miRNA and Gene Expression in Pancreatic Ductal Adenocarcinoma

The growing field of liquid biopsy and its Snowball effect on reshaping cancer management

Liquid biopsy (LB) has emerged as a transformative tool in oncology, providing a minimally invasive approach for tumor detection, molecular characterization, and real-time treatment monitoring. By analyzing circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), extracellular vesicles (EVs), and microRNA (miRNA), LB enables comprehensive tumor profiling without the need for traditional tissue biopsies. Over the past decade, research in this field has expanded exponentially, leading to the integration of LB into clinical practice for specific cancer types, including lung and breast cancer. In 2024, the Journal of Liquid Biopsy (JLB) published innovative studies exploring the latest advancements in LB technologies, biomarkers, and their applications for cancer detection, minimal residual disease (MRD) monitoring, and therapy response assessment. This review synthesizes recent findings on the role of LB in cancer treatment and monitoring across different biomarkers, with a particular focus on newly published studies and their context within translational research. Additionally, it highlights emerging techniques such as fragmentomics, artificial intelligence, and multiomics, paving the way for more precise, personalized treatment decisions. Despite these advancements, challenges remain in standardizing methodologies, optimizing clinical validation, and integrating LB into routine oncological workflows. This mini-review highlights the evolving landscape of LB research and its potential to revolutionize cancer diagnosis, treatment monitoring, and therapeutic decision-making, ushering in a new era of precision oncology.

Self-emulsifying Nano-PND oral delivery systems of PND1186: In silico modeling for bioavailability estimation

Focal adhesion kinase (FAK) inhibitors have proven to aid the therapeutic potential of anti-cancer agents. PND1186 (PND) is a FAK inhibitor disrupting the oncogenic processes such as cell survival, proliferation, adhesion, migration and angiogenesis, as well as remodeling of tumor microenvironment. However, the pharmacological potential of PND is limited by its poor solubility and bioavailability due to rapid precipitation of weakly basic PND in the intestinal milieu. As a solution, we have developed a self-nanoemulsifying PND oral delivery system (NanoPODS) for rapid dissolution of PND while Soluplus containing system (NanoPODS-S) was prepared to prevent the precipitation of PND. Optimized NanoPODS-S depicted a particle size of 107.0 ± 3.6 nm, PDI of 0.223 ± 0.016, and a surface potential of -4.2 ± 0.007 mV, along with > 70% PND released at pH 6.8. In silico pharmacokinetics predicted 99% oral bioavailability for NanoPODS-S. This study evaluates the efficacy of NanoPODS and NanoPODS-S for improved oral bioavailability with better cytotoxicity efficacy on Pancreatic Ductal Adenocarcinoma (PDAC) cell lines. NanoPODS-S is the first of its kind, self-nanoemulsifying system containing a polymeric precipitation inhibitor mimicking a "spring-parachute effect". It will be a novel platform technology for rapid and enhanced dissolution of poorly soluble molecules.

Identification of key hub genes in pancreatic ductal adenocarcinoma: an integrative bioinformatics study

Pancreatic Ductal Adenocarcinoma (PDAC) poses a significant health threat characterized by poor clinical outcomes, largely attributable to late detection, chemotherapy resistance, and the absence of tailored therapies. Despite progress in surgical, radiation, and chemotherapy treatments, 80% of PDAC patients do not benefit optimally from systemic therapy, often due to asymptomatic presentation or disease regression upon diagnosis. The disease's progression is influenced by complex interactions involving immunological, genetic, and environmental factors, among others. However, the precise molecular mechanisms underlying PDAC remain incompletely understood. A major challenge in elucidating PDAC's origins lies in deciphering the genetic variations governing its network. PDAC exhibits heterogeneity, manifesting diverse genetic compositions, cellular attributes, and behaviors across patients and within tumors. This diversity complicates diagnosis, treatment strategies, and prognostication. Identification of "Differentially Expressed Genes" (DEGs) between PDAC and healthy controls is vital for addressing these challenges. These DEGs serve as the foundation for constructing the PDAC protein interaction network, with their network properties being assessed for further insights. Our analysis revealed five key hub genes (KHGs): EGF, SRC, SDC1, ICAM1 and CEACAM5. The KHGs were predominantly enriched in pathways such as: ErbB signaling pathway, Rap1 signaling pathway, etc. Acknowledging the therapeutic promise and biomarker importance of PDAC KHGs, we have also pinpointed approved medications for the identified key genes. Nevertheless, it is crucial to conduct experimental validation on KHGs to confirm their effectiveness within the PDAC context. Overall, this study identified potential key hub genes implicated in the progression of PDAC, offering significant guidance for personalized clinical decision-making and molecular-targeted therapy for PDAC patients.

miRNA profile in pancreatic neuroendocrine tumors: Preliminary results

OBJECTIVE

Our understanding of the pathophysiology of pancreatic neuroendocrine tumors (PanNETs) remains incomplete, largely due to their historically underestimated incidence and the perception of these tumors as rare and slow-growing cancers. Additionally, conventional reliance on histological examination alone is gradually being supplemented by the exploration and introduction of molecular biomarkers, such as microRNAs (miRNAs). As miRNAs modulate the expression of multiple genes and pathways involved in the tumorigenesis of PanNETs, these biomarkers hold considerable promise for diagnosis and prognosis applications. In this study, we aimed to identify miRNAs as tissue markers associated with the diagnosis of PanNETs.

METHODS

We conducted a case-control study including: 7 PanNETs and 19 nontumoral pancreatic tissues obtained from Romanian patients. The samples underwent miRNA profiling via quantitative RT-PCR to assess the expression of 84 miRNAs. Our results were compared with those obtained by reanalyzing a public dataset. Furthermore, we structured our miRNA expression data according to their targeted mRNAs and their roles in signaling pathways.

RESULTS

Fourteen miRNAs (miR-1, miR-133a-3p, miR-210-3p, miR-7-5p, miR-10a-5p, miR-92b-3p, miR-132-3p, miR-221-3p, miR-29b-3p, miR-107, miR-103a-3p, let-7b-5p, miR-148a-3p, and miR-202-3p) were identified as differentially expressed by comparing PanNETs with pancreatic nontumoral tissues, with six miRNAs (miR-7-5p, miR-92b-3p, miR-29b-3p, miR-107, miR-103a-3p, and miR-148a-3p) also found in the public dataset analyzed. Bioinformatic analysis revealed that the 14 identified miRNAs target 17 genes. Reanalyzing two public gene expression datasets, five of these genes have been found differentially expressed in PanNET compared to controls.

CONCLUSIONS

Our preliminary results, albeit limited by a small sample size, highlighted a specific miRNA expression pattern able to distinguish tumoral from normal pancreatic tissue. The diagnostic performance of these miRNAs, matching with circulating miRNAs and validated in more homogeneous and large cohorts, could represent a starting point for improving the diagnostic accuracy of PanNETs.

Significant association of miRNA 34a with BRCA1 expression in pancreatic ductal adenocarcinoma: an insight on miRNA regulatory pathways in the Pakistani population

BACKGROUND

Pancreatic Ductal Adenocarcinoma (PDAC) is among the most aggressive cancers, characterized by high mortality rates. Studies on various cancers across the globe indicate that regulatory miRNAs play a vital role in cellular signaling. However, the expression and interactions of these miRNAs in the Pakistani patients with PDAC is yet to be explored. Here, we aim to investigate a panel of four regulatory miRNAs (miRNA 34a, 30b, 142 and 137) in PDAC and their interaction with selected target proteins in the signaling pathway (KRAS, p53, BRCA1, APC).

METHODS

We conducted a study on 109 PDAC patients to analyze the selected miRNAs and protein targets. Formalin Fixed Paraffin Embedded (FFPE) tumor samples were obtained from the hospital's department of histopathology. After confirmation of diagnosis and appropriate tumor content, tissues were processed for RNA extraction. Based on the acceptable quality and quantity of RNA, 43 samples were proceeded for qRT-PCR. Relative expression of the miRNAs was determined through 2-[ΔΔCt] method. Further, FFPE tumor blocks were used to perform tissue sectioning followed by immunohistochemistry experiments. Stained slides were scored independently by two pathologists according to set criteria.

RESULTS

Expression profiles revealed that miRNA 34a, 30b, and 142 showed high expression in approximately 69-70% of cases, while miRNA 137 had a lower high expression frequency (53.4%). Among protein biomarkers, KRAS, BRCA1, and APC were predominantly expressed, with high expression levels observed in 79.1%, 69.8%, and 51.2% of cases, respectively, whereas p53 showed positive expression in only 34.9% of cases. Statistical analysis showed that expression of miRNA 34a was significantly associated with the expression of BRCA1 (p = 0.034). No significant associations were observed for KRAS, p53, or APC with the selected miRNAs. Moreover, the expression of miRNA 34a independently showed significant association with miRNA 30b (p = 0.000) and miRNA 137 (p = 0.001). None of the miRNA showed an association with the overall survival, patient demographics or the clinicopathological characteristics.

CONCLUSION

Our study highlights a potential bi-directional regulatory relationship between BRCA1 and miRNA 34a, suggesting that miRNA 34a may both respond to and influence BRCA1 activity within cellular signaling pathways. This complex interaction points to a layered regulatory network that could play a crucial role in tumor suppression in PDAC, underscoring the therapeutic potential of targeting this miRNA-protein crosstalk.

Plasma miR-379 can predict treatment response to FOLFIRINOX and gemcitabine-nab-paclitaxel in advanced pancreatic cancer

Background

Novel biomarkers, such as plasma microRNAs (miRs), are needed to help guide clinical decision-making for the type of chemotherapy to use in patients with advanced pancreatic ductal adenocarcinoma (PDAC). This study assessed the ability of plasma miRs to predict optimal treatment response from FOLFIRINOX or gemcitabine-nab-paclitaxel in these patients.

Methods

Next-generation sequencing (NGS) was performed for biomarker discovery in pre-treatment plasma samples from advanced PDAC patients subsequently treated with FOLFIRINOX (n = 12) or gemcitabine-nab-paclitaxel (n = 12). Selected candidate biomarkers were validated in 40 patients with advanced PDAC using RT-qPCR. Cox regression was then used to assess the predictive value of plasma miRs for either FOLFIRINOX or gemcitabine-nab-paclitaxel.

Results

In the validation cohort, high plasma miR-379 expression was strongly predictive of treatment response (Pinteraction = 0.0004). Overall survival (OS) was significantly better with FOLFIRINOX vs. gemcitabine-nab-paclitaxel in those patients with lower plasma miR-379 expression (hazard ratio, 0.32 [95% confidence interval, 0.08 to 0.98]; P = 0.046). However, gemcitabine-nab-paclitaxel was associated with superior OS in patients with higher plasma miR-379 (hazard ratio, 0.28 [0.10 to 0.86]; P = 0.027). In contrast, miR-127, miR-155, and miR-200 showed no predictive value for treatment response for either chemotherapy regimen (P interaction = 0.12, P interaction = 0.83 and P interaction = 0.12, respectively).

Conclusions

Plasma miR-379 appears clinically useful as a predictive biomarker to identify which patients with advanced PDAC benefit most from treatment with FOLFIRINOX or gemcitabine-nab-paclitaxel. Further validation in larger studies and clinical trials is now warranted.

Using microRNAs Networks to Understand Pancreatic Cancer-A Literature Review

Pancreatic cancer is a severe disease, challenging to diagnose and treat, and thereby characterized by a poor prognosis and a high mortality rate. Pancreatic ductal adenocarcinoma (PDAC) represents approximately 90% of pancreatic cancer cases, while other cases include neuroendocrine carcinoma. Despite the growing knowledge of the pathophysiology of this cancer, the mortality rate caused by it has not been effectively reduced. Recently, microRNAs have aroused great interest among scientists and clinicians, as they are negative regulators of gene expression, which participate in many processes, including those related to the development of pancreatic cancer. The aim of this review is to show how microRNAs (miRNAs) affect key signaling pathways and related cellular processes in pancreatic cancer development, progression, diagnosis and treatment. We included the results of in vitro studies, animal model of pancreatic cancer and those performed on blood, saliva and tumor tissue isolated from patients suffering from PDAC. Our investigation identified numerous dysregulated miRNAs involved in KRAS, JAK/STAT, PI3/AKT, Wnt/β-catenin and TGF-β signaling pathways participating in cell cycle control, proliferation, differentiation, apoptosis and metastasis. Moreover, some miRNAs (miRNA-23a, miRNA-24, miRNA-29c, miRNA-216a) seem to be engaged in a crosstalk between signaling pathways. Evidence concerning the utility of microRNAs in the diagnosis and therapy of this cancer is poor. Therefore, despite growing knowledge of the involvement of miRNAs in several processes associated with pancreatic cancer, we are beginning to recognize and understand their role and usefulness in clinical practice.

Dysregulation of a Subset of Circulating and Vesicle-Associated miRNA in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive neoplasia, characterized by early metastasis, low diagnostic rates at early stages, resistance to drugs, and poor prognosis. There is an urgent need to better characterize this disease in order to identify efficient diagnostic/prognostic biomarkers. Since microRNAs (miRNAs) contribute to oncogenesis and metastasis formation in PDAC, they are considered potential candidates for fulfilling this task. In this work, the levels of two miRNA subsets (involved in chemoresistance or with oncogenic/tumor suppressing functions) were investigated in a panel of PDAC cell lines and liquid biopsies of a small cohort of patients. We used RT-qPCR and droplet digital PCR (ddPCR) to measure the amounts of cellular- and vesicle-associated, and circulating miRNAs. We found that both PDAC cell lines, also after gemcitabine treatment, and patients showed low amounts of cellular-and vesicle-associated miR-155-5p, compared to controls. Interestingly, we did not find any differences when we analyzed circulating miR-155-5p. Furthermore, vesicle-related miR-27a-3p increased in cancer patients compared to the controls, while circulating let-7a-5p, miR-221-3p, miR-23b-3p and miR-193a-3p presented as dysregulated in patients compared to healthy individuals. Our results highlight the potential clinical significance of these analyzed miRNAs as non-invasive diagnostic molecular tools to characterize PDAC.

MicroRNAs in Pancreatic Cancer: Advances in Biomarker Discovery and Therapeutic Implications

Pancreatic cancer remains a formidable malignancy characterized by high mortality rates, primarily attributable to late-stage diagnosis and a dearth of effective therapeutic interventions. The identification of reliable biomarkers holds paramount importance in enhancing early detection, prognostic evaluation, and targeted treatment modalities. Small non-coding RNAs, particularly microRNAs, have emerged as promising candidates for pancreatic cancer biomarkers in recent years. In this review, we delve into the evolving role of cellular and circulating miRNAs, including exosomal miRNAs, in the diagnosis, prognosis, and therapeutic targeting of pancreatic cancer. Drawing upon the latest research advancements in omics data-driven biomarker discovery, we also perform a case study using public datasets and address commonly identified research discrepancies, challenges, and limitations. Lastly, we discuss analytical approaches that integrate multimodal analyses incorporating clinical and molecular features, presenting new insights into identifying robust miRNA-centric biomarkers.

A Current Synopsis of the Emerging Role of Extracellular Vesicles and Micro-RNAs in Pancreatic Cancer: A Forward-Looking Plan for Diagnosis and Treatment

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies worldwide, while it persists as the fourth most prevalent cause of cancer-related death in the United States of America. Although there are several novel therapeutic strategies for the approach of this intensely aggressive tumor, it remains a clinical challenge, as it is hard to identify in early stages, due to its asymptomatic course. A diagnosis is usually established when the disease is already in its late stages, while its chemoresistance constitutes an obstacle to the optimal management of this malignancy. The discovery of novel diagnostic and therapeutic tools is considered a necessity for this tumor, due to its low survival rates and treatment failures. One of the most extensively investigated potential diagnostic and therapeutic modalities is extracellular vesicles (EVs). These vesicles constitute nanosized double-lipid membraned particles that are characterized by a high heterogeneity that emerges from their distinct biogenesis route, their multi-variable sizes, and the particular cargoes that are embedded into these particles. Their pivotal role in cell-to-cell communication via their cargo and their implication in the pathophysiology of several diseases, including pancreatic cancer, opens new horizons in the management of this malignancy. Meanwhile, the interplay between pancreatic carcinogenesis and short non-coding RNA molecules (micro-RNAs or miRs) is in the spotlight of current studies, as they can have either a role as tumor suppressors or promoters. The deregulation of both of the aforementioned molecules leads to several aberrations in the function of pancreatic cells, leading to carcinogenesis. In this review, we will explore the role of extracellular vesicles and miRNAs in pancreatic cancer, as well as their potent utilization as diagnostic and therapeutic tools.

Genomic insights and prognostic significance of novel biomarkers in pancreatic ductal adenocarcinoma: A comprehensive analysis

Pancreatic ductal adenocarcinoma (PDAC) is a highly prevalent digestive system malignancy, with a significant impact on public health, especially in the elderly population. The advent of the Human Genome Project has opened new avenues for precision medicine, allowing researchers to explore genetic markers and molecular targets for cancer diagnosis and treatment. Despite significant advances in genomic research, early diagnosis of pancreatic cancer remains elusive due to the lack of highly sensitive and specific markers. Therefore, there is a need for in-depth research to identify more precise and reliable diagnostic markers for pancreatic cancer. In this study, we utilized a combination of public databases from different sources to meticulously screen genes associated with prognosis in pancreatic cancer. We used gene differential analysis, univariate cox regression analysis, least absolute selection and shrinkage operator (LASSO) regression, and multivariate cox regression analysis to identify genes associated with prognosis. Subsequently, we constructed a scoring system, validated its validity using survival analysis and ROC analysis, and further confirmed its reliability by nomogram and decision curve analysis (DCA). We evaluated the diagnostic value of this scoring system for pancreatic cancer prognosis and validated the function of the genes using single cell data analysis. Our analysis identifies six genes, including GABRA3, IL20RB, CDK1, GPR87, TTYH3, and KCNA2, that were strongly associated with PDAC prognosis. Clinical prognostic models based on these genes showed strong predictive power not only in the training set but also in external datasets. Functional enrichment analysis revealed significant differences between high- and low-risk groups mainly in immune-related functions. Additionally, we explored the potential of the risk score as a marker for immunotherapy response and identified key factors within the tumor microenvironment. The single-cell RNA sequencing analysis further enriched our understanding of cell clusters and six hub genes expressions. This comprehensive investigation provides valuable insights into pancreatic PDAC and its intricate immune landscape. The identified genes and their functional significance underscore the importance of continued research into improving diagnosis and treatment strategies for PDAC.

Functional and Potential Therapeutic Implication of MicroRNAs in Pancreatic Cancer

The alarmingly low five-year survival rate for pancreatic cancer presents a global health challenge, contributing to about 7% of all cancer-related deaths. Late-stage diagnosis and high heterogeneity are the biggest hurdles in treating pancreatic cancer. Thus, there is a pressing need to discover novel biomarkers that could help in early detection as well as improve therapeutic strategies. MicroRNAs (miRNAs), a class of short non-coding RNA, have emerged as promising candidates with regard to both diagnostics and therapeutics. Dysregulated miRNAs play pivotal roles in accelerating tumor growth and metastasis, orchestrating tumor microenvironment, and conferring chemoresistance in pancreatic cancer. The differential expression profiles of miRNAs in pancreatic cancer could be utilized to explore novel therapeutic strategies. In this review, we also covered studies on recent advancements in various miRNA-based therapeutics such as restoring miRNAs with a tumor-suppressive function, suppressing miRNA with an oncogenic function, and combination with chemotherapeutic drugs. Despite several challenges in terms of specificity and targeted delivery, miRNA-based therapies hold the potential to revolutionize the treatment of pancreatic cancer by simultaneously targeting multiple signaling pathways.

Investigating the regulatory role of miRNAs as silent conductors in the management of pathogenesis and therapeutic resistance of pancreatic cancer

Pancreatic cancer (PC) has the greatest mortality rate of all the main malignancies. Its advanced stage and poor prognosis place it at the bottom of all cancer sites. Hence, emerging biomarkers can enable precision medicine where PC therapy is tailored to each patient. This highlights the need for new, highly sensitive and specific biomarkers for early PC diagnosis. Prognostic indicators are also required to stratify PC patients. To avoid ineffective treatment, adverse events, and expenses, biomarkers are also required for patient monitoring and identifying responders to treatment. There is substantial evidence that microRNAs (miRs, miRNAs) play a critical role in regulating mRNA and, as a consequence, protein expression in normal and malignant tissues. Deregulated miRNA profiling in PC can help with diagnosis, treatment planning, and prognosis. Furthermore, knowledge of the primary effector genes and downstream pathways in PC can help pinpoint potential miRNAs for use in treatment. Different miRNA expression profiles may serve as diagnostic, prognostic markers, and therapeutic targets across the spectrum of malignant pancreatic illness. Dysregulation of miRNAs has been linked to the malignant pathophysiology of PC through affecting many cellular functions such as increasing invasive and proliferative prospect, supporting angiogenesis, cell cycle aberrance, apoptosis elusion, metastasis promotion, and low sensitivity to particular treatments. Accordingly, in the current review, we summarize the recent advances in the roles of oncogenic and tumor suppressor (TS) miRNAs in PC and discuss their potential as worthy diagnostic and prognostic biomarkers for PC, as well as their significance in PC pathogenesis and anticancer drug resistance.

Targeting miRNA and using miRNA as potential therapeutic options to bypass resistance in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive disease with poor prognosis due to early metastasis, low diagnostic rates at early stages, and resistance to current therapeutic regimens. Despite numerous studies and clinical trials, the mortality rate for PDAC has shown limited improvement. Therefore, there is a pressing need to attain. a more comprehensive molecular characterization to identify biomarkers enabling early detection and evaluation of treatment response. MicroRNA (miRNAs) are critical regulators of gene expression on the post-transcriptional level, and seem particularly interesting as biomarkers due to their relative stability, and the ability to detect them in fixed tissue specimens and biofluids. Deregulation of miRNAs is common and affects several hallmarks of cancer and contribute to the oncogenesis and metastasis of PDAC. Unique combinations of upregulated oncogenic miRNAs (oncomiRs) and downregulated tumor suppressor miRNAs (TsmiRs), promote metastasis, characterize the tumor and interfere with chemosensitivity of PDAC cells. Here, we review several oncomiRs and TsmiRs involved in chemoresistance to gemcitabine and FOLFIRINOX in PDAC and highlighted successful/effective miRNA-based therapy approaches in vivo. Integrating miRNAs in PDAC treatment represents a promising therapeutic avenue that can be used as guidance for personalized medicine for PDAC patients.

NamiRNA-enhancer network of miR-492 activates the NR2C1-TGF-β/Smad3 pathway to promote epithelial-mesenchymal transition of pancreatic cancer

Pancreatic cancer (PaCa) is one of the most fatal malignancies of the digestive system, and most patients are diagnosed at advanced stages due to the lack of specific and effective tumor-related biomarkers for the early detection of PaCa. miR-492 has been found to be upregulated in PaCa tumor tissue and may serve as a potential therapeutic target. However, the molecular mechanisms by which miR-492 promotes PaCa tumor growth and progression are unclear. In this study, we first found that miR-492 in enhancer loci activated neighboring genes (NR2C1/NDUFA12/TMCC3) and promoted PaCa cell proliferation, migration, and invasion in vitro. We also observed that miR-492-activating genes significantly enriched the TGF-β/Smad3 signaling pathway in PaCa to promote epithelial-mesenchymal transition (EMT) during tumorigenesis and development. Using CRISPR-Cas9 and ChIP assays, we further observed that miR-492 acted as an enhancer trigger, and that antagomiR-492 repressed PaCa tumorigenesis in vivo, decreased the expression levels of serum TGF-β, and suppressed the EMT process by downregulating the expression of NR2C1. Our results demonstrate that miR-492, as an enhancer trigger, facilitates PaCa progression via the NR2C1-TGF-β/Smad3 pathway.

Gene Expression Comparison between Alcohol-Exposed versus Not Exposed Pancreatic Ductal Adenocarcinoma Patients Reveals a Peculiar TGFβ-Related Phenotype: An Exploratory Analysis

Background: Over the past few decades, there has been much debate and research into the link between alcohol consumption and the development and progression of pancreatic ductal adenocarcinoma (PDAC). Objectives: To contribute to the ongoing discussion and gain further insights into this topic, our study analysed the gene expression differences in PDAC patients based on their alcohol consumption history. Methods: To this end, we interrogated a large publicly available dataset. We next validated our findings in vitro. Results: Our findings revealed that patients with a history of alcohol consumption showed significant enrichment in the TGFβ-pathway: a signaling pathway implicated in cancer development and tumor progression. Specifically, our bioinformatic dissection of gene expression differences in 171 patients with PDAC showed that those who had consumed alcohol had higher levels of TGFβ-related genes. Moreover, we validated the role of the TGFβ pathway as one of the molecular drivers in producing massive stroma, a hallmark feature of PDAC, in patients with a history of alcohol consumption. This suggests that inhibition of the TGFβ pathway could serve as a novel therapeutic target for PDAC patients with a history of alcohol consumption and lead to increased sensitivity to chemotherapy. Our study provides valuable insights into the molecular mechanisms underlying the link between alcohol consumption and PDAC progression. Conclusions: Our findings highlight the potential significance of the TGFβ pathway as a therapeutic target. The development of TGFβ-inhibitors may pave the way for developing more effective treatment strategies for PDAC patients with a history of alcohol consumption.

Amplification-Free, High-Throughput Nanoplasmonic Quantification of Circulating MicroRNAs in Unprocessed Plasma Microsamples for Earlier Pancreatic Cancer Detection

Pancreatic ductal adenocarcinoma (PDAC) is a deadly malignancy that is often detected at an advanced stage. Earlier diagnosis of PDAC is key to reducing mortality. Circulating biomarkers such as microRNAs are gaining interest, but existing technologies require large sample volumes, amplification steps, extensive biofluid processing, lack sensitivity, and are low-throughput. Here, we present an advanced nanoplasmonic sensor for the highly sensitive, amplification-free detection and quantification of microRNAs (microRNA-10b, microRNA-let7a) from unprocessed plasma microsamples. The sensor construct utilizes uniquely designed -ssDNA receptors attached to gold triangular nanoprisms, which display unique localized surface plasmon resonance (LSPR) properties, in a multiwell plate format. The formation of -ssDNA/microRNA duplex controls the nanostructure-biomolecule interfacial electronic interactions to promote the charge transfer/exciton delocalization processes and enhance the LSPR responses to achieve attomolar (10-18 M) limit of detection (LOD) in human plasma. This improve LOD allows the fabrication of a high-throughput assay in a 384-well plate format. The performance of nanoplasmonic sensors for microRNA detection was further assessed by comparing with the qRT-PCR assay of 15 PDAC patient plasma samples that shows a positive correlation between these two assays with the Pearson correlation coefficient value >0.86. Evaluation of >170 clinical samples reveals that oncogenic microRNA-10b and tumor suppressor microRNA-let7a levels can individually differentiate PDAC from chronic pancreatitis and normal controls with >94% sensitivity and >94% specificity at a 95% confidence interval (CI). Furthermore, combining both oncogenic and tumor suppressor microRNA levels significantly improves differentiation of PDAC stages I and II versus III and IV with >91% and 87% sensitivity and specificity, respectively, in comparison to the sensitivity and specificity values for individual microRNAs. Moreover, we show that the level of microRNAs varies substantially in pre- and post-surgery PDAC patients (n = 75). Taken together, this ultrasensitive nanoplasmonic sensor with excellent sensitivity and specificity is capable of assaying multiple biomarkers simultaneously and may facilitate early detection of PDAC to improve patient care.

The key role of microRNA-766 in the cancer development

Cancer is caused by defects in coding and non-coding RNAs. In addition, duplicated biological pathways diminish the efficacy of mono target cancer drugs. MicroRNAs (miRNAs) are short, endogenous, non-coding RNAs that regulate many target genes and play a crucial role in physiological processes such as cell division, differentiation, cell cycle, proliferation, and apoptosis, which are frequently disrupted in diseases such as cancer. MiR-766, one of the most adaptable and highly conserved microRNAs, is notably overexpressed in several diseases, including malignant tumors. Variations in miR-766 expression are linked to various pathological and physiological processes. Additionally, miR-766 promotes therapeutic resistance pathways in various types of tumors. Here, we present and discuss evidence implicating miR-766 in the development of cancer and treatment resistance. In addition, we discuss the potential applications of miR-766 as a therapeutic cancer target, diagnostic biomarker, and prognostic indicator. This may shed light on the development of novel therapeutic strategies for cancer therapy.

Review of the endocrine organ-like tumor hypothesis of cancer cachexia in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal types of solid tumors, associated with a high prevalence of cachexia (~80%). PDAC-derived cachexia (PDAC-CC) is a systemic disease involving the complex interplay between the tumor and multiple organs. The endocrine organ-like tumor (EOLT) hypothesis may explain the systemic crosstalk underlying the deleterious homeostatic shifts that occur in PDAC-CC. Several studies have reported a markedly heterogeneous collection of cachectic mediators, signaling mechanisms, and metabolic pathways, including exocrine pancreatic insufficiency, hormonal disturbance, pro-inflammatory cytokine storm, digestive and tumor-derived factors, and PDAC progression. The complexities of PDAC-CC necessitate a careful review of recent literature summarizing cachectic mediators, corresponding metabolic functions, and the collateral impacts on wasting organs. The EOLT hypothesis suggests that metabolites, genetic instability, and epigenetic changes (microRNAs) are involved in cachexia development. Both tumors and host tissues can secrete multiple cachectic factors (beyond only inflammatory mediators). Some regulatory molecules, metabolites, and microRNAs are tissue-specific, resulting in insufficient energy production to support tumor/cachexia development. Due to these complexities, changes in a single factor can trigger bi-directional feedback circuits that exacerbate PDAC and result in the development of irreversible cachexia. We provide an integrated review based on 267 papers and 20 clinical trials from PubMed and ClinicalTrials.gov database proposed under the EOLT hypothesis that may provide a fundamental understanding of cachexia development and response to current treatments.

An immune-related microRNA signature prognostic model for pancreatic carcinoma and association with immune microenvironment

To establish a prognostic model based on immune-related microRNA (miRNA) for pancreatic carcinoma. Weighted correlation network analysis (WGCNA) was performed using the "WGCNA" package to find the key module genes involved in pancreatic carcinoma. Spearman correlation analysis was conducted to screen immune-related miRNAs. Uni- and multi-variate COX regression analyses were carried out to identify miRNAs prognostic for overall survival (OS) of pancreatic carcinoma, which were then combined to generate a prognostic model. Kaplan–Meier survival analysis, receiver operating characteristic (ROC) analysis, distribution plot of survival status in patients and regression analysis were collectively performed to study the accuracy of the model in prognosis. Target genes of the miRNAs in the model were intersected with the key module genes, and a miRNA–mRNA network was generated and visualized by Cytoscape3.8.0. TIMER analysis was conducted to study the abundance of immune infiltrates in tumor microenvironment of pancreatic carcinoma. Expression levels of immune checkpoint genes in subgroups stratified by the model were compared by Wilcoxon test. Gene Set Enrichment Analysis (GSEA) was performed to analyze the enriched signaling pathways between subgroups. Differential analysis revealed 1826 genes differentially up-regulated in pancreatic carcinoma and 1276 genes differentially down-regulated. A total of 700 immune-related miRNAs were obtained, of which 7 miRNAs were significantly associated with OS of patients and used to establish a prognostic model with accurate predictive performance. There were 99 mRNAs overlapped from the 318 target genes of the 7 miRNAs and the key modules genes analyzed by WGCNA. Patient samples were categorized as high or low risk according to the prognostic model, which were significantly associated with dendritic cell infiltration and expression of immune checkpoint genes (TNFSF9, TNFRSF9, KIR3DL1, HAVCR2, CD276 and CD80). GSEA showed remarkably enriched signaling pathways in the two subgroups. This study identified an immune-related 7-miRNA based prognostic model for pancreatic carcinoma, which could be used as a reliable tool for prognosis.

Oncogenomic Changes in Pancreatic Cancer and Their Detection in Stool

Pancreatic cancer (PC) is an aggressive malignancy with a dismal prognosis. To improve patient survival, the development of screening methods for early diagnosis is pivotal. Oncogenomic alterations present in tumor tissue are a suitable target for non-invasive screening efforts, as they can be detected in tumor-derived cells, cell-free nucleic acids, and extracellular vesicles, which are present in several body fluids. Since stool is an easily accessible source, which enables convenient and cost-effective sampling, it could be utilized for the screening of these traces. Herein, we explore the various oncogenomic changes that have been detected in PC tissue, such as chromosomal aberrations, mutations in driver genes, epigenetic alterations, and differentially expressed non-coding RNA. In addition, we briefly look into the role of altered gut microbiota in PC and their possible associations with oncogenomic changes. We also review the findings of genomic alterations in stool of PC patients, and the potentials and challenges of their future use for the development of stool screening tools, including the possible combination of genomic and microbiota markers.

Senescence-Associated miRNAs and Their Role in Pancreatic Cancer

Replicative senescence is irreversible cell proliferation arrest for somatic cells which can be circumvented in cancers. Cellular senescence is a process, which may play two opposite roles. On the one hand, this is a natural protection of somatic cells against unlimited proliferation and malignant transformation. On the other hand, cellular secretion caused by senescence can stimulate inflammation and proliferation of adjacent cells that may promote malignancy. The main genes controlling the senescence pathways are also well known as tumor suppressors. Almost 140 genes regulate both cellular senescence and cancer pathways. About two thirds of these genes (64%) are regulated by microRNAs. Senescence-associated miRNAs can stimulate cancer progression or act as tumor suppressors. Here we review the role playing by senescence-associated miRNAs in development, diagnostics and treatment of pancreatic cancer.

Circulating Nucleic Acids as Novel Biomarkers for Pancreatic Ductal Adenocarcinoma

Despite considerable advancements in the clinical management of PDAC it remains a significant cause of mortality. PDAC is often diagnosed at advanced stages due to vague symptoms associated with early-stage disease and a lack of reliable diagnostic biomarkers. Late diagnosis results in a high proportion of cases being ineligible for surgical resection, the only potentially curative therapy for PDAC. Furthermore, a lack of prognostic biomarkers impedes clinician's ability to properly assess the efficacy of therapeutic interventions. Advances in our ability to detect circulating nucleic acids allows for the advent of novel biomarkers for PDAC. Tumor derived circulating and exosomal nucleic acids allow for the detection of PDAC-specific mutations through a non-invasive blood sample. Such biomarkers could expand upon the currently limited repertoire of tests available. This review outlines recent developments in the use of molecular techniques for the detection of these nucleic acids and their potential roles, alongside current techniques, in the diagnosis, prognosis and therapeutic governance of PDAC.

Application of Proteomics in Pancreatic Ductal Adenocarcinoma Biomarker Investigations: A Review

Pancreatic ductal adenocarcinoma (PDAC), a highly aggressive malignancy with a poor prognosis is usually detected at the advanced stage of the disease. The only US Food and Drug Administration-approved biomarker that is available for PDAC, CA 19-9, is most useful in monitoring treatment response among PDAC patients rather than for early detection. Moreover, when CA 19-9 is solely used for diagnostic purposes, it has only a recorded sensitivity of 79% and specificity of 82% in symptomatic individuals. Therefore, there is an urgent need to identify reliable biomarkers for diagnosis (specifically for the early diagnosis), ascertain prognosis as well as to monitor treatment response and tumour recurrence of PDAC. In recent years, proteomic technologies are growing exponentially at an accelerated rate for a wide range of applications in cancer research. In this review, we discussed the current status of biomarker research for PDAC using various proteomic technologies. This review will explore the potential perspective for understanding and identifying the unique alterations in protein expressions that could prove beneficial in discovering new robust biomarkers to detect PDAC at an early stage, ascertain prognosis of patients with the disease in addition to monitoring treatment response and tumour recurrence of patients.

microRNA-21 Regulates Stemness in Pancreatic Ductal Adenocarcinoma Cells

Pancreatic ductal adenocarcinoma (PDAC) is the most common and aggressive type of pancreatic cancer (PCa) with a low survival rate. microRNAs (miRs) are endogenous, non-coding RNAs that moderate numerous biological processes. miRs have been associated with the chemoresistance and metastasis of PDAC and the presence of a subpopulation of highly plastic "stem"-like cells within the tumor, known as cancer stem cells (CSCs). In this study, we investigated the role of miR-21, which is highly expressed in Panc-1 and MiaPaCa-2 PDAC cells in association with CSCs. Following miR-21 knockouts (KO) from both MiaPaCa-2 and Panc-1 cell lines, reversed expressions of epithelial-mesenchymal transition (EMT) and CSCs markers were observed. The expression patterns of key CSC markers, including CD44, CD133, CX-C chemokine receptor type 4 (CXCR4), and aldehyde dehydrogenase-1 (ALDH1), were changed depending on miR-21 status. miR-21 (KO) suppressed cellular invasion of Panc-1 and MiaPaCa-2 cells, as well as the cellular proliferation of MiaPaCa-2 cells. Our data suggest that miR-21 is involved in the stemness of PDAC cells, may play roles in mesenchymal transition, and that miR-21 poses as a novel, functional biomarker for PDAC aggressiveness.

miR-802 Suppresses Acinar-to-Ductal Reprogramming During Early Pancreatitis and Pancreatic Carcinogenesis

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive tumor that is almost uniformly lethal in humans. Activating mutations of KRAS are found in >90% of human PDACs and are sufficient to promote acinar-to-ductal metaplasia (ADM) during tumor initiation. The roles of miRNAs in oncogenic Kras-induced ADM are incompletely understood.

METHODS

The Ptf1a^Cre/+LSL-Kras^G12D/+ and Ptf1a^Cre/+LSL-Kras^G12D/+LSL-p53R172H/⁺ and caerulein-induced acute pancreatitis mice models were used. mir-802 was conditionally ablated in acinar cells to study the function of miR-802 in ADM.

RESULTS

We show that miR-802 is a highly abundant and acinar-enriched pancreatic miRNA that is silenced during early stages of injury or oncogenic Kras^G12D-induced transformation. Genetic ablation of mir-802 cooperates with Kras^G12D by promoting ADM formation. miR-802 deficiency results in de-repression of the miR-802 targets Arhgef12, RhoA, and Sdc4, activation of RhoA, and induction of the downstream RhoA effectors ROCK1, LIMK1, COFILIN1, and EZRIN, thereby increasing F-actin rearrangement. mir-802 ablation also activates SOX9, resulting in augmented levels of ductal and attenuated expression of acinar identity genes. Consistently with these findings, we show that this miR-802-RhoA-F-actin network is activated in biopsies of pancreatic cancer patients and correlates with poor survival.

CONCLUSIONS

We show miR-802 suppresses pancreatic cancer initiation by repressing oncogenic Kras-induced ADM. The role of miR-802 in ADM fills the gap in our understanding of oncogenic Kras-induced F-actin reorganization, acinar reprogramming, and PDAC initiation. Modulation of the miR-802-RhoA-F-actin network may be a new strategy to interfere with pancreatic carcinogenesis.

Emerging Role of miR-345 and Its Effective Delivery as a Potential Therapeutic Candidate in Pancreatic Cancer and Other Cancers

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with high mortality, poor prognosis, and palliative treatments, due to the rapid upregulation of alternative compensatory pathways and desmoplastic reaction. miRNAs, small non-coding RNAs, have been recently identified as key players regulating cancer pathogenesis. Dysregulated miRNAs are associated with molecular pathways involved in tumor development, metastasis, and chemoresistance in PDAC, as well as other cancers. Targeted treatment strategies that alter miRNA levels in cancers have promising potential as therapeutic interventions. miRNA-345 (miR-345) plays a critical role in tumor suppression and is differentially expressed in various cancers, including pancreatic cancer (PC). The underlying mechanism(s) and delivery strategies of miR-345 have been investigated by us previously. Here, we summarize the potential therapeutic roles of miR-345 in different cancers, with emphasis on PDAC, for miRNA drug discovery, development, status, and implications. Further, we focus on miRNA nanodelivery system(s), based on different materials and nanoformulations, specifically for the delivery of miR-345.

Circular RNA hsa_circ_105039 promotes cardiomyocyte differentiation by sponging miR‑17 to regulate cyclinD2 expression

Previously it was found that hsa_circ_105039 was underexpressed in the heart tissue of patients with congenital heart disease (CHD). However, the function and mechanism of hsa_circ_105039 in CHD are unclear. In the present study, induced pluripotent stem (iPS) cells were differentiated into cardiomyocytes using 1% dimethyl sulfoxide (DMSO). Cell differentiation, viability, migration and apoptosis were measured before and following hsa_circ_105039 knockdown or overexpression. The results indicated that hsa_circ_105039 overexpression promoted cell differentiation, viability and migration; whereas apoptosis was simultaneously repressed. A luciferase reporter assay verified that hsa_circ_105039 acted as a sponge for microRNA (miR)‑17 and that cyclinD2 was a direct target of miR‑17. Furthermore, differentiation‑related genes and proteins were analyzed by reverse transcription‑quantitative PCR and western blotting, respectively. The results showed that hsa_circ_105039 could also upregulate the expression of differentiation‑related genes and proteins, including natriuretic peptide A, cardiac troponin I, GATA‑binding protein 4 and homobox transcription factor, in iPS cells. The results suggested that hsa_circ_105039 exerted a protective effect by promoting miR‑17/cyclinD2 in DMSO‑induced iPS cardiomyocytes, which indicated that hsa_circ_105039 is a potential key molecule for the diagnosis of CHD.

Role of non-coding RNAs in tumor progression and metastasis in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal types of cancer with an overall 5-year survival rate of less than 10%. The 1-year survival rate of patients with locally advanced or metastatic disease is abysmal. The aggressive nature of cancer cells, hypovascularization, extensive desmoplastic stroma, and immunosuppressive tumor microenvironment (TME) endows PDAC tumors with multiple mechanisms of drug resistance. With no obvious genetic mutation(s) driving tumor progression or metastatic transition, the challenges for understanding the biological mechanism(s) of these processes are paramount. A better understanding of the molecular and cellular mechanisms of these processes could lead to new diagnostic tools for patient management and new targets for therapeutic intervention. microRNAs (miRNAs) are an evolutionarily conserved gene class of short non-coding regulatory RNAs. miRNAs are an extensive regulatory layer that controls gene expression at the posttranscriptional level. This review focuses on preclinical models that functionally dissect miRNA activity in tumor progression or metastatic processes in PDAC. Collectively, these studies suggest an influence of miRNAs and RNA-RNA networks in the processes of epithelial to mesenchymal cell transition and cancer cell stemness. At a cell-type level, some miRNAs mainly influence cancer cell–intrinsic processes and pathways, whereas other miRNAs predominantly act in distinct cellular compartments of the TME to regulate fibroblast and immune cell functions and/or influence other cell types’ function via cell-to-cell communications by transfer of extracellular vesicles. At a molecular level, the influence of miRNA-mediated regulation often converges in core signaling pathways, including TGF-β, JAK/STAT, PI3K/AKT, and NF-κB.

The Role of microRNA in Pancreatic Cancer

MicroRNAs (miRNAs) are small ribonucleic acid molecules that play a key role in regulating gene expression. The increasing number of studies undertaken on the functioning of microRNAs in the tumor formation clearly indicates their important potential in oncological therapy. Pancreatic cancer is one of the deadliest cancers. The expression of miRNAs released into the bloodstream appears to be a good indicator of progression and evaluation of the aggressiveness of pancreatic cancer, as indicated by studies. The work reviewed the latest literature on the importance of miRNAs for pancreatic cancer development.

Exosomal microRNA in Pancreatic Cancer Diagnosis, Prognosis, and Treatment: From Bench to Bedside

Pancreatic cancer is the fourth leading cause of cancer death among men and women in the United States, and pancreatic ductal adenocarcinoma (PDAC) accounts for more than 90% of pancreatic cancer cases. PDAC is one of the most lethal gastrointestinal malignancies with an overall five-year survival rate of ~10%. Developing effective therapeutic strategies against pancreatic cancer is a great challenge. Novel diagnostic, prognostic, and therapeutic strategies are an immediate necessity to increase the survival of pancreatic cancer patients. So far, studies have demonstrated microRNAs (miRNAs) as sensitive biomarkers because of their significant correlation with disease development and metastasis. The miRNAs have been shown to be more stable inside membrane-bound vesicles in the extracellular environment called exosomes. Varieties of miRNAs are released into the body fluids via exosomes depending on the normal physiological or pathological conditions of the body. In this review, we discuss the recent findings on the diagnostic, prognostic, and therapeutic roles of exosomal miRNAs in pancreatic cancer.

MicroRNAs Deregulated in Intraductal Papillary Mucinous Neoplasm Converge on Actin Cytoskeleton-Related Pathways That Are Maintained in Pancreatic Ductal Adenocarcinoma

Intraductal papillary mucinous neoplasms (IPMN) are pancreatic cystic lesions that can develop into pancreatic ductal adenocarcinoma (PDAC). Although there is an increasing incidence of IPMN diagnosis, the mechanisms of formation and progression into invasive cancer remain unclear. MicroRNAs (miRNAs) are small non-coding RNAs, repressors of mRNA translation, and promising diagnostic biomarkers for IPMN and PDAC. Functional information on the role of early-altered miRNAs in this setting would offer novel strategies for tracking the IPMN-to-PDAC progression. In order to detect mRNAs that are likely to be under miRNA regulation in IPMNs, whole transcriptome and miRNome data from normal pancreatic tissue (n = 3) and IPMN lesions (n = 4) were combined and filtered according to negative correlation and miRNA-target prediction databases by using miRComb R package. Further comparison analysis with PDAC data allowed us to obtain a subset of miRNA-mRNA pairs shared in IPMN and PDAC. Functional enrichment analysis unravelled processes that are mainly related with cell structure, actin cytoskeleton, and metabolism. MiR-181a appeared as a master regulator of these processes. The expression of selected miRNA-mRNA pairs was validated by qRT-PCR in an independent cohort of patients (n = 40), and then analysed in different pancreatic cell lines. Finally, we generated a cellular model of HPDE cells stably overexpressing miR-181a, which showed a significant alteration of actin cytoskeleton structures accompanied by a significant downregulation of EPB41L4B and SEL1L expression. In situ hybridization of miR-181a and immunohistochemistry of EPB41L4B and SEL1L in pancreatic tissues (n = 4 Healthy; n = 3 IPMN; n = 4 PDAC) were also carried out. In this study, we offer insights on the potential implication of miRNA alteration in the regulation of structural and metabolic changes that pancreatic cells experience during IPMN establishment and that are maintained in PDAC.

Exosomes Derived from Pancreatic Cancer Cells Induce Osteoclast Differentiation Through the miR125a-5p/TNFRSF1B Pathway

Background

Pancreatic cancer (PC) was regarded as the 4th principal cause of cancer-related fatalities in the United States and patients usually suffered from severe nutrition deficiency, muscle wasting, as well as bone loss. In our previous research, we have found that PC-derived exosomes potentially initiate insulin resistance in skeletal muscle cells. However, the role of exosomes in the PC-related bone loss remains unknown.

Methods

The effect of PC-derived exosomes on the osteoclast differentiation and femoral bone structure in the orthotopic xenograft mouse model were investigated. MiRNA expression profiles were detected and a dual luciferase experiment was conducted to identify the direct target of miRNA.

Results

Our data showed that PC-derived exosomes significantly induced osteoclast differentiation and increased expression of NFAT2, TRAP, CTSK and MMP-9. The bone volume fraction and trabecular thickness of femur significantly reduced in osteoporotic model. Microarray analyses and luciferase reporter assay showed that the process was, at least partially, mediated by the miR-125a-5p/TNFRSF1B signaling pathways.

Conclusion

According to the results, novel insights have been claimed the effect of exosomes derived from PC on bone deterioration and explained correlation between PC and cancer-related bone loss.

Crosstalk between miRNAs and signaling pathways involved in pancreatic cancer and pancreatic ductal adenocarcinoma

Pancreatic cancer (PC) is the seventh leading cause of cancer-related deaths worldwide with 5-year survival rates below 8%. Most patients with PC and pancreatic ductal adenocarcinoma (PDAC) die after relapse and cancer progression as well as resistance to treatment. Pancreatic tumors contain a high desmoplastic stroma that forms a rigid mass and has a potential role in tumor growth and metastasis. PC initiates from intraepithelial neoplasia lesions leading to invasive cancer through various pathways. These lesions harbor particular changes in signaling pathways involved in the tumorigenesis process. These events affect both the epithelial cells, including the tumor and the surrounding stroma, and eventually lead to the formation of complex signaling networks. Genetic studies of PC have revealed common molecular features such as the presence of mutations in KRAS gene in more than 90% of patients, as well as the inactivation or deletion mutations of some tumor suppressor genes including TP53, CDKN2A, and SMAD4. In recent years, studies have also identified different roles of microRNAs in PC pathogenesis as well as their importance in PC diagnosis and treatment, and their involvement in various signaling pathways. In this study, we discussed the most common pathways involved in PC and PDAC as well as their role in tumorigenesis and progression. Furthermore, the miRNAs participating in the regulation of these signaling pathways in PC progression are summarized in this study. Therefore, understanding more about pathways involved in PC can help with the development of new and effective therapies in the future.

Development and clinical validation of a novel 9-gene prognostic model based on multi-omics in pancreatic adenocarcinoma

The prognoses of patients with pancreatic adenocarcinoma (PAAD) remain poor due to the lack of biomarkers for early diagnosis and effective prognosis prediction. RNA sequencing, single nucleotide polymorphism, and copy number variation data were downloaded from The Cancer Genome Atlas (TCGA). Univariate Cox regression was used to identify prognosis-related genes. GISTIC 2.0 was used to identify significantly amplified or deleted genes, and Mutsig 2.0 was used to analyze the mutation data. The Lasso method was used to construct a risk prediction model. The Rms package was used to evaluate the overall predictive performance of the signature. Finally, Western blot and polymerase chain reaction were performed to evaluate gene expression. A total of 54 candidate genes were obtained after integrating the genomic mutated genes and prognosis-related genes. The Lasso method was used to ascertain 9 characteristic genes, including UNC13B, TSPYL4, MICAL1, KLHDC7B, KLHL32, AIM1, ARHGAP18, DCBLD1, and CACNA2D4. The 9-gene signature model was able to help stratify samples at risk in the training and external validation cohorts. In addition, the overall predictive performance of our model was found to be superior to that of other models. KLHDC7B, AIM1, DCBLD1, TSPYL4, and MICAL1 were significantly highly expressed in tumor tissues compared to normal tissues. ARHGAP18 and CACNA2D4 had no difference in expression between tumor and normal tissues. UNC13B and KLHL32 expression in the normal group was higher than in the tumor group. The 9-gene signature constructed in this study can be used as a novel prognostic marker to predict the survival of patients with pancreatic adenocarcinoma.

A two-gene-based prognostic signature for pancreatic cancer

The purpose of this study was to identify a vital gene signature that has prognostic value for pancreatic cancer based on gene expression datasets from the Cancer Genome Atlas and Gene Expression Omnibus. A total of 34 genes were obtained by the univariate analysis, which were significantly associated with the overall survival of PC patients. After further analysis, Anillin (ANLN) and Histone H1c (HIST1H1C) were identified and considered to be the most significant prognostic genes among the 34 genes. A prognostic model based on these two genes was constructed, and successfully distinguished pancreatic cancer survival into high-risk and low-risk groups in the training set and testing set. Subsequently, independent predictive factors, including the age, margin condition and risk score, were then employed to construct the nomogram model. The area under curve for the nomogram model was 0.826 at 0.5 years and 0.726 at 1 year, and the C-index of the nomogram model was 0.664 higher than the others variables alone. These findings have indicated that high expression of ANLN and HIST1H1C predicted poor outcomes for patients with pancreatic cancer. The nomogram model based on the expression of two genes could be valuable for the guidance of clinical treatment.

Visual enhancement pattern during the delayed phase of enhanced CT as an independent prognostic factor in stage IV pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has substantial heterogeneity in biophysical features and in outcomes of patients. Identifying reliable pretreatment imaging biomarkers for PDAC with distant metastases (stage IV) is a key imperative. Our objective was to determine whether visual tumor enhancement pattern on enhanced computed tomography (CT) can be used as a prognostic factor in stage IV PDAC treated with chemotherapy.

METHODS

This is a retrospective cohort study of 133 patients with stage IV PDAC who underwent multiphasic enhanced CT before systemic chemotherapy. The enhancement pattern of PDAC was qualitatively categorized as hypoattenuation, isoattenuation, or hyperattenuation on each of the pancreatic, portal venous, and delayed phases. The effects of clinical prognostic factors and the visual tumor enhancement pattern on progression-free survival (PFS) and overall survival (OS) were assessed in univariate and multivariate analyses using Cox proportional hazards models.

RESULTS

On univariate analysis, the number of metastatic organs and the visual tumor enhancement pattern during the delayed phase were significantly associated with PFS (p = 0.003 and < 0.001, respectively) and OS (p = 0.005 and < 0.001, respectively). Multivariate analysis identified the number of metastatic organs (PFS, p = 0.021; OS, p = 0.041) and visual tumor enhancement pattern during the delayed phase (PFS, p < 0.001; OS, p < 0.001) as independent predictors of PFS and OS.

CONCLUSION

Visual enhancement pattern of PDAC on delayed phase enhanced CT appears to be associated with outcomes and could be a useful prognostic factor in stage IV PDAC, despite the need to add the delayed phase to CT protocol for pancreatic disease.

Nanoformulation of PROteolysis TArgeting Chimera targeting ‘undruggable’ c-Myc for the treatment of pancreatic cancer

Aim: To explore the anticancer activity of a novel BRD4 protein degrader ARV-825 (ARV) and its nanoformulation development (ARV-NP) for treatment of pancreatic cancer. Materials & methods: ARV-NP were prepared using nanoprecipitation method and characterized for their physicochemical properties and various anticancer cell culture assays. Results: ARV-NP (89.63 ± 16.39 nm) demonstrated good physical stability, negligible hemolysis and improved half-life of ARV. ARV-NP showed significant cytotoxicity, apoptosis and anticlonogenic effect in pancreatic cancer cells. Significant downregulation of target proteins BRD4, c-Myc, Bcl-2 and upregulation of apoptotic marker cleaved caspase-3 was observed. Most importantly, ARV-NP treatment significantly inhibited the cell viability of 3D tumor spheroids of pancreatic cancer. Conclusion: ARV-NP represents a novel therapeutic strategy for pancreatic cancer.

In Silico Transcriptomic Analysis of the Chloride Intracellular Channels (CLIC) Interactome Identifies a Molecular Panel of Seven Prognostic Markers in Patients with Pancreatic Ductal Adenocarcinoma

Background

Pancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis. In this context, the identification of biomarkers regarding the PDAC diagnosis, monitoring, and prognosis is crucial.

Objectives

The purpose of the current study was to investigate the differential gene expression profile of the chloride intracellular channel (CLIC) gene family network in patients with PDAC, in order to suggest novel biomarkers.

Methods

In silico techniques were used to construct the interactome of the CLIC gene family, identify the differentially expressed genes (DEGs) in PDAC as compared to healthy controls, and evaluate their potential prognostic role.

Results

Transcriptomic data of three microarray datasets were included, incorporating 114 tumor and 59 normal pancreatic samples. Twenty DEGs were identified; eight were up-regulated and twelve were downregulated. A molecular signature of seven genes (Chloride Intracellular Channel 1 – CLIC1; Chloride Intracellular Channel 3 – CLIC3; Chloride Intracellular Channel 4 – CLIC4; Ganglioside Induced Differentiation Associated Protein 1 – GDAP1; Ganglioside Induced Differentiation Associated Protein 1 Like 1 – GDAP1L1; Glutathione S-Transferase Pi 1 - GSTP1; Prostaglandin E Synthase 2 – PTGES2) were identified as prognostic markers associated with overall survival. Positive correlations were reported regarding the expression of CLIC1-CLIC3, CLIC4-CLIC5, and CLIC5-CLIC6. Finally, gene set enrichment analysis demonstrated the molecular functions and miRNA families (hsa‐miR‐122, hsa‐miR‐618, hsa‐miR‐425, and hsa‐miR‐518) relevant to the seven prognostic markers.

Conclusion

These outcomes demonstrate a seven-gene molecular panel that predicts the patients’ prospective survival following pancreatic resection for PDAC.

miR-431 Promotes Metastasis of Pancreatic Neuroendocrine Tumors by Targeting DAB2 Interacting Protein, a Ras GTPase Activating Protein Tumor Suppressor

The incidence of pancreatic neuroendocrine tumor (PNET) is increasing, and it presents with various clinical manifestations and an unfavorable survival rate. A better understanding of the drivers of PNET tumorigenesis is urgently needed. Distinct miRNA signatures have been identified for different stages of tumorigenesis in both human and mouse PNETs. The functions of these miRNAs are poorly understood. miR-431 is the most up-regulated miRNA in the metastatic signature. However, it is unknown whether miR-431 contributes to metastasis of PNETs. Herein, we show that miR-431 overexpression activates Ras/extracellular signal-regulated kinase (Erk) signaling and promotes epithelial-mesenchymal transition, migration/invasion in vitro, and metastasis in both xenograft and spontaneous mouse models of PNET. Treatment of PNET cells with Erk inhibitor or locked nucleic acids sequestering miR-431 inhibits invasion. Four target prediction modules and dual-luciferase reporter assays were used to identify potential mRNA targets of miR-431. A Ras GTPase activating protein tumor suppressor (RasGAP), DAB2 interacting protein (DAB2IP), was discovered as an miR-431 target. Overexpression of DAB2IP's rat homolog, but not its mutant defective in Ras GTPase activating protein activity, reverses miR-431's effect on promoting invasion, Erk phosphorylation, and epithelial-mesenchymal transition of PNETs. Taken together, miR-431 silences DAB2IP to active Ras/Erk and promote metastasis of PNETs. miR-431 may be targeted to manage metastatic PNETs.

MicroRNA-186-5p Inhibits Proliferation And Metastasis Of Esophageal Cancer By Mediating HOXA9

Objective

MicroRNA (miRNA) is an endogenous, non-coding small RNA that plays a key role in regulating organism biology and pathology. The aim of this study was to investigate the expression characteristics of microRNA-186-5p in esophageal cancer (ECa) and its correlation with clinical progression and prognosis, and to further explore its underlying mechanisms.

Methods

Real-time quantitative PCR (qRT-PCR) was used to detect microRNA-186-5p level in 45 pairs of ECa tissue samples and adjacent ones, and to analyze the expression of microRNA-186-5p and clinical progression of ECa and prognosis. The relationship between microRNA-186-5p level in ECa cell lines was further verified by qRT-PCR. Finally, the potential mechanism was explored using luciferase reporter gene assay and cell recovery experiment.

Results

QRT-PCR results revealed that the expression of microRNA-186-5p in ECa tissues was remarkably lower than that in adjacent tissues, and the difference was statistically significant. Compared with patients with high expression of microRNA-186-5p, patients with low expression of microRNA-186-5p had higher incidence of pathological stage and lower overall survival rate. Besides, compared with the miR-NC group, the microRNA-186-5p mimics group had a significant decrease in proliferation and metastasis ability of ECa cells. Subsequent qRT-PCR validation in ECa cell lines and tissues indicated a significant increase in HOXA9 expression and a negative correlation with microRNA-186-5p.

Conclusion

The expression of microRNA-186-5p was remarkably decreased in ECa, which was remarkably correlated with pathological stage, distant metastasis and poor prognosis of ECa. The results suggested that microRNA-186-5p may inhibit cell proliferation of ECa by regulating HOXA9.

Pancreatic Ductal Adenocarcinoma: Recent Updates

This Guest Editorial introduces this month's special Pancreatic Cancer Theme Issue, a series of reviews intended to highlight the pathologic to molecular profiles and diagnoses of benign and neoplastic pancreatic lesions.

Differentially Expressed microRNAs in MIA PaCa-2 and PANC-1 Pancreas Ductal Adenocarcinoma Cell Lines are Involved in Cancer Stem Cell Regulation

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, and thus better understanding of its molecular pathology is crucial for us to devise more effective treatment of this deadly disease. As cancer cell line remains a convenient starting point for discovery and proof-of-concept studies, here we report the miRNA expression characteristics of two cell lines, MIA PaCa-2 and PANC-1, and discovered three miRNAs (miR-7-5p, let-7d, and miR-135b-5p) that are involved in cancer stem cells (CSCs) suppression. After transfection of each miRNA's mimic into PANC-1 cells which exhibits higher stemness feature than MIA-PaCa-2 cells, partial reduction of CSC surface markers and inhibition of tumor sphere formation were observed. These results enlighten us to consider miRNAs as potential therapeutic agents for pancreatic cancer patients via specific and effective inhibition of CSCs.

Tumour infiltrating lymphocytes and immune-related genes as predictors of outcome in pancreatic adenocarcinoma

BACKGROUND

We investigated the correlation between pancreatic ductal adenocarcinoma patient prognosis and the presence of tumour infiltrating lymphocytes and expression of 521 immune system genes.

METHODS

Intratumoural CD3+, CD8+, and CD20+ lymphocytes were examined by immunohistochemistry in 12 PDAC patients with different outcomes who underwent pancreaticoduodenectomy. The results were correlated with gene expression profile using the digital multiplexed NanoString nCounter analysis system (NanoString Technologies, Seattle, WA, USA).

RESULTS

Twenty immune system genes were significantly differentially expressed in patients with a good prognosis relative to patients with a worse prognosis: TLR2 and TLR7 (Toll-like receptor superfamily); CD4, CD37, FOXP3, PTPRC (B cell and T cell signalling); IRF5, IRF8, STAT1, TFE3 (transcription factors); ANP32B, CCND3 (cell cycle); BTK (B cell development); TNF, TNFRF1A (TNF superfamily); HCK (leukocyte function); C1QA (complement system); BAX, PNMA1 (apoptosis); IKBKE (NFκB pathway). Differential expression was more than twice log 2 for TLR7, TNF, C1QA, FOXP3, and CD37.

DISCUSSION

Tumour infiltrating lymphocytes were present at higher levels in samples from patients with better prognosis. Our findings indicate that tumour infiltrating lymphocyte levels and expression level of the immune system genes listed above influence pancreatic ductal adenocarcinoma prognosis. This information could be used to improve selection of best responders to immune inhibitors.

Bioinformatic evidences and analysis of putative biomarkers in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human cancers. Aberrant expression of genes plays important role in the procession of PDAC. The analysis of gene expression profile will contribute to the research of carcinoma mechanism.

OBJECTIVE

This present study is focused to investigate the differentially expressed genes (DEGs) from 3 PDAC microarray datasets, which would provide candidate genes for putative biomarkers to understand the mechanism of PDAC and potential targets of treatment.

METHOD

Based on the overlap genes obtained from 3 GEO datasets, the hub genes were identified using STRING and Cytoscape plugin MCODE. The enrichment and function analysis were applied using DAVID. The protein-protein interaction network was performed using cBioPortal and UCSC Xena. The Oncomine was finally used to determine the candidate gene by analyzing their expression between pancreas sample and PDAC sample.

RESULTS

25 hub genes were selected from a total of 1006 DEGs from 3 GEO datasets, consisting of 14 upregulated genes and 11 downregulated genes. The overall decline of hub gene expression enriched in G1 phase of cell cycle in other subtypes of pancreatic cancer. Oncomine database was ultimately performed to determine the 8 candidate genes, including CXCL5, CCL20, NMU, F2R, ANXA1, EDNRA, LPAR6, and GNA15.

CONCLUSIONS

Conclusively, 8 candidate genes would become the potential PDAC combined biomarkers for diagnosis and therapeutic strategies.

The Clinical Potential of Oligonucleotide Therapeutics against Pancreatic Cancer

Although many diagnostic and therapeutic modalities for pancreatic cancer have been proposed, an urgent need for improved therapeutic strategies remains. Oligonucleotide therapeutics, such as those based on antisense RNAs, small interfering RNA (siRNA), microRNA (miRNA), aptamers, and decoys, are promising agents against pancreatic cancer, because they can identify a specific mRNA fragment of a given sequence or protein, and interfere with gene expression as molecular-targeted agents. Within the past 25 years, the diversity and feasibility of these drugs as diagnostic or therapeutic tools have dramatically increased. Several clinical and preclinical studies of oligonucleotides have been conducted for patients with pancreatic cancer. To support the discovery of effective diagnostic or therapeutic options using oligonucleotide-based strategies, in the absence of satisfactory therapies for long-term survival and the increasing trend of diseases, we summarize the current clinical trials of oligonucleotide therapeutics for pancreatic cancer patients, with underlying preclinical and scientific data, and focus on the possibility of oligonucleotides for targeting pancreatic cancer in clinical implications.

Enhancing the ligand efficiency of anti-HIV compounds targeting frameshift-stimulating RNA

Ribosomal frameshifting, a process whereby a translating ribosome is diverted from one reading frame to another on a contiguous mRNA, is an important regulatory mechanism in biology and an opportunity for therapeutic intervention in several human diseases. In HIV, ribosomal frameshifting controls the ratio of Gag and Gag-Pol, two polyproteins critical to the HIV life cycle. We have previously reported compounds able to selectively bind an RNA stemloop within the Gag-Pol mRNA; these compounds alter the production of Gag-Pol in a manner consistent with increased frameshifting. Importantly, they also display antiretroviral activity in human T-cells. Here, we describe new compounds with significantly reduced molecular weight, but with substantially maintained affinity and anti-HIV activity. These results suggest that development of more "ligand efficient" enhancers of ribosomal frameshifting is an achievable goal.