic degradation of the RNAs. RNAs get rapidly degraded in vivo and demonstrate large off-target binding events when they can reach and enter the desired target cells. One approach that holds much promise is the utilization of "click chemistry" to conjugate receptor or cell specific targeting molecules directly to the effector oligonucleotides. We discuss here the applications of the breakthrough technology of CuAAC click chemistry and the immense potential in utilizing "click chemistry" in the development of new age targeted oligonucleotide therapeutics.

Correlation of LARP1 and E-cadherin expression with prognosis of intrahepatic cholangiocarcinoma

OBJECTIVE

The abnormal expression of LARP1 and E-cadherin (E-cad) is related to tumor occurrence and metastasis. Our study analyzed the expression of LARP1 and E-cad in intrahepatic cholangiocarcinoma (ICC) and investigated the prognostic value of the two proteins.

METHODS

Immunohistochemistry was performed to detect the expression of LARP1 and E-cad in 50 ICC clinical specimens with adjacent normal tissues and 20 normal bile duct tissues. In situ hybridization was performed to analyze the expression of LARP1 mRNA in all the specimens.

RESULTS

LARP1 protein and mRNA expression levels in ICC tumor tissues were significantly higher compared with corresponding adjacent normal tissues and normal epithelial tissues (P<0.01). E-cad protein expression in ICC tumor tissues was remarkably lower than that of the adjacent normal tissues and benign bile duct tissues (P<0.01). Correlation analysis demonstrated that LARP1 and E-cad expression levels were significantly related with the tumor-node-metastasis staging and lymph node metastasis (P<0.01), while no correlation was observed with patient age, gender, and tumor size. Moreover, Spearman rank correlation test revealed that LARP1 expression was negatively related to E-cad (P<0.05). More importantly, the patients with higher LARP1 expression or lower E-cad expression had a shorter overall survival postoperatively than those with LARP1 lower expression or E-cad higher expression. Multivariate analysis demonstrated that LARP1 and E-cad were both considered as important prognostic factors for survival time.

CONCLUSION

These findings suggest that the abnormal expression of LARP1 and E-cad showed a close relationship with the occurrence and metastasis of ICC, leading to poor prognosis indirectly.

Emerging molecular target antagonists for the treatment of biliary tract cancer

INTRODUCTION

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

Cholangiocarcinoma‑associated genes identified by integrative analysis of gene expression data

Cholangiocarcinoma (CCA) is characterized by delayed diagnosis and poor survival rate. Research efforts have focused on novel diagnostic technologies for this type of cancer. Transcriptomic microarray technology is a useful research strategy for investigating the molecular properties of CCA. The objective of the present study was to identify candidate biomarkers with high potential for clinical application in CCA using a meta‑analysis‑based approach. Gene expression profiles of CCA were downloaded from the Gene Expression Omnibus database for integrated analysis. All differentially expressed genes (DEGs) were analyzed by Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Protein‑protein interaction (PPI) networks were further constructed, hub proteins were identified and functional modules were extracted. Following integrated analysis of the seven eligible datasets (428 cases and 46 controls), a set of 1,080 DEGs was identified, including 710 upregulated and 370 downregulated genes. Functional enrichment analysis demonstrated that 'chromosome organization' was a significantly enriched GO term in the biological process category. 'DNA replication', 'influenza A', and 'lysosome' were the top three significantly enriched KEGG pathways. Furthermore, PPI network analysis indicated that the significant hub proteins were histone deacetylase 1, cullin‑associated NEDD8‑dissociated protein 1, ubiquitin D, early growth response protein 1 and glycogen synthase kinase 3β. The majority of these proteins are involved in CCA. These results provided a set of targets that may help researchers to clarify further the underlying mechanisms of CCA tumorigenesis.

Current status of liver transplantation for cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common liver cancer, and it is associated with a poor prognosis. CCA can be divided into intrahepatic, hilar, and distal. Despite the subtype, the median survival is 12-24 months without treatment. Liver transplantation (LT) is recognized worldwide as a curative option for hepatocellular carcinoma. On the other hand, the initial results for LT for CCA were very poor mainly due to a lack of adequate patient selection. In the last 2 decades, improvements have been made in the management of unresectable hilar CCA, and the results of LT after neoadjuvant chemoradiation have been shown to be promising. This has prompted a consideration of hilar CCA as an indication for LT in some centers. Furthermore, some recent research has shown promising results after LT for patients with early stages of intrahepatic CCA. A better understanding of the best tools to prognosticate the outcomes of LT for CCA is still needed. Here, we aimed to review the role of LT for the treatment of patients with perihilar and intrahepatic CCA. Also, we will discuss the most recent advances in the field and the future direction of the management of this disease in an era of transplantation oncology. Liver Transplantation 24 294-303 2018 AASLD.

Role of canonical Hedgehog signaling pathway in liver

Hedgehog (Hh) signaling pathway plays an important role in embryonic development. It becomes reactivated in many types of acute and chronic liver injuries. Hh signaling is required for liver regeneration, regulates capillarisation, controls the fates of hepatic stellate cells, promotes liver fibrosis and liver cancers. In this review, we summarize the current knowledge of the role of canonical Hh signaling pathway in adult liver. This help to understand the pathogenesis of liver diseases and find out the new effective targeted therapeutic strategies for liver diseases treatments.