MUC4 and MUC5AC are highly specific tumour-associated mucins in biliary tract cancer

RNA biosensors for detection of pancreatic cancer

Pancreatic cancer is recognized as one of the most lethal types of cancer globally, characterized by a high mortality rate and a bleak prognosis, which greatly contributes to cancer-related deaths. Forecasts suggest that by 2030, pancreatic cancer will exceed other cancer types in prevalence. The disease presents considerable difficulties owing to the lack of prominent symptoms in its early stages, restricted options for early detection, rapid progression, and unfavorable outcomes. Presently, traditional methods for diagnosing pancreatic cancer primarily rely on imaging techniques. However, these methods often entail significant costs, require considerable time, and necessitate specialized skills for both operating the equipment and interpreting the resulting images. To overcome these obstacles, the use of biosensors has been proposed as a potentially valuable tool for the early detection of pancreatic cancer. MicroRNAs (miRs), a type of small non-coding RNA molecules, have emerged as highly sensitive molecular diagnostic tools that have the potential to function as precise indicators for a range of diseases, including cancer. Biosensors have been suggested as a potential solution for tackling these challenges, offering a promising approach for the early detection of pancreatic cancer. Small non-coding RNA molecules known as MicroRNAs (miRs) have become recognized as extremely sensitive molecular diagnostic tools and can act as precise biomarkers for different diseases, such as cancer. Moreover, this manuscript presents a thorough summary of the latest innovations in nano-biosensors that have been specifically developed for the identification of non-coding RNAs related to pancreatic cancer.

Biomarkers and Management of Cholangiocarcinoma: Unveiling New Horizons for Precision Therapy

Cholangiocarcinoma (CCA) is an aggressive malignancy with limited methods for early detection, necessitating the development of reliable biomarkers for diagnosis and management. However, conventional tumor markers, such as CA19-9 and CEA, exhibit insufficient diagnostic accuracy. Recent advancements in molecular genetics have identified several actionable mutations in CCA, enabling molecularly targeted therapies that improve survival in patients harboring these genetic alterations. Cancer panels, which facilitate multiplex genetic profiling, are critical for identifying these mutations. Studies indicate that several actionable mutations are detected in CCA cases, with patients receiving mutation-guided therapies achieving markedly better outcomes. Liquid biopsies, including cell-free DNA and circulating tumor DNA, offer real-time, non-invasive approaches to monitoring tumor dynamics, heterogeneity, and treatment responses. Furthermore, numerous studies have identified non-coding RNAs in serum and bile as promising biomarkers for the diagnosis and management of CCA. On the other hand, immunotherapy, particularly immune checkpoint inhibitors, has shown efficacy in subsets of CCA patients. However, the success of these therapies is often affected by the status of the tumor immune microenvironment (TME), underscoring the need for comprehensive TME analysis to predict responses to immune checkpoint inhibitors. Despite these advances, no single biomarker currently demonstrates sufficient sensitivity or specificity for clinical application. The integration of multi-omics approaches with cutting-edge technologies holds promise for enhancing diagnostic accuracy, optimizing treatment stratification, and advancing precision medicine in CCA. These developments highlight the transformative potential of biomarkers to improve early detection, prognostic assessment, and personalized therapeutic interventions for CCA.

The Search for Risk, Diagnostic, and Prognostic Biomarkers of Cholangiocarcinoma and Their Biological and Clinicopathologic Significance

Cholangiocarcinomas (CCAs) are a heterogeneous group of malignant tumors that originate from the biliary tract. They are usually diagnosed in advanced stages, leading to a poor prognosis for affected patients. As CCA often arises as a sporadic cancer in individuals lacking specific risk factors or with heterogeneous backgrounds, and there are no defined high-risk groups, the implementation of effective surveillance programs for CCA is problematic. The identification and validation of new biomarkers useful for risk stratification, diagnosis, prognosis, and prediction of treatment response remains an unmet need for patients with CCA, even though numerous studies have been conducted lately to try to discover and validate CCA biomarkers. In this review, we overview the available information about the different types of biomarkers that have been investigated in recent years using minimally invasive biospecimens (blood, serum/plasma, bile, and urine) and their potential usefulness in diagnosis, prognosis, and risk stratification. It is widely accepted that early detection of CCA will impact patients' outcomes, by improving survival rates, quality of life, and the possibility of less invasive and/or curative treatments; however, challenges to its translation and clinical application for patients with CCA need to be resolved.

Relationship between mucin gene polymorphisms and different types of gallbladder stones

BACKGROUND

Gallstones, a common surgical condition globally, affect around 20% of patients. The development of gallstones is linked to abnormal cholesterol and bilirubin metabolism, reduced gallbladder function, insulin resistance, biliary infections, and genetic factors. In addition to these factors, research has shown that mucins play a role in gallstone formation. This study aims to explore the connection between different types of gallstones and mucin gene polymorphisms.

METHODS

For this purpose, a total of 121 patients with gallbladder stones PNS and 107 patients with healthy controls PNS were enrolled in this case-control study. One SNPs (rs4072037) of MUC1 gene、 three SNPs (rs2856111、rs41532344、rs41349846) of MUC2 gene、four SNPs (rs712005、rs2246980、rs2258447、rs2259292) of MUC4 gene、seven SNPs (rs28415193、rs56047977、rs2037089、rs2075854、rs3829224、rs2672785、rs2735709) of MUC5 gene、eight SNPs (rs10902268、rs61869016、rs573849895、rs59257210、rs7396383、rs74644072、rs7481521、rs9704308) of MUC6 gene、five SNPs (rs10229731、rs73168398、rs4729655、rs55903219、rs74974199) of MUC17 gene. We amplified SNP sites by polymerase chain reaction (PCR) using specific primer sets followed by DNA sequencing.

RESULTS

The frequencies of MUC2 rs2856111 C/T genotype (OR = 3.81, 95%CI: 1.06-13.68) was higher than the control group. MUC17 rs10229731 A/C genotype (OR = 0.33, 95%CI: 0.12-0.95), rs73168398 G/A genotype (OR = 0.26, 95%CI: 0.07-0.98), MUC6 rs10902268 G/A genotype (OR = 0.40, 95%CI: 0.17-0.95) at lower frequencies than controls. The frequencies of MUC2 rs41532344 T allele (OR = 2.55, 95%CI: 1.06-6.13), MUC4 rs712005 G allele (OR = 2.51, 95%CI: 1.20-5.22), MUC5B rs2037089 C allele (OR = 3.54, 95%CI: 1.14-11.01) and MUC5AC rs28415193 G allele (OR = 1.77, 95%CI: 1.02-3.07) were higher than the control group. MUC6 rs10902268 A allele (OR = 0.004, 95%CI: 0.00-0.27), rs61869016 C allele (OR = 0.07, 95%CI: 0.01-0.63) at lower frequencies than controls.

CONCLUSIONS

Polymorphisms in the mucin gene were linked to the formation of gallbladder stones. The MUC4 rs712005 G allele, MUC5B rs2037089 C allele, MUC2 rs41532344 T allele and MUC5AC rs28415193 G allele were found to predispose individuals to the development of the disease. MUC6 rs10902268 A allele and rs61869016 C allele were identified as protective factors. Meanwhile, MUC2 rs2856111 CT genotype was found to predispose individuals to the development of the disease. MUC17 rs10229731 AC genotype, rs73168398 GA genotype and MUC6 rs10902268 GA genotype were identified as protective factors.

Identification of a serum proteomic biomarker panel using diagnosis specific ensemble learning and symptoms for early pancreatic cancer detection

BACKGROUND

The grim (<10% 5-year) survival rates for pancreatic ductal adenocarcinoma (PDAC) are attributed to its complex intrinsic biology and most often late-stage detection. The overlap of symptoms with benign gastrointestinal conditions in early stage further complicates timely detection. The suboptimal diagnostic performance of carbohydrate antigen (CA) 19-9 and elevation in benign hyperbilirubinaemia undermine its reliability, leaving a notable absence of accurate diagnostic biomarkers. Using a selected patient cohort with benign pancreatic and biliary tract conditions we aimed to develop a data analysis protocol leading to a biomarker signature capable of distinguishing patients with non-specific yet concerning clinical presentations, from those with PDAC.

METHODS

539 patient serum samples collected under the Accelerated Diagnosis of neuro Endocrine and Pancreatic TumourS (ADEPTS) study (benign disease controls and PDACs) and the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS, healthy controls) were screened using the Olink Oncology II panel, supplemented with five in-house markers. 16 specialized base-learner classifiers were stacked to select and enhance biomarker performances and robustness in blinded samples. Each base-learner was constructed through cross-validation and recursive feature elimination in a discovery set comprising approximately two thirds of the ADEPTS and UKCTOCS samples and contrasted specific diagnosis with PDAC.

RESULTS

The signature which was developed using diagnosis-specific ensemble learning demonstrated predictive capabilities outperforming CA19-9, the only biomarker currently accepted by the FDA and the National Comprehensive Cancer Network guidelines for pancreatic cancer, and other individual biomarkers and combinations in both discovery and held-out validation sets. An AUC of 0.98 (95% CI 0.98-0.99) and sensitivity of 0.99 (95% CI 0.98-1) at 90% specificity was achieved with the ensemble method, which was significantly larger than the AUC of 0.79 (95% CI 0.66-0.91) and sensitivity 0.67 (95% CI 0.50-0.83), also at 90% specificity, for CA19-9, in the discovery set (p = 0.0016 and p = 0.00050, respectively). During ensemble signature validation in the held-out set, an AUC of 0.95 (95% CI 0.91-0.99), sensitivity 0.86 (95% CI 0.68-1), was attained compared to an AUC of 0.80 (95% CI 0.66-0.93), sensitivity 0.65 (95% CI 0.48-0.56) at 90% specificity for CA19-9 alone (p = 0.0082 and p = 0.024, respectively). When validated only on the benign disease controls and PDACs collected from ADEPTS, the diagnostic-specific signature achieved an AUC of 0.96 (95% CI 0.92-0.99), sensitivity 0.82 (95% CI 0.64-0.95) at 90% specificity, which was still significantly higher than the performance for CA19-9 taken as a single predictor, AUC of 0.79 (95% CI 0.64-0.93) and sensitivity of 0.18 (95% CI 0.03-0.69) (p = 0.013 and p = 0.0055, respectively).

CONCLUSION

Our ensemble modelling technique outperformed CA19-9, individual biomarkers and indices developed with prevailing algorithms in distinguishing patients with non-specific but concerning symptoms from those with PDAC, with implications for improving its early detection in individuals at risk.

Prognostic Impact of Mucin Expression in Curatively Resected Ampulla of Vater Cancer

Introduction: Mucins play a pivotal role in epithelial carcinogenesis; however, their role remains elusive in ampulla of Vater (AoV) cancer, regardless of histological subtype. Therefore, we investigated the clinical significance of MUC1, MUC2, MUC5AC, and MUC6 expression in AoV cancer. Methods: Using samples from 68 patients with AoV cancer, we performed immunohistochemical staining for MUC1, MUC2, MUC5AC, and MUC6 using a tissue microarray. Subsequently, we analyzed their expression patterns in relation to clinicopathological parameters and patient outcomes. Results: Of the patients, 98.5% exhibited positive expression for MUC1, while MUC2, MUC5AC, and MUC6 were expressed in 44.1%, 47.1%, and 41.2% of the patients, respectively. Correlation analyses between mucin expression and clinicopathological factors revealed no significant associations, except between MUC5AC expression and N stage. Univariate analysis demonstrated significant associations between MUC5AC expression and overall survival (OS). Multivariate analysis further confirmed that MUC5AC expression was a significant predictor of OS, along with the N stage. However, MUC5AC expression was not meaningfully associated with recurrence-free survival (RFS). The patients positive for MUC5AC expression had a considerably shorter OS than those with negative expression. Conclusions: Our study provides insights into the clinical impact of mucins on AoV cancer, regardless of the histological subtype. Although MUC1 expression is universal, MUC5AC expression is a significant prognostic indicator that correlates with lymph node metastasis and poor OS. These results emphasize the possible utility of MUC5AC as a biomarker for extensive lymph node dissection and the prognostic evaluation of patients with AoV cancer.

Recent Advancement in Diagnosis of Biliary Tract Cancer through Pathological and Molecular Classifications

Biliary tract cancers (BTCs), including intrahepatic, perihilar, and distal cholangiocarcinomas, as well as gallbladder cancer, are a diverse group of cancers that exhibit unique molecular characteristics in each of their anatomic and pathological subtypes. The pathological classification of BTCs compromises distinct growth patterns, including mass forming, periductal infiltrating, and intraductal growing types, which can be identified through gross examination. The small-duct and large-duct types of intrahepatic cholangiocarcinoma have been recently introduced into the WHO classification. The presentation of typical clinical symptoms, as well as the extensive utilization of radiological, endoscopic, and molecular diagnostic methods, is thoroughly detailed in the description. To overcome the limitations of traditional tissue acquisition methods, new diagnostic modalities are being explored. The treatment landscape is also rapidly evolving owing to the emergence of distinct subgroups with unique molecular alterations and corresponding targeted therapies. Furthermore, we emphasize the crucial aspects of diagnosing BTC in practical clinical settings.

Intrahepatic cholangiocarcinoma biomarkers: Towards early detection and personalized pharmacological treatments

Cholangiocarcinoma (CCA) is a rare malignancy originating from the biliary tree and is anatomically categorized as intrahepatic (iCCA), perihilar, and extrahepatic or distal. iCCA, the second most prevalent hepatobiliary cancer following hepatocellular carcinoma (HCC), constitutes 5-20 % of all liver malignancies, with an increasing incidence. The challenging nature of iCCA, combined with nonspecific symptoms, often leads to late diagnoses, resulting in unfavorable outcomes. The advanced phase of this neoplasm is difficult to treat with dismal results. Early diagnosis could significantly reduce mortality attributed to iCCA but remains an elusive goal. The identification of biomarkers specific to iCCA and their translation into clinical practice could facilitate diagnosis, monitor therapy response, and potentially reveal novel interventions and personalized medicine. In this review, we present the current landscape of biomarkers in each of these contexts. In addition to CA19.9, a widely recognized biomarker for iCCA, others such as A1BG, CYFRA 21-1, FAM19A5, MMP-7, RBAK, SSP411, TuM2-PK, WFA, etc., as well as circulating tumor DNA, RNA, cells, and exosomes, are under investigation. Advancing our knowledge and monitoring of biomarkers may enable us to improve diagnosis, prognostication, and apply treatments dynamically and in a more personalized manner.

Bile liquid biopsy in biliary tract cancer

Biliary tract cancers are heterogeneous in etiology, morphology and molecular characteristics thus impacting disease management. Diagnosis is complex and prognosis poor. The advent of liquid biopsy has provided a unique approach to more thoroughly understand tumor biology in general and biliary tract cancers specifically. Due to their minimally invasive nature, liquid biopsy can be used to serially monitor disease progression and allow real-time monitoring of tumor genetic profiles as well as therapeutic response. Due to the unique anatomic location of biliary tract cancer, bile provides a promising biologic fluid for this purpose. This review focuses on the composition of bile and the use of these various components, ie, cells, extracellular vesicles, nucleic acids, proteins and metabolites as potential biomarkers. Based on the disease characteristics and research status of biliary tract cancer, considerable effort should be made to increase understanding of this disease, promote research and development into early diagnosis, develop efficient diagnostic, therapeutic and prognostic markers.

Plasma Bile Acid Profiling and Modulation of Secreted Mucin 5AC in Cholangiocarcinoma

Studies investigating the potential role of circulating bile acids (BAs) as diagnostic biomarkers for cholangiocarcinoma (CCA) are sparse and existing data do not adjust for confounding variables. Furthermore, the mechanism by which BAs affect the expression of the oncogenic mucin 5AC (MUC5AC) has never been investigated. We performed a case-control study to characterise the profile of circulating BAs in patients with CCA (n = 68) and benign biliary disease (BBD, n = 48) with a validated liquid chromatography-tandem mass spectrometry technique. Odd ratios (OR) for CCA associations were calculated with multivariable logistic regression models based on a directed acyclic graph structure learning algorithm. The most promising BAs were then tested in an in vitro study to investigate their interplay in modulating MUC5AC expression. The total concentration of BAs was markedly higher in patients with CCA compared with BBD controls and accompanied by a shift in BAs profile toward a higher proportion of primary conjugated BAs (OR = 1.50, CI: 1.14 to 1.96, p = 0.003), especially taurochenodeoxycholic acid (TCDCA, OR = 42.29, CI: 3.54 to 504.63, p = 0.003) after multiple adjustments. Western blot analysis of secreted MUC5AC in human primary cholangiocytes treated with primary conjugated BAs or with TCDCA alone allowed us to identify a novel 230 kDa isoform, possibly representing a post-translationally modified MUC5AC specie.

Mucin 4 Confers Gemcitabine Resistance and an Unfavorable Prognosis in Patients with Cholangiocarcinoma via AKT Activation

Cholangiocarcinoma (CCA) exhibits aggressive biological behavior and a poor prognosis. Gemcitabine (GEM)-based chemotherapy is the first-line chemotherapy for advanced CCA but has a response rate of only 20-30%. Therefore, investigating treatments to overcome GEM resistance in advanced CCA is crucial. Among mucin (MUC) family members, MUC4 showed the greatest increase in the resistant versus parental sublines. MUC4 was upregulated in whole-cell lysates and conditioned media from gemcitabine-resistant (GR) CCA sublines. MUC4 mediated GEM resistance by activating AKT signaling in GR CCA cells. The MUC4-AKT axis induced BAX S184 phosphorylation to inhibit apoptosis and downregulated GEM transporter human equilibrative nucleoside transporter 1 (hENT1) expression. The combination of AKT inhibitors and GEM or afatinib overcame GEM resistance in CCA. In vivo, capivasertib (an AKT inhibitor) increased GEM sensitivity in GR cells. MUC4 promoted EGFR and HER2 activation to mediate GEM resistance. Finally, MUC4 expression in patient plasma correlated with MUC4 expression. Paraffin-embedded specimens from non-responders expressed significantly more MUC4 than did those from responders, and this upregulation was associated with poor progression-free survival and overall survival. In GR CCA, high MUC4 expression promotes sustained EGFR/HER2 signaling and AKT activation. The combination of AKT inhibitors with GEM or afatinib might overcome GEM resistance.

Understanding the Clinical Significance of MUC5AC in Biliary Tract Cancers

Biliary tract cancers (BTC) arise from biliary epithelium and include cholangiocarcinomas or CCA (including intrahepatic (ICC) and extrahepatic (ECC)) and gallbladder cancers (GBC). They often have poor outcomes owing to limited treatment options, advanced presentations, frequent recurrence, and poor response to available systemic therapy. Mucin 5AC (MUC5AC) is rarely expressed in normal biliary epithelium, but can be upregulated in tissues of benign biliary disease, premalignant conditions (e.g., biliary intraepithelial neoplasia), and BTCs. This mucin's numerous glycoforms can be divided into less-glycosylated immature and heavily-glycosylated mature forms. Reported MUC5AC tissue expression in BTC varies widely, with some associations based on cancer location (e.g., perihilar vs. peripheral ICC). Study methods were variable regarding cancer subtypes, expression positivity thresholds, and MUC5AC glycoforms. MUC5AC can be detected in serum of BTC patients at high concentrations. The hesitancy in developing MUC5AC into a clinically useful biomarker in BTC management is due to variable evidence on the diagnostic and prognostic value. Concrete conclusions on tissue MUC5AC are difficult, but serum detection might be relevant for diagnosis and is associated with poor prognosis. Future studies are needed to further the understanding of the potential clinical value of MUC5AC in BTC, especially regarding predictive and therapeutic value.

Research progress of bile biomarkers and their immunoregulatory role in biliary tract cancers

Biliary tract cancers (BTCs), including cholangiocarcinoma and gallbladder carcinoma, originate from the biliary epithelium and have a poor prognosis. Surgery is the only choice for cure in the early stage of disease. However, most patients are diagnosed in the advanced stage and lose the chance for surgery. Early diagnosis could significantly improve the prognosis of patients. Bile has complex components and is in direct contact with biliary tract tumors. Bile components are closely related to the occurrence and development of biliary tract tumors and may be applied as biomarkers for BTCs. Meanwhile, arising evidence has confirmed the immunoregulatory role of bile components. In this review, we aim to summarize and discuss the relationship between bile components and biliary tract cancers and their ability as biomarkers for BTCs, highlighting the role of bile components in regulating immune response, and their promising application prospects.

Expression of MUC16/CA125 Is Associated with Impaired Survival in Patients with Surgically Resected Cholangiocarcinoma

MUC16/CA125 is associated with cancer proliferation in several tumor entities. The data on MUC16 expression in cholangiocarcinoma (CCA) tissue are very limited. The aim of this study was to assess the MUC16 status and its impact on survival in CCA patients. All the patients with surgically resected CCA that were diagnosed between August 2005 and December 2021 at the University Hospital Frankfurt were retrospectively analyzed. A 7-Mucin biomarker panel was assessed by immunohistochemistry. For overall survival (OS), Kaplan−Meier curves and Cox-regression analyses were performed. Randomly selected intrahepatic cholangiocarcinoma (iCCA) were further processed for differential expression profiling. A total of 168 patients with CCA were classified as MUC16 (−) (66%, n = 111) and MUC16 (+) (34%, n = 57). Subgroup analyses revealed a median OS of 56.1 months (95% CI = 42.4−69.9 months) and 27.4 months (95% CI = 15.8−39.1 months) for MUC16 (−) and MUC16 (+), respectively (p < 0.001). In multivariate analysis, MUC16 (+) (HR = 1.6, 95% CI = 1−2.6, p = 0.032) was an independent risk factor for poor prognosis. Prominently deregulated pathways have been identified following MUC16 expression, overrepresented in cell cycle and immune system exhaustion processes. These findings suggest including MUC16 in clinical routine diagnostics as well as studying its molecular pathways to identify further mechanistic key players.

Analysis of MUC6 Genetic Variants on the Clinicopathologic Characteristics of Patients with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the leading malignancy associated with cancer-related deaths worldwide. Many studies have indicated that mucin (MUC) expression plays an important role in cancer metastasis and recurrence. MUC6 expression is observed in gastric and oncocytic phenotypes and may play an important role during cancer progression. We found the level of MUC6 is lower in HCC patients but did not affect the survival of HCC patients. Therefore, in this study, we investigated the combined effect of MUC6 polymorphisms and exposure to environmental carcinogens on the susceptibility to and clinicopathological characteristics of HCC. Three single-nucleotide polymorphisms (SNPs) of MUC6 (rs61869016, rs6597947, and rs7481521) from 1197 healthy controls and 423 HCC patients were analyzed using real-time PCR. After adjusting for other co-variants, we found that carrying a CC genotype at MUC6 rs61869016 had a lower risk of developing HCC than wildtype carriers. Moreover, patients with a smoking habit who carried the C allele of rs61869016 and T allele of rs7481521 had a higher (B or C) Child-Pugh score than other genotypes, suggesting significant functional compromise and decompensated disease. Therefore, our findings suggest that genetic variations in MUC6 may corelate to HCC and indicate progression in HCC patients.

Molecular diagnostics and biomarkers in cholangiocarcinoma

Regardless of anatomic origin, cholangiocarcinoma is generally an aggressive malignancy with a relatively high case fatality. Surgical resection with curative intent remains the best opportunity to achieve meaningful long-term survival. Most patients present, however, with advanced disease and less than 20% of patients are candidates for surgical resection. Unfortunately, even patients who undergo resection have a 5-year survival that ranges from 20 to 40%. Biomarkers are indicators of normal, pathologic, or biologic responses to an intervention and can range from a characteristic (i.e., blood pressure reading which can detect hypertension) to specific genetic mutations or proteins (i.e., carcinoembryonic antigen level). Novel biomarkers and improved molecular diagnostics represent an attractive opportunity to improve detection as well as to identify novel therapeutic targets for patients with cholangiocarcinoma. We herein review the latest advances in molecular diagnostics and biomarkers related to the early detection and treatment of patients with cholangiocarcinoma.

Diagnosis Biomarkers of Cholangiocarcinoma in Human Bile: An Evidence-Based Study

Simple Summary

A liquid biopsy has the characteristics of low trauma and easy acquisition in the diagnosis of cholangiocarcinoma. Many researchers try to find diagnostic or prognostic biomarkers of CCA through blood, urine, bile and other body fluids. Due to the close proximity of bile to the lesion and the stable nature, bile gradually comes into people’s view. The evaluation of human bile diagnostic biomarkers is not only to the benefit of screening more suitable clinical markers but also of exploring the pathological changes of the disease.

Abstract

Cholangiocarcinoma (CCA) is a multifactorial malignant tumor of the biliary tract, and the incidence of CCA is increasing in recent years. At present, the diagnosis of CCA mainly depends on imaging and invasive examination, with limited specificity and sensitivity and late detection. The early diagnosis of CCA always faces the dilemma of lacking specific diagnostic biomarkers. Non-invasive methods to assess the degree of CAA have been developed throughout the last decades. Among the many specimens looking for CCA biomarkers, bile has gotten a lot of attention lately. This paper mainly summarizes the recent developments in the current research on the diagnostic biomarkers for CCA in human bile at the levels of the gene, protein, metabolite, extracellular vesicles and volatile organic compounds.

Biomarkers of intrahepatic cholangiocarcinoma: diagnosis and response to therapy

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer behind hepatocellular carcinoma (HCC) and carries a dismal prognosis. Improved genetic analysis has paved the way for a better understanding of the distinct somatic genomic landscapes of ICC. The use of next generation sequencing has paved the way for more personalized medicine through identifying unique mutations which may prove to be therapeutic targets. The ability to identify biomarkers specific to ICC will assist in establishing a diagnosis, monitoring response to therapy, as well as assist in identifying novel therapies and personalized medicine. Herein, we discuss potential biomarkers for ICC and how these markers can assist in diagnosis, monitor response to therapy, and potentially identify novel interventions for the treatment of ICC.

Patient-derived organoids for personalized gallbladder cancer modelling and drug screening

BACKGROUND

Gallbladder carcinoma (GBC) is a relatively rare but highly aggressive cancer with late clinical detection and a poor prognosis. However, the lack of models with features consistent with human gallbladder tumours has hindered progress in pathogenic mechanisms and therapies.

METHODS

We established organoid lines derived from human GBC as well as normal gallbladder and benign gallbladder adenoma (GBA) tissues. The histopathology signatures of organoid cultures were identified by H&E staining, immunohistochemistry and immunofluorescence. The genetic and transcriptional features of organoids were analysed by whole-exome sequencing and RNA sequencing. A set of compounds targeting the most active signalling pathways in GBCs were screened for their ability to suppress GBC organoids. The antitumour effects of candidate compounds, CUDC-101 and CUDC-907, were evaluated in vitro and in vivo.

RESULTS

The established organoids were cultured stably for more than 6 months and closely recapitulated the histopathology, genetic and transcriptional features, and intratumour heterogeneity of the primary tissues at the single-cell level. Notably, expression profiling analysis of the organoids revealed a set of genes that varied across the three subtypes and thus may participate in the malignant progression of gallbladder diseases. More importantly, we found that the dual PI3K/HDAC inhibitor CUDC-907 significantly restrained the growth of various GBC organoids with minimal toxicity to normal gallbladder organoids.

CONCLUSIONS

Patient-derived organoids are potentially a useful platform to explore molecular pathogenesis of gallbladder tumours and discover personalized drugs.

Exploiting the MUC5AC Antigen for Noninvasive Identification of Pancreatic Cancer

Pancreatic cancer (PC) remains the fourth leading cause of cancer death; therefore, there is a clinically unmet need for novel therapeutics and diagnostic markers to treat this devastating disease. Physicians often rely on biopsy or CT for diagnosis, but more specific protein biomarkers are highly desired to assess the stage and severity of PC in a noninvasive manner. Serum biomarkers such as carbohydrate antigen 19-9 are of particular interest as they are commonly elevated in PC but have exhibited suboptimal performance in the clinic. MUC5AC has emerged as a useful serum biomarker that is specific for PC versus inflammation. We developed RA96, an anti-MUC5AC antibody, to gauge its utility in PC diagnosis through immunohistochemical analysis and whole-body PET in PC. Methods: In this study, extensive biochemical characterization determined MUC5AC as the antigen for RA96. We then determined the utility of RA96 for MUC5AC immunohistochemistry on clinical PC and preclinical PC. Finally, we radiolabeled RA96 with 89Zr to assess its application as a whole-body PET radiotracer for MUC5AC quantification in PC. Results: Immunohistochemical staining with RA96 distinguished chronic pancreatitis, pancreatic intraepithelial neoplasia, and varying grades of pancreatic ductal adenocarcinoma in clinical samples. 89Zr-desferrioxamine-RA96 was able to detect MUC5AC with high specificity in mice bearing capan-2 xenografts. Conclusion: Our study demonstrated that RA96 can differentiate between inflammation and PC, improving the fidelity of PC diagnosis. Our immuno-PET tracer 89Zr-desferrioxamine-RA96 shows specific detection of MUC5AC-positive tumors in vivo, highlighting the utility of MUC5AC targeting for diagnosis of PC.

Biomarkers in the diagnosis of pancreatic cancer: Are we closer to finding the golden ticket?

Pancreatic cancer (PC) is a leading cause of cancer related mortality on a global scale. The disease itself is associated with a dismal prognosis, partly due to its silent nature resulting in patients presenting with advanced disease at the time of diagnosis. To combat this, there has been an explosion in the last decade of potential candidate biomarkers in the research setting in the hope that a diagnostic biomarker may provide a glimmer of hope in what is otherwise quite a substantial clinical dilemma. Currently, serum carbohydrate antigen 19-9 is utilized in the diagnostic work-up of patients diagnosed with PC however this biomarker lacks the sensitivity and specificity associated with a gold-standard marker. In the search for a biomarker that is both sensitive and specific for the diagnosis of PC, there has been a paradigm shift towards a focus on liquid biopsy and the use of diagnostic panels which has subsequently proved to have efficacy in the diagnosis of PC. Currently, promising developments in the field of early detection on PC using diagnostic biomarkers include the detection of microRNA (miRNA) in serum and circulating tumour cells. Both these modalities, although in their infancy and yet to be widely accepted into routine clinical practice, possess merit in the early detection of PC. We reviewed over 300 biomarkers with the aim to provide an in-depth summary of the current state-of-play regarding diagnostic biomarkers in PC (serum, urinary, salivary, faecal, pancreatic juice and biliary fluid).

Dynamic change of serum CA19-9 levels in benign and malignant patients with obstructive jaundice after biliary drainage and new correction formulas

BACKGROUND

CA19-9 is one of the most widely used tumor markers in biliary-pancreatic diseases. The measured value may not factually reflect the genuine CA19-9 level secreted by tumor, which affected by biliary obstruction. There is an urgent need of developing a correction formula of CA19-9 in biliary obstructive patients to guide clinical practice and avoid making improper clinical decision.

METHODS

Clinical characteristics were collected among patients undergoing biliary drainage in our hospital between January 2014 and January 2019. By comparing the malignant and benign patients statistically, dynamic change trend of CA19-9 levels after biliary drainage was obtained. The correction formulas of CA19-9 were generated by means of linear regression.

RESULTS

121 patients, including 102 malignant and 19 benign patients, were enrolled in this study. The baseline CA19-9 level of malignant patients is much higher than that of benign patients. Total bilirubin (TB) level was found to be not related with CA19-9 value (p = 0.109). The drop proportion of the average CA19-9 level in the malignant patients (39.2%, IQR -18.4-78.6%) was much lower than that in the benign patients (75.7%, IQR 58.1-86.6%) (p = 0.014). The correction formula, CA19-9True = 0.63 × CA19-9Measured - 20.3 (R2 = 0.693, p<0.001), was generated based on the linear relation between CA19-9 after drainage and CA19-9 before drainage in malignant patients, which had similar diagnostic value with true CA19-9 value.

CONCLUSIONS

Quantitative correction formulas of CA19-9 considering the effect of biliary decompression was first proposed in this study, aiming to provide a more accurate CA19-9 level to make more accurate clinical decision and avoid making improper therapeutic schedule.

Role for Mucin-5AC in Upper and Lower Airway Pathogenesis in Mice

Mucin-5AC (MUC5AC) is a major secreted mucin in pathogenic airways. To determine its role in mucus-related airway disorders, Muc5ac-deficient (Muc5ac^-/-) and wild-type (Muc5ac^+/+) mice were compared in bleomycin-induced pulmonary fibrosis, respiratory syncytial virus (RSV) disease, and ozone toxicity. Significantly greater inflammation and fibrosis by bleomycin were developed in Muc5ac^-/- lungs compared to Muc5ac^+/+ lungs. More severe mucous cell metaplasia in fibrotic Muc5ac^-/- lungs coincided with bronchial Muc2, Muc4, and Muc5b overexpression. Airway RSV replication was higher in Muc5ac^-/- than in Muc5ac^+/+ during early infection. RSV-caused pulmonary epithelial death, bronchial smooth muscle thickening, and syncytia formation were more severe in Muc5ac^-/- compared to Muc5ac^+/+. Nasal septal damage and subepithelial mucoserous gland enrichment by RSV were greater in Muc5ac^-/- than in Muc5ac^+/+. Ozone exposure developed more severe nasal airway injury accompanying submucosal gland hyperplasia and pulmonary proliferation in Muc5ac^-/- than in Muc5ac^+/+. Ozone caused periodic acid-Schiff-positive secretion only in Muc5ac^-/- nasal airways. Lung E-cadherin level was relatively lower in Muc5ac^-/- than in Muc5ac^+/+ basally and after bleomycin, RSV, and ozone exposure. Results indicate that MUC5AC is an essential mucosal component in acute phase airway injury protection. Subepithelial gland hyperplasia and adaptive increase of other epithelial mucins may compensate airway defense in Muc5ac^-/- mice.

Establishment of a Potential Serum Biomarker Panel for the Diagnosis and Prognosis of Cholangiocarcinoma Using Decision Tree Algorithms

Potential biomarkers which include S100 calcium binding protein A9 (S100A9), mucin 5AC (MUC5AC), transforming growth factor β1 (TGF-β1), and angiopoietin-2 have previously been shown to be effective for cholangiocarcinoma (CCA) diagnosis. This study attempted to measure the sera levels of these biomarkers compared with carbohydrate antigen 19-9 (CA19-9). A total of 40 serum cases of CCA, gastrointestinal cancers (non-CCA), and healthy subjects were examined by using an enzyme-linked immunosorbent assay. The panel of biomarkers was evaluated for their accuracy in diagnosing CCA and subsequently used as inputs to construct the decision tree (DT) model as a basis for binary classification. The findings showed that serum levels of S100A9, MUC5AC, and TGF-β1 were dramatically enhanced in CCA patients. In addition, 95% sensitivity and 90% specificity for CCA differentiation from healthy cases, and 70% sensitivity and 83% specificity for CCA versus non-CCA cases was obtained by a panel incorporating all five candidate biomarkers. In CCA patients with low CA19-9 levels, S100A9 might well be a complementary marker for improved diagnostic accuracy. The high levels of TGF-β1 and angiopoietin-2 were both associated with severe tumor stages and metastasis, indicating that they could be used as a reliable prognostic biomarkers panel for CCA patients. Furthermore, the outcome of the CCA burden from the Classification and Regression Tree (CART) algorithm using serial CA19-9 and S100A9 showed high diagnostic efficiency. In conclusion, results have shown the efficacy of CCA diagnosis and prognosis of the novel CCA-biomarkers panel examined herein, which may prove be useful in clinical settings.

Prognostic value of bone marrow MUC4 expression in acute myeloid leukaemia

Background: Aberrant expression of mucin-4 (MUC4) is present in a variety of solid cancers, but the expression pattern of MUC4 and its clinical relevance in acute myeloid leukaemia (AML) is unknown. We aimed to evaluate the expression level of MUC4 and explore its prognostic value in newly diagnosed adult patients with AML. Methods: Bone marrow from 70 AML patients and 26 healthy donors was obtained. MUC4 levels were quantified by quantitative real-time PCR. Routine blood indices were measured by standard techniques. Results: Bone marrow MUC4 expression levels were significantly elevated in AML patients compared to controls at median (range) 2.77 (0.7-16.6) and 1.14 (0.5-1.99) respectively (p = 0.005). Moreover, lower MUC4 expression was strongly associated with persistent remission (p = 0.001) while higher MUC4 levels were associated with worse overall as well as disease-free survival (p = 0.011 and p = 0.006, respectively). Thus, its level may act as an indicator of disease progression. High MUC4 expression was identified as an independent prognostic predictor for both overall survival and disease-free survival. Conclusion: MUC4 over-expression is an independent predictor of a poor prognosis in AML patients.

Expression and Serum Levels of Mucin 5AC (MUC5AC) as a Biomarker for Cholangiocarcinoma: a Meta-analysis

AIM

The potential of biomarkers in detecting early cholangiocarcinoma (CCA) is facilitated by examining CCA-associated proteins from primary studies. One such protein is mucin 5AC (MUC5AC) but inconsistency of reported associations between its expression/serum levels and CCA prompts a meta-analysis to obtain more precise estimates.

METHODS

A literature search yielded 17 included articles where multiple data in some raised the number of studies to 22. We calculated pooled odds ratios (OR) and 95% confidence intervals from negative and positive readings of MUC5AC levels. Data were subgrouped by ethnicity, detection method, sample source, and cancer type.

RESULTS

Outcome in the overall analysis was non-significant but those in the subgroups were. Thus, significant associations (P < 0.001) indicating high MUC5AC levels were found in three subgroups: (i) Thai (OR 8.32) and (ii) serum (OR 4.52). Heterogeneity of these two outcomes (I² = 90-93%) was erased with outlier treatment (I² = 0%) which also modulated the pooled effects (OR 2.48-2.59). (iii) Immunoblot (OR 2.61) had low initial heterogeneity (I² = 2%). Robustness and significant tests for interaction (P_interaction = 0.01-0.02) improved MUC5AC associations with CCA in the Thai population.

CONCLUSIONS

Our pooled effect findings target the biomarker potential of MUC5AC to the Thai population.

Mucins: the Old, the New and the Promising Factors in Hepatobiliary Carcinogenesis

Mucins are large O-glycoproteins with high carbohydrate content and marked diversity in both the apoprotein and the oligosaccharide moieties. All three mucin types, trans-membrane (e.g., MUC1, MUC4, MUC16), secreted (gel-forming) (e.g., MUC2, MUC5AC, MUC6) and soluble (non-gel-forming) (e.g., MUC7, MUC8, MUC9, MUC20), are critical in maintaining cellular functions, particularly those of epithelial surfaces. Their aberrant expression and/or altered subcellular localization is a factor of tumour growth and apoptosis induced by oxidative stress and several anti-cancer agents. Abnormal expression of mucins was observed in human carcinomas that arise in various gastrointestinal organs. It was widely believed that hepatocellular carcinoma (HCC) does not produce mucins, whereas cholangiocarcinoma (CC) or combined HCC-CC may produce these glycoproteins. However, a growing number of reports shows that mucins can be produced by HCC cells that do not exhibit or are yet to undergo, morphological differentiation to biliary phenotypes. Evaluation of mucin expression levels in precursors and early lesions of CC, as well as other types of primary liver cancer (PLC), conducted in in vitro and in vivo models, allowed to discover the mechanisms of their action, as well as their participation in the most important signalling pathways of liver cystogenesis and carcinogenesis. Analysis of mucin expression in PLC has both basic research and clinical value. Mucins may act as oncogenes and tumour-promoting (e.g., MUC1, MUC13), and/or tumour-suppressing factors (e.g., MUC15). Given their role in promoting PLC progression, both classic (MUC1, MUC2, MUC4, MUC5AC, MUC6) and currently tested mucins (e.g., MUC13, MUC15, MUC16) have been proposed to be important diagnostic and prognostic markers. The purpose of this review was to summarize and update the role of classic and currently tested mucins in pathogenesis of PLC, with explaining the mechanisms of their action in HCC carcinogenesis. It also focuses on determination of the diagnostic and prognostic role of these glycoproteins in PLC, especially focusing on HCC, CC and other hepatic tumours with- and without biliary differentiation.

Meta-analysis of the diagnostic value of Wisteria floribunda agglutinin-sialylated mucin1 and the prognostic role of mucin1 in human cholangiocarcinoma

OBJECTIVE

Serum carbohydrate antigen 19-9 (CA19-9) is a widely used tumour marker for cholangiocarcinoma (CCA). However, it is not a necessarily good CCA marker in terms of diagnostic accuracy. The purpose of this study is to evaluate the diagnostic value of Wisteria floribundaagglutinin-sialylated Mucin1 (WFA-MUC1) and the prognostic role of Mucin1 (MUC1) in human CCA.

DESIGN

Meta-analysis.

DATA SOURCES

Studies published in PubMed, Web of Science, The Cochrane Library and the China National Knowledge Infrastructure up to 11 October 2017.

ELIGIBILITY CRITERIA

We included reports assessing the diagnostic capacity of WFA-MUC1 and the prognostic role of MUC1 in CCA. The receiver operating characteristic curve (ROC) of WFA-MUC1 and/or CA19-9 was described, and the HRs including 95% CI and the corresponding p value for MUC1 can be extracted.

DATA EXTRACTION AND SYNTHESIS

Two independent researchers extracted data and assessed risk of bias. The diagnostic sensitivity and specificity data of WFA-MUC1 were extracted and analysed as bivariate data. Pooled HRs and its 95% CI for MUC1 were calculated with a random-effects meta-analysis model on overall survival of resectable CCA.

RESULTS

Sixteen reports were included in this study. The pooled sensitivity and specificity of WFA-MUC1 were 0.76 (95% CI 0.71 to 0.81) and 0.72 (95% CI 0.59 to 0.83) in serum, 0.85 (95% CI 0.81 to 0.89) and 0.72 (95% CI 0.64 to 0.80) in bile and 0.72 (95% CI 0.50 to 0.87) and 0.85 (95% CI 0.70 to 0.93) in tissue, respectively. The summary ROC (SROC) were 0.77 (95% CI 0.73 to 0.81) in serum, 0.88 (95% CI 0.85 to 0.90) in bile and 0.86 (95% CI 0.83 to 0.89) in tissue, respectively. Furthermore, the pooled sensitivity and specificity and the SROC of CA19-9 in serum were 0.67 (95% CI 0.61 to 0.72), 0.86 (95% CI 0.75 to 0.93) and 0.75 (95% CI 0.71 to 0.79), respectively. The pooled HRs for MUC1 was 2.20 (95% CI 1.57 to 3.01) in CCA and 4.17 (95% CI 1.71 to 10.17) in mass-forming intrahepatic CCA.

CONCLUSIONS

Compared with CA19-9, WFA-MUC1 was shown to possess stronger diagnostic capability. MUC1 could serve as a prognosis factor for poor outcomes of CCA, particularly, mass-forming intrahepatic CCA.

Current and future roles of mucins in cholangiocarcinoma-recent evidences for a possible interplay with bile acids

Cholangiocarcinoma (CCA) is rare but highly malignant tumour. The diagnosis is difficult due to its silent clinical character and the inefficiency of currently available diagnostic markers. An enhanced understanding of the molecular pathways involved in CCA carcinogenesis would herald targeted, individualized therapies, as well as new early diagnostic tool with improvement of patient survival. Recently, two mucin proteins, MUC4 and MUC5 have gained interest for their involvement in tumour growth and progression and possible use as diagnostic and prognostic cancer biomarkers. Moreover, a number of studies have demonstrated an association between biliary or serum bile acids (BAs) and some forms of cancers including CCA. More importantly, BAs have been shown to participate in tumour progression by inducing alterations in the expression of oncogenic mucins. This review summarizes the most important findings regarding the possible use of mucin glycoproteins and BAs in the diagnosis and prognostication of CCA and discuss evidences suggesting a role of BAs in regulating the expression of transmembrane and secreted mucins.

Identification of a serum biomarker panel for the differential diagnosis of cholangiocarcinoma and primary sclerosing cholangitis

The non-invasive differentiation of malignant and benign biliary disease is a clinical challenge. Carbohydrate antigen 19-9 (CA19-9), leucine-rich α2-glycoprotein (LRG1), interleukin 6 (IL6), pyruvate kinase M2 (PKM2), cytokeratin 19 fragment (CYFRA21.1) and mucin 5AC (MUC5AC) have reported utility for differentiating cholangiocarcinoma (CCA) from benign biliary disease. Herein, serum levels of these markers were tested in 66 cases of CCA and 62 cases of primary sclerosing cholangitis (PSC) and compared with markers of liver function and inflammation. Markers panels were assessed for their ability to discriminate malignant and benign disease. Several of the markers were also assessed in pre-diagnosis biliary tract cancer (BTC) samples with performances evaluated at different times prior to diagnosis. We show that LRG1 and IL6 were unable to accurately distinguish CCA from PSC, whereas CA19-9, PKM2, CYFRA21.1 and MUC5AC were significantly elevated in malignancy. Area under the receiver operating characteristic curves for these individual markers ranged from 0.73–0.84, with the best single marker (PKM2) providing 61% sensitivity at 90% specificity. A panel combining PKM2, CYFRA21.1 and MUC5AC gave 76% sensitivity at 90% specificity, which increased to 82% sensitivity by adding gamma-glutamyltransferase (GGT). In the pre-diagnosis setting, LRG1, IL6 and PKM2 were poor predictors of BTC, whilst CA19-9 and C-reactive protein were elevated up to 2 years before diagnosis. In conclusion, LRG1, IL6 and PKM2 were not useful for early detection of BTC, whilst a model combining PKM2, CYFRA21.1, MUC5AC and GGT was beneficial in differentiating malignant from benign biliary disease, warranting validation in a prospective trial.

Cell membrane-anchored MUC4 promotes tumorigenicity in epithelial carcinomas

The cell surface membrane-bound mucin protein MUC4 promotes tumorigenicity, aggressive behavior, and poor outcomes in various types of epithelial carcinomas, including pancreatic, breast, colon, ovarian, and prostate cancer. This review summarizes the theories and findings regarding MUC4 function, and its role in epithelial carcinogenesis. Based on these insights, we developed an outline of the processes and mechanisms by which MUC4 critically supports the propagation and survival of cancer cells in various epithelial organs. MUC4 may therefore be a useful prognostic and diagnostic tool that improves our ability to eradicate various forms of cancer.

Potential prognostic biomarkers in pancreatic juice of resectable pancreatic ductal adenocarcinoma

Despite potentially curative surgery pancreatic cancer has a dismal prognosis. Serum cancer antigen 19-9 (CA 19-9) correlates with tumor burden, resectability and survival in patients with pancreatic ductal adenocarcinoma. Identification of novel biomarkers may facilitate early diagnosis of pancreatic cancer and improve survival. Pancreatic juice is a rich source of cancer-specific proteins rendering it a promising tool for identifying biomarkers. Recent proteomic and microRNA expression analyses have identified several biomarkers of potential diagnostic and prognostic value. Tumor markers CA 19-9 and carcinoembryonic antigen (CEA) are widely used in the characterization of premalignant and malignant lesions of the pancreas. Elevated level of CEA in bile is a marker for malignancy and a predictor of hepatic recurrence. The potential value of CA 19-9, CEA and lactate dehydrogenase as prognostic biomarkers in pancreatic juice and bile is unknown. Specimens of pancreatic juice and bile can be readily collected during surgical resection of the tumor. Profiling of pancreatic juice and bile to identify novel prognostic biomarkers may improve selection of patients for adjuvant therapy with a favorable impact on overall survival in patients diagnosed with pancreatic cancer.

Intrahepatic cholangiocarcinoma: Molecular markers for diagnosis and prognosis

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver tumor with increasing incidence worldwide. The outcome of patients with iCCA is dismal owing to tumor's aggressiveness, late diagnosis and lack of effective treatment options. Detection of the tumor at early stages may make surgical resection, as only potential curative treatment, more feasible. Unfortunately, despite recent developments in imaging modalities and laboratory tests, the diagnosis of iCCA remains challenging and patients often present in advanced stages when surgery cannot be offered. Moreover, accurate assessment of disease burden is critical to optimize management strategy, including the use of adjuvant therapies and clinical trials. Identifying iCCA specific diagnostic and prognostic biomarkers has been a focus of interest among many investigators with a progressive increase in data on iCCA related to advances in "omics" technologies. We herein summarize iCCA biomarkers and define the molecular mechanisms underlying iCCA carcinogenesis, as well as highlight potential diagnostic and prognostic application of molecular biomarkers.

Interleukin-13 stimulates MUC5AC expression via a STAT6-TMEM16A-ERK1/2 pathway in human airway epithelial cells

Transmembrane protein 16A (TMEM16A), a channel underlying the calcium-activated chloride channel (CaCC) currents, has been shown to be a key regulator of mucus overproduction in airway epithelial cells. However, the precise molecular mechanism involved in the TMEM16A-mediated mucus secretion remains unclear. In the present study, we inquired into a novel signaling mechanism for TMEM16A driving mucin 5AC (MUC5AC) production in human airway epithelial cells. Following treatment for 24-48h with type 13 interleukin (IL-13), an upregulation of TMEM16A expression in both mRNA and protein levels was observed in human bronchial epithelial cell line (HBE16), while signal transducer and activator of transcription 6 (STAT6) inhibition could decrease this elevated expression, suggesting that the regulation of TMEM16A expression by IL-13 was via a STAT6-based transcriptional mechanism. Further investigation of the HBE16 cells revealed that TMEM16A knockdown or specific chloride channel inhibitor T16Ainh-A01 could suppress the CaCC currents and consequently reduce the extracellular regulated kinase (ERK1/2) phosphorylation, accompanying a dramatical decrease in MUC5AC expression. Moreover, pretreated with PD98059, an inhibitor of ERK1/2, the HB16 cells showed a remarkable diminution in TMEM16A-mediated MUC5AC expression. Altogether, STAT6-TMEM16A-ERK1/2 signal pathway and TMEM16A channel activity are required for the IL-13-induced TMEM16A mediated mucus production.

Prognostic Role of Mucin Antigen MUC4 for Cholangiocarcinoma: A Meta-Analysis

Background and Objective

Surgery carries the best hope for cure in the treatment of cholangiocarcinoma (CC), whereas surgical outcome is not fully satisfactory. Bio-molecular markers have been used to improve tumor staging and prognosis prediction. Mucin antigen MUC4 (MUC4) has been implicated as a marker for poor survival in various tumors. However, prognostic significance of MUC4 for patients with CC remains undefined. The aim of the present meta-analysis was to investigate the association between MUC4 expression and overall survival (OS) of patients with resected CC.

Methods

The meta-analysis was conducted in adherence to the MOOSE guidelines. PubMed, Embase databases, Cochrane Library and the Chinese SinoMed were systematically searched to identify eligible studies from the initiation of the databases to April, 2016. OSs were pooled by using hazard ratio (HR) with corresponding 95% confidence interval (CI). Random effect models were utilized because of the between-study heterogeneities.

Results

Five studies reporting on 249 patients were analyzed: 94 (37.75%) were in positive or high expression group and 155 (62.25%) in negative or low expression group. The pooled HR for positive or high expression group was found to be 3.04 (95% CI 2.25–4.12) when compared with negative or low expression group with slight between-study heterogeneities (I² 3.10%, P = 0.39). The result indicated that a positive or high expression level of MUC4 was significantly related to poor survival in patients with resected CC. A commensurate result was identified by sensitivity analysis. The main limitations of the present meta-analysis were the rather small size of the studies included and relatively narrow geographical distribution of population.

Conclusion

The result of this meta-analysis indicated that a positive or high expression level of MUC4 was significantly related to poor survival in patients with resected CC.

The diagnostic performance of serum MUC5AC for cholangiocarcinoma: A systematic review and meta-analysis

Specific diagnostic biomarker for cholangiocarcinoma (CCA) has been lacking. This systematic review and meta-analysis was performed aiming to investigate serum MUC5AC's diagnostic performance on CCA.Studies investigating serum MUC5AC's diagnostic value on CCA were retrieved from Pubmed, Embase, and Cochrane Library. The methodology quality of included studies was assessed according to QUADAS-2. Diagnostic 2 × 2 table was extracted from each eligible study, Meta-disc 1.4 was used for statistical analysis, data synthesis was done using a random-effects model. Subgroup analyses were conducted according to region and array method.Six eligible studies were identified, a total of 1213 patients were involved in the meta-analysis. The AUC on SROC was 0.9138, and the Q* was 8463. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio (DOR) were 0.69 (95% CI: 0.65-0.73), 0.93 (95% CI: 0.91-0.95), 8.99 (95% CI: 5.65-14.30), 0.33 (95% CI: 0.24-0.46), and 33.98 (95% CI: 20.12-57.40), respectively. Targeting MUC5AC's epitope has a higher pooled sensitivity than targeting MUC5AC protein (0.77 vs 0.63). There was substantial cross-study heterogeneity.Serum MUC5AC might be potentially used as a surrogate marker in the diagnosis of CCA. However, the appropriate array method and the optimum cut-off value are yet to be decided.

Potential diagnostic and prognostic biomarkers for cholangiocarcinoma in serum and bile

Cholangiocarcinoma (CCA) is a devastating malignancy that is difficult to treat because of its insensitivity to conventional therapies and the inability to detect early tumor formation. Novel molecular techniques have enabled the use of serum and bile markers for CCA diagnosis and prognosis. Herein, we summarize the principal characteristics of serum and bile markers of CCA. Biomarkers such as interleukin-6, matrix metalloproteinases, serotonin (5-hydroxytryptamine) and bile acids have shown promise for improving CCA diagnosis. Several markers such as CYFRA 21-1, MK-1 and C-reactive protein were recently shown to be effective for CCA prognosis.

Hyper Expression of Mucin 5ac Indicates Poor Cancer Prognoses: A Meta-Analysis

The aim of the study was to explore the association between mucin 5ac expression and cancer prognosis. A systematically comprehensive search was performed through PubMed, the Web of Science, and the China National Knowledge Infrastructure (CNKI). The prognostic value of mucin 5ac expression in cancer patients was evaluated. The overexpression of mucin 5ac was found to be significantly associated with a poor prognosis in cancer patients (pooled HR: 1.53, 95%CI: 1.158-2.028, P = 0.003). This association was also detected in a biliary subgroup (pooled HR: 1.83, 95%CI: 1.269-2.639, P = 0.001) and a gastrointestinal subgroup (pooled HR: 1.44, 95%CI: 1.069-1.949 P = 0.017). In the geography subgroup analysis, a statistical association was found in the Asian subgroup (pooled HR: 1.69, 95%CI: 1.200-2.384, P = 0.003). In the clinical characteristics analysis, a statistical association was found between the hyper expression of mucin 5ac and lymphatic metastasis. We indicated that mucin 5ac is a promising prognostic predictor for cancer, especially for biliary and gastrointestinal cancer, and is more suitable for predicting cancer prognoses in Asians.

TMEM16A mediates the hypersecretion of mucus induced by Interleukin-13

Previous studies showed that the Ca(2+)-activated Cl(-) channel (CaCC) was involved in the pathogenesis of mucus hypersecretion induced by Interleukin-13 (IL-13). However, the mechanisms underlying the process were unknown. Recently, transmembrane protein 16A (TMEM16A) was identified as the channel underlying the CaCC current. The aim of the current study was to investigate whether the TMEM16A channel is part of the mechanism underlying IL-13-induced mucus hypersecretion. We observed that both TMEM16A mRNA and protein expression were significantly up-regulated after treatment with IL-13 in human bronchial epithelial 16 (HBE 16) cells, which correlated with an increase in mucus production. Additionally, mucus hypersecretion in rat airways was induced by intratracheal instillation of IL-13 and similar increases were observed in the expression of TMEM16A mRNA and protein in the bronchial epithelium. Niflumic acid (NA), a selective antagonist of CaCC, markedly blocked IL-13-induced mucin (MUC) 5AC mRNA and protein production in vivo and in vitro. Further investigation with HBE16 cells revealed that TMEM16A overexpression clearly promoted mucus production, IκBα phosphorylation, and p65 accumulation in the nucleus. The loss of TMEM16A resulted in inhibition of mucus production, and the TMEM16A-mediated production of MUC5AC was significantly blocked by a nuclear factor-kappa B (NF-κB) inhibitor. Therefore, the TMEM16A channel acts upstream of NF-κB in the regulation of mucus production. This is the first demonstration that the TMEM16A-NF-κB pathway is positively involved in IL-13-induced mucus production, which provides novel insight into the molecular mechanism of mucin overproduction.

Histological and Molecular Subclassification of Pancreatic and Nonpancreatic Periampullary Cancers: Implications for (Neo) Adjuvant Systemic Treatment

The benefit of adjuvant chemotherapy for resected pancreatic ductal adenocarcinoma (PDAC) has been confirmed in randomized controlled trials. For nonpancreatic periampullary cancers (NPPC) originating from the distal bile duct, duodenum, ampulla, or papilla of Vater, the role of adjuvant therapy remains largely unclear. This review describes methods for distinguishing PDAC from NPPC by means of readily available and recently developed molecular diagnostic methods. The difficulties of reliably determining the exact origin of these cancers pathologically also is discussed. The review also considers the possibility of unintentional inclusion of NPPC in the most important adjuvant trials on PDAC and the subsequent implications for interpretation of the results. The authors conclude that correct determination of the origin of periampullary cancers is essential for clinical management and should therefore be systematically incorporated into clinical practice and future studies.

Bile proteome in health and disease

The study of bile proteins could improve the understanding of physiological processes involved in the regulation of the hepato-biliary system. Researchers have tried for years to investigate the bile proteome but, until recently, only a few tens of proteins were known. The advent of proteomics, availing of large-scale analytical devices paired with potent bioinformatic resources, lately allowed the identification of thousands of proteins in bile. Nevertheless, the knowledge of their role in the hepato-biliary system still represents almost a "blank page in the book of physiology." In this review, we first guide the reader through the historical phases of the analysis of bile protein content, emphasizing the recent progresses achieved through the use of proteomic techniques. Thereafter, we deeply explore the involvement of bile proteins in health and disease, with a particular focus on the discovery of biomarkers for biliary tract malignancies.

Assessment of bile and serum mucin5AC in cholangiocarcinoma: diagnostic performance and biologic significance

BACKGROUND

Recent studies have showed the efficacy of mucin5AC (MUC5AC) as a diagnostic and prognostic serum biomarker in biliary tract tumors. The aim of the present investigation was to improve the current knowledge on the biologic relevance of MUC5AC in malignant and benign biliary disorders by comparing its diagnostic performance in both bile and serum samples of patients with cholangiocarcinoma (CCA) or benign biliary disorders.

METHODS

A quantitative determination of MUC5AC by enzyme-linked immunosorbent assay was performed in bile and serum specimens from 26 patients with extrahepatic CCA and 20 subjects with benign biliary disorders (10 with biliary stones and 10 with cholangitis). Verification analysis was made by immunoblot.

RESULTS

MUC5AC of serum and biliary origin contributed to different extent to total levels of MUC5AC in the different groups of patients. In particular, the transition toward a greater degree of injury of bile duct epithelium was accompanied by a greater amount of MUC5AC in serum than in bile. The diagnostic performance of MUC5AC expressed as serum/bile ratio showed excellent diagnostic performance for differentiating CCA from cholangitis (area under the curve [AUC], 0.94; 95% CI, 0.86-1.00; P < .0001), CCA from biliary stones (AUC, 0.99; 95% CI, 0.98-1.00; P < .0001), as well as cholangitis from biliary stones (AUC, 0.93; 95% CI, 0.82-1.00; P = .001).

CONCLUSION

These findings provide new insight into the biologic importance of MUC5AC in biliary disorders and suggest that combined assessment of MUC5AC in bile and serum with expression of data in terms of serum to bile ratio may improve the diagnostic performance of MUC5AC quantification in serum alone.

Serum tumor markers in bile duct cancer--a review

CONTEXT

Bile duct cancer (BDC) is a disease with a very grave prognosis, often diagnosed too late.

OBJECTIVE

The aim of this review is to evaluate available literature on tumor markers in serum from patients with BDC.

METHODS

Using the search words "serum markers", "bile duct cancer", "cholangiocarcinoma", "biomarker" and "tumor marker", a search was carried out.

RESULTS

Seventy-five studies were included in the review.

CONCLUSION

CA19-9 is by far the most studied and most promising diagnostic and/or prognostic marker in BDC. But also the different mucins are interesting as new markers of BDC in serum.

Sensitivity of alternative testing for pancreaticobiliary cancer: a 10-y review of the literature

BACKGROUND

Biliary strictures present a diagnostic challenge to differentiate benign disease from hepatopancreaticobiliary (HPB) malignancies. Endoscopic retrograde cholangiopancreatography cytology is commonly performed in these patients; however, its sensitivity for diagnosis of HPB malignancy is poor (41.6%). Many adjunctive tests have been investigated to improve the sensitivity of HPB biopsies. To determine the best tests available, however, we reviewed the literature and performed a comparative analysis of all recently investigated tests and their sensitivities.

METHODS

A PubMed search identified articles published between 2003 and 2014, describing alternate methods for diagnosing HPB malignancies, reported sensitivity, final pathology, and had data available online. Meta-analysis was conducted for tests with multiple articles. Tests with the highest sensitivity and specificities were reported.

RESULTS

A total of 77 studies were identified. Meta-analysis was performed on the sensitivity of EUS-FNA (74.2%), fluorescence in situ hybridization (54.2%), immunostain of insulin-like growth factor 2 mRNA-binding Protein 3 (IMP3; 80.4%), IMP3 + cytology (86.4%), K homology domain containing protein overexpressed in cancer (KOC; 85.9%), S100P (77.8%), serum CA19-9 (69.3%), and K-ras mutations (47.0%) to detect malignancy. Ultimately, 12 tests were identified with superior sensitivity (85.3%-100%) and specificities (81.6%-100%) including stricture scrapping, brush sectioning, IMP3 stain + cytology, IMP3+S100A4, bile carcinoembryonic cell adhesion molecule 6 protein (±CA19-9), bile micro RNA (miRNA)-135b, serum miRNA-RNU2-1f, serum miRNA-21 (+CA19-9), peripheral blood mononuclear cells miRNA-27a-3p (+CA19-9), serum miRNA-16 + miRNA-196a (+CA19-9), peripheral blood mononuclear cells mRNAs h-TERT + CK20 + CEA + C-MET.

CONCLUSIONS

We recommend immunostaining with a panel of IMP3+KOC + S100A4 + cytology to achieve maximum sensitivity and specificity from HPB biopsies. One biliary protein (carcinoembryonic cell adhesion molecule 6) and several RNAs (bile and blood) offer exceptional sensitivity and specificity and should be tested prospectively in larger populations. Overall, this review identifies several tests to improve the sensitivity of diagnostic algorithms to identify HPB malignancies.

A novel serum marker for biliary tract cancer: diagnostic and prognostic values of quantitative evaluation of serum mucin 5AC (MUC5AC)

BACKGROUND AND AIMS

Mucin 5AC (MUC5AC) is a glycoprotein found in different epithelial cancers, including biliary tract cancer (BTC). The aims of this study were to investigate the role of MUC5AC as serum marker for BTC and its prognostic value after operation with curative intent.

PATIENTS AND METHOD

From January 2007 to July 2012, a quantitative assessment of serum MUC5AC was performed with enzyme-linked immunoassay in a total of 88 subjects. Clinical and biochemical data (including CEA and Ca 19-9) of 49 patients with BTC were compared with a control population that included 23 patients with benign biliary disease (BBD) and 16 healthy control subjects (HCS).

RESULTS

Serum MUC5AC was greater in BTC patients (mean 17.93 ± 10.39 ng/mL) compared with BBD (mean 5.95 ± 5.39 ng/mL; P < .01) and HCS (mean 2.74 ± 1.35 ng/mL) (P < .01). Multivariate analysis showed that MUC5AC was related with the presence of BTC compared with Ca 19-9 and CEA: P < .01, P = .080, and P = .463, respectively. In the BTC group, serum MUC5AC ≥ 14 ng/mL was associated with lymph-node metastasis (P = .050) and American Joint Committee on Cancer and International Union for Cancer Control stage IVb disease (P = .047). Moreover, in patients who underwent operation with curative intent, serum MUC5AC ≥ 14 ng/mL was related to a worse prognosis compared with patients with lesser levels, with 3-year survival rates of 21.5% and 59.3%, respectively (P = .039).

CONCLUSION

MUC5AC could be proposed as new serum marker for BTC. Moreover, the quantitative assessment of serum MUC5AC could be related to tumor stage and long-term survival in patients with BTC undergoing operation with curative intent.

Novel diagnostic and prognostic biomarkers in biliary tract cancer

INTRODUCTION

The worldwide incidence of biliary tract carcinoma (BTC, tumours of the bile ducts and gall-bladder) continues to rise, with the only potentially curative treatment remaining surgical resection or transplantation, possible in only a minority of patients. Late presentation and a paucity of effective treatments mandate the development of techniques for early lesion detection.

AREAS COVERED

This article reviews currently available biomarkers for the diagnosis and prognosis of BTC, as well as recently published studies describing novel serum, bile and urinary biomarkers.

EXPERT OPINION

The incorporation of novel analysis techniques, such as digital image analysis and fluorescence in situ hybridization, into existing management algorithms enhances the accuracy of brush cytology taken at the time of therapeutic endoscopy. However, a key goal is the discovery of reliable non-invasive biomarkers with high sensitivity and specificity. Recent advances in gene sequencing and expression, clonal evolution and tumour heterogeneity in other cancers should advance understanding of BTC tumour biology and facilitate biomarker discovery.

Prognostic significance of muc4 expression in gallbladder carcinoma

Background

Mucins are high molecular glycoproteins and play protective and lubricating roles in various epithelial tissues. Deregulated expression of mucins is involved in carcinogenesis and tumor invasion. MUC4 expression has been identified as a poor prognostic factor in pancreatobiliary carcinomas. To date, the relation between MUC4 expression and prognosis in gallbladder carcinoma remains to be determined. Authors examined MUC4 expression in gallbladder carcinoma and investigated its impact on prognosis.

Methods

The expression profiles of MUC4, MUC1, MUC2 mucins in gallbladder carcinoma tissues from 63 patients were investigated using immunohistochemical staining.

Results

For gallbladder carcinoma, positive staining of MUC4, MUC1, and MUC2 was 55.6%, 81.0%, 28.6%, respectively. There was a significant correlation between the expression of MUC4 and the expression of MUC1 or MUC2 (p = 0.004, p = 0.009, respectively). Univariate analysis showed that MUC4 expression (p = 0.047), differentiation (p < 0.05), T-stage (p < 0.05) and lymph node metastasis (p < 0.001) were significantly associated with poor survival. Expression of MUC1 and MUC2 was not correlated to survival. The backward stepwise multivariate analysis showed that MUC4 expression (p = 0.039) and lymph node metastasis (p = 0.001) were significant independent risk factors. In combined assessment of MUC4 and MUC2 expression, MUC4 positive and MUC2 negative group showed a significantly worse outcome than MUC4 negative groups(MUC4-/MUC2+ and MUC4-/MUC2-) and MUC4/MUC2 co-expression group(MUC4+/MUC2+) (p < 0.05).

Conclusions

MUC4 expression in gallbladder carcinoma is an independent poor prognostic factor. Therefore, MUC4 expression may be a useful marker to predict the outcome of patients with surgically resected gallbladder carcinoma. MUC2 expression may have prognostic value when combined with MUC4 expression.