Current and Future Therapies for Pancreatic Ductal Adenocarcinoma

Quantitative characterization of the 3D self-organization of PDAC tumor spheroids reveals cell type and matrix dependence through advanced microscopy analysis

Pancreatic ductal adenocarcinoma (PDAC) is characterized by an abundant tumor-associated stroma composed from pancreatic stellate cells, which play a critical role in tumor progression. Developing accurate in vitro models requires understanding the complex interactions between tumor cells and their microenvironment. In this study, we present a quantitative imaging-based characterization of the three dimensional (3D) self-organization of PDAC tumour spheroids using a microfluidic platform that mimics key aspects of the tumor microenvironment. Our model incorporates collagen type I hydrogels to recreate the extracellular matrix, activated human pancreatic stellate cells (HPSCs), and various tumor cell types. Advanced imaging techniques, including Lattice Lightsheet Microscopy, allowed us to analyze the 3D growth and spatial organization of the spheroids, revealing intricate biomechanical interactions. Our results indicate that alterations in matrix properties-such as stiffness, pore size, and hydraulic permeability-due to variations in collagen concentration significantly influence the growth patterns and organization of PDAC spheroids, depending on tumor subtype and epithelial-mesenchymal phenotype. Higher collagen concentrations promoted larger spheroids in epithelial-like cell lines, while mesenchymal-type cells required increased collagen for self-organization into smaller spheroids. Furthermore, coculture with HPSCs affected spheroid formation distinctly based on each PDAC cell line's genetic and phenotypic traits. HPSCs had opposing effects on epithelial-like cell lines: one cell line exhibited enhanced spheroid growth, while another showed inhibited formation, whereas mesenchymal-like spheroids showed minimal impact. These results provide insights into tumor-stroma interactions, emphasizing the importance of the cell-specific and matrix-dependent factors for advancing our understanding of PDAC progression and informing future therapeutic strategies.

Prognostic Implications of Codon-Specific KRAS Mutations in Localized and Advanced Stages of Pancreatic Cancer

Introduction

While KRAS mutations represent the primary oncogenic driver in pancreatic ductal adenocarcinoma (PDAC), the association between codon-specific alterations and patient outcomes remains poorly elucidated, largely due to a lack of datasets coupling genomic profiling with rich clinical annotations across disease stages.

Patients and Methods

We utilized AACR's GENIE Biopharma Consortium Pancreas v1.2 dataset to test the associating of codon-specific KRAS mutations with clinicogenomic features and patient outcomes in PDAC patients diagnosed with localized (stages I-III) and advanced disease (stage IV). Overall survival was compared using Kaplan-Meier and multivariable Cox proportional hazards methods.

Results

Among 1,032 eligible patients, 949 (92%) exhibited mutant KRAS . These mutations were predominantly observed at G12D (n=390, 41%), G12V (n=305, 32%), and G12R (n=149, 16%). In the group of patients who presented with localized disease, those with G12V mutation had notably longer survival compared to G12D mutation ( P = 0.002). In contrast, patients with G12V mutation who presented with metastatic disease experienced shorter overall survival compared to those with G12R ( P = 0.005), and G12D mutations ( P = 0.009). Furthermore, no significant differences were observed in the frequencies of co-altered driver genes, including TP53 , CDKN2A , and SMAD4 , across the different KRAS mutations.

Conclusions

These findings demonstrated that codon-specific KRAS mutations impact PDAC outcomes differently based on disease stage at diagnosis. As studies testing KRAS inhibitors continue to emerge and mature, these data offer important contextual insights regarding survival outcomes associated with codon-specific KRAS mutations based on existing therapeutic approaches.

Identification of key regulators in pancreatic ductal adenocarcinoma using network theoretical approach

Pancreatic Ductal Adenocarcinoma (PDAC) is a devastating disease with poor clinical outcomes, which is mainly because of delayed disease detection, resistance to chemotherapy, and lack of specific targeted therapies. The disease's development involves complex interactions among immunological, genetic, and environmental factors, yet its molecular mechanism remains elusive. A major challenge in understanding PDAC etiology lies in unraveling the genetic profiling that governs the PDAC network. To address this, we examined the gene expression profile of PDAC and compared it with that of healthy controls, identifying differentially expressed genes (DEGs). These DEGs formed the basis for constructing the PDAC protein interaction network, and their network topological properties were calculated. It was found that the PDAC network self-organizes into a scale-free fractal state with weakly hierarchical organization. Newman and Girvan's algorithm (leading eigenvector (LEV) method) of community detection enumerated four communities leading to at least one motif defined by G (3,3). Our analysis revealed 33 key regulators were predominantly enriched in neuroactive ligand-receptor interaction, Cell adhesion molecules, Leukocyte transendothelial migration pathways; positive regulation of cell proliferation, positive regulation of protein kinase B signaling biological functions; G-protein beta-subunit binding, receptor binding molecular functions etc. Transcription Factor and mi-RNA of the key regulators were obtained. Recognizing the therapeutic potential and biomarker significance of PDAC Key regulators, we also identified approved drugs for specific genes. However, it is imperative to subject Key regulators to experimental validation to establish their efficacy in the context of PDAC.

Antibody-based delivery of interleukin-2 modulates the immunosuppressive tumor microenvironment and achieves cure in pancreatic ductal adenocarcinoma syngeneic mice

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and deadly type of cancer, with an extremely low five-year overall survival rate. To date, current treatment options primarily involve various chemotherapies, which often prove ineffective and are associated with substantial toxicity. Furthermore, immunotherapies utilizing checkpoint inhibitors have shown limited efficacy in this context, highlighting an urgent need for novel therapeutic strategies. This study investigates the preclinical efficacy of an innovative targeted therapy based on antibody-cytokine fusion proteins, specifically interleukin-2 (IL-2), a pivotal driver of cell-mediated immunity, fused to L19 antibody, which selectively binds to extra domain B of fibronectin (EDB-FN1) expressed in the tumor microenvironment.

METHODS

We tested the effectiveness of different immunocytokines through in vivo characterization in syngeneic C57BL/6J orthotopic mouse models of PDAC. Based on these results, we decided to focus on L19-IL2. To assess the efficacy of this immunocytokine we developed an ex-vivo immune-spheroid interaction platform derived from murine 3D pancreatic cultures, and telomerase reverse transcriptase (TERT) specific T-lymphocytes. Moreover, we evaluated the anti-cancer effect of L19-IL2 in combination with standard therapy in vivo experiments in PDAC mouse models. Tumor samples collected after the treatments were characterized for tumor infiltrating immune cell components by bulk RNA sequencing (RNA-seq) and spatial transcriptomics (Stereo-seq) analysis.

RESULTS

The tumor-targeted L19-IL2 fusion protein demonstrated potent, dose-dependent anti-tumor activity in mice with pancreatic tumors resistant to standard chemotherapy. Spatial Transcriptomics (ST) and RNA-seq analyses indicated that L19-IL2 treatment induced a significant influx of immune cells into the tumor microenvironment, with these cells expressing activation markers like granzymes, perforins, and the IL-2 receptors.

CONCLUSIONS

Our results demonstrated that L19-IL2 enhances immune infiltration and cytotoxicity, remodeling the "cold" tumor microenvironment (TME) in PDAC. This innovative antibody-cytokine fusion protein improves therapeutic outcomes, paving the way for novel targeted treatment strategies in PDAC.

Key genes and pathways in the molecular landscape of pancreatic ductal adenocarcinoma: A bioinformatics and machine learning study

Pancreatic ductal adenocarcinoma (PDAC) is recognized for its aggressive nature, dismal prognosis, and a notably low five-year survival rate, underscoring the critical need for early detection methods and more effective therapeutic approaches. This research rigorously investigates the molecular mechanisms underlying PDAC, with a focus on the identification of pivotal genes and pathways that may hold therapeutic relevance and prognostic value. Through the construction of a protein-protein interaction (PPI) network and the examination of differentially expressed genes (DEGs), the study uncovers key hub genes such as CDK1, KIF11, and BUB1, demonstrating their substantial role in the pathogenesis of PDAC. Notably, the dysregulation of these genes is consistent across a spectrum of cancers, positing them as potential targets for wide-ranging cancer therapeutics. This study also brings to the fore significant genes encoding intrinsically disordered proteins, in particular GPRC5A and KRT7, unveiling promising new pathways for therapeutic intervention. Advanced machine learning techniques were harnessed to classify PDAC patients with high accuracy, utilizing the key genetic markers as a dataset. The Support Vector Machine (SVM) model leveraged the hub genes to achieve a sensitivity of 91 % and a specificity of 85 %, while the RandomForest model notched a sensitivity of 91 % and specificity of 92.5 %. Crucially, when the identified genes were cross-referenced with TCGA-PAAD clinical datasets, a tangible correlation with patient survival rates was discovered, reinforcing the potential of these genes as prognostic biomarkers and their viability as targets for therapeutic intervention. This study's findings serve as a potent testament to the value of molecular analysis in enhancing the understanding of PDAC and in advancing the pursuit for more effective diagnostic and treatment strategies.

Pirfenidone antagonizes TGF-β1-mediated gabapentin resistance via reversal of desmoplasia and the 'cold' microenvironment in pancreatic cancer

Owing to the desmoplastic stroma constituted by cancer-associated fibroblasts (CAFs), few immune cells infiltrate the pancreatic ductal adenocarcinoma (PDAC). Gabapentin can impede the production of ketoacids by CAFs to support cancer cells. However, in our study, we discovered a dose-dependent increase in transforming growth factor β1 (TGF-β1) levels in cancer cells in response to gabapentin. This reverse increase of TGF-β1 contributes to 'Gabapentin-resistance', leading to the antitumor effects on PDAC cell lines are negatively negotiated in the presence of pancreatic stellate cells. Pirfenidone synergistically inhibited the growth and apoptosis resistance of PDAC when combined with Gabapentin. In a mouse orthotopic PDAC model, Fe3+-mediated coordination nanodrugs, which contain gabapentin, pirfenidone and the natural polyphenol (EGCG), efficiently promoted the infiltration of naïve CD8+ T cells (CD44lowCD62Lhigh) and the accumulation of inflammatory CAFs (α-SMAlowIL-6high). This led to a nearly two-fold increase in survival compared to the control. Furthermore, we identified a new subpopulation as Hmox1highiCAFs following treatment with our nanodrugs. Hmox1highiCAFs overexpressed the Cxcl10 receptor (Sdc4) and facilitated functional CD8+ T-cell infiltration through the Tnfsf9-Tnfrsf9 axis. Overall, our nanodrugs reshape the phenotype of CAFs and enhance functional CD8+ T-cell infiltration into tumors, holding the potential to be a safe and promising therapy for PDAC.

Unraveling the interplay: exploring signaling pathways in pancreatic cancer in the context of pancreatic embryogenesis

Pancreatic cancer continues to be a deadly disease because of its delayed diagnosis and aggressive tumor biology. Oncogenes and risk factors are being reported to influence the signaling pathways involved in pancreatic embryogenesis leading to pancreatic cancer genesis. Although studies using rodent models have yielded insightful information, the scarcity of human pancreatic tissue has made it difficult to comprehend how the human pancreas develops. Transcription factors like IPF1/PDX1, HLXB9, PBX1, MEIS, Islet-1, and signaling pathways, including Hedgehog, TGF-β, and Notch, are directing pancreatic organogenesis. Any derangements in the above pathways may lead to pancreatic cancer. TP53: and CDKN2A are tumor suppressor genes, and the mutations in TP53 and somatic loss of CDKN2A are the drivers of pancreatic cancer. This review clarifies the complex signaling mechanism involved in pancreatic cancer, the same signaling pathways in pancreas development, the current therapeutic approach targeting signaling molecules, and the mechanism of action of risk factors in promoting pancreatic cancer.

Structural Basis for Multivalent MUC16 Recognition and Robust Anti-Pancreatic Cancer Activity of Humanized Antibody AR9.6

Mucin-16 (MUC16) is a target for antibody-mediated immunotherapy in pancreatic ductal adenocarcinoma (PDAC) among other malignancies. The MUC16-specific monoclonal antibody AR9.6 has shown promise for PDAC immunotherapy and imaging. Here, we report the structural and biological characterization of the humanized AR9.6 antibody (huAR9.6). The structure of huAR9.6 was determined in complex with a MUC16 SEA (Sea urchin sperm, Enterokinase, Agrin) domain. Binding of huAR9.6 to recombinant, shed, and cell-surface MUC16 was characterized, and anti-PDAC activity was evaluated in vitro and in vivo. HuAR9.6 bound a discontinuous, SEA domain epitope with an overall affinity of 88 nmol/L. Binding affinity depended on the specific SEA domain(s) present, and glycosylation modestly enhanced affinity driven by favorable entropy and enthalpy and via distinct transition state thermodynamic pathways. Treatment with huAR9.6 reduced the in vitro growth, migration, invasion, and clonogenicity of MUC16-positive PDAC cells and patient-derived organoids (PDO). HuAR9.6 blocked MUC16-mediated ErbB and AKT activation in PDAC cells, PDOs, and patient-derived xenografts and induced antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity. More importantly, huAR9.6 treatment caused substantial PDAC regression in subcutaneous and orthotopic tumor models. The mechanism of action of huAR9.6 may depend on dense avid binding to homologous SEA domains on MUC16. The results of this study validate the translational therapeutic potential of huAR9.6 against MUC16-positive PDACs.

Minimally invasive pancreaticoduodenectomy: A favorable approach for frail patients with pancreatic cancer

BACKGROUND

Within the past decade, minimally invasive pancreaticoduodenectomy has been increasingly adopted in high-volume cancer centers. Amid broader trends of a growing older population, the numbers of frail patients with cancer are expected to increase. In this study, we compared the postoperative outcomes of open pancreaticoduodenectomy and minimally invasive pancreaticoduodenectomy in frail patients with pancreatic ductal adenocarcinoma.

METHODS

Using the pancreatectomy-targeted American College of Surgeons-National Surgical Quality Improvement Program database (2014-2021), we identified pancreaticoduodenectomy cases for pancreatic ductal adenocarcinoma. Patients with a modified frailty index ≥2 were considered frail. We performed 2:1 (open pancreaticoduodenectomy to minimally invasive pancreaticoduodenectomy) optimal pair propensity score matching for both patient- and disease-specific characteristics. We evaluated baseline covariate balance for homogeneity and assessed 30-day postoperative outcomes: complications, discharge destination, major morbidity, and mortality.

RESULTS

We identified 3,143 frail patients who underwent pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. Of those, 275 (9%) underwent minimally invasive pancreaticoduodenectomy. Minimally invasive pancreaticoduodenectomy was associated with a lower rate of any complications compared with open pancreaticoduodenectomy (43% vs 54%; P < .001), major morbidity (29% vs 35%; P = .042), and nonhome discharge (12% vs 17%; P = .022). When comparing the 2 minimally invasive pancreaticoduodenectomy approaches, robotic surgery was associated with fewer complications compared with laparoscopy (39% vs 51%; P = .040) and a lower mortality rate (1% vs 4%; P = .041) CONCLUSION: In frail patients with pancreatic cancer, minimally invasive pancreaticoduodenectomy was associated with better postoperative outcomes than open pancreaticoduodenectomy. This study builds on growing literature reporting that, when properly implemented, minimally invasive pancreaticoduodenectomy is associated with more favorable postoperative outcomes. Given the particularly high risk of complication in frail patients, implementing a preoperative frailty assessment can provide valuable insights to inform patient counseling.

A Nutrient-Deficient Microenvironment Facilitates Ferroptosis Resistance via the FAM60A-PPAR Axis in Pancreatic Ductal Adenocarcinoma

Ferroptosis, a nonapoptotic form of cell death, is an emerging potential therapeutic target for various diseases, including cancer. However, the role of ferroptosis in pancreatic cancer remains poorly understood. Pancreatic ductal adenocarcinoma (PDAC) is characterized by a poor prognosis and chemotherapy resistance, attributed to its high Kirsten rats arcomaviral oncogene homolog mutation rate and severe nutritional deficits resulting from a dense stroma. Several studies have linked rat sarcoma (RAS) mutations to ferroptosis, suggesting that inducing ferroptosis may be an effective strategy against oncogenic RAS-bearing tumors. We investigated the role of Family With Sequence Similarity 60 Member A (FAM60A) in this study, a protein closely associated with a poor prognosis and highly expressed in PDAC and tumor tissue from KrasG12D/+;Trp53R172H/+; Pdx1-Cre mice, in regulating ferroptosis, tumor growth, and gemcitabine sensitivity in vitro and in vivo. Our results demonstrate that FAM60A regulates 3 essential metabolic enzymes, ACSL1/4 and GPX4, to protect PDAC cells from ferroptosis. Furthermore, we found that YY1 transcriptionally regulates FAM60A expression by promoting its transcription, and the Hippo-YY1 pathway is restricted in the low-amino-acid milieu in the context of nutrient deprivation, leading to downstream suppression of peroxisome proliferator-activated receptor and ACSL1/4 and activation of GPX4 pathways. Importantly, FAM60A knockdown sensitized PDAC cells to gemcitabine treatment. A new understanding of FAM60A transcriptional regulation pattern in PDAC and its dual function in ferroptosis reliever and chemotherapy resistance is provided by our study. Targeting FAM60A may therefore offer a promising therapeutic approach for PDAC by simultaneously addressing 2 major features of the disease (high RAS mutation rate and tumor microenvironment nutrient deficiency) and preventing tumor cell metabolic adaptation.

Exploring the promising potential of induced pluripotent stem cells in cancer research and therapy

The advent of iPSCs has brought about a significant transformation in stem cell research, opening up promising avenues for advancing cancer treatment. The formation of cancer is a multifaceted process influenced by genetic, epigenetic, and environmental factors. iPSCs offer a distinctive platform for investigating the origin of cancer, paving the way for novel approaches to cancer treatment, drug testing, and tailored medical interventions. This review article will provide an overview of the science behind iPSCs, the current limitations and challenges in iPSC-based cancer therapy, the ethical and social implications, and the comparative analysis with other stem cell types for cancer treatment. The article will also discuss the applications of iPSCs in tumorigenesis, the future of iPSCs in tumorigenesis research, and highlight successful case studies utilizing iPSCs in tumorigenesis research. The conclusion will summarize the advancements made in iPSC-based tumorigenesis research and the importance of continued investment in iPSC research to unlock the full potential of these cells.

Overexpression of ZNF488 supports pancreatic cancer cell proliferation and tumorigenesis through inhibition of ferroptosis via regulating SCD1-mediated unsaturated fatty acid metabolism

BACKGROUND

Pancreatic cancer is a malignancy with high mortality. Once diagnosed, effective treatment strategies are limited and the five-year survival is extremely poor. Recent studies have shown that zinc finger proteins play important roles in tumorigenesis, including pancreatic cancer. However, it remains unknown on the clinical significance, function and underlying mechanisms of zinc finger protein 488 (ZNF488) during the development of pancreatic cancer.

METHODS

The clinical relevance of ZNF488 and stearoyl-CoA desaturase 1 (SCD1) was examined by analyzing the data from The Cancer Genome Atlas (TCGA) and immunohistochemical staining of the tissue microarray. Gain-of-function and loss-of-function experiments were performed by transfecting the cells with overexpressing lentivirus and siRNAs or shRNA lentivirus, respectively. The function of ZNF488 in pancreatic cancer was assessed by CCK8, colony formation, EdU staining, PI/Annexin V staining and xenografted tumorigenesis. Chip-qPCR assay was conducted to examine the interaction between ZNF488 and the promoter sequence of SCD1. Transcription activity was measured by dual luciferase reporter assay. mRNA and protein expression was detected by qRT-PCR and immunoblotting experiment, respectively. Fatty acid was quantified by gas chromatography mass spectrometry.

RESULTS

ZNF488 was overexpressed in pancreatic cancer samples compared with normal tissues. High expression of ZNF488 predicted the poor prognosis of the patients. In vitro, ZNF488 upregulation contributed to the EuU cooperation, proliferation and colony formation of MIAPaCa-2 and PANC-1 cells. Based on PI/Annexin V and trypan blue staining results, we showed that ZNF488 suppressed the ferroptosis and apoptosis of pancreatic cancer cells. Mechanistically, ZNF488 directly interacted with the promoter sequence of SCD1 gene and promoted its transcription activity, which resulted in enhanced palmitoleic and oleic acid production, as well as the peroxidation of fatty acid. In vivo, ZNF488 overexpression promoted the xenograted tumorigenesis of PANC-1, which was reversed by SCD1 knockdown. Importantly, combination of erastin and SCD1 inhibitors A939572 completely blunted the growth of ZNF488 overexpressed MIAPaCa-2 and PANC-1 cells. Usage of A939572 or erastin recovered the sensitivity of pancreatic cancer cells to the treatment of gemcitabine. Lastly, we found a positive correlation between ZNF488 and SCD1 in pancreatic cancer patients based on TCGA and immunohistochemical staining results.

CONCLUSION

Overexpression of ZNF488 suppresses the ferroptosis and apoptosis to support the growth and tumorigenesis of pancreatic cancer through augmentation of SCD1-mediated unsaturated fatty acid metabolism. Combination of SCD1 inhibitors, ferroptosis inducers or gemcitabine could be applied for the treatment of pancreatic cancer with overexpression of ZNF488.

Advances in Immunotherapeutics in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) accounts for up to 95% of all pancreatic cancer cases and is the seventh-leading cause of cancer death. Poor prognosis is a result of late presentation, a lack of screening tests and the fact some patients develop resistance to chemotherapy and radiotherapy. Novel therapies like immunotherapeutics have been of recent interest in pancreatic cancer. However, this field remains in its infancy with much to unravel. Immunotherapy and other targeted therapies have yet to yield significant progress in treating PDAC, primarily due to our limited understanding of the disease immune mechanisms and its intricate interactions with the tumour microenvironment (TME). In this review we provide an overview of current novel immunotherapies which have been studied in the field of pancreatic cancer. We discuss their mechanisms, evidence available in pancreatic cancer as well as the limitations of such therapies. We showcase the potential role of combining novel therapies in PDAC, postulate their potential clinical implications and the hurdles associated with their use in PDAC. Therapies discussed with include programmed death checkpoint inhibitors, Cytotoxic T-lymphocyte-associated protein 4, Chimeric Antigen Receptor-T cell therapy, oncolytic viral therapy and vaccine therapies including KRAS vaccines, Telomerase vaccines, Gastrin Vaccines, Survivin-targeting vaccines, Heat-shock protein (HSP) peptide complex-based vaccines, MUC-1 targeting vaccines, Listeria based vaccines and Dendritic cell-based vaccines.

Opportunities for Achieving the Cancer Moonshot Goal of a 50% Reduction in Cancer Mortality by 2047

On February 2, 2022, President Biden and First Lady Dr. Biden reignited the Cancer Moonshot, setting a new goal to reduce age-standardized cancer mortality rates by at least 50% over the next 25 years in the United States. We estimated trends in U.S. cancer mortality during 2000 to 2019 for all cancers and the six leading types (lung, colorectum, pancreas, breast, prostate, liver). Cancer death rates overall declined by 1.4% per year from 2000 to 2015, accelerating to 2.3% per year during 2016 to 2019, driven by strong declines in lung cancer mortality (-4.7%/year, 2014 to 2019). Recent declines in colorectal (-2.0%/year, 2010-2019) and breast cancer death rates (-1.2%/year, 2013-2019) also contributed. However, trends for other cancer types were less promising. To achieve the Moonshot goal, progress against lung, colorectal, and breast cancer deaths needs to be maintained and/or accelerated, and new strategies for prostate, liver, pancreatic, and other cancers are needed. We reviewed opportunities to prevent, detect, and treat these common cancers that could further reduce population-level cancer death rates and also reduce disparities.

SIGNIFICANCE

We reviewed opportunities to prevent, detect, and treat common cancers, and show that to achieve the Moonshot goal, progress against lung, colorectal, and breast cancer deaths needs to be maintained and/or accelerated, and new strategies for prostate, liver, pancreatic, and other cancers are needed. See related commentary by Bertagnolli et al., p. 1049. This article is highlighted in the In This Issue feature, p. 1027.

Systemic deuteration of SCID mice using the water-isotopologue deuterium oxide (D2 O) inhibits tumor growth in an orthotopic bioluminescent model of human pancreatic ductal adenocarcinoma

Since its initial discovery as a natural isotopologue of dihydrogen oxide (1 H2 O), extensive research has focused on the biophysical, biochemical, and pharmacological effects of deuterated water (2 H2 O [D2 O, also referred to as "heavy water"]). Using a panel of cultured human pancreatic ductal adenocarcinoma (PDAC) cells we have profiled (i) D2 O-induced phenotypic antiproliferative and apoptogenic effects, (ii) redox- and proteotoxicity-directed stress response gene expression, and (iii) phosphoprotein-signaling related to endoplasmic reticulum (ER) and MAP-kinase stress response pathways. Differential array analysis revealed early modulation of stress response gene expression in both BxPC-3 and PANC-1 PDAC cells elicited by D2 O (90%; ≤6 h; upregulated: HMOX1, NOS2, CYP2E1, CRYAB, DDIT3, NFKBIA, PTGS1, SOD2, PTGS2; downregulated: RUNX1, MYC, HSPA8, HSPA1A) confirmed by independent RT-qPCR analysis. Immunoblot-analysis revealed rapid (≤6 h) onset of D2 O-induced MAP-kinase signaling (p-JNK, p-p38) together with ER stress response upregulation (p-eIF2α, ATF4, XBP1s, DDIT3/CHOP). Next, we tested the chemotherapeutic efficacy of D2 O-based drinking water supplementation in an orthotopic PDAC model employing firefly luciferase-expressing BxPC-3-FLuc cells in SCID mice. First, feasibility and time course of systemic deuteration (30% D2 O in drinking water; 21 days) were established using time-resolved whole-body proton magnetic resonance imaging and isotope-ratio mass spectrometry-based plasma (D/H)-analysis. D2 O-supplementation suppressed tumor growth by almost 80% with downregulated expression of PCNA, MYC, RUNX1, and HSP70 while increasing tumor levels of DDIT3/CHOP, HO-1, and p-eIF2α. Taken together, these data demonstrate for the first time that pharmacological induction of systemic deuteration significantly reduces orthotopic tumor burden in a murine PDAC xenograft model.

Cuproptosis-related LncRNAs signature as biomarker of prognosis and immune infiltration in pancreatic cancer

Background: Pancreatic cancer (PC) is a malignant gastrointestinal tumor with a terrible prognosis. Cuproptosis is a recently discovered form of cell death. This study is intended to explore the relationship between cuproptosis-related lncRNAs (CRLncs) signature with the prognosis and the tumor microenvironment (TME) of PC. Methods: Transcript sequencing data of PC samples with clinical information were obtained from the Cancer Genome Atlas (TCGA). Univariate Cox regression analysis and LASSO regression analysis were employed to construct the prognostic signature based on CRLncs associated with PC survival. A nomogram was created according to this signature, and the signaling pathway enrichment was analyzed. Subsequently, we explored the link between this prognostic signature with the mutational landscape and TME. Eventually, drug sensitivity was predicted based on this signature. Results: Forty-six of 159 CRLncs were most significantly relevant to the prognosis of PC, and a 6-lncRNA prognostic signature was established. The expression level of signature lncRNAs were detected in PC cell lines. The AUC value of the ROC curve for this risk score predicting 5-year survival in PC was .944, which was an independent prognostic factor for PC. The risk score was tightly related to the mutational pattern of PC, especially the driver genes of PC. Single-sample gene set enrichment analysis (ssGSEA) demonstrated a significant correlation between signature with the TME of PC. Ultimately, compounds were measured for therapy in high-risk and low-risk PC patients, respectively. Conclusion: A prognostic signature of CRLncs for PC was established in the current study, which may serve as a promising marker for the outcomes of PC patients and has important forecasting roles for gene mutations, immune cell infiltration, and drug sensitivity in PC.

B7 Family Members in Pancreatic Ductal Adenocarcinoma: Attractive Targets for Cancer Immunotherapy

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, with a five-year survival rate of approximately 5-10%. The immune checkpoint blockade represented by PD-1/PD-L1 inhibitors has been effective in a variety of solid tumors but has had little clinical response in pancreatic cancer patients. The unique suppressive immune microenvironment is the primary reason for this outcome, and it is essential to identify key targets to remodel the immune microenvironment. Some B7 family immune checkpoints, particularly PD-L1, PD-L2, B7-H3, B7-H4, VISTA and HHLA2, have been identified as playing a significant role in the control of tumor immune responses. This paper provides a comprehensive overview of the recent research progress of some members of the B7 family in pancreatic cancer, which revealed that they can be involved in tumor progression through immune-dependent and non-immune-dependent pathways, highlighting the mechanisms of their involvement in tumor immune escape and assessing the prospects of their clinical application. Targeting B7 family immune checkpoints is expected to result in novel immunotherapeutic treatments for patients with pancreatic cancer.

Nano-drug delivery system for pancreatic cancer: A visualization and bibliometric analysis

Background: Nano drug delivery system (NDDS) can significantly improve the delivery and efficacy of drugs against pancreatic cancer (PC) in many ways. The purpose of this study is to explore the related research fields of NDDS for PC from the perspective of bibliometrics. Methods: Articles and reviews on NDDS for PC published between 2003 and 2022 were obtained from the Web of Science Core Collection. CiteSpace, VOSviewer, R-bibliometrix, and Microsoft Excel were comprehensively used for bibliometric and visual analysis. Results: A total of 1329 papers on NDDS for PC were included. The number of papers showed an upward trend over the past 20 years. The United States contributed the most papers, followed by China, and India. Also, the United States had the highest number of total citations and H-index. The institution with the most papers was Chinese Acad Sci, which was also the most important in international institutional cooperation. Professors Couvreur P and Kazuoka K made great achievements in this field. JOURNAL OF CONTROLLED RELEASE published the most papers and was cited the most. The topics related to the tumor microenvironment such as "tumor microenvironment", "tumor penetration", "hypoxia", "exosome", and "autophagy", PC treatment-related topics such as "immunotherapy", "combination therapy", "alternating magnetic field/magnetic hyperthermia", and "ultrasound", and gene therapy dominated by "siRNA" and "miRNA" were the research hotspots in the field of NDDS for PC. Conclusion: This study systematically uncovered a holistic picture of the performance of NDDS for PC-related literature over the past 20 years. We provided scholars to understand key information in this field with the perspective of bibliometrics, which we believe may greatly facilitate future research in this field.

The Extracellular Matrix: A Key Accomplice of Cancer Stem Cell Migration, Metastasis Formation, and Drug Resistance in PDAC

Pancreatic ductal adenocarcinoma (PDAC) is rich in dense fibrotic stroma that are composed of extracellular matrix (ECM) proteins. A disruption of the balance between ECM synthesis and secretion and the altered expression of matrix remodeling enzymes lead to abnormal ECM dynamics in PDAC. This pathological ECM promotes cancer growth, survival, invasion, and alters the behavior of fibroblasts and immune cells leading to metastasis formation and chemotherapy resistance, which contribute to the high lethality of PDAC. Additionally, recent evidence highlights that ECM, as a major structural component of the tumor microenvironment, is a highly dynamic structure in which ECM proteins establish a physical and biochemical niche for cancer stem cells (CSCs). CSCs are characterized by self-renewal, tumor initiation, and resistance to chemotherapeutics. In this review, we will discuss the effects of the ECM on tumor biological behavior and its molecular impact on the fundamental signaling pathways in PDAC. We will also provide an overview of how the different ECM components are able to modulate CSCs properties and finally discuss the current and ongoing therapeutic strategies targeting the ECM. Given the many challenges facing current targeted therapies for PDAC, a better understanding of molecular events involving the interplay of ECM and CSC will be key in identifying more effective therapeutic strategies to eliminate CSCs and ultimately to improve survival in patients that are suffering from this deadly disease.