Emerging roles for the IL-6 family of cytokines in pancreatic cancer

A bioprinted sea-and-island multicellular model for dissecting human pancreatic tumor-stroma reciprocity and adaptive metabolism

Pancreatic ductal adenocarcinoma (PDAC) presents a formidable clinical challenge due to its intricate microenvironment characterized by desmoplasia and complex tumor-stroma interactions. Conventional models hinder studying cellular crosstalk for therapeutic development. To recapitulate key features of PDAC masses, this study creates a novel sea-and-island PDAC tumor construct (s&i PTC). The s&i PTC consists of 3D-printed islands of human PDAC cells positioned within an interstitial extracellular matrix (ECM) populated by human cancer-associated fibroblasts (CAFs). This design closely mimics the in vivo desmoplastic architecture and nutrient-poor conditions. The model enables studying dynamic tumor-stroma crosstalk and signaling reciprocity, revealing both known and yet-to-be-discovered multicellular metabolic adaptations. Using the model, we discovered the orchestrated dynamic alterations of CAFs under nutrient stress, resembling critical in vivo human tumor niches, such as the secretion of pro-tumoral inflammatory factors. Additionally, nutrient scarcity induces dynamic alterations in the ECM composition and exacerbates poor cancer cell differentiation-features well-established in PDAC progression. Proteomic analysis unveiled the enrichment of proteins associated with aggressive tumor behavior and ECM remodeling in response to poor nutritional conditions, mimicking the metabolic stresses experienced by avascular pancreatic tumor cores. Importantly, the model's relevance to patient outcomes is evident through an inverse correlation between biomarker expression patterns in the s&i PTCs and PDAC patient survival rates. Key findings include upregulated MMPs and key ECM proteins (such as collagen 11 and TGFβ) under nutrient-avid conditions, known to be regulated by CAFs, alongside the concomitant reduction in E-cadherin expression associated with a poorly differentiated PDAC state under nutrient deprivation. Furthermore, elevated levels of hyaluronic acid (HA) and integrins in response to nutrient deprivation underscore the model's fidelity to the PDAC microenvironment. We also observed increased IL-6 and reduced α-SMA expression under poor nutritional conditions, suggesting a transition of CAFs from myofibroblastic to inflammatory phenotypes under a nutrient stress akin to in vivo niches. In conclusion, the s&i PTC represents a significant advancement in engineering clinically relevant 3D models of PDAC masses. It offers a promising platform for elucidating tumor-stroma interactions and guiding future therapeutic strategies to improve patient outcomes.

The pro-inflammatory cytokines IL-1β and IL-6 promote upregulation of the ST6GAL1 sialyltransferase in pancreatic cancer cells

The ST6GAL1 sialyltransferase is overexpressed in multiple cancers, including pancreatic ductal adenocarcinoma (PDAC). ST6GAL1 adds an α2-6-linked sialic acid to N-glycosylated membrane receptors, which consequently modulates receptor structure and function. While many studies have investigated the effects of ST6GAL1 on cell phenotype, there is a dearth of knowledge regarding mechanisms that regulate ST6GAL1 expression. In the current study, we evaluated the regulation of ST6GAL1 by two pro-inflammatory cytokines, IL-1β and IL-6, which are abundant within the PDAC tumor microenvironment. Cytokine activity was monitored using the Suit-2 PDAC cell line and two Suit-2-derived metastatic subclones, S2-013 and S2-LM7AA. For all three cell models, treatment with IL-1β or IL-6 increased the expression of ST6GAL1 protein and mRNA. Specifically, IL-1β and IL-6 induced expression of the ST6GAL1 YZ mRNA isoform, which is driven by the P3 promoter. The ST6GAL1 H and X isoforms were not detected. Promoter reporter assays confirmed that IL-1β and IL-6 activated transcription from the P3 promoter. We then examined downstream signaling mechanisms. IL-1β is known to signal through the NFκB transcription factor, whereas IL-6 signals through the STAT3 transcription factor. CUT&RUN experiments revealed that IL-1β promoted the binding of NFκB to the ST6GAL1 P3 promoter, and IL-6 induced the binding of STAT3 to the P3 promoter. Finally, we determined that inhibitors of NFκB and STAT3 blocked the upregulation of ST6GAL1 stimulated by IL-1β and IL-6, respectively. Together, these results highlight a novel molecular pathway by which cytokines within the tumor microenvironment stimulate the upregulation of ST6GAL1 in PDAC cells.

Pancreatic stellate cells and the interleukin family: Linking fibrosis and immunity to pancreatic ductal adenocarcinoma (Review)

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive form of cancer with a low survival rate. A successful treatment strategy should not be limited to targeting cancer cells alone, but should adopt a more comprehensive approach, taking into account other influential factors. These include the extracellular matrix (ECM) and immune microenvironment, both of which are integral components of the tumor microenvironment. The present review describes the roles of pancreatic stellate cells, differentiated cancer‑associated fibroblasts and the interleukin family, either independently or in combination, in the progression of precursor lesions in pancreatic intraepithelial neoplasia and PDAC. These elements contribute to ECM deposition and immunosuppression in PDAC. Therapeutic strategies that integrate interleukin and/or stromal blockade for PDAC immunomodulation and fibrogenesis have yielded inconsistent results. A deeper comprehension of the intricate interplay between fibrosis, and immune responses could pave the way for more effective treatment targets, by elucidating the mechanisms and causes of ECM fibrosis during PDAC progression.

TIM-4 increases the proportion of CD4+CD25+FOXP3+ regulatory T cells in the pancreatic ductal adenocarcinoma microenvironment by inhibiting IL-6 secretion

BACKGROUND

Currently, creating more effector T cells and augmenting their functions is a focal point in pancreatic ductal adenocarcinoma (PDAC) treatment research. T cell immunoglobulin domain and mucin domain molecule 4 (TIM-4), known for promoting cancer progression in various malignancies, is implicated in the suppressive immune microenvironment of tumors. Analyzing of the role of TIM-4 in the immune regulation of PDAC can offer novel insights for immune therapy.

METHODS

We analyzed the TIM-4 expression in tumor specimens from PDAC patients. Meanwhile, multiple fluorescent immunohistochemical staining was used to study the distribution characteristics of TIM-4, and through tissue microarrays, we explored its correlation with patient prognosis. The influence of TIM-4 overexpression on cell function was analyzed using RNA-seq. Flow cytometry and ELISA were used for verification. Finally, the relationship between TIM-4 and T lymphocytes was analyzed by tissue microarray, and the impacts of TIM-4 on T cell subsets were observed by cell coculture technology and a mouse pancreatic cancer in situ model.

RESULTS

In PDAC, TIM-4 is mainly expressed in tumor cells and negatively correlated with patient prognosis. TIM-4 influences the differentiation of Treg by inhibiting IL-6 secretion in pancreatic cancer cells and facilitates the proliferation of pancreatic cancer in mice. Additionally, the mechanism may be through the CD8+ effector T cells (CD8+Tc).

CONCLUSION

TIM-4 has the potential to be an immunotherapeutic target or to improve the efficacy of chemotherapy for PDAC.

Cytokines and Pancreatic Ductal Adenocarcinoma: Exploring Their Relationship with Molecular Subtypes and Prognosis

Pancreatic ductal adenocarcinoma (PDAC) is characterized by its poor prognosis. The current challenge remains the absence of predictive biomarkers. Cytokines are crucial factors in the pathogenesis and prognosis of PDAC. Furthermore, there is growing interest in differentiating between molecular subtypes of PDAC. The aim of our study is to evaluate the association between the analyzed cytokines and the molecular subtypes of PDAC and to determine their prognostic value. Cytokine levels were measured in 73 patients, and molecular subtypes were analyzed in 34 of these patients. Transforming Growth Factor Beta 2 (TGF-β2) levels were independently associated with the basal-like and null subtypes. In patients with locally advanced and metastatic PDAC, elevated levels of interleukin (IL)-1α, IL-1β, IL-6, IL-8, IL-9, and IL-15 were associated with a higher risk of progression during first-line treatment, and increased levels of IL-1β, IL-6, IL-8, IL-9, and IL-15 were related to increased mortality. Furthermore, a significant association was observed between higher percentiles of IL-6 and IL-8 and shorter progression-free survival (PFS) during first-line treatment, and between higher percentiles of IL-8 and shorter overall survival (OS). In the multivariate analysis, only elevated levels of IL-8 were independently associated with a higher risk of progression during first-line treatment and mortality. In conclusion, the results of our study suggest that cytokine expression varies according to the molecular subtype of PDAC and that cytokines also play a relevant role in patient prognosis.

Breaking Down Barriers in Drug Delivery by Stromal Remodeling Approaches in Pancreatic Cancer

Pancreatic cancer remains a formidable challenge in oncology due to its aggressive nature and limited treatment options. The dense stroma surrounding pancreatic tumors not only provides structural support but also presents a formidable barrier to effective therapy, hindering drug penetration and immune cell infiltration. This review delves into the intricate interplay between stromal components and cancer cells, highlighting their impact on treatment resistance and prognosis. Strategies for stromal remodeling, including modulation of cancer-associated fibroblasts (CAFs), pancreatic stellate cells (PSCs) activation states, and targeting extracellular matrix (ECM) components, are examined for their potential to enhance drug penetration and improve therapeutic efficacy. Integration of stromal remodeling with conventional therapies, such as chemotherapy and immunotherapy, is discussed along with the emerging field of intelligent nanosystems for targeted drug delivery. This comprehensive overview underscores the importance of stromal remodeling in pancreatic cancer treatment and offers insights into promising avenues for future research and clinical translation.

Hematoxylin and Eosin Architecture Uncovers Clinically Divergent Niches in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) represents one of the only cancers with an increasing incidence rate and is often associated with intra- and peri-tumoral scarring, referred to as desmoplasia. This scarring is highly heterogeneous in extracellular matrix (ECM) architecture and plays complex roles in both tumor biology and clinical outcomes that are not yet fully understood. Using hematoxylin and eosin (H&E), a routine histological stain utilized in existing clinical workflows, we quantified ECM architecture in 85 patient samples to assess relationships between desmoplastic architecture and clinical outcomes such as survival time and disease recurrence. By utilizing unsupervised machine learning to summarize a latent space across 147 local (e.g., fiber length, solidity) and global (e.g., fiber branching, porosity) H&E-based features, we identified a continuum of histological architectures that were associated with differences in both survival and recurrence. Furthermore, we mapped H&E architectures to a CO-Detection by indEXing (CODEX) reference atlas, revealing localized cell- and protein-based niches associated with outcome-positive versus outcome-negative scarring in the tumor microenvironment. Overall, our study utilizes standard H&E staining to uncover clinically relevant associations between desmoplastic organization and PDAC outcomes, offering a translatable pipeline to support prognostic decision-making and a blueprint of spatial-biological factors for modeling by tissue engineering methods.

CircRNAs in Pancreatic Cancer: New Tools for Target Identification and Therapeutic Intervention

We have reviewed the literature for circular RNAs (circRNAs) with efficacy in preclinical pancreatic-cancer related in vivo models. The identified circRNAs target chemoresistance mechanisms (n=5), secreted proteins and transmembrane receptors (n=15), transcription factors (n=9), components of the signaling- (n=11), ubiquitination- (n=2), autophagy-system (n=2), and others (n=9). In addition to identifying targets for therapeutic intervention, circRNAs are potential new entities for treatment of pancreatic cancer. Up-regulated circRNAs can be inhibited by antisense oligonucleotides (ASO), small interfering RNAs (siRNAs), short hairpin RNAs (shRNAs) or clustered regularly interspaced short-palindromic repeats-CRISPR associated protein (CRISPR-CAS)-based intervention. The function of down-regulated circRNAs can be reconstituted by replacement therapy using plasmids or virus-based vector systems. Target validation experiments and the development of improved delivery systems for corresponding agents were examined.

Irisin Ameliorate Acute Pancreatitis and Acinar Cell Viability through Modulation of the Unfolded Protein Response (UPR) and PPARγ-PGC1α-FNDC5 Pathways

Acute pancreatitis (AP) entails pancreatic inflammation, tissue damage and dysregulated enzyme secretion, including pancreatic lipase (PL). The role of irisin, an anti-inflammatory and anti-apoptotic cytokine, in AP and exocrine pancreatic stress is unclear. We have previously shown that irisin regulates PL through the PPARγ-PGC1α-FNDC5 pathway. In this study, we investigated irisin and irisin's pathway on AP in in vitro (AR42J-B13) and ex vivo (rat primary acinar) models using molecular, biochemical and immunohistochemistry methodology. Pancreatitis induction (cerulein (cer)) resulted in a significant up-regulation of the PPARγ-PGC1α-FNDC5 axis, PL expression and secretion and endoplasmic reticulum (ER) stress unfolded protein response (UPR) signal-transduction markers (CHOP, XBP-1 and ATF6). Irisin addition in the cer-pancreatitis state resulted in a significant down-regulation of the PPARγ-PGC1α-FNDC5 axis, PPARγ nucleus-translocation and inflammatory state (TNFα and IL-6) in parallel to diminished PL expression and secretion (in vitro and ex vivo models). Irisin addition up-regulated the expression of pro-survival UPR markers (ATF6 and XBP-1) and reduced UPR pro-apoptotic markers (CHOP) under cer-pancreatitis and induced ER stress (tunicamycin), consequently increasing cells viability. Irisin's pro-survival effect under cer-pancreatitis state was abolished under PPARγ inhibition. Our findings suggest irisin as a potential therapeutic option for AP via its ability to up-regulate pro-survival UPR signals and activate the PPARγ-PGC1α-FNDC5 pathway.

The Janus kinase 1 is critical for pancreatic cancer initiation and progression

Interleukin-6 (IL-6)-class inflammatory cytokines signal through the Janus tyrosine kinase (JAK)/signal transducer and activator of transcription (STAT) pathway and promote the development of pancreatic ductal adenocarcinoma (PDAC); however, the functions of specific intracellular signaling mediators in this process are less well defined. Using a ligand-controlled and pancreas-specific knockout in adult mice, we demonstrate in this study that JAK1 deficiency prevents the formation of KRASG12D-induced pancreatic tumors, and we establish that JAK1 is essential for the constitutive activation of STAT3, whose activation is a prominent characteristic of PDAC. We identify CCAAT/enhancer binding protein δ (C/EBPδ) as a biologically relevant downstream target of JAK1 signaling, which is upregulated in human PDAC. Reinstating the expression of C/EBPδ was sufficient to restore the growth of JAK1-deficient cancer cells as tumorspheres and in xenografted mice. Collectively, the findings of this study suggest that JAK1 executes important functions of inflammatory cytokines through C/EBPδ and may serve as a molecular target for PDAC prevention and treatment.

IL-6 Accelerates the Proliferation and Metastasis of Pancreatic Cancer Cells via the miR-455-5p/IGF-1R Axis

Background: Pancreatic cancer (PaC) is a highly malignant gastrointestinal tumor with invasive and metastatic characteristics. Interleukin-6 (IL-6), a negative prognostic marker, contributes to PaC progression. However, the mechanism of IL-6 in PaC is not yet fully understood. Methods: miR-455-5p levels were first tested by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in PaC tissues or cells. Subsequently, PaC cell-related functions were identified through CCK-8, Transwell, and Western blotting. Changes in miR-455-5p and IGF-1R expression were confirmed using RT-qPCR and Western blotting. miR-455-5p methylation was assessed by bisulfite sequencing PCR. Results: The authors discovered that miR-455-5p was expressed at low levels in PaC tissues and cells, and miR-455-5p expression was observably reduced by IL-6 in PaC cells. In addition, IL-6 dramatically induces miR-455-5p methylation in PaC cells. Functionally, the data revealed that IL-6 could facilitate the malignant properties of PaC cells, including proliferation, epithelial-mesenchymal transition, and metastasis. The authors found that miR-455-5p could suppress the progression of PaC cells by downregulating IGF-1R in PaC cells. Mechanistically, IL-6 downregulated miR-455-5p and upregulated IGF-1R, and miR-455-5p reduced IGF-1R expression through targeted binding. Conclusions: The authors demonstrated that the miR-455-5p/IGF-1R axis is necessary for the induction of IL-6 in PaC progression. The results here may provide a theoretical basis for the application of the IL-6/miR-455-5p/IGF-1R axis in the clinical therapy of PaC.

Targeting interleukin-6 as a treatment approach for peritoneal carcinomatosis

Peritoneal carcinomatosis (PC) is a complex manifestation of abdominal cancers, with a poor prognosis and limited treatment options. Recent work identifying high concentrations of the cytokine interleukin-6 (IL-6) and its soluble receptor (sIL-6-Rα) in the peritoneal cavity of patients with PC has highlighted this pathway as an emerging potential therapeutic target. This review article provides a comprehensive overview of the current understanding of the potential role of IL-6 in the development and progression of PC. We discuss mechansims by which the IL-6 pathway may contribute to peritoneal tumor dissemination, mesothelial adhesion and invasion, stromal invasion and proliferation, and immune response modulation. Finally, we review the prospects for targeting the IL-6 pathway in the treatment of PC, focusing on common sites of origin, including ovarian, gastric, pancreatic, colorectal and appendiceal cancer, and mesothelioma.

The Role of Pretreatment Serum Interleukin 6 in Predicting Short-Term Mortality in Patients with Advanced Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is notorious for its aggressive progression and dismal survival rates, with this study highlighting elevated interleukin 6 (IL-6) levels in patients as a key marker of increased disease severity and a potential prognostic indicator. Analyzing pre-treatment serum from 77 advanced PDAC patients via ELISA, the research determined optimal cutoff values for IL-6 and the IL-6:sIL-6Rα ratio using receiver operating characteristic curve analysis, which then facilitated the division of patients into low and high IL-6 groups, showing significantly different survival outcomes. Notably, high IL-6 levels correlated with adverse features such as poorly differentiated histology, higher tumor burden, and low albumin levels, indicating a stronger likelihood of poorer prognosis. With a median follow-up of 9.28 months, patients with lower IL-6 levels experienced markedly better median overall survival and progression-free survival than those with higher levels, underscoring IL-6's role in predicting disease prognosis. Multivariate analysis further confirmed IL-6 levels, alongside older age, and elevated neutrophil-to-lymphocyte ratio, as predictors of worse outcomes, suggesting that IL-6 could be a critical biomarker for tailoring treatment strategies in advanced PDAC, warranting further investigation into its role in systemic inflammation and the tumor microenvironment.

Acute pancreatitis: pathogenesis and emerging therapies

Acute pancreatitis is a severe inflammatory disorder with limited treatment options. Improved understanding of disease mechanisms has led to new and potential therapies. Here we summarize what we view as some of the most promising new therapies for treating acute pancreatitis, emphasizing the rationale of specific treatments based on disease mechanisms. Targeted pharmacologic interventions are highlighted. We explore potential treatment benefits and risks concerning reducing acute injury, minimizing complications, and improving long-term outcomes. Mechanisms associated with acute pancreatitis initiation, perpetuation, and reconstitution are highlighted, along with potential therapeutic targets and how these relate to new treatments.

Activation of gp130 signaling in T cells drives TH17-mediated multi-organ autoimmunity

The IL-6-gp130-STAT3 signaling axis is a major regulator of inflammation. Activating mutations in the gene encoding gp130 and germline gain-of-function mutations in STAT3 (STAT3GOF) are associated with multi-organ autoimmunity, severe morbidity, and adverse prognosis. To dissect crucial cellular subsets and disease biology involved in activated gp130 signaling, the gp130-JAK-STAT3 axis was constitutively activated using a transgene, L-gp130, specifically targeted to T cells. Activating gp130 signaling in T cells in vivo resulted in fatal, early onset, multi-organ autoimmunity in mice that resembled human STAT3GOF disease. Female mice had more rapid disease progression than male mice. On a cellular level, gp130 signaling induced the activation and effector cell differentiation of T cells, promoted the expansion of T helper type 17 (TH17) cells, and impaired the activity of regulatory T cells. Transcriptomic profiling of CD4+ and CD8+ T cells from these mice revealed commonly dysregulated genes and a gene signature that, when applied to human transcriptomic data, improved the segregation of patients with transcriptionally diverse STAT3GOF mutations from healthy controls. The findings demonstrate that increased gp130-STAT3 signaling leads to TH17-driven autoimmunity that phenotypically resembles human STAT3GOF disease.

Role of STAT3 in pancreatic cancer

Pancreatic cancer remains a serious and deadly disease, impacting people globally. There remain prominent gaps in the current understanding of the disease, specifically regarding the role of the signal transducer and activator of transcription (STAT) family of proteins in pancreatic tumors. STAT proteins, particularly STAT3, play important roles in pancreatic cancer, especially pancreatic ductal adenocarcinoma (PDAC), which is the most prevalent histotype. The role of STAT3 across a continuum of molecular processes, such as PDAC tumorigenesis and progression, immune escape, drug resistance and stemness, and modulation of the tumor microenvironment (TME), are only a tip of the iceberg. In some ways, the role of STAT3 in PDAC may hold greater importance than that of oncogenic Kirsten rat sarcoma virus (KRAS). This makes STAT3 a highly attractive target for developing targeted therapies for the treatment of pancreatic cancer. In this review, the current knowledge of STAT3 in pancreatic cancer has been summarized, particularly relating to STAT3 activation in cancer cells, cells of the TME, and the state of targeting STAT3 in pre-clinical and clinical trials of PDAC.

Molecular Design of Novel Inhibitor by Targeting IL-6Rα using Combined Pharmacophore and Experimentally Verified Plant Products with Scaffold-Hopping Techniques: A Dual Therapeutic Strategy for COVID-19 and Cancer

The IL-6/IL-6R/gp130 complex serves as a significant indicator of cytokine release syndrome in COVID-19 and chronic inflammation, increasing the risk of cancer. Therefore, we identified IL-6Rα as a potential target to block gp130 interaction. Notably, there has been no reception of approval for an orally available drug to serve this purpose, to date. In this study, we targeted IL-6Rα to inhibit IL-6Rα/gp130 interaction. The selection of the lead candidate L821 involved the amalgamation of three drug discovery approaches. This library was screened employing tertiary structure-based pharmacophore models followed by molecular docking models, scaffold-hopping, MM/PBSA as well as MM/GBSA analysis, and assessments of pKi and ADMET properties. After evaluating the binding interactions with key amino acids, 15 potential ligands were chosen, with the top ligand undergoing further investigation by means of molecular dynamics simulations. Considering the stability of the complexes, the strong interactions observed between ligand and residues of IL-6Rα/gp130, and the favorable binding free energy calculations, L821 emerged as the prime candidate for inhibiting IL-6Rα. Notably, L821 exhibited a docking-based binding affinity of -9.5 kcal/mol. Our study presents L821 as a promising inhibitor for future in vitro analysis, potentially combatting SARS-CoV-2-related cytokine storms and serving as an oncogenic drug therapy.

Structures of the interleukin 11 signalling complex reveal gp130 dynamics and the inhibitory mechanism of a cytokine variant

Interleukin (IL-)11, an IL-6 family cytokine, has pivotal roles in autoimmune diseases, fibrotic complications, and solid cancers. Despite intense therapeutic targeting efforts, structural understanding of IL-11 signalling and mechanistic insights into current inhibitors are lacking. Here we present cryo-EM and crystal structures of the human IL-11 signalling complex, including the complex containing the complete extracellular domains of the shared IL-6 family β-receptor, gp130. We show that complex formation requires conformational reorganisation of IL-11 and that the membrane-proximal domains of gp130 are dynamic. We demonstrate that the cytokine mutant, IL-11 Mutein, competitively inhibits signalling in human cell lines. Structural shifts in IL-11 Mutein underlie inhibition by altering cytokine binding interactions at all three receptor-engaging sites and abrogating the final gp130 binding step. Our results reveal the structural basis of IL-11 signalling, define the molecular mechanisms of an inhibitor, and advance understanding of gp130-containing receptor complexes, with potential applications in therapeutic development.

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

BACKGROUND

Pancreatitis 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.

METHODS

Clinical 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.

RESULTS

Regnase-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.

CONCLUSIONS

IL-1b-mediated Regnase-1 downregulation induces MDSCs and promotes pancreatic cancer through the evasion of anticancer immunity.

Identifying Effective Biomarkers for Accurate Pancreatic Cancer Prognosis Using Statistical Machine Learning

Pancreatic cancer (PC) has one of the lowest survival rates among all major types of cancer. Consequently, it is one of the leading causes of mortality worldwide. Serum biomarkers historically correlate well with the early prognosis of post-surgical complications of PC. However, attempts to identify an effective biomarker panel for the successful prognosis of PC were almost non-existent in the current literature. The current study investigated the roles of various serum biomarkers including carbohydrate antigen 19-9 (CA19-9), chemokine (C-X-C motif) ligand 8 (CXCL-8), procalcitonin (PCT), and other relevant clinical data for identifying PC progression, classified into sepsis, recurrence, and other post-surgical complications, among PC patients. The most relevant biochemical and clinical markers for PC prognosis were identified using a random-forest-powered feature elimination method. Using this informative biomarker panel, the selected machine-learning (ML) classification models demonstrated highly accurate results for classifying PC patients into three complication groups on independent test data. The superiority of the combined biomarker panel (Max AUC-ROC = 100%) was further established over using CA19-9 features exclusively (Max AUC-ROC = 75%) for the task of classifying PC progression. This novel study demonstrates the effectiveness of the combined biomarker panel in successfully diagnosing PC progression and other relevant complications among Egyptian PC survivors.

Suppression of the antitumoral activity of natural killer cells under indirect coculture with cancer-associated fibroblasts in a pancreatic TIME-on-chip model

BACKGROUND

Recently, natural killer (NK) cells emerged as a treatment option for various solid tumors. However, the immunosuppressive tumor immune microenvironment (TIME) can reduce the cytotoxic ability of NK cells in pancreatic ductal adenocarcinoma. Cancer-associated fibroblasts within the tumor stroma can suppress immune surveillance by dysregulating factors involved in the cellular activity of NK cells. Herein, the effect of activated pancreatic stellate cells (aPSCs) on NK cell-mediated anticancer efficacy under three-dimensional (3D) coculture conditions was investigated.

METHODS

3D cocultures of PANC-1 tumor spheroids (TSs) with aPSCs and NK-92 cells in a collagen matrix were optimized to identify the occurring cellular interactions and differential cytokine profiles in conditioned media using microchannel chips. PANC-1 TSs and aPSCs were indirectly cocultured, whereas NK-92 cells were allowed to infiltrate the TS channel using convective medium flow.

RESULTS

Coculture with aPSCs promoted PANC-1 TSs growth and suppressed the antitumor cytotoxic effects of NK-92 cells. Mutual inhibition of cellular activity without compromising migration ability was observed between aPSCs and NK-92 cells. Moreover, the reduced killing activity of NK-92 cells was found to be related with reduced granzyme B expression in NK cells.

CONCLUSIONS

Herein, a novel TIME-on-chip model based on the coculture of PANC-1 TSs, aPSCs, and NK-92 cells was described. This model may be useful for studying the detailed mechanisms underlying NK cells dysregulation and for exploring future therapeutic interventions to restore NK cell activity in the tumor microenvironment.

Earlier Diagnosis of Pancreatic Cancer: Is It Possible?

Pancreatic ductal adenocarcinoma has a very high mortality rate which has been only minimally improved in the last 30 years. This high mortality is closely related to late diagnosis, which is usually made when the tumor is large and has extensively infiltrated neighboring tissues or distant metastases are already present. This is a paradoxical situation for a tumor that requires nearly 15 years to develop since the first founding mutation. Response to chemotherapy under such late circumstances is poor, resistance is frequent, and prolongation of survival is almost negligible. Early surgery has been, and still is, the only approach with a slightly better outcome. Unfortunately, the relapse percentage after surgery is still very high. In fact, early surgery clearly requires early diagnosis. Despite all the advances in diagnostic methods, the available tools for improving these results are scarce. Serum tumor markers permit a late diagnosis, but their contribution to an improved therapeutic result is very limited. On the other hand, effective screening methods for high-risk populations have not been fully developed as yet. This paper discusses the difficulties of early diagnosis, evaluates whether the available diagnostic tools are adequate, and proposes some simple and not-so-simple measures to improve it.

Systemic Alterations in Type-2 Conventional Dendritic Cells Lead to Impaired Tumor Immunity in Pancreatic Cancer

Intratumoral T-cell dysfunction is a hallmark of pancreatic tumors, and efforts to improve dendritic cell (DC)-mediated T-cell activation may be critical in treating these immune therapy unresponsive tumors. Recent evidence indicates that mechanisms that induce dysfunction of type 1 conventional DCs (cDC1) in pancreatic adenocarcinomas (PDAC) are drivers of the lack of responsiveness to checkpoint immunotherapy. However, the impact of PDAC on systemic type 2 cDC2 development and function has not been well studied. Herein, we report the analysis of 3 cohorts, totaling 106 samples, of human blood and bone marrow (BM) from patients with PDAC for changes in cDCs. We found that circulating cDC2s and their progenitors were significantly decreased in the blood of patients with PDAC, and repressed numbers of cDC2s were associated with poor prognosis. Serum cytokine analyses identified IL6 as significantly elevated in patients with PDAC and negatively correlated with cDC numbers. In vitro, IL6 impaired the differentiation of cDC1s and cDC2s from BM progenitors. Single-cell RNA sequencing analysis of human cDC progenitors in the BM and blood of patients with PDAC showed an upregulation of the IL6/STAT3 pathway and a corresponding impairment of antigen processing and presentation. These results suggested that cDC2s were systemically suppressed by inflammatory cytokines, which was linked to impaired antitumor immunity.

IL-17A-producing CD8+ T cells promote PDAC via induction of inflammatory cancer-associated fibroblasts

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is characterised by an abundant desmoplastic stroma composed of cancer-associated fibroblasts (CAF) and interspersed immune cells. A non-canonical CD8+ T-cell subpopulation producing IL-17A (Tc17) promotes autoimmunity and has been identified in tumours. Here, we evaluated the Tc17 role in PDAC.

DESIGN

Infiltration of Tc17 cells in PDAC tissue was correlated with patient overall survival and tumour stage. Wild-type (WT) or Il17ra-/- quiescent pancreatic stellate cells (qPSC) were exposed to conditional media obtained from Tc17 cells (Tc17-CM); moreover, co-culture of Tc17-CM-induced inflammatory (i)CAF (Tc17-iCAF) with tumour cells was performed. IL-17A/F-, IL-17RA-, RAG1-deficient and Foxn1nu/nu mice were used to study the Tc17 role in subcutaneous and orthotopic PDAC mouse models.

RESULTS

Increased abundance of Tc17 cells highly correlated with reduced survival and advanced tumour stage in PDAC. Tc17-CM induced iCAF differentiation as assessed by the expression of iCAF-associated genes via synergism of IL-17A and TNF. Accordingly, IL-17RA controlled the responsiveness of qPSC to Tc17-CM. Pancreatic tumour cells co-cultured with Tc17-iCAF displayed enhanced proliferation and increased expression of genes implicated in proliferation, metabolism and protection from apoptosis. Tc17-iCAF accelerated growth of mouse and human tumours in Rag1-/- and Foxn1nu/nu mice, respectively. Finally, Il17ra-expressed by fibroblasts was required for Tc17-driven tumour growth in vivo.

CONCLUSIONS

We identified Tc17 as a novel protumourigenic CD8+ T-cell subtype in PDAC, which accelerated tumour growth via IL-17RA-dependent stroma modification. We described a crosstalk between three cell types, Tc17, fibroblasts and tumour cells, promoting PDAC progression, which resulted in poor prognosis for patients.

An oncolytic adenovirus coding for a variant interleukin 2 cytokine improves response to chemotherapy through enhancement of effector lymphocyte cytotoxicity, fibroblast compartment modulation and mitotic slippage

Pancreatic ductal adenocarcinoma (PDAC) is a highly treatment-resistant cancer. Currently, the only curative treatment for PDAC is surgery, but most patients are diagnosed with metastatic disease and thus outside the scope of surgery. The majority of metastatic patients receive chemotherapy, but responses are limited. New therapeutics are thus urgently needed for PDAC. One major limitation in treating PDAC has been the highly immunosuppressive tumor microenvironment (TME) which inhibits anti-cancer immune responses. We have constructed an oncolytic adenovirus coding for a variant the interleukin 2 molecule, Ad5/3-E2F-d24-vIL2 (also known as TILT-452, and "vIL-2 virus"), with preferential binding to IL-2 receptors on the surface of effector lymphocytes over T regulatory cells (T regs). In the present study this virus was evaluated in combination with nab-paclitaxel and gemcitabine chemotherapy in Panc02 mouse model. Ad5/3-E2F-d24-vIL2 showed marked PDAC cell killing in vitro, alongside induction of mitotic slippage and immunogenic cell death in PDAC cell lines, when combined with chemotherapy. Increased survival was seen in vivo with 80% of animals surviving long term, when compared to chemotherapy alone. Moreover, combination therapy mediated enhanced tumor growth control, without observable toxicities in internal organs or external features. Survival and tumor control benefits were associated with activation of tumor infiltrating immune cells, downregulation of inhibitory signals, change in fibroblast populations in the tumors and changes in intratumoral cytokines, with increased chemokine amounts (CCL2, CCL3, CCL4) and anti-tumor cytokines (IFN-γ and TNFα). Furthermore, vIL-2 virus in combination with chemotherapy efficiently induced tumor protection upon rechallenge, that was extended to a previously non-encountered cancer cell line. In conclusion, Ad5/3-E2F-d24-vIL2 is a promising immunotherapy candidate when combined with nab-paclitaxel and gemcitabine.

New insights into the role of adipocytes in pancreatic cancer progression: paving the way towards novel therapeutic targets

Pancreatic cancer (PC) remains one of the most lethal malignancies across the world, which is due to delayed diagnosis and resistance to current therapies. The interactions between pancreatic tumor cells and their tumor microenvironment (TME) allow cancer cells to escape from anti-cancer therapies, leading to difficulties in treating PC. With endocrine function and lipid storage capacity, adipose tissue can maintain energy homeostasis. Direct or indirect interaction between adipocytes and PC cells leads to adipocyte dysfunction characterized by morphological change, fat loss, abnormal adipokine secretion, and fibroblast-like transformation. Various adipokines released from dysfunctional adipocytes have been reported to promote proliferation, invasion, metastasis, stemness, and chemoresistance of PC cells via different mechanisms. Additional lipid outflow from adipocytes can be taken into the TME and thus alter the metabolism in PC cells and surrounding stromal cells. Besides, the trans-differentiation potential enables adipocytes to turn into various cell types, which may give rise to an inflammatory response as well as extracellular matrix reorganization to modulate tumor burden. Understanding the molecular basis behind the protumor functions of adipocytes in PC may offer new therapeutic targets.

Chronic effects of pulsed high intensity focused ultrasound aided delivery of gemcitabine in a mouse model of pancreatic cancer

Pulsed high intensity focused ultrasound (pHIFU) is a non-invasive method that allows to permeabilize pancreatic tumors through inertial cavitation and thereby increase the concentration of systemically administered drug. In this study the tolerability of weekly pHIFU-aided administrations of gemcitabine (gem) and their influence on tumor progression and immune microenvironment were investigated in genetically engineered KrasLSL.G12D/þ; p53R172H/þ; PdxCretg/þ (KPC) mouse model of spontaneously occurring pancreatic tumors. KPC mice were enrolled in the study when the tumor size reached 4-6 mm and treated once a week with either ultrasound-guided pHIFU (1.5 MHz transducer, 1 ms pulses, 1% duty cycle, peak negative pressure 16.5 MPa) followed by administration of gem (n = 9), gem only (n = 5) or no treatment (n = 8). Tumor progression was followed by ultrasound imaging until the study endpoint (tumor size reaching 1 cm), whereupon the excised tumors were analyzed by histology, immunohistochemistry (IHC) and gene expression profiling (Nanostring PanCancer Immune Profiling panel). The pHIFU + gem treatments were well tolerated; the pHIFU-treated region of the tumor turned hypoechoic immediately following treatment in all mice, and this effect persisted throughout the observation period (2-5 weeks) and corresponded to areas of cell death, according to histology and IHC. Enhanced labeling by Granzyme-B was observed within and adjacent to the pHIFU treated area, but not in the non-treated tumor tissue; no difference in CD8 + staining was observed between the treatment groups. Gene expression analysis showed that the pHIFU + gem combination treatment lead to significant downregulation of 162 genes related to immunosuppression, tumorigenesis, and chemoresistance vs gem only treatment.

Prediction of risk and overall survival of pancreatic cancer from blood soluble immune checkpoint-related proteins

Background

Immune checkpoint inhibition holds promise as a novel treatment for pancreatic ductal adenocarcinoma (PDAC). The clinical significance of soluble immune checkpoint (ICK) related proteins have not yet fully explored in PDAC.

Methods

We comprehensively profiled 14 soluble ICK-related proteins in plasma in 70 PDAC patients and 70 matched healthy controls. Epidemiological data of all subjects were obtained through structured interviews, and patients' clinical data were retrieved from electronical health records. We evaluated the associations between the biomarkers with the risk of PDAC using unconditional multivariate logistic regression. Consensus clustering (k-means algorithm) with significant biomarkers was performed to identify immune subtypes in PDAC patients. Prediction models for overall survival (OS) in PDAC patients were developed using multivariate Cox proportional hazards regression. Harrell's concordance index (C-index), time-dependent receiver operating characteristic (ROC) curve and calibration curve were utilized to evaluate performance of prediction models. Gene expressions of the identified ICK-related proteins in tumors from TCGA were analyzed to provide insight into underlying mechanisms.

Results

Soluble BTLA, CD28, CD137, GITR and LAG-3 were significantly upregulated in PDAC patients (all q < 0.05), and elevation of each of them was correlated with PDAC increased risk (all p < 0.05). PDAC patients were classified into soluble immune-high and soluble immune-low subtypes, using these 5 biomarkers. Patients in soluble immune-high subtype had significantly poorer OS than those in soluble immune-low subtype (log-rank p = 9.7E-03). The model with clinical variables and soluble immune subtypes had excellent predictive power (C-index = 0.809) for the OS of PDAC patients. Furthermore, the immune subtypes identified with corresponding genes' expression in PDAC tumor samples in TCGA showed an opposite correlation with OS to that of immune subtypes based on blood soluble ICK-related proteins (log-rank p =0.02). The immune-high subtype tumors displayed higher cytolytic activity (CYT) score than immune-low subtype tumors (p < 2E-16).

Conclusion

Five soluble ICK-related proteins were identified to be significantly associated with the risk and prognosis of PDAC. Patients who were classified as soluble immune-low subtype based on these biomarkers had better overall survival than those of the soluble immune-high subtype.

Dual IL-6 and CTLA-4 blockade regresses pancreatic tumors in a T cell- and CXCR3-dependent manner

This study aimed to enhance antitumor immune responses to pancreatic cancer via Ab-based blockade of IL-6 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). Mice bearing s.c. or orthotopic pancreatic tumors were treated with blocking Abs to IL‑6 and/or CTLA-4. In both tumor models, dual IL-6 and CTLA-4 blockade significantly inhibited tumor growth. Additional investigations revealed that dual therapy induced an overwhelming infiltration of T cells into the tumor as well as changes in CD4+ T cell subsets. Dual blockade therapy elicited CD4+ T cells to secrete increased IFN-γ in vitro. Likewise, in vitro stimulation of pancreatic tumor cells with IFN-γ profoundly increased tumor cell production of CXCR3-specific chemokines, even in the presence of IL-6. In vivo blockade of CXCR3 prevented orthotopic tumor regression in the presence of the combination treatment, demonstrating a dependence on the CXCR3 axis for antitumor efficacy. Both CD4+ and CD8+ T cells were required for the antitumor activity of this combination therapy, as their in vivo depletion via Abs impaired outcomes. These data represent the first report to our knowledge of IL-6 and CTLA‑4 blockade as a means to regress pancreatic tumors with defined operative mechanisms of efficacy.

Diagnostic value of combining preoperative inflammatory markers ratios with CA199 for patients with early-stage pancreatic cancer

BACKGROUND

An early diagnosis of pancreatic cancer (PC) is extremely difficult because of the lack of sensitive liquid biopsy methods and effective biomarkers. We attempted to evaluate whether circulating inflammatory marker could complement CA199 for the detection of early-stage PC.

METHODS

We enrolled 430 patients with early-stage PC, 287 patients with other pancreatic tumors (OPT), and 401 healthy controls (HC). The patients and HC were randomly divided into a training set (n = 872) and two testing sets (n₁ = 218, n₂ = 28). The receiver operating characteristic (ROC) curves were investigated to evaluate the diagnostic performance of circulating inflammatory markers ratios, CA199, and combinations of the markers ratios in the training set, which would then be validated in the two testing sets.

RESULTS

Circulating fibrinogen, neutrophils, and monocytes in patients with PC were significantly higher while circulating albumin, prealbumin, lymphocytes, and platelets of patients with PC were significantly lower compared to those of HC and OPT (all P < 0.05). The fibrinogen-to-albumin (FAR), fibrinogen-to-prealbumin (FPR), neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), monocyte-to-lymphocyte (MLR), and fibrinogen-to-lymphocyte (FLR) ratios were significantly higher while the prognostic nutrition index values (PNI) were lower in patients with PC than in HC and OPT (all P < 0.05). Combining the FAR, FPR, and FLR with CA199 exhibited the best diagnostic value for distinguishing patients with early-stage PC from HC with an area under the curve (AUC) of 0.964, and for distinguishing patients with early-stage PC from OPT with an AUC of 0.924 in the training sets. In the testing set, compared with HC, the combination markers had powerful efficiency for PC with an AUC 0.947 and AUC 0.942 when comparing PC with OPT. The AUC was 0.915 for the combination of CA199, FAR, FPR, and FLR for differentiating between patients with pancreatic head cancer (PHC) and other pancreatic head tumors (OPHT), and 0.894 for differentiating between patients with pancreatic body and tail cancer (PBTC) and other pancreatic body and tail tumors (OPBTT).

CONCLUSION

A combination of FAR, FPR, FLR, and CA199 may serve as a potential non-invasive biomarker for differentiating early-stage PC from HC and OPT, especially early-stage PHC.

Targeting Interleukin-6/Glycoprotein-130 Signaling by Raloxifene or SC144 Enhances Paclitaxel Efficacy in Pancreatic Cancer

Interleukine-6 plays a key role in the progression and poor survival in pancreatic ductal adenocarcinoma (PDAC). The present study aimed to clarify if targeting the interleukin-6/glycoprotein-130 signaling cascade using the small-molecule gp130 inhibitor SC144 or raloxifene, a non-steroidal selective estrogen receptor modulator, enhances paclitaxel efficacy. MTT/BrdU assays or TUNEL staining were performed to investigate cell viability, proliferation and apoptosis induction in L3.6pl and AsPC-1 human pancreatic cell lines. In vivo, effects were studied in an orthotopic PDAC mouse model. Tumor specimens were analyzed by qPCR, immunohistochemistry and ELISA. Combination of paclitaxel/raloxifene, but not paclitaxel/SC144, enhanced proliferation and viability inhibition and increased apoptosis compared to single treatment in vitro. Synergy score calculations confirmed an additive influence of raloxifene on paclitaxel. In the PDAC mouse model, both combinations of raloxifene/paclitaxel and SC144/paclitaxel reduced tumor weight and volume compared to single-agent therapy or control. Raloxifene/paclitaxel treatment decreased survivin mRNA expression and showed tendencies of increased caspase-3 staining in primary tumors. SC144/paclitaxel reduced interleukin-6 levels in mice's tumors and plasma. In conclusion, raloxifene or SC144 can enhance the anti-tumorigenic effects of paclitaxel, suggesting that paclitaxel doses might also be reduced in combined chemotherapy to lessen paclitaxel side effects.

Gp130 is expressed in pancreatic cancer and can be targeted by the small inhibitor molecule SC144

PURPOSE

Interleukin 6 (IL-6), Oncostatin M (OSM), and downstream effector STAT3 are pro-tumorigenic agents in pancreatic ductal adenocarcinoma (PDAC). Glycoprotein 130 (gp130) is a compound of the IL-6 and OSM receptor complex that triggers STAT3 signaling. SC144 is a small molecule gp130 inhibitor with anticancer activity. This study examines the gp130 expression in human PDAC specimens and the in vitro effects of SC144 in PDAC cell lines.

METHODS

Tissue micro-arrays were constructed from 175 resected human PDAC. The gp130 expression in tumor epithelium and stroma was determined by immunohistochemistry, and survival analysis was performed. Growth inhibition by SC144 was assessed in vitro using BrdU and MTT assays. Western blotting was performed to evaluate the SC144 effect on IL-6 and OSM signaling.

RESULTS

Gp130 was expressed in the epithelium of 78.8% and the stroma of 9.4% of the tumor samples. The median overall survival for patients with or without epithelial gp130 expression was 16.7 months and 15.9 months, respectively (p = 0.830). Patients with no stromal gp130 expression showed poorer survival than patients with stromal gp130 expression (median 16.2 and 22.9 months, respectively), but this difference did not reach significance (p = 0.144). SC144 inhibited cell proliferation and viability and suppressed IL-6- and OSM-stimulated STAT3^Y705 phosphorylation in PDAC cells.

CONCLUSION

Gp130 is expressed in the epithelium of most human PDAC, but stromal expression is rare. The small molecule gp130 inhibitor SC144 potently inhibits PDAC progression in vitro and may abrogate IL-6 or OSM/gp130/STAT3 signaling. These results suggest gp130 as a novel drug target for pancreatic cancer therapy.

Cytokines as Potential Therapeutic Targets and their Role in the Diagnosis and Prediction of Cancers

The death rate from cancer is declining as a result of earlier identification and more advanced treatments. Nevertheless, a number of unfavourable adverse effects, including prolonged, long-lasting inflammation and reduced immune function, usually coexist with anti-cancer therapies and lead to a general decline in quality of life. Improvements in standardized comprehensive therapy and early identification of a variety of aggressive tumors remain the main objectives of cancer research. Tumor markers in those with cancer are tumor- associated proteins that are clinically significant. Even while several tumor markers are routinely used, they don't always provide reliable diagnostic information. Serum cytokines are promising markers of tumor stage, prognosis, and responsiveness to therapy. In fact, several cytokines are currently proposed as potential biomarkers in a variety of cancers. It has actually been proposed that the study of circulatory cytokines together with biomarkers that are particular to cancer can enhance and accelerate cancer diagnosis and prediction, particularly via blood samples that require minimal to the absence of invasion. The purpose of this review was to critically examine relevant primary research literature in order to elucidate the role and importance of a few identified serum cytokines as prospective therapeutic targets in oncological diseases.

NFL-TBS.40-63 Peptide Gold Complex Nanovector: A Novel Therapeutic Approach to Increase Anticancer Activity by Breakdown of Microtubules in Pancreatic Adenocarcinoma (PDAC)

The role of the NFL-TBS.40-63 peptide is to destroy the microtubule network of target glioma cancer cells. Recently, we have conceived a gold-complex biotinylated NFL-TBS.40-63 (BIOT-NFL) to form a hybrid gold nanovector (BIOT-NFL-PEG-AuNPs). This methodology showed, for the first time, the ability of the BIOT-NFL-PEG-AuNPs to target the destruction of pancreatic cancer cells (PDAC) under experimental conditions, as well as detoxification and preclinical therapeutic efficacy regulated by the steric and chemical configuration of the peptide. For this aim, a mouse transplantation tumor model induced by MIA-PACA-2 cells was applied to estimate the therapeutic efficacy of BIOT-NFL-PEG-AuNPs as a nanoformulation. Our relevant results display that BIOT-NFL-PEG-AuNPs slowed the tumor growth and decreased the tumor index without effects on the body weight of mice with an excellent antiangiogenic effect, mediated by the ability of BIOT-NFL-PEG-AuNPs to alter the metabolic profiles of these MIA-PACA-2 cells. The cytokine levels were detected to evaluate the behavior of serum inflammatory factors and the power of BIOT-NFL-PEG-AuNPs to boost the immune system.

A Tumor Microenvironment Model of Pancreatic Cancer to Elucidate Responses toward Immunotherapy

Pancreatic cancer is a devastating malignancy with minimal treatment options. Standard-of-care therapy, including surgery and chemotherapy, is unsatisfactory, and therapies harnessing the immune system have been unsuccessful in clinical trials. Resistance to therapy and disease progression are mediated by the tumor microenvironment, which contains excessive amounts of extracellular matrix and stromal cells, acting as a barrier to drug delivery. There is a lack of preclinical pancreatic cancer models that reconstruct the extracellular, cellular, and biomechanical elements of tumor tissues to assess responses toward immunotherapy. To address this limitation and explore the effects of immunotherapy in combination with chemotherapy, a multicellular 3D cancer model using a star-shaped poly(ethylene glycol)-heparin hydrogel matrix is developed. Human pancreatic cancer cells, cancer-associated fibroblasts, and myeloid cells are grown encapsulated in hydrogels to mimic key components of tumor tissues, and cell responses toward treatment are assessed. Combining the CD11b agonist ADH-503 with anti-PD-1 immunotherapy and chemotherapy leads to a significant reduction in tumor cell viability, proliferation, metabolic activity, immunomodulation, and secretion of immunosuppressive and tumor growth-promoting cytokines.

Immune checkpoint blockade in pancreatic cancer: Trudging through the immune desert

Pancreatic cancer (PC) has exceptionally high mortality due to ineffective treatment strategies. Immunotherapy, which mobilizes the immune system to fight against cancer, has been proven successful in multiple cancers; however, its application in PC has met with limited success. In this review, we articulated that the pancreatic tumor microenvironment is immuno-suppressive with extensive infiltration by M2-macrophages and myeloid-derived suppressive cells but low numbers of cytotoxic T-cells. In addition, low mutational load and poor antigen processing, presentation, and recognition contribute to the limited response to immunotherapy in PC. Immune checkpoints, the critical targets for immunotherapy, have high expression in PC and stromal cells, regulated by tumor microenvironmental milieu (cytokine and metabolites) and cell-intrinsic mechanisms (epigenetic regulation, oncogenic signaling, and post-translational modifications). Combining immunotherapy with modulators of the tumor microenvironment may facilitate the development of novel therapeutic regimens to manage PC.

Cytokines chattering in pancreatic ductal adenocarcinoma tumor microenvironment

Pancreatic ductal adenocarcinoma (PDAC) tumor microenvironment (TME) consists of multiple cell types interspersed by dense fibrous stroma. These cells communicate through low molecular weight signaling molecules called cytokines. The cytokines, through their receptors, facilitate PDAC initiation, progression, metastasis, and distant colonization of malignant cells. These signaling mediators secreted from tumor-associated macrophages, and cancer-associated fibroblasts in conjunction with oncogenic Kras mutation initiate acinar to ductal metaplasia (ADM), resulting in the appearance of early preneoplastic lesions. Further, M1- and M2-polarized macrophages provide proinflammatory conditions and promote deposition of extracellular matrix, whereas myofibroblasts and T-lymphocytes, such as Th17 and T-regulatory cells, create a fibroinflammatory and immunosuppressive environment with a significantly reduced cytotoxic T-cell population. During PDAC progression, cytokines regulate the expression of various oncogenic regulators such as NFκB, c-myc, growth factor receptors, and mucins resulting in the formation of high-grade PanIN lesions, epithelial to mesenchymal transition, invasion, and extravasation of malignant cells, and metastasis. During metastasis, PDAC cells colonize at the premetastatic niche created in the liver, and lung, an organotropic function primarily executed by cytokines in circulation or loaded in the exosomes from the primary tumor cells. The indispensable contribution of these cytokines at every stage of PDAC tumorigenesis makes them exciting candidates in combination with immune-, chemo- and targeted radiation therapy.

Exosome-derived FGD5-AS1 promotes tumor-associated macrophage M2 polarization-mediated pancreatic cancer cell proliferation and metastasis

Inflammatory molecules and exosomes are crucial for signal transduction between tumor-associated macrophages and tumor cells. IL-6, a key inflammatory molecule secreted by M2 macrophages after polarization, can mediate malignant progression of pancreatic cancer (PC). However, the functions and mechanisms of IL-6 and tumor-derived exosomes in tumor-associated macrophages and PC remain unclear. Transcriptome chip and quantitative reverse transcription PCR experiments indicated that FGD5-AS1 induced IL-6 and high FGD5-AS1 expression correlated with the poor prognosis in PC patients. RNA pulldown, mass spectrometry, and dual luciferase reporter assays were used to identify the mechanism of exosomal FGD5-AS1 in promoting PC progression and M2 macrophage polarization. FGD5-AS1 exerted cancer-promoting functions when co-cultured with M2 macrophages. PC-derived exosomal FGD5-AS1 stimulated M2 macrophage polarization by activating STAT3/NF-κB pathway. FGD5-AS1 interacts with p300, resulting in STAT3 acetylation, thus promoting nuclear localization and transcriptional activity of STAT3/NF-κB. These data indicated that PC cells generate FGD5-AS1-rich exosomes, which cause M2 macrophage polarization to promote the malignant behaviors of PC cells. Targeting exosomal FGD5-AS1 may provide a potential diagnosis and treatment strategy for PC.

Establishment of the diagnostic and prognostic nomograms for pancreatic cancer with bone metastasis

Bone metastasis (BM) is rare in patients with pancreatic cancer (PC), but often neglected at the initial diagnosis and treatment. Bone metastasis is associated with a worse prognosis. This study was aimed to perform a large data analysis to determine the predictors and prognostic factors of BM in PC patients and to develop two nomograms to quantify the risks of BM and the prognosis of PC patients with BM. In the present study, we reviewed and collected the data of patients who were diagnosed as PC from 2010 to 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate logistic regression analyses were used together to screen and validate the risk factors for BM in PC patients. The independent prognostic factors for PC patients with BM were identified by Cox regression analysis. Finally, two nomograms were established via calibration curves, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA). This study included 16,474 PC patients from the SEER database, and 226 of them were diagnosed with BM. The risk factors of BM for PC patients covered age, grade, T stage, N stage, tumor size, and primary site. The independent prognostic factors for PC patients with BM included age, race, grade, surgery, and lung metastasis. The AUC of the diagnostic nomogram was 0.728 in the training set and 0.690 in the testing set. In the prognostic nomogram, the AUC values of 6/12/18 month were 0.781/0.833/0.849 in the training set and 0.738/0.781/0.772 in the testing set. The calibration curve and DCA furtherly indicated the satisfactory clinical consistency of the nomograms. These nomograms could be accurate and personalized tools to predict the incidence of BM in PC patients and the prognosis of PC patients with BM. The nomograms can help clinicians make more personalized and effective treatment choices.

Aberrant transcription factors in the cancers of the pancreas

Transcription factors (TFs) are essential for proper activation of gene set during the process of organogenesis, differentiation, lineage specificity. Reactivation or dysregulation of TFs regulatory networks could lead to deformation of organs, diseases including various malignancies. Currently, understanding the mechanism of oncogenesis became necessity for the development of targeted therapeutic strategy for different cancer types. It is evident that many TFs go awry in cancers of the pancreas such as pancreatic ductal adenocarcinoma (PDAC) and pancreatic neuroendocrine neoplasms (PanNENs). These mutated or dysregulated TFs abnormally controls various signaling pathways in PDAC and PanNENs including RTK, PI3K-PTEN-AKT-mTOR, JNK, TGF-β/SMAD, WNT/β-catenin, SHH, NOTCH and VEGF which in turn regulate different hallmarks of cancer. Aberrant regulation of such pathways have been linked to the initiation, progression, metastasis, and resistance in pancreatic cancer. As of today, a number of TFs has been identified as crucial regulators of pancreatic cancer and a handful of them shown to have potential as therapeutic targets in pre-clinical and clinical settings. In this review, we have summarized the current knowledge on the role and therapeutic usefulness of TFs in PDAC and PanNENs.

Smart hypoxia-responsive transformable and charge-reversible nanoparticles for the deep penetration and tumor microenvironment modulation of pancreatic cancer

The compact extracellular matrix (ECM) of pancreatic ductal adenocarcinoma (PDAC) is the major physical barrier that hinders the delivery of anti-tumor drugs, leading to strong inherent chemotherapy resistance as well as establishing an immunosuppressive tumor microenvironment (TME). However, forcibly destroying the stroma barrier would break the balance of delicate signal transduction and dependence between tumor cells and matrix components. Uncontrollable growth and metastasis would occur, making PDAC more difficult to control. Hence, we design and construct an aptamer-decorated hypoxia-responsive nanoparticle s(DGL)n@Apt co-loading gemcitabine monophosphate and STAT3 inhibitor HJC0152. This nanoparticle can reverse its surficial charge in the TME, and reduce the size triggered by hypoxia. The released ultra-small DGL particles loading gemcitabine monophosphate exhibit excellent deep-tumor penetration, chemotherapy drugs endocytosis promotion, and autophagy induction ability. Meanwhile, HJC0152 inhibits overactivated STAT3 in both tumor cells and tumor stroma, softens the stroma barrier, and reeducates the TME into an immune-activated state. This smart codelivery strategy provides an inspiring opportunity in PDAC treatment.

Interleukin-11: A Potential Biomarker and Molecular Therapeutic Target in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) accounts for 85% of lung cancer and is a fast progressive disease when left untreated. Identification of potential biomarkers in NSCLC is an ongoing area of research that aims to detect, diagnose, and prognosticate patients early to optimize treatment. We review the role of interleukin-11 (IL11), a stromal-cell derived pleiotropic cytokine with profibrotic and cellular remodeling properties, as a potential biomarker in NSCLC. This review identifies the need for biomarkers in NSCLC, the potential sources of IL11, and summarizes the available information leveraging upon published literature, publicly available datasets, and online tools. We identify accumulating evidence suggesting IL11 to be a potential biomarker in NSCLC patients. Further in-depth studies into the pathophysiological effects of IL11 on stromal-tumor interaction in NSCLC are warranted and current available literature highlights the potential value of IL11 detection as a diagnostic and prognostic biomarker in NSCLC.

TRPC1 channels regulate the activation of pancreatic stellate cells through ERK1/2 and SMAD2 pathways and perpetuate their pressure-mediated activation

Pancreatic stellate cell (PSC) activation is a major event occurring during pancreatic ductal adenocarcinoma (PDAC) development. Up to now mechanisms underlying their activation by mechanical cues such as the elevated tissue pressure in PDAC remain poorly understood. Here we investigate the role of one potential mechano-transducer, TRPC1 ion channel, in PSC activation. Using pre-activated human siTRPC1 and murine TRPC1-KO PSCs, we show that TRPC1 promotes αSMA (α-smooth muscle actin) expression, the main activation marker, in cooperation with the phosphorylated SMAD2, under normal and elevated pressure. Functional studies following TRPC1 silencing demonstrate the dual role of TRPC1 in the modulation of PSC proliferation and IL-6 secretion through the activation of ERK1/2 and SMAD2 pathways. Moreover, pressurization changes the mechanical behavior of PSCs by increasing their cellular stiffness and emitted traction forces in a TRPC1-dependent manner. In summary, these results point to a role of TRPC1 channels in sensing and transducing the characteristic mechanical properties of the PDAC microenvironment in PSCs.

Circulating Protein Biomarkers for Prognostic Use in Patients with Advanced Pancreatic Ductal Adenocarcinoma Undergoing Chemotherapy

Patients with advanced pancreatic ductal adenocarcinoma (PDAC) have a dismal prognosis. We aimed to find a prognostic protein signature for overall survival (OS) in patients with advanced PDAC, and to explore whether early changes in circulating-protein levels could predict survival. We investigated 92 proteins using the Olink Immuno-Oncology panel in serum samples from 363 patients with advanced PDAC. Protein panels for several survival cut-offs were developed independently by two bioinformaticians using LASSO and Ridge regression models. Two panels of proteins discriminated patients with OS < 90 days from those with OS > 2 years. Index I (CSF-1, IL-6, PDCD1, TNFRSF12A, TRAIL, TWEAK, and CA19-9) had AUCs of 0.99 (95% CI: 0.98−1) (discovery cohort) and 0.89 (0.74−1) (replication cohort). For Index II (CXCL13, IL-6, PDCD1, and TNFRSF12A), the corresponding AUCs were 0.97 (0.93−1) and 0.82 (0.68−0.96). Four proteins (ANGPT2, IL-6, IL-10, and TNFRSF12A) were associated with survival across all treatment groups. Longitudinal samples revealed several changes, including four proteins that were also part of the prognostic signatures (CSF-1, CXCL13, IL-6, TNFRSF12A). This study identified two circulating-protein indices with the potential to identify patients with advanced PDAC with very short OS and with long OS.

Current Pathology Model of Pancreatic Cancer

Pancreatic cancer (PC) is one of the most aggressive and lethal malignant neoplasms, ranking in seventh place in the world in terms of the incidence of death, with overall 5-year survival rates still below 10%. The knowledge about PC pathomechanisms is rapidly expanding. Daily reports reveal new aspects of tumor biology, including its molecular and morphological heterogeneity, explain complicated "cross-talk" that happens between the cancer cells and tumor stroma, or the nature of the PC-associated neural remodeling (PANR). Staying up-to-date is hard and crucial at the same time. In this review, we are focusing on a comprehensive summary of PC aspects that are important in pathologic reporting, impact patients' outcomes, and bring meaningful information for clinicians. Finally, we show promising new trends in diagnostic technologies that might bring a difference in PC early diagnosis.

Gp130-Mediated STAT3 Activation Contributes to the Aggressiveness of Pancreatic Cancer through H19 Long Non-Coding RNA Expression

Simple Summary

The signal transducer and activator of transcription 3 (STAT3) activation correlate with the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). We demonstrated that the autocrine/paracrine interleukin-6 (IL-6) or leukemia inhibitory factor (LIF)/glycoprotein 130 (gp130)/STAT3 pathway contributes to the maintenance of stemness features and membrane-type 1 matrix metalloproteinase (MT1-MMP) expression, and modulates transforming growth factor (TGF)-β1/Smad signaling-mediated epithelial-mesenchymal transition (EMT) and invasion through regulation of TGFβ-RII expression in PDAC cancer stem cell (CSC)-like cells. Furthermore, we demonstrated that p-STAT3 acts through the IL-6 or LIF/gp130/STAT3 pathway to access the active promoter region of metastasis-related long non-coding RNA H19 and contribute to its transcription in CSC-like cells. Therefore, the autocrine/paracrine IL-6 or LIF/gp130/STAT3 pathway in PDAC CSC-like cells exhibiting H19 expression is considered to be involved in the aggressiveness of PDAC, and inhibition of the gp130/STAT3 pathway is a promising strategy to target CSCs for the elimination of PDAC (146/150).

Abstract

Signaling pathways involving signal transducer and activator of transcription 3 (STAT3) play key roles in the aggressiveness of pancreatic ductal adenocarcinoma (PDAC), including their tumorigenesis, invasion, and metastasis. Cancer stem cells (CSCs) have been correlated with PDAC aggressiveness, and activation of STAT3 is involved in the regulation of CSC properties. Here, we investigated the involvement of interleukin-6 (IL-6) or the leukemia inhibitory factor (LIF)/glycoprotein 130 (gp130)/STAT3 pathway and their role in pancreatic CSCs. In PDAC CSC-like cells formed by culturing on a low attachment plate, autocrine/paracrine IL-6 or LIF contributes to gp130/STAT3 pathway activation. Using a gp130 inhibitor, we determined that the gp130/STAT3 pathway contributes to the maintenance of stemness features, the expression of membrane-type 1 matrix metalloproteinase (MT1-MMP), and the invasion of PDAC CSC-like cells. The gp130/STAT3 pathway also modulates the transforming growth factor (TGF)-β1/Smad pathway required for epithelial-mesenchymal transition induction through regulation of TGFβ-RII expression in PDAC CSC-like cells. Furthermore, chromatin immunoprecipitation assays revealed that p-STAT3 can access the active promoter region of H19 to influence this metastasis-related long non-coding RNA and contribute to its transcription in PDAC CSC-like cells. Therefore, the autocrine/paracrine IL-6 or LIF/gp130/STAT3 pathway in PDAC CSC-like cells may eventually facilitate invasion and metastasis, two hallmarks of malignancy. We propose that inhibition of the gp130/STAT3 pathway provides a promising strategy for targeting CSCs for the treatment of PDAC.

The Interplay Between Inflammation and Stromal Components in Pancreatic Cancer

Inflammation involves interactions between various immune cells, inflammatory cells, chemokines and cytokines in pancreatic cancer. Cancer cells as well as surrounding stromal and inflammatory cells establish an inflammatory tumor microenvironment (TME). Inflammation is closely associated with immunity. Meanwhile, immune cells are involved in both inflammation and immune response. Tumor-promoting inflammation and tumor-suppressive immunity are two main characteristics of the tumor microenvironment in pancreatic cancer. Yet, the mechanism of inflammation and immune response in pancreatic cancer development is still unclear due to the dual role of some cytokines and the complicated crosstalk between tumor and stromal components in TME. In this review, we outline the principal cytokines and stromal cells in the pancreatic TME that are involved in the tumor-promoting and immunosuppressive effects of inflammation, and discuss the interaction between inflammation and stromal components in pancreatic cancer progression. Moreover, the clinical approaches based on targeting TME in pancreatic cancer are also summarized. Defining the mechanisms of interplay between inflammation and stromal components will be essential for further development of anti-cancer therapies.

Cancer-Associated Fibroblasts in Pancreatic Ductal Adenocarcinoma: An Update on Heterogeneity and Therapeutic Targeting

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related morbidity and mortality in the western world, with limited therapeutic strategies and dismal long-term survival. Cancer-associated fibroblasts (CAFs) are key components of the pancreatic tumor microenvironment, maintaining the extracellular matrix, while also being involved in intricate crosstalk with cancer cells and infiltrating immunocytes. Therefore, they are potential targets for developing therapeutic strategies against PDAC. However, recent studies have demonstrated significant heterogeneity in CAFs with respect to their origins, spatial distribution, and functional phenotypes within the PDAC tumor microenvironment. Therefore, it is imperative to understand and delineate this heterogeneity prior to targeting CAFs for PDAC therapy.

The Role of Toll-like Receptors (TLRs) Mediated Inflammation in Pancreatic Cancer Pathophysiology

Pancreatic cancer (PC) is one of the most lethal forms of cancer, characterized by its aggressiveness and metastatic potential. Despite significant improvements in PC treatment and management, the complexity of the molecular pathways underlying its development has severely limited the available therapeutic opportunities. Toll-like receptors (TLRs) play a pivotal role in inflammation and immune response, as they are involved in pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). Activation of TLRs initiates a signaling cascade, which in turn, leads to the transcription of several genes involved in inflammation and anti-microbial defense. TLRs are also deregulated in several cancers and can be used as prognostic markers and potential targets for cancer-targeted therapy. In this review we discuss the current knowledge about the role of TLRs in PC progression, focusing on the available TLRs-targeting compounds and their possible use in PC therapy.

5-epi-Sinuleptolide from Soft Corals of the Genus Sinularia Exerts Cytotoxic Effects on Pancreatic Cancer Cell Lines via the Inhibition of JAK2/STAT3, AKT, and ERK Activity

Pancreatic ductal adenocarcinoma is one of the most lethal malignancies: more than half of patients are diagnosed with a metastatic disease, which is associated with a five-year survival rate of only 3%. 5-epi-Sinuleptolide, a norditerpene isolated from Sinularia sp., has been demonstrated to possess cytotoxic activity against cancer cells. However, the cytotoxicity against pancreatic cancer cells and the related mechanisms are unknown. The aim of this study was to evaluate the anti-pancreatic cancer potential of 5-epi-sinuleptolide and to elucidate the underlying mechanisms. The inhibitory effects of 5-epi-sinuleptolide treatment on the proliferation of pancreatic cancer cells were determined and the results showed that 5-epi-sinuleptolide treatment inhibited cell proliferation, induced apoptosis and G2/M cell cycle arrest, and suppressed the invasion of pancreatic cancer cells. The results of western blotting further revealed that 5-epi-sinuleptolide could inhibit JAK2/STAT3, AKT, and ERK phosphorylation, which may account for the diverse cytotoxic effects of 5-epi-sinuleptolide. Taken together, our present investigation unveils a new therapeutic and anti-metastatic potential of 5-epi-sinuleptolide for pancreatic cancer treatment.