Overall Survival Of Pancreatic Ductal Adenocarcinoma Patients Research Articles

SKA3 Expression as a Prognostic Factor for Patients with Pancreatic Adenocarcinoma.

The spindle and kinetochore-associated complex subunit 3 (SKA3) is a protein essential for proper chromosome segregation during mitosis and thus responsible for maintaining genome stability. Although its involvement in the pathogenesis of various cancer types has been reported, the potential clinicopathological significance of SKA3 in pancreatic ductal adenocarcinoma (PDAC) has not been fully elucidated. Therefore, this study aimed to assess clinicopathological associations and prognostic value of SKA3 in PDAC. For this purpose, in-house immunohistochemical analysis on tissue macroarrays (TMAs), as well as a bioinformatic examination using publicly available RNA-Seq dataset, were performed. It was demonstrated that SKA3 expression at both mRNA and protein levels was significantly elevated in PDAC compared to control tissues. Upregulated mRNA expression constituted an independent unfavorable prognostic factor for the overall survival of PDAC patients, whereas altered SKA3 protein levels were associated with significantly better clinical outcomes. The last observation was particularly clear in the early-stage tumors. These findings render SKA3 a promising prognostic biomarker for patients with pancreatic ductal adenocarcinoma. However, further studies are needed to confirm this conclusion.

Abstract 4748: Aronia berry overcomes gemcitabine resistance by regulating the MYD88/NF-kB/P-glycoprotein pathway in pancreatic ductal adenocarcinoma

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is lethal, which is partly due to the limited efficacy of Gemcitabine (Gem)-based chemotherapy, resulting from the development of acquired resistance to this regimen. Aronia berry extract (ABE) is a natural source of phenolic compounds known for its anti-cancer properties. Previous research has highlighted the ability of ABE to help overcome chemoresistance to conventional chemotherapies in various cancers. In this study, we interrogated the ability of ABE to overcome Gem-resistance (Gem-R) in PDAC and identify specific pathway(s) responsible for this anti-cancer efficacy. Methods: We performed a series of in-vitro experiments in Gem-R cells to evaluate the synergistic effect of combined treatment with Gem and ABE. Furthermore, we conducted a genomewide transcriptomic analysis to identify the critical regulatory pathways associated with chemoresistance and potential therapeutic targets of ABE in Gem-R PDAC cells. The cell culture findings were validated in patient-derived 3D organoids. Results: The combined treatment with ABE and Gem in Gem-R cells exhibited significant synergistic anticancer effects on cell viability, proliferation, migration, and invasion. The transcriptomic analysis revealed that the NF-κB signaling pathway was associated with Gem-R (p<0.05), with a significant upregulation of MYD88. Additionally, MYD88 was significantly associated with overall survival in PDAC patients in the TCGA cohort (HR=1.58, P=0.045). The MYD88/NF-κB signaling is associated with chemoresistance as it can upregulate the efflux transporters like P-glycoprotein (P-gp). Our results confirmed that combined treatment inhibited the NF-κB signaling pathway by suppressing MYD88 and downregulating P-gp expression to overcome Gem-R. Finally, the combined treatment demonstrated superior anti-cancer activity in 3D organoids by reducing both their number and size (P<0.05). Conclusion: We provide novel insights into the potential of ABE in overcoming Gem-R in PDAC cells by targeting the MYD88/NF-κb/P-gp axis, which offers a safe and inexpensive approach for improving therapeutic outcomes in this fatal malignancy. Citation Format: Yuan Li, Caiming Xu, Haiyong Han, Ajay Goel. Aronia berry overcomes gemcitabine resistance by regulating the MYD88/NF-kB/P-glycoprotein pathway in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4748.

O148: Unlocking Enhanced Immunity in Pancreatic Ductal Adenocarcinoma: Activins Interplay with CAF-Stroma Mechanisms

Abstract SMAD4 is a tumour suppressor gene that is mutated in up to 60% of pancreatic ductal adenocarcinoma (PDAC) tumours. Activins are members of the TGF-b signalling superfamily which signal through SMAD4 and are generally associated with an oncogenic process, with differing effects on tumour and stromal cells, such as cancer associated fibroblasts (CAFs). We sought to further elucidate the role of activin within PDAC and perturb activin signalling in vitro and in vivo. Analysis was performed of publicly available human datasets alongside human and murine single-cell RNA-sequencing datasets to study the effect of activin expression on survival and tumourigenesis. We developed anti-activin monoclonal antibodies to perturb activin signalling in PDAC mice, with deep analysis of tumour composition including immune cells and CAFs via a multitude of basic science techniques. We demonstrated that circulating activin levels are higher in PDAC patients than in healthy volunteers, whilst activin overexpression is associated with reduced overall survival in PDAC patients. Activin was shown to be predominantly expressed by contractile (collagen-depositing) CAFs, as opposed to inflammatory CAFs. Activin expression co-localises with fibroblasts, and anti-activin antibodies can reduce the collagen content of dense PDAC tumours. Additionally, anti-activin antibodies led to a statistically significant increase in CD4 and CD8 T-cell infiltration into murine PDAC tumours. We have shown that activin is overexpressed in PDAC, and high expression is associated with a more aggressive disease process. Anti-activin antibodies can alter the composition of desmoplastic PDAC tumours and increase the immune infiltrate of these typically “immune cold” tumours.

An ion channel-based prognostic model identified TRPV2 and GJB3 as immunotherapy determinants in pancreatic cancer

BackgroundLess than 10% of people who have pancreatic ductal adenocarcinoma (PDAC) will survive the malignancy for five years. The ion channel genes-related biomarker and predictive model were needed for exploitation. MethodsDifferentially expressed ion channel genes (DEICGs) were detected in PDAC patients. GO and KEGG enrichment analysis was conducted on DEICGs. The prognostic genes were found using Cox regression analysis. After that, a risk model was created and examined. A nomogram was created based on independent predictive analysis. The molecular functions of two risk groups were explored. Immune checkpoint molecule expression was compared in two risk groups. We evaluated the possible cancer immunotherapy response in two risk groups using the TIDE method. We further examined how TRPV2 functions in PDAC as a potent oncogene and regulates the activity of macrophages by in vitro validation, including CCK8, EdU, and Transwell assays. ResultsA total of twenty-four DEICGs were found. Next, we discovered that two DEICGs (TRPV2 and GJB3) were connected to PDAC patients' overall survival (OS). The risk model was created and validated, and a nomogram was used to forecast the overall survival of PDAC patients. The high-risk group considerably accumulated oncogenic pathways. Furthermore, we discovered a correlation between the expression of critical immunological checkpoints and the risk score. Furthermore, patients in the high-risk category had a lower chance of benefiting from immune therapy. The HPA database confirmed that TRPV2 is expressed as a protein. Lastly, TRPV2 controls macrophage activity and acts as a potent oncogene in PDAC. ConclusionAltogether, this study suggested that two ion channel genes, TRPV2 and GJB3, were potential biomarkers for the prognosis of PDAC and immunotherapy targets, and the research will be crucial for creating novel PDAC treatment targets and predictive molecular indicators.

Abstract B082: Extinction of oncogenic Kras in genetic mouse models eradicates pancreatic cancer by inducing Fas-dependent apoptosis by CD8+ T cells

Abstract Oncogenic KrasG12D (Kras*) is critical for the initiation and maintenance of pancreatic ductal adenocarcinoma (PDAC), and a known repressor of tumor immunity. Conditional extinction of Kras* in genetic mouse models of PDAC leads to reactivation of Fas, CD8+ T cell mediated apoptosis, and complete eradication of tumors. Kras* extinction recruits CD4+ and CD8+ T cells, promotes the activation of putative antigen presenting CD11b−CD11c+ dendritic cells, and suppresses CD11b+ myeloid cell infiltration. Our findings shows that Kras* drives T cell suppression in PDAC. Mechanistically, Kras* mediated immune evasion involves epigenetic regulation of the death receptor Fas in cancer cells, via repression of its promoter region mediated by functional recruitment of DNA methyltransferase 1 (DNMT1), trimethylation of histone 3 at lysine 27 (H3K27me3), the histone methyltransferase EZH2, and suppression of acetylation of histone 3 at lysine 27 (H3K27ac). Further, analysis of human RNA sequencing reveals that Kras* expression levels inversely correlate with FAS expression and PDAC tumors with high KRAS demonstrate low CD8+ T cell infiltration, which is associated with shorter overall survival in PDAC patients. Given that specific and effective targeting of Kras* results in the CD8+ T cell mediated, Fas dependent apoptosis of cancer cells and eradication of PDAC in mice, this study highlights the direct role of Kras* in suppression of tumor immunity and supports a role for immunotherapy in combination with Kras* targeting strategies to control PDAC. Citation Format: Valerie S. LeBleu, Krishnan K. Mahadevan, Elena V. Ramirez, Yang Chen, Bingrui Li, Amari M. Sockwell, Mihai Gagea, Hikaru Sugimoto, Desiree Tampe, Michael Zeisberg, Haoqiang Ying, Abhinav K. Jain, Ronald A. DePinho, Aniban Maitra, Kathleen M. McAndrews, Raghu Kalluri. Extinction of oncogenic Kras in genetic mouse models eradicates pancreatic cancer by inducing Fas-dependent apoptosis by CD8+ T cells [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr B082.

Impact of hospice enrollment timing on overall survival and quality of life indicators in patients with pancreatic ductal adenocarcinoma (PDAC).

243 Background: This study aimed to examine the effects of hospice enrollment timing on survival and end-of-life quality of life indicators for pancreatic ductal adenocarcinoma (PDAC) patients. Methods: A retrospective chart review of 152 patients with biopsy-proven PDAC from August 2009 to December 2022 at a single center was conducted. Patients were categorized based on hospice enrollment timing: Early-Hospice (EH) (≥ 60 days before death), Late-hospice (LH) (< 60 days), and No Hospice (NH). Parameters assessed included overall survival (OS), palliative care service interaction, treatment lines, time from last chemotherapy treatment to death, hospital utilization after last chemotherapy treatment, documentation of advance care directives (ACD), and place of death. Statistical analysis was performed using Chi-squared test with Yates' continuity correction and Kruskal-Wallis test. The time-to-event endpoint was estimated using the Kaplan-Meier method. Results: Analysis of 152 patients showed that hospice enrollment timing did not significantly influence OS in PDAC patients (p=0.6). Median OS for EH (n=10), LH (n=84), and NH (n=58) groups were 10.1 months, 15.7 months, and 12.5 months, respectively. Subgroup analysis of patients with unresectable tumors at diagnosis (EH [n=7], LH [n=61], and NH [n=40]) showed no statistically significant difference in survival (9.19 vs. 12.22 vs. 9.08, p=0.08). The time from first interaction with the Palliative Care team to death was not different between groups. However, patients in EH had a notably longer median duration between their last chemotherapy session and death compared to LH and NH (201 vs. 43 vs. 31.5 days, p<0.01), as well as fewer days hospitalized after the last chemotherapy session (0.5 vs. 5 vs 8 days, p=0.02). Hospice enrollees had a substantially higher rate of documented ACD, and were far more likely to die at home. Conclusions: Although the timing of hospice enrollment did not significantly impact overall survival in PDAC patients, it played a significant role in influencing end-of-life quality of life indicators. Interaction with the palliative care team did not vary across groups, implying that hospice referral by oncology is acceptable and effective. However, documentation of ACDs for non-hospice enrollees was very low, a clear area for improvement.[Table: see text]

Regnase-1 downregulation promotes pancreatic cancer through myeloid-derived suppressor cell-mediated evasion of anticancer immunity

BackgroundPancreatitis is known to be an important risk factor for pancreatic ductal adenocarcinoma (PDAC). However, the exact molecular mechanisms of how inflammation promotes PDAC are still not fully understood. Regnase-1, an endoribonuclease, regulates immune responses by degrading mRNAs of inflammation-related genes. Herein, we investigated the role of Regnase-1 in PDAC.MethodsClinical significance of intratumor Regnase-1 expression was evaluated by immunohistochemistry in 39 surgically-resected PDAC patients. The functional role of Regnase-1 was investigated by pancreas-specific Regnase-1 knockout mice and Kras-mutant Regnase-1 knockout mice. The mechanistic studies with gene silencing, RNA immunoprecipitation sequencing (RIP-seq) and immune cell reconstitution were performed in human/mouse PDAC cell lines and a syngeneic orthotopic tumor transplantation model of KrasG12D-mutant and Trp53-deficient PDAC cells.ResultsRegnase-1 expression was negatively correlated with the clinical outcomes and an independent predictor of poor relapse-free and overall survival in PDAC patients. Pancreas-specific Regnase-1 deletion in mice promoteed pancreatic cancer with PMN-MDSC infiltration and shortened their survival. A syngeneic orthotopic PDAC model exhibited that Regnase-1 downregulation accelerated tumor progression via recruitment of intratumor CD11b+ MDSCs. Mechanistically, Regnase-1 directly negatively regulated a variety of chemokines/cytokines important for MDSC recruitment and activation, including CXCL1, CXCL2, CSF2, and TGFβ, in pancreatic cancer cells. We subsequently showed that IL-1β-mediated Regnase-1 downregulation recruited MDSCs to tumor sites and promoted pancreatic cancer progression via mitigation of cytotoxic T lympohocytes-mediated antitumor immunity.ConclusionsIL-1b-mediated Regnase-1 downregulation induces MDSCs and promotes pancreatic cancer through the evasion of anticancer immunity.

Identifying radiomics signatures in body composition imaging for the prediction of outcome following pancreatic cancer resection.

Computerized radiological image analysis (radiomics) enables the investigation of image-derived phenotypes by extracting large numbers of quantitative features. We hypothesized that radiomics features may contain prognostic information that enhances conventional body composition analysis. We aimed to investigate whether body composition-associated radiomics features hold additional value over conventional body composition analysis and clinical patient characteristics used to predict survival of pancreatic ductal adenocarcinoma (PDAC) patients. Computed tomography images of 304 patients undergoing elective pancreatic cancer resection were analysed. 2D radiomics features were extracted from skeletal muscle and subcutaneous and visceral adipose tissue (SAT and VAT) compartments from a single slice at the third lumbar vertebra. The study population was randomly split (80:20) into training and holdout subsets. Feature ranking with Least Absolute Shrinkage Selection Operator (LASSO) followed by multivariable stepwise Cox regression in 1000 bootstrapped re-samples of the training data was performed and tested on the holdout data. The fitted regression predictors were used as "scores" for a clinical (C-Score), body composition (B-Score), and radiomics (R-Score) model. To stratify patients into the highest 25% and lowest 25% risk of mortality compared to the middle 50%, the Harrell Concordance Index was used. Based on LASSO and stepwise cox regression for overall survival, ASA ≥3 and age were the most important clinical variables and constituted the C-score, and VAT-index (VATI) was the most important body composition variable and constituted the B-score. Three radiomics features (SATI_original_shape2D_Perimeter, VATI_original_glszm_SmallAreaEmphasis, and VATI_original_firstorder_Maximum) emerged as the most frequent set of features and yielded an R-Score. Of the mean concordance indices of C-, B-, and R-scores, R-score performed best (0.61, 95% CI 0.56-0.65, p<0.001), followed by the C-score (0.59, 95% CI 0.55-0.63, p<0.001) and B-score (0.55, 95% CI 0.50-0.60, p=0.03). Kaplan-Meier projection revealed that C-, B, and R-scores showed a clear split in the survival curves in the training set, although none remained significant in the holdout set. It is feasible to implement a data-driven radiomics approach to body composition imaging. Radiomics features provided improved predictive performance compared to conventional body composition variables for the prediction of overall survival of PDAC patients undergoing primary resection.

Identification and validation of the microRNAs and hub genes for pancreatic ductal adenocarcinoma by an integrated bioinformatic analysis.

In the progression of pancreatic ductal adenocarcinoma (PDAC), aberrant micro RNAs (miRNAs) expression plays a crucial role. This study sought to identify and validate the key miRNAs and potential target genes involved in PDAC. A bioinformatic analysis was conducted to determine their potential use as biomarkers and therapeutic targets. Gene profiling data sets (GSE41372 and GSE32688) were retrieved from the Gene Expression Omnibus database. Differentially expressed miRNAs (DEMs) with a P value <0.05, and |fold change| >2 was identified. The prognostic value of the DEMs was accessed using the online server Kaplan-Meier plotter. Further, gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed using DAVID 6.7. The protein-protein interaction analyses were conducted with STRING, and miRNA-hub gene networks were constructed using Cytoscape software. The PDAC cells were transfected with miRNA inhibitors or mimics. Cell Counting Kit-8 assays and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were used to examine cell proliferation and apoptosis, respectively. Wound-healing assays were performed to evaluate cell migration. Three DEMs (hsa-miR-21-5p, hsa-miR-135b-5p, and hsa-miR-222-3p) were identified. High expression levels of hsa-miR-21-5p, hsa-miR-135b-5p, or hsa-miR-222-3p predicted poor overall survival in PDAC patients. The pathway analysis revealed that the predicted target genes of the DEMs were closely related to several signaling pathways (including 'pathways in cancer', 'miRNAs in cancer', 'platinum drug resistance', 'lipid and atherosclerosis', and 'MAPK signaling pathway'). The MYC proto-oncogene (MYC), phosphate and tensin homolog gene (PTEN), poly(ADP-ribose) polymerase 1 (PARP1), von Hippel-Lindau (VHL), and fork head box p3 (FOXP3) were identified as potential target genes. The inhibition of hsa-miR-21-5p, hsa-miR-135b-5p, or hsa-miR-222-3p expression decreased cell proliferation. The overexpression of hsa-miR-21-5p, hsa-miR-135b-5p, or hsa-miR-222-3p facilitated PDAC cell migration. This study constructed the miRNA-hub gene network, which provides novel insights into the PDAC progression. Although further research is required, our results offer clues for new potential prognostic markers and therapeutic targets of PDAC.

Integrated analysis of Dendrobium nobile extract Dendrobin A against pancreatic ductal adenocarcinoma based on network pharmacology, bioinformatics, and validation experiments.

Background: Dendrobium nobile (D. nobile), a traditional Chinese medicine, has received attention as an anti-tumor drug, but its mechanism is still unclear. In this study, we applied network pharmacology, bioinformatics, and in vitro experiments to explore the effect and mechanism of Dendrobin A, the active ingredient of D. nobile, against pancreatic ductal adenocarcinoma (PDAC). Methods: The databases of SwissTargetPrediction and PharmMapper were used to obtain the potential targets of Dendrobin A, and the differentially expressed genes (DEGs) between PDAC and normal pancreatic tissues were obtained from The Cancer Genome Atlas and Genotype-Tissue Expression databases. The protein-protein interaction (PPI) network for Dendrobin A anti-PDAC targets was constructed based on the STRING database. Molecular docking was used to assess Dendrobin A anti-PDAC targets. PLAU, one of the key targets of Dendrobin A anti-PDAC, was immunohistochemically stained in clinical tissue arrays. Finally, in vitro experiments were used to validate the effects of Dendrobin A on PLAU expression and the proliferation, apoptosis, cell cycle, migration, and invasion of PDAC cells. Results: A total of 90 genes for Dendrobin A anti-PDAC were screened, and a PPI network for Dendrobin A anti-PDAC targets was constructed. Notably, a scale-free module with 19 genes in the PPI indicated that the PPI is highly credible. Among these 19 genes, PLAU was positively correlated with the cachexia status while negatively correlated with the overall survival of PDAC patients. Through molecular docking, Dendrobin A was found to bind to PLAU, and the Dendrobin A treatment led to an attenuated PLAU expression in PDAC cells. Based on clinical tissue arrays, PLAU protein was highly expressed in PDAC cells compared to normal controls, and PLAU protein levels were associated with the differentiation and lymph node metastatic status of PDAC. In vitro experiments further showed that Dendrobin A treatment significantly inhibited the proliferation, migration, and invasion, inducing apoptosis and arresting the cell cycle of PDAC cells at the G2/M phase. Conclusion: Dendrobin A, a representative active ingredient of D. nobile, can effectively fight against PDAC by targeting PLAU. Our results provide the foundation for future PDAC treatment based on D. nobile.

Challenges in Diagnosis and Treatment of Pancreatic Exocrine Insufficiency among Patients with Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is the most common malignancy of the pancreas and is associated with an extremely poor prognosis. Many PDAC patients suffer from profound nutritional complications such as nutrient deficiencies, weight loss, malnutrition, and cancer cachexia. These complications cause barriers to effective anticancer treatments, gravely influence their quality of life, and decrease their overall survival. Pancreatic exocrine insufficiency (PEI) is defined as impaired digestion due to inadequate secretion of pancreatic enzymes and is a common cause of malnutrition in PDAC. This review first summarizes the existing literature around malnutrition in PDAC, with a particular focus on PEI and its management with pancreatic enzyme replacement therapy (PERT). Second, we summarize existing guidelines and recommendations for the management of PEI among patients with PDAC. Lastly, we highlight potential gaps of knowledge of PEI among healthcare providers resulting in underdiagnosis and treatment, which may have implications for the quality of life and overall survival of PDAC patients.

The role of claudin 18.2 and HER-2 in pancreatic cancer outcomes.

To examine the prognostic value of claudin 18.2 (CLDN18.2) and human epidermal growth factor receptor-2 (HER-2) expression in patients with resected pancreatic ductal adenocarcinoma (PDAC). This study enrolled patients who underwent surgery and were diagnosed with PDAC at Suleyman Demirel University Hospital, Turkey between 2015 and 2019. Sixty-eight patients with resected PDAC treated at a medical oncology clinic were assessed. All patients were over the age of 18 years, underwent follow-up and treatment in our unit, and had pathology slides that we could access. Clinicopathological data were obtained from medical files, including the patients' age, sex, pathological parameters, and clinical stage according to the Eighth International Union against Cancer/American Joint Committee on Cancer. Patient survival and the period from the date of diagnosis to death were assessed in the follow-up data. There was no statistically significant difference between CLDN18.2 and HER-2 expression scores for samples and patient clinicopathological characteristics. No HER-2 expression scores of ≥2 were found in the samples. Only 25% (n = 17) of the samples had HER-2 expression scores of +1. CLDN18.2 expression was detected in 54.4% (n = 37) of the patient samples. CLDN18.2 expression scores were +1 in 30.8% (n = 21) of the patient samples, +2 in 16.2% (n = 11), and +3 in 7.4% (n = 5). When CLDN18.2 and HER-2 expression were compared, a statistically significant difference and moderate positive correlation were observed. No significant relationship between HER-2 expression and survival was observed in the survival analysis of PDAC patients; however, high CLDN18.2 expression was related to longer overall survival. Our study is the third to research CLDN18.2 expression in PDAC. HER-2 expression is low and CLDN18.2 expression is high in patients with PDAC. HER-2 expression is not related to overall survival but CLDN18.2 is related and may be used as a prognostic marker in patients with PDAC.

Single Cell RNA-Seq Identifies Immune-Related Prognostic Model and Key Signature-SPP1 in Pancreatic Ductal Adenocarcinoma.

There are no reliable biomarkers for early diagnosis or prognosis evaluation in pancreatic ductal adenocarcinoma (PDAC). Multiple scRNA-seq datasets for PDAC were retrieved from online databases and combined with scRNA-seq results from our previous study. The malignant ductal cells were identified through calculating copy number variation (CNV) scores. The robust markers of malignant ductal cells in PDAC were found. Five immune-related signatures, including SPP1, LINC00683, SNHG10, LINC00237, and CASC19, were used to develop a risk score formula to predict the overall survival of PDAC patients. We also constructed an easy-to-use nomogram, combining risk score, N stage, and margin status. The expression level of SPP1 was related to the prognosis and immune regulators. We found that SPP1 was mainly expressed in ductal cells and macrophages in PDAC. In conclusion, we constructed a promising prognostic model based on immune-related signatures for PDAC using scRNA-seq and TCGA_PAAD datasets.

A Paradoxical Role for Regulatory T Cells in the Tumor Microenvironment of Pancreatic Cancer.

Simple SummaryPancreatic cancer is one of the most lethal cancer types and its high refractoriness to therapies, including immunotherapy, has often been associated with the predominantly immune suppressive tumor microenvironment that characterizes pancreatic tumors. Regulatory T cells (Tregs) are generally considered as drivers of immune suppression in cancers. However, an increasing number of reports suggest a paradoxical association between tumor infiltration by Tregs and improved patient prognosis, in particular in gastrointestinal cancers. Here we show that Treg infiltration in pancreatic ductal adenocarcinomas (PDAC) is associated with better overall survival of patients.Pancreatic ductal adenocarcinoma (PDAC) is considered to be a poorly immunogenic cancer type that combines a low mutation burden with a strong immunosuppressive tumor microenvironment. Regulatory T cells (Tregs) are major drivers of immune suppression but their prognostic role, particularly in gastrointestinal malignancies, remains controversial. Lymphocytic infiltration in 122 PDAC samples was assessed by multispectral immunofluorescence with anti-Keratin, -CD3, -CD8, -FOXP3 and -CD163 antibodies. Differential infiltration by Tregs was analyzed in the context of transcriptomic profiles that were available for 65 tumors. High infiltration of CD3+CD8− (mainly CD4+) T cells and, especially, of the subset expressing FOXP3 (Tregs) was associated with improved patient survival, whilst cytotoxic CD3+CD8+ T cell infiltration did not have an impact on overall survival. Transcriptomic analysis revealed three signatures in PDAC tumors comprising of epithelial-mesenchymal transition (EMT)/stromal, metabolic, and secretory/pancreatic signature. However, none of these signatures explained differences in Treg infiltration. We show that Tregs associate with improved overall survival in PDAC patients. This effect was independent of cytotoxic T cell infiltration and the transcriptomic profiles of their respective tumors. These findings provide a new layer of complexity in the study of PDAC tumor microenvironment that must be considered when developing immunotherapeutic interventions for this disease.

The pancreatic cancer immune tumor microenvironment is negatively remodeled by gemcitabine while TGF-β receptor plus dual checkpoint inhibition maintains antitumor immune cells.

Pancreatic ductal adenocarcinoma (PDA) tumors have a highly immunosuppressive desmoplastic tumor microenvironment (TME) where immune checkpoint inhibition (ICI) therapy has been exceptionally ineffective. Transforming growth factor-β (TGF-β) receptor activation leads to cancer and immune cell proliferation and phenotype, and cytokine production leading to tumor progression and worse overall survival in PDA patients. We hypothesized that TGF-β receptor inhibition may alter PDA progression and antitumor immunity in the TME. Here, we used a syngeneic preclinical murine model of PDA to explore the impact of TGF-β pathway inhibitor galunisertib (GAL), dual checkpoint immunotherapy (anti-PD-L1 and CTLA-4), the chemotherapy gemcitabine (GEM), and their combinations on antitumor immune responses. Blockade of TGF-β and ICI in immune-competent mice bearing orthotopically injected murine PDA cells significantly inhibited tumor growth and was accompanied by antitumor M1 macrophage infiltration. In contrast, GEM treatment resulted in increased PDA tumor growth, decreased antitumor M1 macrophages, and decreased cytotoxic CD8+T cell subpopulation compared to control mice. Together, these findings demonstrate the ability of TGF-β inhibition with GAL to prime antitumor immunity in the TME and the curative potential of combining GAL with dual ICI. These preclinical results indicate that targeted inhibition of TGF-β may enhance the efficacy of dual immunotherapy in PDA. Optimal manipulation of the immune TME with non-ICI therapy may enhance therapeutic efficacy.

Circular RNA circ_0047744 suppresses the metastasis of pancreatic ductal adenocarcinoma by regulating the miR-21/SOCS5 axis

There is increasing evidence that circular RNAs (circRNAs) can serve as microRNA (miRNA) sponges to regulate metastasis of multiple tumors, including pancreatic ductal adenocarcinoma (PDAC). However, the role of the circRNA/miRNA regulatory network in metastasis of PDAC has not been elucidated. The purpose of this study is to explore the role of circ_0047744/miR-21/SOCS5 in the metastasis of PDAC. We found that circRNA_0047744 was weakly expressed in PDAC tissues and cell lines. The expression of circ_0047744 was negatively correlated with lymph node metastasis and positively correlated with overall survival in PDAC patients. Functionally, the overexpression of circ_0047744 suppressed cell migration and invasion in vitro and in vivo. Mechanistically, circ_0047744 could regulate SOCS5 expression by acting as a sponge of miR-21 to inhibit migration and invasion of PDAC cells. Our study demonstrates that circ_0047744 acts as an anti-oncogene to inhibit PDAC metastasis by regulating the miR-21/SOCS5 axis, indicating that circ_0047744 may be a potential novel therapeutic target for PDAC patients.

CES2 sustains HNF4α expression to promote pancreatic adenocarcinoma progression through an epoxide hydrolase-dependent regulatory loop

ObjectiveIntra-tumoral expression of the serine hydrolase carboxylesterase 2 (CES2) contributes to the activation of the pro-drug irinotecan in pancreatic ductal adenocarcinoma (PDAC). Given other potential roles of CES2, we assessed its regulation, downstream effects, and contribution to tumor development in PDAC. MethodsAssociation between the mRNA expression of CES2 in pancreatic tumors and overall survival was assessed using The Cancer Genome Atlas. Cell viability, clonogenic, and anchorage-independent growth assays as well as an orthotopic mouse model of PDAC were used to evaluate the biological relevance of CES2 in pancreatic cancer. CES2-driven metabolic changes were determined by untargeted and targeted metabolomic analyses. ResultsElevated tumoral CES2 mRNA expression was a statistically significant predictor of poor overall survival in PDAC patients. Knockdown of CES2 in PDAC cells reduced cell viability, clonogenic capacity, and anchorage-independent growth in vitro and attenuated tumor growth in an orthotopic mouse model of PDAC. Mechanistically, CES2 was found to promote the catabolism of phospholipids resulting in HNF4α activation through a soluble epoxide hydrolase (sEH)-dependent pathway. Targeting of CES2 via siRNA or small molecule inhibitors attenuated HNF4α protein expression and reduced gene expression of classical/progenitor markers and increased basal-like markers. Targeting of the CES2-sEH-HNF4α axis using small molecule inhibitors of CES2 or sEH reduced cell viability. ConclusionsWe establish a novel regulatory loop between CES2 and HNF4α to sustain the progenitor subtype and promote PDAC progression and highlight the potential utility of CES2 or sEH inhibitors for the treatment of PDAC as part of non-irinotecan-containing regimens.

Higher body mass index indicated better overall survival in pancreatic ductal adenocarcinoma patients: a real-world study of 2010 patients

BackgroundThe association between body mass index (BMI) and the overall survival (OS) of pancreatic ductal adenocarcinoma (PDAC) patients remains controversial and unclear,MethodA total of 2010 patients from a high-volume center were enrolled in the study. The OS of PDAC patients was evaluated based on restricted cubic spline (RCS), propensity score (PS) and multivariable risk adjustment analyses.ResultBMI was linearly related to the OS (total P = 0.004, nonlinear P = 0.124). BMI was analyzed as categorical data based on X-tile software-defined cutoffs and World Health Organization (WHO)-recommended cutoffs. Adjusted with confounding covariates, higher BMI manifested as a positive prognostic predictor. Furthermore, BMI was proven to be associated with the OS in the PS analysis. (UnderweightXtile vs. NormalXtileP = 0.003, OverweightXtile vs. NormalXtileP = 0.019; UnderweightWHO vs. NormalWHOP < 0.001, OverweightWHO vs. NormalWHOP = 0.024). It was also revealed that patients with higher BMI benefitted more from chemotherapy. (Adjusted hazard ratio (aHR): UnderweightXtile vs. NormalXtile vs. OverweightXtile: 0.565 vs. 0.474 vs. 0.409; UnderweightWHO vs. NormalWHO vs. OverweightWHO: 0.613 vs. 0.464 vs. 0.425).ConclusionAmong PDAC patients, there was a positive association between BMI and the OS, especially in patients treated with chemotherapy.

Plastin-3 is a diagnostic and prognostic marker for pancreatic adenocarcinoma and distinguishes from diffuse large B-cell lymphoma

BackgroundAltered Plastin-3 (PLS3; an actin-binding protein) expression was associated with human carcinogenesis, including pancreatic ductal adenocarcinoma (PDA). This study first assessed differentially expressed genes (DEGs) and then bioinformatically and experimentally confirmed PLS3 to be able to predict PDA prognosis and distinguish PDA from diffuse large B-cell lymphoma.MethodsThis study screened multiple online databases and revealed DEGs among PDA, normal pancreas, diffuse large B-cell lymphoma (DLBCL), and normal lymph node tissues and then focused on PLS3. These DEGs were analyzed for Gene Ontology (GO) terms, Kaplan–Meier curves, and the log-rank test to characterize their association with PDA prognosis. The receiver operating characteristic curve (ROC) was plotted, and Spearman’s tests were performed. Differential PLS3 expression in different tissue specimens (n = 30) was evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR).ResultsThere were a great number of DEGs between PDA and lymph node, between PDA and DLBCL, and between PDA and normal pancreatic tissues. Five DEGs (NET1, KCNK1, MAL2, PLS1, and PLS3) were associated with poor overall survival of PDA patients, but only PLS3 was further verified by the R2 and ICGC datasets. The ROC analysis showed a high PLS3 AUC (area under the curve) value for PDA diagnosis, while PLS3 was able to distinguish PDA from DLBCL. The results of Spearman's analysis showed that PLS3 expression was associated with levels of KRT7, SPP1, and SPARC. Differential PLS3 expression in different tissue specimens was further validated by RT-qPCR.ConclusionsAltered PLS3 expression was useful in diagnosis and prognosis of PDA as well as to distinguish PDA from DLBCL.

DeepPrognosis: Preoperative prediction of pancreatic cancer survival and surgical margin via comprehensive understanding of dynamic contrast-enhanced CT imaging and tumor-vascular contact parsing

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers and carries a dismal prognosis of ∼10% in five year survival rate. Surgery remains the best option of a potential cure for patients who are evaluated to be eligible for initial resection of PDAC. However, outcomes vary significantly even among the resected patients who were the same cancer stage and received similar treatments. Accurate quantitative preoperative prediction of primary resectable PDACs for personalized cancer treatment is thus highly desired. Nevertheless, there are a very few automated methods yet to fully exploit the contrast-enhanced computed tomography (CE-CT) imaging for PDAC prognosis assessment. CE-CT plays a critical role in PDAC staging and resectability evaluation. In this work, we propose a novel deep neural network model for the survival prediction of primary resectable PDAC patients, named as 3D Contrast-Enhanced Convolutional Long Short-Term Memory network (CE-ConvLSTM), which can derive the tumor attenuation signatures or patterns from patient CE-CT imaging studies. Tumor-vascular relationships, which might indicate the resection margin status, have also been proven to hold strong relationships with the overall survival of PDAC patients. To capture such relationships, we propose a self-learning approach for automated pancreas and peripancreatic anatomy segmentation without requiring any annotations on our PDAC datasets. We then employ a multi-task convolutional neural network (CNN) to accomplish both tasks of survival outcome and margin prediction where the network benefits from learning the resection margin related image features to improve the survival prediction. Our presented framework can improve overall survival prediction performances compared with existing state-of-the-art survival analysis approaches. The new staging biomarker integrating both the proposed risk signature and margin prediction has evidently added values to be combined with the current clinical staging system.