New biomarkers and targets in pancreatic cancer and their application to treatment

Postbiotic butyrate: role and its effects for being a potential drug and biomarker to pancreatic cancer

Postbiotics are produced by microbes and have recently gained importance in the field of oncology due to their beneficial effects to the host, effectiveness against cancer cells, and their ability to suppress inflammation. In particular, butyrate dominates over all other postbiotics both in quantity and anticancer properties. Pancreatic cancer (PC), being one of the most malignant and lethal cancers, reported a decreased 5-year survival rate in less than 10% of the patients. PC causes an increased mortality rate due to its inability to be detected at an early stage but still a promising strategy for its diagnosis has not been achieved yet. It is necessary to diagnose Pancreatic cancer before the metastatic progression stage. The available blood biomarkers lack accurate and proficient diagnostic results. Postbiotic butyrate is produced by gut microbiota such as Rhuminococcus and Faecalibacterium it is involved in cell signalling pathways, autophagy, and cell cycle regulation, and reduction in butyrate concentration is associated with the occurrence of pancreatic cancer. The postbiotic butyrate is a potential biomarker that could detect PC at an early stage, before the metastatic progression stage. Thus, this review focused on the gut microbiota butyrate's role in pancreatic cancer and the immuno-suppressive environment, its effects on histone deacetylase and other immune cells, microbes in major butyrate synthesis pathways, current biomarkers in use for Pancreatic Cancer.

A Machine Learning Method for a Blood Diagnostic Model of Pancreatic Cancer Based on microRNA Signatures

This study aimed to construct a blood diagnostic model for pancreatic cancer (PC) using miRNA signatures by a combination of machine learning and biological experimental verification. Gene expression profiles of patients with PC and transcriptome normalization data were obtained from the Gene Expression Omnibus (GEO) database. Using random forest algorithm, lasso regression algorithm, and multivariate cox regression analyses, the classifier of differentially expressed miRNAs was identified based on algorithms and functional properties. Next, the ROC curve analysis was used to evaluate the predictive performance of the diagnostic model. Finally, we analyzed the expression of two specific miRNAs in Capan-1, PANC-1, and MIA PaCa-2 pancreatic cells using qRT-PCR. Integrated microarray analysis revealed that 33 common miRNAs exhibited significant differences in expression profiles between tumor and normal groups (P value < 0.05 and |logFC| > 0.3). Pathway analysis showed that differentially expressed miRNAs were related to P00059 p53 pathway, hsa04062 chemokine signaling pathway, and cancer-related pathways including PC. In ENCORI database, the hsa-miR-4486 and hsa-miR-6075 were identified by random forest algorithm and lasso regression algorithm and introduced as major miRNA markers in PC diagnosis. Further, the receiver operating characteristic curve analysis achieved the area under curve score > 80%, showing good sensitivity and specificity of the two-miRNA signature model in PC diagnosis. Additionally, hsa-miR-4486 and hsa-miR-6075 genes expressions in three pancreatic cells were all up-regulated by qRT-PCR. In summary, these findings suggest that the two miRNAs, hsa-miR-4486 and hsa-miR-6075, could serve as valuable prognostic markers for PC.

miR-18a and miR-106a Signatures in Plasma Small EVs Are Promising Biomarkers for Early Detection of Pancreatic Ductal Adenocarcinoma

Pancreatic cancer is the third leading cause of cancer-related death in the United States. Pancreatic ductal adenocarcinoma (PDAC) is the major form of pancreatic cancer with the worst outcomes. Early detection is key to improving the overall survival rate of PDAC patients. Recent studies have demonstrated that microRNA (miRNA) signatures in plasma small extracellular vesicles (EVs) are potential biomarkers for the early detection of PDAC. However, published results are inconsistent due to the heterogeneity of plasma small EVs and the methods used for small EV isolation. We have recently refined the process of plasma small EV isolation using double filtration and ultracentrifugation. In the present study, we applied this protocol and analyzed plasma small EV miRNA signatures by small RNA sequencing and quantitative RT-PCR in a pilot cohort, consisting of patients with early-stage PDAC, and age- and gender-matched healthy subjects (n = 20). We found, via small RNA sequencing, that there are several miRNAs enriched in plasma small EVs of PDAC patients, and the levels of miR-18a and miR-106a were confirmed by quantitative RT-PCR to be significantly elevated in patients with early-stage PDAC compared with age- and gender-matched healthy subjects. Furthermore, using an immunoaffinity-based plasma small EV isolation approach, we confirmed that the levels of miR-18a and miR-106a in plasma small EVs were significantly higher in PDAC patients versus the healthy subjects. We thus conclude that the levels of miR-18a and miR-106a in plasma small EVs are promising biomarkers for the early detection of PDAC.

Can combined use of tumor markers in pancreatic cancer be a solution to short- and long-term consequences?: A retrospective study

As in other types of cancer, tumor markers are used in pancreatic ductal adenocarcinoma (PDAC) for disease follow-up, especially after surgery. There has been shown to be a significant correlation between the tumor marker levels and poor prognosis in locally or systemic advanced stage PDAC patients. However, there is no significant correlation between prognosis and marker levels in patients with early stage PDAC patients. This study aimed to examine the effect of the carbohydrate antigen 19-9 (Ca19-9)/carcinoembryogenic antigen (CEA) ratio in ductal adenocarcinoma of the pancreatic head on disease prognosis and mean survival. This retrospective study was conducted with 129 pancreatic head adenocarcinoma patients who were treated with whipple procedure at the Ankara University Surgical Oncology Clinic between 2010 and 2020. All patients' demographics, stage of the disease, CEA, CA 19-9 levels, and CEA/Ca 19-9 ratio were enrolled and compared statistically. A new cutoff value was calculated for the Ca19-9/CEA ratio. A Ca19-9/CEA ratio >29.77 showed 69.9% sensitivity and 70.9% specificity for the probability of the T3 and T4 stages. The cutoff value for the Ca19-9/CEA ratio was 27.18. This cutoff value had a sensitivity of 79.4% and a specificity of 80.3% for lymph node metastasis. Patients with a Ca19-9/CEA ratio below the cutoff value of 28.475 had a mean survival of 93.161 months and those with a value higher than the cutoff value had a mean survival of 28.541 months (P < .001). A simple combination of tumor markers was determined to have higher accuracy rates in predicting tumor prognosis and in determining mean survival, which are particularly needed in early stage cancers.

ENO1 promotes immunosuppression and tumor growth in pancreatic cancer

BACKGROUND

Pancreatic adenocarcinoma (PAAD) is a highly aggressive and malignant cancer type with the highest mortality rate of all major cancers. However, the molecular and tumor immune escape mechanism underlying pancreatic cancer remains largely unclear. α-enolase (ENO1) is a glycolytic enzyme reported to overexpress in a variety of cancer types. This study was undertaken to investigate the functional role and therapeutic potential of ENO1 in pancreatic cancer.

METHODS

We examined the expression levels of ENO1 across a broad spectrum of cancer types from the TCGA database. ENO1-knockout (ENO1-KO) through CRISPR/CAS9 technology in a mouse pancreatic cancer cell line (PAN02) was used to analyze the role of ENO1 on proliferation and colony formation. Flow cytometry and RT-PCR were also applied to analyze T lymphocytes and relevant cytokines.

RESULTS

In the present study, we identified that ENO1 promoted pancreatic cancer cell proliferation. Our bioinformatics data indicated that ENO1 was significantly overexpressed in pancreatic cancer cell lines and tissues. Survival analyses revealed that ENO1 overexpression implicated poor survival of PAAD patients. Knockout of ENO1 expression repressed the ability of proliferation and colony formation in PAN02. In addition, ENO1-KO significantly decreased tumor growth in mouse models. Further flow cytometry and RT-PCR analysis revealed that ENO1-KO modulates the tumor microenvironment (TME), especially in suppressed Treg cells and inducing anti-tumor cytokine responses.

CONCLUSIONS

Taken together, our data showed that ENO1 was an oncogenic biomarker and might serve as a promising target for immunotherapy of pancreatic cancer.

CDCA8/SNAI2 Complex Activates CD44 to Promote Proliferation and Invasion of Pancreatic Ductal Adenocarcinoma

Simple Summary

There is an urgent need to find an effective therapeutic target for pancreatic cancer owing to late diagnosis, tumor metastasis, and current ineffective targeted drugs. We aimed to identified potential targets for the treatment of pancreatic cancer. In this study, the specific mechanism by which the CDCA8 contributes to pancreatic cancer progression via the activation of CD44 was clarified, and CDCA8 knockdown inhibited the proliferation and metastasis of pancreatic cancer. This finding may provide a promising target for future targeted therapies of pancreatic cancer.

Abstract

(1) Background: Recently, cell division cycle associated 8 (CDCA8) was found to be overexpressed in pancreatic ductal adenocarcinoma (PDAC). Here, we aimed to explore the specific mechanism of action of CDCA8 in PDAC progression. (2) Methods: All human PDAC samples and clinical data were collected from Huashan Hospital, Fudan University. All experimental studies were carried out using many in vitro and in vivo assays, including lentiviral transfection, real-time quantitative polymerase chain reaction (qPCR), western blotting, co-immunoprecipitation (Co-IP), chromatin IP (ChIP)-qPCR, dual-luciferase reporter, and in vivo imaging assays. (3) Results: Clinical data analysis of human PDAC samples revealed that CDCA8 overexpression were positively and negatively associated with tumor grade (p = 0.007) and overall survival (p = 0.045), respectively. CDCA8 knockdown inhibited PDAC proliferation and invasion in in vitro and in vivo assays. CD44 was also up-regulated by CDCA8 during PDAC progression. CDCA8 could be combined with SNAI2 to form a CDCA8/SNAI2 complex to integrate with the CD44 promoter as indicated through ChIP-qPCR and dual-luciferase reporter assays. (4) Conclusion: We showed that CDCA8-CD44 axis plays a key role in the proliferation and invasion of PDAC, which provides a potential target for treatment.

C9orf16 represents the aberrant genetic programs and drives the progression of PDAC

Background

Pancreatic ductal adenocarcinoma (PDAC), constituting 90% of pancreatic cancers, is the fourth leading cause of cancer-related deaths in the world. Lack of early detection of PDAC contributes to its poor prognosis as patients are often diagnosed at an advanced stage of disease. This is mostly due to the lack of promising diagnostic and therapeutic targets and corresponding drugs.

Methods and results

Here, by bioinformatic analysis of single cell RNA-sequencing data on normal pancreas tissues, primary and metastatic PDAC tumors, we identified a promising PDAC biomarker, C9orf16. The expression of C9orf16, rarely detectable in normal epithelial cells, was upregulated in primary PDAC cancer cells and was further elevated in metastatic PDAC cancer cells. Gain or loss of function of C9orf16 demonstrated its critical functions in regulating the cell proliferation, invasion and chemotherapy resistance of cancer cells. Pathway analysis and functional studies identified MYC signaling pathways as the most activated pathways in regulating C9orf16 expression and in mediating the development and progression of PDAC.

Conclusions

These data suggested a crucial gene regulation system, MYC-C9orf16, which is actively involved in PDAC development and progression, and targeting this system should be a novel diagnostic and therapeutic target for PDAC.

Therapeutic advances in metastatic pancreatic cancer: a focus on targeted therapies

Mortality from pancreatic ductal adenocarcinoma (PDAC) is increasing worldwide and effective new treatments are urgently needed. The current treatment of metastatic PDAC in fit patients is based on two chemotherapy combinations (FOLFIRINOX and gemcitabine plus nab-paclitaxel) which were validated more than 8 years ago. Although almost all treatments targeting specific molecular alterations have failed so far when administered to unselected patients, encouraging results were observed in the small subpopulations of patients with germline BRCA 1/2 mutations, and somatic gene fusions (neurotrophic tyrosine receptor kinase, Neuregulin 1, which are enriched in KRAS wild-type PDAC), KRAS G12C mutations, or microsatellite instability. While targeted tumor metabolism therapies and immunotherapy have been disappointing, they are still under investigation in combination with other drugs. Optimizing pharmacokinetics and adapting available chemotherapies based on molecular signatures are other promising avenues of research. This review evaluates the current expectations and limits of available treatments and analyses the existing trials. A permanent search for actionable vulnerabilities in PDAC tumor cells and microenvironments will probably result in a more personalized therapeutic approach, keeping in mind that supportive care must also play a major role if real clinical efficacy is to be achieved in these patients.

Oncogenic KRAS-Induced Protein Signature in the Tumor Secretome Identifies Laminin-C2 and Pentraxin-3 as Useful Biomarkers for the Early Diagnosis of Pancreatic Cancer

KRAS mutations characterize pancreatic cell transformation from the earliest stages of carcinogenesis, and are present in >95% of pancreatic ductal adenocarcinoma (PDAC) cases. In search of novel biomarkers for the early diagnosis of PDAC, we identified the proteins secreted by the normal human pancreatic cell line (HPDE) recently transformed by inducing the overexpression of the KRASG12V oncogene. We report a proteomic signature of KRAS-induced secreted proteins, which was confirmed in surgical tumor samples from resected PDAC patients. The putative diagnostic performance of three candidates, Laminin-C2 (LAMC2), Tenascin-C (TNC) and Pentraxin-3 (PTX3), was investigated by ELISA quantification in two cohorts of PDAC patients (n = 200) eligible for surgery. Circulating levels of LAMC2, TNC and PTX3 were significantly higher in PDAC patients compared to the healthy individuals (p < 0.0001). The Receiver Operating Characteristics (ROC) curve showed good sensitivity (1) and specificity (0.63 and 0.85) for LAMC2 and PTX3, respectively, but not for TNC, and patients with high levels of LAMC2 had significantly shorter overall survival (p = 0.0007). High levels of LAMC2 and PTX3 were detected at early stages (I−IIB) and in CA19-9-low PDAC patients. In conclusion, pancreatic tumors release LAMC2 and PTX3, which can be quantified in the systemic circulation, and may be useful in selecting patients for further diagnostic imaging.

[Pathological processing in pancreatic ductal adenocarcinoma-What is new?]

The macroscopic and microscopic assessments of pancreatic cancer resection specimens belong to the standard repertoire of any department of pathology. In recent years standards have been developed regarding both macroscopic and microscopic assessments, which are laid down in international and national guidelines and classifications and are regularly updated. In this way the reporting of results and interdisciplinary communication are facilitated. These classifications and guidelines are influenced by current studies and the data from them provide information on which histopathological factors are particularly relevant for the prognosis and treatment. Due to the increasing use of neoadjuvant therapy the assessment of tumor regression in histopathological specimens is also gaining in importance. Finally, individual targeted treatments are also now available for pancreatic cancer, which require extended molecular pathological diagnostics.

Oxidative Stress Markers Are Associated with a Poor Prognosis in Patients with Pancreatic Cancer

Pancreatic cancer is a malignancy of rising prevalence, especially in developed countries where dietary patterns and sedentariness favor its onset. This malady ranks seventh in cancer-related deaths in the world, although it is expected to rank second in the coming years, behind lung cancer. The low survival rate is due to the asymptomatic course of the early stages, which in many cases leads to metastases when becoming evident in advanced stages. In this context, molecular pathology is on the way towards finding new approaches with biomarkers that allow a better prognosis and monitoring of patients. So the present study aims to evaluate a series of molecular biomarkers, PARP1, NOX1, NOX2, eNOS and iNOS, as promising candidates for prognosis and survival by using immunohistochemistry. The analysis performed in 41 patients with pancreatic cancer showed a correlation between a high expression of all these components with a low survival rate, with high statistical power for all. In addition, a 60-month longitudinal surveillance program was managed, accompanied by several clinical parameters. The derivative Kaplan–Meier curves indicated a low cumulative survival rate as well. Ultimately, our research emphasized the value of these molecules as survival-associated biomarkers in pancreatic cancer, offering new gates for clinical management.

Recent advances in artificial intelligence for pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains the most lethal type of cancer. The 5-year survival rate for patients with early-stage diagnosis can be as high as 20%, suggesting that early diagnosis plays a pivotal role in the prognostic improvement of PDAC cases. In the medical field, the broad availability of biomedical data has led to the advent of the "big data" era. To overcome this deadly disease, how to fully exploit big data is a new challenge in the era of precision medicine. Artificial intelligence (AI) is the ability of a machine to learn and display intelligence to solve problems. AI can help to transform big data into clinically actionable insights more efficiently, reduce inevitable errors to improve diagnostic accuracy, and make real-time predictions. AI-based omics analyses will become the next alterative approach to overcome this poor-prognostic disease by discovering biomarkers for early detection, providing molecular/genomic subtyping, offering treatment guidance, and predicting recurrence and survival. Advances in AI may therefore improve PDAC survival outcomes in the near future. The present review mainly focuses on recent advances of AI in PDAC for clinicians. We believe that breakthroughs will soon emerge to fight this deadly disease using AI-navigated precision medicine.

hENT1 Predicts Benefit from Gemcitabine in Pancreatic Cancer but Only with Low CDA mRNA

Gemcitabine or 5-fluorouracil (5-FU) based treatments can be selected for pancreatic cancer. Equilibrative nucleoside transporter 1 (hENT1) predicts adjuvant gemcitabine treatment benefit over 5-FU. Cytidine deaminase (CDA), inside or outside of the cancer cell, will deaminate gemcitabine, altering transporter affinity. ESPAC-3(v2) was a pancreatic cancer trial comparing adjuvant gemcitabine and 5-FU. Tissue microarray sections underwent in situ hybridization and immunohistochemistry. Analysis of both CDA and hENT1 was possible with 277 patients. The transcript did not correlate with protein levels for either marker. High hENT1 protein was prognostic with gemcitabine; median overall survival was 26.0 v 16.8 months (p = 0.006). Low CDA transcript was prognostic regardless of arm; 24.8 v 21.2 months with gemcitabine (p = 0.02) and 26.4 v 14.6 months with 5-FU (p = 0.02). Patients with low hENT1 protein did better with 5-FU, but only if the CDA transcript was low (median survival of 5-FU v gemcitabine; 29.3 v 18.3 months, compared with 14.2 v 14.6 with high CDA). CDA mRNA is an independent prognostic biomarker. When added to hENT1 protein status, it may also provide treatment-specific predictive information and, within the frame of a personalized treatment strategy, guide to either gemcitabine or 5FU for the individual patient.

Identification of 2 Chinese Primary Pancreatic Ductal Adenocarcinoma Cancer Cell Lines and Their Phenotypes

OBJECTIVES

Pancreatic cancer (PC) is one of the most lethal cancers. Currently, the most commonly used PC cell lines were all derived from White individuals, and few models can be used to study in Asian populations. In China, the incidence of PC is increasing every year, highlighting the need to develop new Chinese PC cell lines for cancer research.

METHODS

A total of 203 patients diagnosed with PC, enrolled from January 2012 to December 2017 in our hospital (Department of Hepatobiliary and Pancreatic Surgery), had received surgery. Primary PC patient tumor samples were harvested sterilely from surgery, minced, and digested in collagenase. Cells were cultured in plates precoated with l-polylysine.

RESULTS

Two primary PC cell lines, Si-Liang 187 and Si-Liang 188, were established, both of which grew as adherent monolayers and demonstrated distinguished phenotypes. Si-Liang 187 shows the typical mesenchymal pattern, whereas Si-Liang 188 shows epithelial phenotype. Moreover, they carry different genetic backgrounds according to whole exome sequencing.

CONCLUSIONS

Two new Chinese PC cell lines were established, both of which were characterized and confirmed with high tumorigenicity. They may serve as useful tools for pathogenesis research when evaluating new treatment strategies in Asian patients.

The Role of Circulating MicroRNAs in Patients with Early-Stage Pancreatic Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is increasing in incidence and is still associated with a high rate of mortality. Only a minority of patients are diagnosed in the early stage. Radical surgery is the only potential curative procedure. However, radicality is reached in 20% of patients operated on. Despite the multidisciplinary approach in resectable tumors, early tumor recurrences are common. Options on how to select optimal candidates for resection remain limited. Nevertheless, accumulating evidence shows an important role of circulating non-coding plasma and serum microRNAs (miRNAs), which physiologically regulate the function of a target protein. miRNAs also play a crucial role in carcinogenesis. In PDAC patients, the expression levels of certain miRNAs vary and may modulate the function of oncogenes or tumor suppressor genes. As they can be detected in a patient's blood, they have the potential to become promising non-invasive diagnostic and prognostic biomarkers. Moreover, they may also serve as markers of chemoresistance. Thus, miRNAs could be useful for early and accurate diagnosis, prognostic stratification, and individual treatment planning. In this review, we summarize the latest findings on miRNAs in PDAC patients, focusing on their potential use in the early stage of the disease.

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).

Non-coding RNAs in pancreatic ductal adenocarcinoma: New approaches for better diagnosis and therapy

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies with a 5-year survival rate less than 8%, which has remained unchanged over the last 50 years. Early detection is particularly difficult due to the lack of disease-specific symptoms and a reliable biomarker. Multimodality treatment including chemotherapy, radiotherapy (used sparingly) and surgery has become the standard of care for patients with PDAC. Carbohydrate antigen 19-9 (CA 19-9) is the most common diagnostic biomarker; however, it is not specific enough especially for asymptomatic patients. Non-coding RNAs are often deregulated in human malignancies and shown to be involved in cancer-related mechanisms such as cell growth, differentiation, and cell death. Several micro, long non-coding and circular RNAs have been reported to date which are involved in PDAC. Aim of this review is to discuss the roles and functions of non-coding RNAs in diagnosis and treatments of PDAC.

Development of a novel multi-functional integrated bioconjugate that effectively targets K-Ras mutant pancreatic cancer

Folate receptor (FR) overexpression occurs in a variety of cancers, including pancreatic cancer. In addition, enhanced macropinocytosis exists in K-Ras mutant pancreatic cancer. Furthermore, the occurrence of intensive desmoplasia causes a hypoxic microenvironment in pancreatic cancer. In this study, a novel FR-directed, macropinocytosis-enhanced, and highly cytotoxic bioconjugate folate (F)-human serum albumin (HSA)-apoprotein of lidamycin (LDP)-active enediyne (AE) derived from lidamycin was designed and prepared. F-HSA-LDP-AE consisted of four moieties: F, HSA, LDP, and AE. F-HSA-LDP presented high binding efficiency with the FR and pancreatic cancer cells. Its uptake in wild-type cells was more extensive than in K-Ras mutant-type cells. By in vivo optical imaging, F-HSA-LDP displayed prominent tumor-specific biodistribution in pancreatic cancer xenograft-bearing mice, showing clear and lasting tumor localization for 360 h. In the MTT assay, F-HSA-LDP-AE demonstrated potent cytotoxicity in three types of pancreatic cancer cell lines. It also induced apoptosis and caused G2/M cell cycle arrest. F-HSA-LDP-AE markedly suppressed the tumor growth of AsPc-1 pancreatic cancer xenografts in athymic mice. At well-tolerated doses of 0.5 and 1 mg/kg, (i.v., twice), the inhibition rates were 91.2% and 94.8%, respectively (P<0.01). The results of this study indicate that the F-HSA-LDP multi-functional bioconjugate might be effective for treating K-Ras mutant pancreatic cancer.

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We designed and generated a folate receptor-targeted and macropinocytosis-enhanced recombinant protein conjugate.

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F-HSA-LDP displayed highly specific biodistribution and long-lasting tumor accumulation in pancreatic cancer cells.

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F-HSA-LDP-AE induced apoptosis and G2/M cell cycle arrest and markedly suppressed the growth of pancreatic cancer cells.

Immune Stimulating Antibody-Photosensitizer Conjugates via Fc-Mediated Dendritic Cell Phagocytosis and Phototriggered Immunogenic Cell Death for KRAS-Mutated Pancreatic Cancer Treatment

Although cetuximab (CTX) is a chimeric epidermal growth factor receptor (EGFR) antibody, the antitumor efficacy of CTX has a negligible effect in patients with Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) mutated pancreatic adenocarcinoma. Given that all extant treatments are ineffective due to the undruggable characteristics of KRAS-mutated cancer, alternative strategies have been investigated. In this work, CTX-conjugated maleimide-polyethylene glycol-chlorin e6 (CMPC) is designed to strengthen its antitumor efficacy. With strong affinity for EGFR overexpressing Aspc-1 cells, CMPC with laser exerts the greatest cytotoxicity (90%) and induction of immunogenic cell death. Through a combination of fragment crystallizable region-mediated antigen uptake by CTX and danger-associated molecular patterns released by photodynamic therapy (PDT), phagocytosis and maturation of dendritic cells treated with CMPC plus laser show dramatic increases. In vivo biodistribution and antitumor effect also demonstrate that CMPC has significant tumor selectivity and tumor ablation efficacy upon laser irradiation. Furthermore, a large number of CD4⁺ , CD8⁺ T cells and mature DCs and natural killer cells are infiltrated in CMPC with laser-treated tumor tissues and tumor-draining lymph nodes, revealing both innate and adaptive cellular immune stimulation. This synergistic effect with CMPC and laser treatment provides an effective approach for pancreatic cancer immunotherapy attributed to both CTX and PDT.

Blood-based extracellular matrix biomarkers as predictors of survival in patients with metastatic pancreatic ductal adenocarcinoma receiving pegvorhyaluronidase alfa

Background

Extensive extracellular matrix (ECM) remodeling is a hallmark of metastatic pancreatic ductal adenocarcinoma (mPDA). We investigated fragments of collagen types III (C3M, PRO-C3), VI (PRO-C6), and VIII (C8-C), and versican (VCANM) in plasma as biomarkers for predicting progression-free survival (PFS) and overall survival (OS) in patients with mPDA treated with pegvorhyaluronidase alfa, a biologic that degrades the ECM component hyaluronan (HA), in a randomized phase 2 study (HALO109-202).

Methods

HALO109-202 comprised a discovery cohort (Stage 1, n = 94) and a validation cohort (Stage 2, n = 95). Plasma ECM biomarkers were analyzed by ELISAs. Univariate Cox regression analysis and Kaplan–Meier plots evaluated predictive associations between biomarkers, PFS and OS in patients treated with pegvorhyaluronidase alfa plus nab-paclitaxel/gemcitabine (PAG) versus nab-paclitaxel/gemcitabine (AG) alone.

Results

PFS was improved with PAG vs. AG in Stage 1 patients with high C3M/PRO-C3 ratio (median cut-off): median PFS (mPFS) 8.0 vs. 5.3 months, P = 0.031; HR = 0.40; 95% CI 0.17–0.92). High C3M/PRO-C3 ratio was validated in Stage 2 patients by predicting a PFS benefit of PAG vs. AG (mPFS: 8.8 vs. 3.4 months, P = 0.046; HR = 0.46; 95% CI 0.21–0.98). OS was also improved in patients with high C3M/PRO-C3 ratio treated with PAG vs. AG (mOS 13.8 vs 8.5 months, P = 0.009; HR = 0.35; 95% CI 0.16–0.77). Interestingly, high C3M/PRO-C3 ratio predicted for a PFS benefit to PAG vs. AG both in patients with HA-low tumors (HR = 0.36; 95% CI 0.17–0.79) and HA-high tumors (HR = 0.20; 95% CI 0.06–0.69).

Conclusions

The C3M/PRO-C3 ratio measuring type III collagen turnover in plasma has potential as a blood-based predictive biomarker in patients with mPDA and provides additional value to a HA biopsy when applied for patient selection.

Trial registration: NCT01839487. Registered 25 April 2016

Implementing biological markers as a tool to guide clinical care of patients with pancreatic cancer

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A major obstacle for the effective treatment of PDAC is its molecular heterogeneity.

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Stratification of PDAC using markers highly specific, reproducible, sensitive, easily measurable and inexpensive is necessary.

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At the early stages, clinician’s priority lies in rapid diagnosis, so that the patient receives surgery without delay.

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At advanced disease stages, priority is to determine the tumor subtype and select a suitable effective treatment.

A major obstacle for the effective treatment of pancreatic ductal adenocarcinoma (PDAC) is its molecular heterogeneity, reflected by the diverse clinical outcomes and responses to therapies that occur. The tumors of patients with PDAC must therefore be closely examined and classified before treatment initiation in order to predict the natural evolution of the disease and the response to therapy. To stratify patients, it is absolutely necessary to identify biological markers that are highly specific and reproducible, and easily measurable by inexpensive sensitive techniques. Several promising strategies to find biomarkers are already available or under development, such as the use of liquid biopsies to detect circulating tumor cells, circulating free DNA, methylated DNA, circulating RNA, and exosomes and extracellular vesicles, as well as immunological markers and molecular markers. Such biomarkers are capable of classifying patients with PDAC and predicting their therapeutic sensitivity. Interestingly, developing chemograms using primary cell lines or organoids and analyzing the resulting high-throughput data via artificial intelligence would be highly beneficial to patients. How can exploiting these biomarkers benefit patients with resectable, borderline resectable, locally advanced, and metastatic PDAC? In fact, the utility of these biomarkers depends on the patient's clinical situation. At the early stages of the disease, the clinician's priority lies in rapid diagnosis, so that the patient receives surgery without delay; at advanced disease stages, where therapeutic possibilities are severely limited, the priority is to determine the PDAC tumor subtype so as to estimate the clinical outcome and select a suitable effective treatment.

Leukemia inhibitory factor is a novel biomarker to predict lymph node and distant metastasis in pancreatic cancer

Pancreatic cancer has a low survival rate, and most patients have lymph node metastasis and distant metastasis at the time of diagnosis. Despite efforts to improve overall survival (OS) and recurrence free survival (RFS), the prognosis of pancreatic cancer remains poor, underscoring the importance of identifying new biomarkers to predict metastasis in patients with pancreatic cancer. Leukemia inhibitory factor (LIF) is overexpressed in many types of cancer and is involved in the development of various malignancies including pancreatic cancer. However, the role of LIF as a biomarker to predict metastasis in pancreatic cancer remains unclear. In this study, univariate and multivariate Cox regression analyses identified LIF expression in pancreatic tumor tissues as an independent risk factor related to worse OS and RFS. LIF overexpression was related to poor clinicopathological features such as lymph node metastasis and Pathological stage (pTNM) stage. Serum LIF levels were higher in pancreatic cancer patients than in healthy controls. The area under the receiver operating characteristic curve indicated that serum LIF is more effective than other biomarkers (CA199 and CEA) for predicting lymph node and distant metastasis.

A machine learning approach identified a diagnostic model for pancreatic cancer through using circulating microRNA signatures

Late diagnosis of pancreatic cancer (PC) due to the limited effectiveness of modern testing approaches, causes many patients to miss the chance of surgery and consequently leads to a high mortality rate. Pivotal improvements in circulating microRNA expression levels in PC patients make it possible to diagnose and treat patients at earlier stages. A list of circulating miRNAs was identified in this study using bioinformatics methods in association with pancreatic cancer through analyzing four GEO microarray datasets. The value of top miRNAs was then assessed via using a machine learning method. Taking the advantage of a combinatorial approach consisting of Particle Swarm Optimization (PSO) + Artificial Neural Network (ANN) and Neighborhood Component Analysis (NCA) iterations on a collection of top differentially expressed circulating miRNAs in PC patients, facilitated ranking them by significance. MiRNA's functional analysis in the final index was performed by predicting target genes and constructing PPI networks. Remarkably, the final model consist of miR-663a, miR-1469, miR-92a-2-5p, miR-125b-1-3p and miR-532-5p showed great diagnostic results on investigated cases and the validation set (Accuracy: 0.93, Sensitivity: 0.93, and Specificity: 0.92). Kaplan-Meier survival assessments of the top-ranked miRNAs revealed that three miRNAs, hsa-miR-1469, hsa-miR-663a and hsa-miR-532-5p, had meaningful associations with the prognosis of patients with pancreatic cancer. This miRNA index may serve as a non-invasive and potential PC diagnostic model, although experimental testing is needed.

LncRNA PCAT6 promotes the proliferation, migration and invasion of pancreatic ductal adenocarcinoma via regulating miR-185-5p/CBX2 axis

Emerging evidence has revealed markedly roles for long noncoding RNAs (lncRNAs) in various cancer processes. Prostate cancer associated transcript 6 (PCAT6) is a novel lncRNA which displays vital regulatory functions in multiple cancers. However, the functions of PCAT6 in pancreatic ductal adenocarcinoma (PDAC) remain unclear. Our study confirmed that PCAT6 expression was upregulated in PDAC and the expression of PCAT6 was related to TNM stage, lymph node invasion and overall survival of PDAC patients. PCAT6 might act as an effective tumor biomarker for PDAC patients. Moreover, knockdown of PCAT6 inhibited cell proliferation, migration and invasion of PDAC in vitro. For the mechanism, miR-185-5p expression was decreased and chromobox 2 (CBX2) expression was increased in PDAC, and further PCAT6 could upregulated the expression of oncogene CBX2 by sponging miR-185-5p. The results above suggested that PCAT6/miR-185-5p/CBX2 exerted crucial functions in tumorigenesis and progression of PDAC.

Mucins in pancreatic cancer: A well-established but promising family for diagnosis, prognosis and therapy

Mucins are a family of multifunctional glycoproteins that mostly line the surface of epithelial cells in the gastrointestinal tract and exert pivotal roles in gut lubrication and protection. Pancreatic cancer is a lethal disease with poor early diagnosis, limited therapeutic effects, and high numbers of cancer‐related deaths. In this review, we introduce the expression profiles of mucins in the normal pancreas, pancreatic precursor neoplasia and pancreatic cancer. Mucins in the pancreas contribute to biological processes such as the protection, lubrication and moisturization of epithelial tissues. They also participate in the carcinogenesis of pancreatic cancer and are used as diagnostic biomarkers and therapeutic targets. Herein, we discuss the important roles of mucins that lead to the lethality of pancreatic adenocarcinoma, particularly MUC1, MUC4, MUC5AC and MUC16 in disease progression, and present a comprehensive analysis of the clinical application of mucins and their promising roles in cancer treatment to gain a better understanding of the role of mucins in pancreatic cancer.

Matrix Metalloproteinase 11 as a Novel Tumor Promoter and Diagnostic and Prognostic Biomarker for Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Matrix metalloproteinase 11 (MMP-11) was found to be implicated in tumorigenesis in cancers. However, the significance of MMP-11 in pancreatic ductal adenocarcinoma (PDAC) is unclear.

METHODS

In the study, we detected malignant biological behaviors of pancreatic cancer after downregulation of MMP-11. Furthermore, we explored the possible mechanism, and the diagnostic value of serum MMP-11 level was analyzed in 116 patients with pathologically confirmed PDAC. In addition, we explored their prognostic value in PDAC.

RESULTS

We observed that MMP-11 could be expressed and activated in the cytoplasm of PDAC cells. Immunohistochemistry staining of PDAC tissues showed that MMP-11 was highly expressed in cancerous ductal epithelium instead of cancer stroma. We found that downregulation of MMP-11 inhibited proliferation of PDAC cell lines. The expression levels of cyclin-dependent kinase 4 and cyclin D1 were downregulated after MMP-11 knockdown. As for its clinical value, the serum level of MMP-11 was shown to be a potent promising diagnostic marker for PDAC.

CONCLUSIONS

Matrix metalloproteinase 11 may act as a tumor promoter, playing a positive role in PDAC development. Serum MMP-11 also has great potential to be a promising diagnostic marker for PDAC.

Overexpression of MYEOV predicting poor prognosis in patients with pancreatic ductal adenocarcinoma

Myeloma Overexpressed (MYEOV) is closely related to cell growth and differentiation in many cancer types. However, the role of this protein-coding gene in pancreatic ductal adenocarcinoma (PDAC) has rarely been investigated. In this study, we demonstrated that MYEOV was higher expressed in tumor tissues compared with adjacent normal pancreas tissues (ANPTs) both in mRNA and protein levels. We also performed bioinformatic analysis and found high MYEOV expression was positively correlated with tumor differentiation (P = 0.004), lymph node metastasis (P = 0.016) and TNM stage (P = 0.001). Moreover, Kaplan-Meier and Cox proportional-hazards analyses indicated that high MYEOV expression was significantly associated with poor survival in patients with PDAC and that MYEOV was an independent prognostic factor for overall survival in patients with PDAC. Geneset Enrichment Analysis (GSEA) result showed that high expression of MYEOV facilitates glycolysis of tumor cells in PDAC and validated in cellular assays. In conclusion, our results suggest that MYEOV acts as an oncogene in PDAC and can therefore serve as a biomarker for the prognosis of patients with PDAC.

Next-Generation Manufacturing Protocols Enriching TSCM CAR T Cells Can Overcome Disease-Specific T Cell Defects in Cancer Patients

Chimeric antigen receptor (CAR) T cell expansion and persistence emerged as key efficacy determinants in cancer patients. These features are typical of early-memory T cells, which can be enriched with specific manufacturing procedures, providing signal one and signal two in the proper steric conformation and in the presence of homeostatic cytokines. In this project, we exploited our expertise with paramagnetic beads and IL-7/IL-15 to develop an optimized protocol for CAR T cell production based on reagents, including a polymeric nanomatrix, which are compatible with automated manufacturing via the CliniMACS Prodigy. We found that both procedures generate similar CAR T cell products, highly enriched of stem cell memory T cells (T_SCM) and equally effective in counteracting tumor growth in xenograft mouse models. Most importantly, the optimized protocol was able to expand CAR T_SCM from B-cell acute lymphoblastic leukemia (B-ALL) patients, which in origin were highly enriched of late-memory and exhausted T cells. Notably, CAR T cells derived from B-ALL patients proved to be as efficient as healthy donor-derived CAR T cells in mediating profound and prolonged anti-tumor responses in xenograft mouse models. On the contrary, the protocol failed to expand fully functional CAR T_SCM from patients with pancreatic ductal adenocarcinoma, suggesting that patient-specific factors may profoundly affect intrinsic T cell quality. Finally, by retrospective analysis of in vivo data, we observed that the proportion of T_SCM in the final CAR T cell product positively correlated with in vivo expansion, which in turn proved to be crucial for achieving long-term remissions. Collectively, our data indicate that next-generation manufacturing protocols can overcome initial T cell defects, resulting in T_SCM-enriched CAR T cell products qualitatively equivalent to the ones generated from healthy donors. However, this positive effect may be decreased in specific conditions, for which the development of further improved protocols and novel strategies might be highly beneficial.

SST gene hypermethylation acts as a pan-cancer marker for pancreatic ductal adenocarcinoma and multiple other tumors: toward its use for blood-based diagnosis

Aberrant DNA methylation is often involved in carcinogenesis. Our initial goal was to identify DNA methylation biomarkers associated with pancreatic cancer. A genomewide methylation study was performed on DNA from pancreatic ductal adenocarcinoma (PDAC) and endocrine pancreas tumors. Validation of DNA methylation patterns and concomitant alterations in expression of gene candidates was performed on patient samples and pancreatic cancer cell lines. Furthermore, validation was done on independent data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Finally, droplet digital PCR was employed to detect DNA methylation marks in cell-free (cf) DNA isolated from plasma samples of PDAC patients and cancer-free blood donors. Hypermethylation of the SST gene (encoding somatostatin) and concomitant downregulation of its expression were discovered in PDAC and endocrine tumor tissues while not being present in chronic pancreatitis (inflamed) tissues and normal pancreas. Fittingly, treatment with a somatostatin agonist (octreotide) reduced cell proliferation and migration of pancreatic cancer cells. Diagnostic performance of SST methylation in a receiver operating characteristic curve analysis was 100% and 89% for tissue and plasma samples, respectively. A large body of TCGA and GEO data confirmed SST hypermethylation and downregulation in PDAC and showed a similar effect in a broad spectrum of other tumor entities. SST promoter methylation represents a sensitive and promising molecular, pan-cancer biomarker detectable in tumor tissue, and liquid biopsy samples.

TGFβ Signaling Increases Net Acid Extrusion, Proliferation and Invasion in Panc-1 Pancreatic Cancer Cells: SMAD4 Dependence and Link to Merlin/NF2 Signaling

Pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer-related death, with a 5-year survival of <10% and severely limited treatment options. PDAC hallmarks include profound metabolic acid production and aggressive local proliferation and invasiveness. This phenotype is supported by upregulated net acid extrusion and epithelial-to-mesenchymal transition (EMT), the latter typically induced by aberrant transforming growth factor-β (TGFβ) signaling. It is, however, unknown whether TGFβ-induced EMT and upregulation of acid extrusion are causally related. Here, we show that mRNA and protein expression of the net acid extruding transporters Na⁺/H⁺ exchanger 1 (NHE1, SLC9A1) and Na⁺, HCO3- cotransporter 1 (NBCn1, SLC4A7) are increased in a panel of human PDAC cell lines compared to immortalized human pancreatic ductal epithelial (HPDE) cells. Treatment of Panc-1 cells (which express SMAD4, required for canonical TGFβ signaling) with TGFβ-1 for 48 h elicited classical EMT with down- and upregulation of epithelial and mesenchymal markers, respectively, in a manner inhibited by SMAD4 knockdown. Accordingly, less pronounced EMT was induced in BxPC-3 cells, which do not express SMAD4. TGFβ-1 treatment elicited a SMAD4-dependent increase in NHE1 expression, and a smaller, SMAD4-independent increase in NBCn1 in Panc-1 cells. Consistent with this, TGFβ-1 treatment led to elevated intracellular pH and increased net acid extrusion capacity in Panc-1 cells, but not in BxPC-3 cells, in an NHE1-dependent manner. Proliferation was increased in Panc-1 cells and decreased in BxPC-3 cells, upon TGFβ-1 treatment, and this, as well as EMT per se, was unaffected by NHE1- or NBCn1 inhibition. TGFβ-1-induced EMT was associated with a 4-fold increase in Panc-1 cell invasiveness, which further increased ~10-fold upon knockdown of the tumor suppressor Merlin (Neurofibromatosis type 2). Knockdown of NHE1 or NBCn1 abolished Merlin-induced invasiveness, but not that induced by TGFβ-1 alone. In conclusion, NHE1 and NBCn1 expression and NHE-dependent acid extrusion are upregulated during TGFβ-1-induced EMT of Panc-1 cells. NHE1 upregulation is SMAD4-dependent, and SMAD4-deficient BxPC-3 cells show no change in pH_i regulation. NHE1 and NBCn1 are not required for EMT per se or EMT-associated proliferation changes, but are essential for the potentiation of invasiveness induced by Merlin knockdown.

The Serum MicroRNA Signatures for Pancreatic Cancer Detection and Operability Evaluation

Pancreatic cancer (PC) has high morbidity and mortality. It is the fourth leading cause of cancer death. Its diagnosis and treatment are difficult. Liquid biopsy makes early diagnosis of pancreatic cancer possible. We analyzed the expression profiles of 2,555 serum miRNAs in 100 pancreatic cancer patients and 150 healthy controls. With advanced feature selection methods, we identified 13 pancreatic cancer signature miRNAs that can classify the pancreatic cancer patients and healthy controls. For pancreatic cancer treatment, operation is still the first choice. But many pancreatic cancer patients are already inoperable. Therefore, we compared the 79 inoperable and 21 operable patients and identified 432 miRNAs that can predict whether a pancreatic cancer patient was operable. The functional analysis of the 13 pancreatic cancer signatures and the 432 operability miRNAs revealed the molecular mechanisms of pancreatic cancer and shield light on the diagnosis and therapy of pancreatic cancer in clinical practice.

Patient-derived xenograft model engraftment predicts poor prognosis after surgery in patients with pancreatic cancer

OBJECTIVES

To establish and evaluate a first generation patient-derived xenograft (PDX) model in nude mice using tumors resected from pancreatic cancer (PC) patients for the identification of key factors that influence xenograft success and prediction of patient prognosis.

METHODS

Primary tumor samples harvested from PC patients who underwent curative resection between May 2016 and April 2018 at our hospital were xenografted into nude mice. Tumor size was evaluated for 2 months. Patients' baseline characteristics and follow-up data were analyzed.

RESULTS

Tumor xenograft models were generated from 67 patients; 30 (44.8%) were successful and 37 (55.2%) failed. Xenograft models could recapitulate the pathology and genetic information of the primary tumors. Univariate analysis identified tumor engraftment, post-operation CA19-9, tumor size, lymph node status, and lymphovascular invasion as significant predictors (P=0.000, 0.023, 0.004, 0.035 and 0.005, respectively) of disease-free survival (DFS). Multivariate Cox regression analysis confirmed tumor engraftment, tumor size and lymphovascular invasion function as independent risk factors for DFS (P=0.000, 0.039 and 0.025, respectively). The hazard ratio of tumor engraftment for DFS was 0.239 (95% confidence interval, 0.109 to 0.524). Kaplan-Meier analysis of DFS indicated an unfavorable outcome in the engraftment group compared to that in the failed engraftment group (6.2 vs. 12.2 months, log rank P=0.000).

CONCLUSION

The pathology and genetic information of primary PC tumors are recapitulated in the PDX tumor model in nude mice. Furthermore, engraftment success is an effective predictor of disease recurrence in patients after surgery.

PROM2 promotes gemcitabine chemoresistance via activating the Akt signaling pathway in pancreatic cancer

In recent years, the deoxycytidine analogue gemcitabine (2′,2′,-difluorodeoxycytidine) has become the first-line chemotherapeutic agent for patients with pancreatic cancer. However, due to the intrinsic resistance of pancreatic cancer cells, gemcitabine-based chemotherapy yields limited disease control, with >85% disease progression at 6 months from diagnosis. Therefore, elucidating the mechanisms of chemoresistance is a critical step in improving cancer therapy, especially for the treatment of pancreatic cancer. We show PROM2, a transmembrane glycoprotein, is ubiquitously upregulated in pancreatic cancer cell. We also found higher PROM2 expression is associated with shortened overall and disease-free survival times in patients diagnosed with pancreatic cancer. We provide evidence that PROM2 promotes chemoresistance to gemcitabine both in vivo and in vitro. Mechanistically, we demonstrate that PROM2 could directly interacted with Akt and activates the Akt signaling pathway, which thus inhibiting gemcitabine-induced apoptosis. As further evidence, we show PROM2 expression and Akt phosphorylation both promote gemcitabine chemoresistance, and cause poorer survival in clinical samples with pancreatic cancer. Combining gemcitabine with the Akt inhibitor MK-2206 facilitated significant tumor shrinkage and dramatically elevated the survival status in mice xenografted with pancreatic cancer cells. Our findings not only establish PROM2 as a novel positive regulator of the Akt signaling pathway and a candidate prognostic indicator of gemcitabine response, but also provide a neo-therapeutic approach for patients resistant to gemcitabine treatment.

A cell membrane protein called PROM2 promotes the resistance of pancreatic cancer to the anti-cancer drug gemcitabine, suggesting PROM2 and the molecular signaling pathway it stimulates could be targeted by new treatments. Researchers in China led by Jian Sun at Sun Yat-Sen University, Guangzhou, investigated the role of PROM2 in cultured human pancreatic cancer cells and in a mouse model of pancreatic cancer. Production and activity of PROM2 were increased in cancer cells, leading to increased resistance to gemcitabine. The researchers found that PROM2’s promotion of gemcitabine resistance was linked to its ability to bind to another protein called Akt. This interaction stimulates the Akt signaling pathway, sustaining cancer cells. Combining gemcitabine therapy with an Akt pathway inhibitor restored cancer cell sensitivity to gemcitabine, revealing a potential approach to developing drugs to overcome gemcitabine resistance.

Role of oncogenic KRAS in the diagnosis, prognosis and treatment of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is predicted to be the second most common cause of death within the next 10 years. The prognosis for this disease is poor despite diagnostic progress and new chemotherapeutic regimens. The oncogenic KRAS mutation is the major event in pancreatic cancer; it confers permanent activation of the KRAS protein, which acts as a molecular switch to activate various intracellular signalling pathways and transcription factors inducing cell proliferation, migration, transformation and survival. Several laboratory methods have been developed to detect KRAS mutations in biological samples, including digital droplet PCR (which displays high sensitivity). Clinical studies have revealed that a KRAS mutation assay in fine-needle aspiration material combined with cytopathology increases the sensitivity, accuracy and negative predictive value of cytopathology for a positive diagnosis of pancreatic cancer. In addition, the presence of KRAS mutations in serum and plasma (liquid biopsies) correlates with a worse prognosis. The presence of mutated KRAS can also have therapeutic implications, whether at the gene level per se, during its post-translational maturation, interaction with nucleotides and after activation of the various oncogenic signals. Further pharmacokinetic and toxicological studies on new molecules are required, especially small synthetic molecules, before they can be used in the therapeutic arsenal for pancreatic ductal adenocarcinoma.

RNA cargos in extracellular vesicles derived from blood serum in pancreas associated conditions

Exosomes are extracellular vesicles which are released from healthy and tumor cells into blood circulation. Unique biomolecular cargos such as RNA and protein are loaded in these vesicles. These molecules may have biological functions such as signaling, cell communications and have the potential to be analyzed as biomarkers. In this initial study, we describe the analysis of exosomes in the serum of healthy subjects, intraductal papillary mucosal neoplasms and pancreatic ductal adenocarcinoma including the characterization of their RNA cargos by next generation sequencing (EXO-NGS). Results indicate the presence of a wide variety of RNAs including mRNA, miRNA, lincRNA, tRNA and piRNA in these vesicles. Based on the differential mRNA expression observed upon EXO-NGS analysis, we independently evaluated two protein coding genes, matrix metalloproteinase-8 (MMP-8) and transcription factor T-Box 3 (TBX3) by qRT-PCR for selective expression in the serum samples. Results indicate a variable expression pattern of these genes across serum samples between different study groups. Further, qRT-PCR analysis with the same serum exosomes processed for EXO-NGS, we observed two long non-coding RNAs, malat-1 and CRNDE to be variably expressed. Overall, our observations emphasize the potential value of different exosome components in distinguishing between healthy, premalignant and malignant conditions related to the pancreas.

Metabolome of Pancreatic Juice Delineates Distinct Clinical Profiles of Pancreatic Cancer and Reveals a Link between Glucose Metabolism and PD-1+ Cells

Better understanding of pancreatic diseases, including pancreatic ductal adenocarcinoma (PDAC), is an urgent medical need, with little advances in preoperative differential diagnosis, preventing rational selection of therapeutic strategies. The clinical management of pancreatic cancer patients would benefit from the identification of variables distinctively associated with the multiplicity of pancreatic disorders. We investigated, by ¹H nuclear magnetic resonance, the metabolomic fingerprint of pancreatic juice (the biofluid that collects pancreatic products) in 40 patients with different pancreatic diseases. Metabolic variables discriminated PDAC from other less aggressive pancreatic diseases and identified metabolic clusters of patients with distinct clinical behaviors. PDAC specimens were overtly glycolytic, with significant accumulation of lactate, which was probed as a disease-specific variable in pancreatic juice from a larger cohort of 106 patients. In human PDAC sections, high expression of the glucose transporter GLUT-1 correlated with tumor grade and a higher density of PD-1⁺ T cells, suggesting their accumulation in glycolytic tumors. In a preclinical model, PD-1⁺ CD8 tumor-infiltrating lymphocytes differentially infiltrated PDAC tumors obtained from cell lines with different metabolic consumption, and tumors metabolically rewired by knocking down the phosphofructokinase (Pfkm) gene displayed a decrease in PD-1⁺ cell infiltration. Collectively, we introduced pancreatic juice as a valuable source of metabolic variables that could contribute to differential diagnosis. The correlation of metabolic markers with immune infiltration suggests that upfront evaluation of the metabolic profile of PDAC patients could foster the introduction of immunotherapeutic approaches for pancreatic cancer.

Cathepsin D Expression and Gemcitabine Resistance in Pancreatic Cancer

BACKGROUND

Cathepsin-D (CatD), owing to its dual role as a proteolytic enzyme and as a ligand, has been implicated in cancer progression. The role of CatD in pancreatic ductal adenocarcinoma is unknown.

METHODS

CatD expression quantified by immunohistochemistry of tumor-tissue microarrays of 403 resected pancreatic cancer patients from the ESPAC-Tplus trial, a translational study within the ESPAC (European Study Group for Pancreatic Cancer) trials, was dichotomously distributed to low and high H scores (cut off 22.35) for survival and multivariable analysis. The validation cohort (n = 69) was recruited based on the hazard ratio of CatD from ESPAC-Tplus. 5-fluorouracil-, and gemcitabine-resistant pancreatic cancer cell lines were employed for mechanistic experiments. All statistical tests were two-sided.

RESULTS

Median overall survival was 23.75 months and median overall survival for patients with high CatD expression was 21.09 (95% confidence interval [CI] = 17.31 to 24.80) months vs 27.20 (95% CI = 23.75 to 31.90) months for low CatD expression (χ2 LR, 1DF = 4.00; P = .04). Multivariable analysis revealed CatD expression as a predictive marker in gemcitabine-treated (z stat = 2.33; P = .02) but not in 5-fluorouracil-treated (z stat = 0.21; P = .82) patients. An independent validation cohort confirmed CatD as a negative predictive marker for survival (χ2 LR, 1DF = 6.80; P = .009) and as an independent predictive marker in gemcitabine-treated patients with a hazard ratio of 3.38 (95% CI = 1.36 to 8.38, P = .008). Overexpression of CatD was associated with a concomitant suppression of the acid sphingomyelinase, and silencing of CatD resulted in upregulation of acid sphingomyelinase with rescue of gemcitabine resistance.

CONCLUSIONS

Adjuvant gemcitabine is less effective in pancreatic ductal adenocarcinoma with high CatD expression, and thus CatD could serve as a marker for biomarker-driven therapy.

Machine Learning and Network Analyses Reveal Disease Subtypes of Pancreatic Cancer and their Molecular Characteristics

Given that the biological processes governing the oncogenesis of pancreatic cancers could present useful therapeutic targets, there is a pressing need to molecularly distinguish between different clinically relevant pancreatic cancer subtypes. To address this challenge, we used targeted proteomics and other molecular data compiled by The Cancer Genome Atlas to reveal that pancreatic tumours can be broadly segregated into two distinct subtypes. Besides being associated with substantially different clinical outcomes, tumours belonging to each of these subtypes also display notable differences in diverse signalling pathways and biological processes. At the proteome level, we show that tumours belonging to the less severe subtype are characterised by aberrant mTOR signalling, whereas those belonging to the more severe subtype are characterised by disruptions in SMAD and cell cycle-related processes. We use machine learning algorithms to define sets of proteins, mRNAs, miRNAs and DNA methylation patterns that could serve as biomarkers to accurately differentiate between the two pancreatic cancer subtypes. Lastly, we confirm the biological relevance of the identified biomarkers by showing that these can be used together with pattern-recognition algorithms to accurately infer the drug sensitivity of pancreatic cancer cell lines. Our study shows that integrative profiling of multiple data types enables a biological and clinical representation of pancreatic cancer that is comprehensive enough to provide a foundation for future therapeutic strategies.

Deciphering the Crosstalk Between Myeloid-Derived Suppressor Cells and Regulatory T Cells in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a fatal disease with rising incidence and a remarkable resistance to current therapies. The reasons for this therapeutic failure include the tumor's extensive infiltration by immunosuppressive cells such as myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs). By using light sheet fluorescent microscopy, we identified here direct interactions between these major immunoregulatory cells in PDAC. The in vivo depletion of MDSCs led to a significant reduction in Tregs in the pancreatic tumors. Through videomicroscopy and ex vivo functional assays we have shown that (i) MDSCs are able to induce Treg cells in a cell-cell dependent manner; (ii) Treg cells affect the survival and/or the proliferation of MDSCs. Furthermore, we have observed contacts between MDSCs and Treg cells at different stages of human cancer. Overall our findings suggest that interactions between MDSCs and Treg cells contribute to PDAC immunosuppressive environment.

Human equilibrative nucleoside transporter-1 expression is a predictor in patients with resected pancreatic cancer treated with adjuvant S-1 chemotherapy

The high expression of human equilibrative nucleoside transporter‐1 (hENT1) and the low expression of dihydropyrimidine dehydrogenase (DPD) are reported to predict a favorable prognosis in patients treated with gemcitabine (GEM) and 5‐fluorouracil (5FU) as the adjuvant setting, respectively. The expression of hENT1 and DPD were analyzed in patients registered in the JASPAC 01 trial, which showed a better survival of S‐1 over GEM as adjuvant chemotherapy after resection for pancreatic cancer, and their possible roles for predicting treatment outcomes and selecting a chemotherapeutic agent were investigated. Intensity of hENT1 and DPD expression was categorized into no, weak, moderate or strong by immunohistochemistry staining, and the patients were classified into high (strong/moderate) and low (no/weak) groups. Specimens were available for 326 of 377 (86.5%) patients. High expression of hENT1 and DPD was detected in 100 (30.7%) and 63 (19.3%) of 326 patients, respectively. In the S‐1 arm, the median overall survival (OS) with low hENT1, 58.0 months, was significantly better than that with high hENT1, 30.9 months (hazard ratio 1.75, P = 0.007). In contrast, there were no significant differences in OS between DPD low and high groups in the S‐1 arm and neither the expression levels of hENT1 nor DPD revealed a relationship with treatment outcomes in the GEM arm. The present study did not show that the DPD and hENT1 are useful biomarkers for choosing S‐1 or GEM as adjuvant chemotherapy. However, hENT1 expression is a significant prognostic factor for survival in the S‐1 arm.

Transcription factor NFAT5 contributes to the glycolytic phenotype rewiring and pancreatic cancer progression via transcription of PGK1

Hypoxia and the hypovascular tumor microenvironment are major hallmarks of pancreatic ductal adenocarcinoma (PDAC), in which glycolysis is of great importance to tumor survival and proliferation. There is little research regarding the role of Nuclear Factor of Activated T Cells 5 (NFAT5) in relation to carcinoma. Here, we explored the impact of NFAT5 on the biological behavior of PDAC and the underlying mechanism. We demonstrated that NFAT5 was highly expressed in PDAC and was related to poorer prognosis. Knockdown of NFAT5 lead to impaired proliferation of tumor cells caused by an aberrant Warburg effect. Mechanically, phosphoglycerate kinase 1 (PGK-1), which is the first enzyme generating ATP in glycolysis, was verified as a target gene of NFAT5. Over-expression of PGK1 compromised the aberrant oncological behavior caused by knockdown of NFAT5 both in vitro and in vivo. Clinical samples underwent positron emission tomography-computed tomography (PET-CT) examination and KrasG12D/+/Trp53R172H/+/Pdx1-Cre (KPC) mice were collected to support our conclusion.

HEATR1 deficiency promotes pancreatic cancer proliferation and gemcitabine resistance by up-regulating Nrf2 signaling

The human HEAT repeat-containing protein 1 (HEATR1), consisting of 2144 amino acids, is a member of the UTP10 family and contains one HEAT repeat at its C-terminal. HEATR1 has been reported to regulate cytotoxic T lymphocytes and rRNA synthesis, while its functions in tumors are poorly understood. Here, we found that HEATR1 competed with Keap1 for binding to p62/sequestosome 1 (SQSTM1), resulted in up-regulation of Keap1, which then inhibited Nrf2 signaling in pancreatic cancer cells. HEATR1 knockdown enhanced proliferation and gemcitabine resistance of pancreatic cancer cells. Moreover, HEATR1 deficiency significantly improved xenografts growth and led to gemcitabine resistance in pancreatic cancer cell-derived xenografts through up-regulating Nrf2 signaling. By analyzing tumor tissue samples from pancreatic cancer patients, we found that low expression of HEATR1 was closely correlated with poor prognosis and clinicopathological features. Collectively, we suggest that HEATR1 deficiency promotes proliferation and gemcitabine resistance of pancreatic cancer through up-regulating Nrf2 signaling, indicating that HEATR1 may be a promising therapeutic target for pancreatic cancer.

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HEATR1 inhibited Nrf2 signaling in pancreatic cancer cells.

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HEATR1 inhibited Nrf2 signaling through competing with Keap1 for p62 binding in pancreatic cancer cells.

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HEATR1 deficiency promoted pancreatic cancer proliferation and gemcitabine resistance by up-regulating Nrf2 signaling.

Tumour cell-derived debris and IgG synergistically promote metastasis of pancreatic cancer by inducing inflammation via tumour-associated macrophages

Background

The progression and metastasis of pancreatic ductal adenocarcinoma (PDAC) is highly dependent on the tumour microenvironment. Most tumour-associated macrophages (TAMs) are M2 phenotype macrophages, which normally show anti-inflammatory functions in numerous disorders. Previously, we found that alternatively activated macrophages showed pro-inflammatory characteristics upon stimulation with hepatoma cell-derived debris; however, the molecular mechanism was unclear.

Methods

In vitro and in vivo experiments were employed to investigate the molecular mechanism. Using pancreatic cancer cell lines, mouse models and human tissues, we obtained a general picture of tumour cell-derived debris promoting metastasis of pancreatic cancer by inducing inflammation via TAMs.

Results

We showed that M2 macrophage-derived inflammation also exists in PDAC. Debris from PDAC cells induced potent IL-1β release by M2 macrophages via TLR4/TRIF/NF-κB signalling, and this effect was further boosted by IgG that was also derived from PDAC cells. Increased IL-1β promoted epithelial–mesenchymal transition and consequent metastasis of PDAC cells. A selective COX-2 inhibitor, celecoxib, enhanced the anti-tumoural efficacy of gemcitabine.

Conclusions

These data revealed a pro-inflammatory mechanism in PDAC, which indicated that IL-1β and COX-2 could be therapeutic targets of an anti-inflammatory strategy to treat PDAC.

The microRNA-375 as a potentially promising biomarker to predict the prognosis of patients with head and neck or esophageal squamous cell carcinoma: a meta-analysis

BACKGROUND

The prognostic value of microRNA-375 (miR-375) expression in squamous cell carcinoma (SCC) had been reported in the previous studies; however, the results remain inconsistent. This study was performed to investigate the prognostic significance of miR-375 expression in SCC based on all eligible evidences.

METHODS

Relevant studies were identified by searching PubMed, Embace, Medline, Cochrane Library, and China Biology Medicine disk. Survival outcome including overall survival (OS) and other survival outcomes were used as the primary endpoint to evaluate the prognostic outcome of patients with SCC. All statistical analyses were performed in RevMan software version 5.3 and STATA software version 14.1. Furthermore, the quality of included studies was assessed by The Newcastle-Ottawa Scale.

RESULTS

In total, 13 studies, including 1340 patients, met the inclusion criteria for our meta-analysis. The pooled analysis results indicated that downregulation of miR-375 significantly predicted poor OS (HR 1.58, 95% CI 1.34-1.88, P < 0.001). Downregulated miR-375 was also correlated with the other survival outcomes. Subgroup analysis based on tumor type found that lower expression of miR-375 was significantly related with poor OS in patients with esophageal squamous cell carcinoma (ESCC) (HR 1.58, 95% CI 1.29-1.94, P < 0.001) and head and neck squamous cell carcinoma (HNSCC) (HR 1.59, 95% CI 1.16-2.18, P = 0.004).

CONCLUSIONS

This meta-analysis demonstrated that the downexpression of miR-375 was significantly correlated with poor OS in patients with SCCs and indicated the potential clinical use of miR-375 as a molecular biomarker, particularly in assessing prognosis for patients with ESCC and HNSCC.

Upregulated circular RNA circ_0030235 predicts unfavorable prognosis in pancreatic ductal adenocarcinoma and facilitates cell progression by sponging miR-1253 and miR-1294

Accumulating evidence indicated that dysregulated circular RNAs (circRNAs) could play pivotal roles in cancer biology. A recent study demonstrated that circ_0030235 expression is upregulated in human pancreatic ductal adenocarcinoma (PDAC) by high-throughput circRNA microarray. In the current work, we aimed to elucidate the clinical significance, prognostic value, functional roles and mechanism of circ_0030235 in PDAC. Quantitative real time-PCR was used to detect circ_0030235 expression in PDAC tissue specimens and cell lines. The clinical significance of circ_0030235 was evaluated by Fisher's exact test, Kaplan-Meier curves, and Cox regression analysis. Cell growth, apoptosis, and metastatic properties were then explored after circ_0030235 knockdown/overexpression. Dual luciferase reporter assay was applied to detect the mechanisms of circ_0030235. As a result, the data documented that circ_0030235 was upregulated in PDAC cell lines and cancerous tissues compared with HPDE and matched normal tissue specimens, respectively. Overexpression of circ_0030235 in tumor samples is related to higher tumor stage and positive lymph node invasion. Additionally, analyses documented that high expression of circ_0030235 was associated with poor prognosis for PDAC patients. Knockdown of circ_0030235 by siRNAs inhibited cell growth, migratory and invasive potential, and promoted cell apoptosis. On the contrary, overexpression of circ_0030235 caused the opposite effect. Mechanistically, circ_0030235 directly sponges miR-1253 and miR-1294 in PDAC cells. What's more, the oncogenic properties of circ_0030235 was partly dependent on its suppression on miR-1253 and miR-1294. Overall, the results showed that circ_0030235 might act as an effective therapeutic target and indicate dismal prognosis for PDAC.

B7-H5/CD28H is a co-stimulatory pathway and correlates with improved prognosis in pancreatic ductal adenocarcinoma

B7-H5 and its cognate receptor CD28H are T lymphocyte second signaling transduction molecules. Here we aimed to explore the function of this pathway in pancreatic cancer in vitro and in vivo, and evaluated the clinical significance in 136 patients with pancreatic ductal adenocarcinoma enrolled from January 2012 to February 2017 in our hospital. Surgical tumor specimens were collected for immunohistochemical staining to evaluate B7-H5 expression. Patients' baseline characteristics, including gender, age, tumor size, tumor location, tumor grading, clinical TNM staging, tumor infiltrating lymphocytes, CA19-9 and chemotherapy treatment, along with the subsequent follow-up data, were documented and analyzed. When co-cultured with T cells, pancreatic cancer PC cells with high B7-H5 expression induced a more potent immune reaction, indicated by elevated cytokine release and increased proliferation of T lymphocytes compared with cells exhibiting low B7-H5 expression. Xenograft pancreatic tumors derived from high B7-H5 expression PC cells exhibited attenuated growth compared to tumors from low B7-H5 expression cells after transfusion with T lymphocytes in immune-deficient mice. Of the 136 PDAC tumor tissues, 93 (68.38%) were strong and 43 (31.62%) were weak B7-H5 expression. Patients with strong B7-H5 expression had significantly longer overall survival than those with weak expression (median: 16.5 vs 11.5 months, P = .017). TNM staging, tumor location and subsequent chemotherapy were also prognostic factors in these patients. Collectively, B7-H5/CD28H is a co-stimulatory signal pathway, and expression of B7-H5 is associated with improved disease prognosis in patients with pancreatic cancer.