Stat3/Socs3 activation by IL-6 transsignaling promotes progression of pancreatic intraepithelial neoplasia and development of pancreatic cancer

Practical application of melatonin for pancreas disorders: protective roles against inflammation, malignancy, and dysfunctions

Melatonin, a hormone primarily produced by the pineal gland, exhibits a range of physiological functions that extend beyond its well-known role in regulating circadian rhythms. This hormone influences energy metabolism, modulates insulin sensitivity, and plays a significant role in controlling sleep patterns and food intake. Notably, melatonin is also synthesized in various peripheral organs, including the gastrointestinal system and pancreas, suggesting its function as a local hormone. The presence of melatonin receptors in the pancreas underscores its relevance in pancreatic physiology. Pancreatic disorders, such as diabetes mellitus (DM), pancreatitis, and pancreatic cancer, often stem from inflammatory processes. The majority of these conditions are characterized by dysregulated immune responses and oxidative stress. Melatonin's anti-inflammatory properties are mediated through the inhibition of pro-inflammatory cytokines and the activation of antioxidant enzymes, which help to mitigate cellular damage. Furthermore, melatonin has demonstrated pro-apoptotic effects on cancer cells, promoting cell death in malignant tissues while preserving healthy cells. Thus, melatonin emerges as a multifaceted agent with significant therapeutic potential for pancreatic disorders. Its ability to reduce inflammation and oxidative stress positions it as a promising adjunct therapy for conditions such as diabetes mellitus, pancreatitis, and pancreatic cancer. By modulating immune responses and enhancing cellular resilience through antioxidant mechanisms, melatonin not only addresses the symptoms but also targets the underlying pathophysiological processes associated with these disorders. This review aims to categorize and summarize the impacts of melatonin on pancreatic functions and disorders, emphasizing its potential as a therapeutic agent for managing pancreatic dysfunctions. Future research should focus on elucidating the precise mechanisms by which melatonin exerts its protective effects on pancreatic tissues and exploring optimal dosing strategies for clinical applications. The integration of melatonin into treatment regimens may enhance existing therapies and offer new hope for individuals suffering from pancreatic dysfunctions.

Inflammation, microbiota, and pancreatic cancer

Pancreatic cancer (PC) is a malignancy of gastrointestinal tract threatening the life of people around the world. In spite of the advances in the treatment of PC, the overall survival of this disease in advanced stage is less than 12%. Moreover, PC cells have aggressive behaviour in proliferation and metastasis as well as capable of developing therapy resistance. Therefore, highlighting the underlying molecular mechanisms in PC pathogenesis can provide new insights for its treatment. In the present review, inflammation and related pathways as well as role of gut microbiome in the regulation of PC pathogenesis are highlighted. The various kinds of interleukins and chemokines are able to regulate angiogenesis, metastasis, proliferation, inflammation and therapy resistance in PC cells. Furthermore, a number of molecular pathways including NF-κB, TLRs and TGF-β demonstrate dysregulation in PC aggravating inflammation and tumorigenesis. Therapeutic regulation of these pathways can reverse inflammation and progression of PC. Both chronic and acute pancreatitis have been shown to be risk factors in the development of PC, further highlighting the role of inflammation. Finally, the composition of gut microbiota can be a risk factor for PC development through affecting pathways such as NF-κB to mediate inflammation.

Immunotherapeutic effects of de novo benzimidazole derivative and prebiotic bacterial levan against triple-negative breast tumors by harnessing the immune landscape to intercept the oncogenic transcriptome

The current study aimed to investigate the therapeutic potential of a novel benzimidazole derivative (BMPE) and a prebiotic bacterial levan (LevAE) against triple-negative breast cancer (TNBC) in a 4T1-cell syngeneic mouse model and to elucidate the immunological and molecular mechanisms underlying the phenotypic changes observed in treated tumors. The metastatic TNBC model was successfully established by subcutaneous inoculation of 100 μL of 4T1 cell suspension (~6000 cells) in the mammary glands of adult female BALB/c mice after brief immunosuppression one day before cell implantation. The therapeutic efficacy of BMPE and LevAE was biochemically, immunologically, and immunohistochemically evaluated. Both compounds exhibited significant antitumor and antimetastatic effects through modulating the tumoral and systemic immune milieus and restoring the TME redox status, which ultimately suppressed the oncogenic transcriptome in the treated breast tumors. Compared to the reference drug (Doxorubicin), BMPE treatment resulted in nearly complete remission within 21 days of treatment, whereas LevAE was less convenient but produced a significant curative outcome. In light of these findings, BMPE and LevAE provide new paradigms for cancer immunotherapy.

Neutrophil extracellular DNA traps activate the TLR9 signaling pathway of pancreatic ductal epithelial cells in patients with type 2 autoimmune pancreatitis

The presence of neutrophil infiltration around the pancreatic ducts has been found to be associated with type 2 autoimmune pancreatitis (AIP). However, the functional role and clinical significance of neutrophil migration in the progression of pancreatitis is not fully understood. Here, we found that neutrophil extracellular traps (NETs) are abundant around the pancreatic duct in patients with type 2 AIP. We also observed an increased expression of toll-like receptor 9 (TLR9) in pancreatic ductal epithelial cells (HPDEC) in type 2 AIP patients compared to other pancreatic diseases. TLR9 acts as the DNA component of NETs (NET-DNA) receptor in HPDEC, which senses extracellular DNA and subsequently activates the NF-κB pathway to promote neutrophil recruitment and induce NET formation. In addition, our results indicated that the hydroxychloroquine (HCQ), acting as a TLR9 antagonist, could effectively inhibit the activation of inflammatory pathways, reduce neutrophil migration and block the positive feedback loop. The intervention positions HCQ acts as a potential target drug for the clinical treatment of type 2 AIP.

Dual efficacy of tocilizumab in managing PD-1 inhibitors-induced myocardial inflammatory injury and suppressing tumor growth with PD-1 inhibitors: a preclinical study

The combined use of tocilizumab (TCZ) and immune checkpoint inhibitors (ICIs) in cancer treatment is gaining attention, but preclinical studies are lacking. Our study aims to investigate the synergistic anti-tumor effect of TCZ combined with ICIs and its role in treating immune-related adverse events (irAEs). The clinical significance of high interleukin-6 (IL-6) expression in tumor patients was analyzed from the Cancer Genome Atlas (TCGA) database. The expression levels of IL-6 were compared before and during the onset of ICIs-associated myocarditis patients. ICIs-related myocardial inflammatory injury and therapeutic lung cancer models were constructed in C57BL/6 J mice using murine-derived programmed death-1 (PD-1) inhibitors alone or in combination with TCZ. Possible inflammatory mechanisms were proposed and validated. The anti-tumor effects and mechanisms of both drugs in combination were assessed. Patients with high IL-6 expression had a poor prognosis, and those with ICIs-associated myocarditis exhibited elevated IL-6 from baseline. In the PD-1 inhibitors-associated myocardial inflammatory injury mouse model, the levels of IL-6 in the blood and cardiac tissues were significantly elevated. TCZ ameliorated immune myocardial inflammatory injury by inhibiting the IL-6/janus kinase 2 (JAK2)/signal transducer and activator of the transcription 3 (STAT3) pathway. The group treated with PD-1 inhibitors combined with TCZ showed significantly slower tumor growth than that treated with PD-1 inhibitors alone. TCZ resisted tumor growth by inhibiting the IL-6-JAK2-STAT3 pathway. By targeting the IL-6-JAK2-STAT3 pathway, TCZ can alleviate PD-1 inhibitors-associated myocardial inflammatory injury mediated by M1-polarized macrophages and plays a synergistic anti-tumor role by inhibiting lung cancer cell proliferation.

Plasticity and Tumor Microenvironment in Pancreatic Cancer: Genetic, Metabolic, and Immune Perspectives

Cancer has long been believed to be a genetic disease caused by the accumulation of mutations in key genes involved in cellular processes. However, recent advances in sequencing technology have demonstrated that cells with cancer driver mutations are also present in normal tissues in response to aging, environmental damage, and chronic inflammation, suggesting that not only intrinsic factors within cancer cells, but also environmental alterations are important key factors in cancer development and progression. Pancreatic cancer tissue is mostly comprised of stromal cells and immune cells. The desmoplasmic microenvironment characteristic of pancreatic cancer is hypoxic and hypotrophic. Pancreatic cancer cells may adapt to this environment by rewiring their metabolism through epigenomic changes, enhancing intrinsic plasticity, creating an acidic and immunosuppressive tumor microenvironment, and inducing noncancerous cells to become tumor-promoting. In addition, pancreatic cancer has often metastasized to local and distant sites by the time of diagnosis, suggesting that a similar mechanism is operating from the precancerous stage. Here, we review key recent findings on how pancreatic cancers acquire plasticity, undergo metabolic reprogramming, and promote immunosuppressive microenvironment formation during their evolution. Furthermore, we present the following two signaling pathways that we have identified: one based on the small G-protein ARF6 driven by KRAS/TP53 mutations, and the other based on the RNA-binding protein Arid5a mediated by inflammatory cytokines, which promote both metabolic reprogramming and immune evasion in pancreatic cancer. Finally, the striking diversity among pancreatic cancers in the relative importance of mutational burden and the tumor microenvironment, their clinical relevance, and the potential for novel therapeutic strategies will be discussed.

A review of the last decade: pancreatic cancer and type 2 diabetes

Pancreatic cancer (PC) is a prevalent gastrointestinal tumour known for its high degree of malignancy, resulting in a mere 10% five-year survival rate for most patients. Over the past decade, a growing body of research has shed light on the intricate bidirectional association between PC and Type 2 diabetes (T2DM). The collection of PC- and T2DM-related articles is derived from two comprehensive databases, namely WOS (Web of Science Core Collection) and CNKI (China National Knowledge Infrastructure). This article discusses the last 10 years of research trends in PC and T2DM and explores their potential regulatory relationship as well as related medications.

Role of Interleukins in Pancreatic Cancer: A Literature Review

PURPOSE

This review article summarizes the pathophysiological aspects of interleukins (ILs) including IL-1, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, and IL-10 in pancreatic cancer (PC).

METHODS

Science Direct, PubMed, and Google Scholar were used for the literature review. The search was conducted until August 12, 2024, and particular keywords such as "Pancreatic Cancer," "Interleukins," "Pathophysiological Aspects," "Immunosuppression," "Invasiveness," and "Metastasis" were used. Focusing on interleukins related to pancreatic cancer, 61 original studies were included: 32 studies for human patients, 16 studies for animal models, and 13 studies for both animal models and human patients. All types of PC were considered. The timeframe of 1991 to 2024 was chosen for clinical studies.

RESULTS

In epithelial pancreatic tumors, IL-1 is a major inflammation factor. Serum concentrations of soluble interleukin-2-receptor were considerably greater in patients with PC and chronic pancreatitis than in healthy individuals. In comparison to controls, pancreatic cancer patients had considerably greater levels of macrophage colony-stimulating factor and significantly lower levels of stem cell factor and IL-3. The tissues and cells of pancreatic cancer have higher concentrations of IL-4 receptors. IL-5 has a role in the accumulation of pancreatic fibrosis. For individuals with pancreatic ductal adenocarcinoma (PDAC), a high serum level of IL-6 may be a separate risk factor for the development of widespread liver metastases. PDAC patients' peripheral blood mononuclear cells exhibit a substantial upregulation of IL-7 receptor. The role of IL-8 in the growth and spread of PC in humans. The miR-200a/β-catenin axis may be the mechanism by which IL-9 stimulates the proliferation and metastasis of PC cells. Blocking IL-10 in the local microenvironment appears to result in a significant reversal of tumor-induced immunosuppression.

CONCLUSION

The article concludes that interleukins 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 played significant roles in the pathogenesis of PC.

Unravelling the druggability and immunological roles of the SOCS-family proteins

The Suppressor of Cytokine Signalling (SOCS) protein family play a critical role in cytokine signalling and regulation of the JAK/STAT pathway with functional consequences to the immune response. Members of this family are implicated in multiple different signalling cascades that drive autoimmune diseases and cancer, through their binding to phosphotyrosine modified proteins as well as ubiquitination activity as part of Cullin5 RING E3 ligases. Here we review the SOCS family members CISH and SOCS1-SOCS7, with a focus on their complex role in immunity. The interactome and signalling network of this protein family is discussed, and the intricate mechanisms through which SOCS proteins alter and manage the immune system are assessed. We offer structural insights into how SOCS proteins engage their interacting partners and native substrates at the protein-protein interaction level. We describe how this knowledge has enabled drug discovery efforts on SOCS proteins to date and propose strategies for therapeutic intervention using small molecules, either via direct inhibition or leveraging their E3 ligase activity for targeted protein degradation.

Inflammatory Processes: Key Mediators of Oncogenesis and Progression in Pancreatic Ductal Adenocarcinoma (PDAC)

Associations between inflammation and cancer were first discovered approximately 160 years ago by Rudolf Virchow, who observed that tumors were infiltrated with inflammatory cells, and defined inflammation as a pathological condition. Inflammation has now emerged as one of the key mediators in oncogenesis and tumor progression, including pancreatic ductal adenocarcinoma (PDAC). However, the role of inflammatory processes in cancers is complicated and controversial, and the detailed regulatory mechanisms are still unclear. This review elucidates the dynamic interplay between inflammation and immune regulation, microenvironment alteration, metabolic reprogramming, and microbiome risk factors in PDAC, committing to exploring a deeper understanding of the role of crucial inflammatory pathways and molecules for providing insights into therapeutic strategies.

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.

Safety and efficacy of itacitinib, a selective JAK1 inhibitor, in advanced hepatocellular cancer: Phase 1b trial (JAKAL)

Overactivation of the JAK/STAT pathway is one of the drivers for the pathophysiology of hepatocellular carcinoma (HCC). We propose a Phase Ib study to evaluate the safety and efficacy of itacitinib, a selective JAK1 inhibitor, as a second-line treatment for patients with advanced or metastatic HCC.Twenty-five patients will receive 400 mg itacitinib orally daily, 28-day cycle. Safety will be reviewed prior to each cycle. Tumor response assessed every 2 months until disease progression, death or withdrawal. Tumor biopsies and blood samples will be taken for presence of JAK1 mutations.Activation of JAK/STAT pathway drives HCC development and is associated with immunotherapy resistance. Itacitinib is hypothesized to be safe and effective in HCC patients that have progressed after first-line therapies.Clinical Trial Registration: EudraCT: 2017-004437-81 NCT04358185 (ClinicalTrials.gov).

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.

A Narrative Review: Immunometabolic Interactions of Host-Gut Microbiota and Botanical Active Ingredients in Gastrointestinal Cancers

The gastrointestinal tract is where the majority of gut microbiota settles; therefore, the composition of the gut microbiota and the changes in metabolites, as well as their modulatory effects on the immune system, have a very important impact on the development of gastrointestinal diseases. The purpose of this article was to review the role of the gut microbiota in the host environment and immunometabolic system and to summarize the beneficial effects of botanical active ingredients on gastrointestinal cancer, so as to provide prospective insights for the prevention and treatment of gastrointestinal diseases. A literature search was performed on the PubMed database with the keywords "gastrointestinal cancer", "gut microbiota", "immunometabolism", "SCFAs", "bile acids", "polyamines", "tryptophan", "bacteriocins", "immune cells", "energy metabolism", "polyphenols", "polysaccharides", "alkaloids", and "triterpenes". The changes in the composition of the gut microbiota influenced gastrointestinal disorders, whereas their metabolites, such as SCFAs, bacteriocins, and botanical metabolites, could impede gastrointestinal cancers and polyamine-, tryptophan-, and bile acid-induced carcinogenic mechanisms. GPRCs, HDACs, FXRs, and AHRs were important receptor signals for the gut microbial metabolites in influencing the development of gastrointestinal cancer. Botanical active ingredients exerted positive effects on gastrointestinal cancer by influencing the composition of gut microbes and modulating immune metabolism. Gastrointestinal cancer could be ameliorated by altering the gut microbial environment, administering botanical active ingredients for treatment, and stimulating or blocking the immune metabolism signaling molecules. Despite extensive and growing research on the microbiota, it appeared to represent more of an indicator of the gut health status associated with adequate fiber intake than an autonomous causative factor in the prevention of gastrointestinal diseases. This study detailed the pathogenesis of gastrointestinal cancers and the botanical active ingredients used for their treatment in the hope of providing inspiration for research into simpler, safer, and more effective treatment pathways or therapeutic agents in the field.

MYC and KRAS cooperation: from historical challenges to therapeutic opportunities in cancer

RAS and MYC rank amongst the most commonly altered oncogenes in cancer, with RAS being the most frequently mutated and MYC the most amplified. The cooperative interplay between RAS and MYC constitutes a complex and multifaceted phenomenon, profoundly influencing tumor development. Together and individually, these two oncogenes regulate most, if not all, hallmarks of cancer, including cell death escape, replicative immortality, tumor-associated angiogenesis, cell invasion and metastasis, metabolic adaptation, and immune evasion. Due to their frequent alteration and role in tumorigenesis, MYC and RAS emerge as highly appealing targets in cancer therapy. However, due to their complex nature, both oncogenes have been long considered "undruggable" and, until recently, no drugs directly targeting them had reached the clinic. This review aims to shed light on their complex partnership, with special attention to their active collaboration in fostering an immunosuppressive milieu and driving immunotherapeutic resistance in cancer. Within this review, we also present an update on the different inhibitors targeting RAS and MYC currently undergoing clinical trials, along with their clinical outcomes and the different combination strategies being explored to overcome drug resistance. This recent clinical development suggests a paradigm shift in the long-standing belief of RAS and MYC "undruggability", hinting at a new era in their therapeutic targeting.

B7 homolog 3 in pancreatic cancer

Despite advances in cancer treatment, pancreatic cancer (PC) remains a disease with high mortality rates and poor survival outcomes. The B7 homolog 3 (B7-H3) checkpoint molecule is overexpressed among many malignant tumors, including PC, with low or absent expression in healthy tissues. By modulating various immunological and nonimmunological molecular mechanisms, B7-H3 may influence the progression of PC. However, the impact of B7-H3 on the survival of patients with PC remains a subject of debate. Still, most available scientific data recognize this molecule as a suppressive factor to antitumor immunity in PC. Furthermore, it has been demonstrated that B7-H3 stimulates the migration, invasion, and metastasis of PC cells, and enhances resistance to chemotherapy. In preclinical models of PC, B7-H3-targeting monoclonal antibodies have exerted profound antitumor effects by increasing natural killer cell-mediated antibody-dependent cellular cytotoxicity and delivering radioisotopes and cytotoxic drugs to the tumor site. Finally, PC treatment with B7-H3-targeting antibody-drug conjugates and chimeric antigen receptor T cells is being tested in clinical studies. This review provides a comprehensive analysis of all PC-related studies in the context of B7-H3 and points to deficiencies in the current data that should be overcome by future research.

STAT3 Increases CVB3 Replication and Acute Pancreatitis and Myocarditis Pathology via Impeding Nuclear Translocation of STAT1 and Interferon-Stimulated Gene Expression

Acute pancreatitis (AP) is an inflammatory disease initiated by the death of exocrine acinar cells, but its pathogenesis remains unclear. Signal transducer and activator of transcription 3 (STAT3) is a multifunctional factor that regulates immunity and the inflammatory response. The protective role of STAT3 is reported in Coxsackievirus B3 (CVB3)-induced cardiac fibrosis, yet the exact role of STAT3 in modulating viral-induced STAT1 activation and type I interferon (IFN)-stimulated gene (ISG) transcription in the pancreas remains unclarified. In this study, we tested whether STAT3 regulated viral-induced STAT1 translocation. We found that CVB3, particularly capsid VP1 protein, markedly upregulated the phosphorylation and nuclear import of STAT3 (p-STAT3) while it significantly impeded the nuclear translocation of p-STAT1 in the pancreases and hearts of mice on day 3 postinfection (p.i.). Immunoblotting and an immunofluorescent assay demonstrated the increased expression and nuclear translocation of p-STAT3 but a blunted p-STAT1 nuclear translocation in CVB3-infected acinar 266-6 cells. STAT3 shRNA knockdown or STAT3 inhibitors reduced viral replication via the rescue of STAT1 nuclear translocation and increasing the ISRE activity and ISG transcription in vitro. The knockdown of STAT1 blocked the antiviral effect of the STAT3 inhibitor. STAT3 inhibits STAT1 activation by virally inducing a potent inhibitor of IFN signaling, the suppressor of cytokine signaling-3 ((SOCS)-3). Sustained pSTAT1 and the elevated expression of ISGs were induced in SOCS3 knockdown cells. The in vivo administration of HJC0152, a pharmaceutical STAT3 inhibitor, mitigated the viral-induced AP and myocarditis pathology via increasing the IFNβ as well as ISG expression on day 3 p.i. and reducing the viral load in multi-organs. These findings define STAT3 as a negative regulator of the type I IFN response via impeding the nuclear STAT1 translocation that otherwise triggers ISG induction in infected pancreases and hearts. Our findings identify STAT3 as an antagonizing factor of the IFN-STAT1 signaling pathway and provide a potential therapeutic target for viral-induced AP and myocarditis.

Precision Targeting Strategies in Pancreatic Cancer: The Role of Tumor Microenvironment

Pancreatic cancer demonstrates an ever-increasing incidence over the last years and represents one of the top causes of cancer-associated mortality. Cells of the tumor microenvironment (TME) interact with cancer cells in pancreatic ductal adenocarcinoma (PDAC) tumors to preserve cancer cells' metabolism, inhibit drug delivery, enhance immune suppression mechanisms and finally develop resistance to chemotherapy and immunotherapy. New strategies target TME genetic alterations and specific pathways in cell populations of the TME. Complex molecular interactions develop between PDAC cells and TME cell populations including cancer-associated fibroblasts, myeloid-derived suppressor cells, pancreatic stellate cells, tumor-associated macrophages, tumor-associated neutrophils, and regulatory T cells. In the present review, we aim to fully explore the molecular landscape of the pancreatic cancer TME cell populations and discuss current TME targeting strategies to provide thoughts for further research and preclinical testing.

Neutrophils in pancreatic ductal adenocarcinoma: bridging preclinical insights to clinical prospects for improved therapeutic strategies

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy characterized by a dismal five-year survival rate of less than 10%. Neutrophils are key components of the innate immune system, playing a pivotal role in the PDAC immune microenvironment.

AREAS COVERED

This review provides a comprehensive survey of the pivotal involvement of neutrophils in the tumorigenesis and progression of PDAC. Furthermore, it synthesizes preclinical and clinical explorations aimed at targeting neutrophils within the milieu of PDAC, subsequently proposing a conceptual framework to propel further inquiry focused on enhancing the therapeutic efficacy of PDAC through neutrophil-targeted strategies. PubMed and Web of Science databases were utilized for researching neutrophils in pancreatic cancer publications prior to 2024.

EXPERT OPINION

Neutrophils play roles in promoting tumor growth and metastasis in PDAC and are associated with poor prognosis. However, the heterogeneity and plasticity of neutrophils and their complex relationships with other immune cells and extracellular matrix also provide new insights for immunotherapy targeting neutrophils to achieve a better prognosis for PDAC.

Focus on Pancreatic Cancer Microenvironment

Pancreatic ductal adenocarcinoma remains one of the most lethal solid tumors due to its local aggressiveness and metastatic potential, with a 5-year survival rate of only 13%. A robust connection between pancreatic cancer microenvironment and tumor progression exists, as well as resistance to current anticancer treatments. Pancreatic cancer has a complex tumor microenvironment, characterized by an intricate crosstalk between cancer cells, cancer-associated fibroblasts and immune cells. The complex composition of the tumor microenvironment is also reflected in the diversity of its acellular components, such as the extracellular matrix, cytokines, growth factors and secreted ligands involved in signaling pathways. Desmoplasia, the hallmark of the pancreatic cancer microenvironment, contributes by creating a dense and hypoxic environment that promotes further tumorigenesis, provides innate systemic resistance and suppresses anti-tumor immune invasion. We discuss the complex crosstalk among tumor microenvironment components and explore therapeutic strategies and opportunities in pancreatic cancer research. Better understanding of the tumor microenvironment and its influence on pancreatic cancer progression could lead to potential novel therapeutic options, such as integration of immunotherapy and cytokine-targeted treatments.

Interleukin-6 serves as a critical factor in various cancer progression and therapy

Interleukin-6 (IL-6), a pro-inflammatory cytokine, plays a crucial role in host immune defense and acute stress responses. Moreover, it modulates various cellular processes, including proliferation, apoptosis, angiogenesis, and differentiation. These effects are facilitated by various signaling pathways, particularly the signal transducer and activator of transcription 3 (STAT3) and Janus kinase 2 (JAK2). However, excessive IL-6 production and dysregulated signaling are associated with various cancers, promoting tumorigenesis by influencing all cancer hallmarks, such as apoptosis, survival, proliferation, angiogenesis, invasiveness, metastasis, and notably, metabolism. Emerging evidence indicates that selective inhibition of the IL-6 signaling pathway yields therapeutic benefits across diverse malignancies, such as multiple myeloma, prostate, colorectal, renal, ovarian, and lung cancers. Targeting key components of IL-6 signaling, such as IL-6Rs, gp130, STAT3, and JAK via monoclonal antibodies (mAbs) or small molecules, is a heavily researched approach in preclinical cancer studies. The purpose of this study is to offer an overview of the role of IL-6 and its signaling pathway in various cancer types. Furthermore, we discussed current preclinical and clinical studies focusing on targeting IL-6 signaling as a therapeutic strategy for various types of cancer.

An oncogenic enhancer promotes melanoma progression via regulating ETV4 expression

BACKGROUND

Enhancers are important gene regulatory elements that promote the expression of critical genes in development and disease. Aberrant enhancer can modulate cancer risk and activate oncogenes that lead to the occurrence of various cancers. However, the underlying mechanism of most enhancers in cancer remains unclear. Here, we aim to explore the function and mechanism of a crucial enhancer in melanoma.

METHODS

Multi-omics data were applied to identify an enhancer (enh17) involved in melanoma progression. To evaluate the function of enh17, CRISPR/Cas9 technology were applied to knockout enh17 in melanoma cell line A375. RNA-seq, ChIP-seq and Hi-C data analysis integrated with luciferase reporter assay were performed to identify the potential target gene of enh17. Functional experiments were conducted to further validate the function of the target gene ETV4. Multi-omics data integrated with CUT&Tag sequencing were performed to validate the binding profile of the inferred transcription factor STAT3.

RESULTS

An enhancer, named enh17 here, was found to be aberrantly activated and involved in melanoma progression. CRISPR/Cas9-mediated deletion of enh17 inhibited cell proliferation, migration, and tumor growth of melanoma both in vitro and in vivo. Mechanistically, we identified ETV4 as a target gene regulated by enh17, and functional experiments further support ETV4 as a target gene that is involved in cancer-associated phenotypes. In addition, STAT3 acts as a transcription factor binding with enh17 to regulate the transcription of ETV4.

CONCLUSIONS

Our findings revealed that enh17 plays an oncogenic role and promotes tumor progression in melanoma, and its transcriptional regulatory mechanisms were fully elucidated, which may open a promising window for melanoma prevention and treatment.

Interleukin-6 classic and trans-signaling utilize glucose metabolism reprogramming to achieve anti- or pro-inflammatory effects

Interleukin (IL)-6 has anti- and pro-inflammatory functions, controlled by IL-6 classic and trans-signaling, respectively. Differences in the downstream signaling mechanism between IL-6 classic and trans-signaling have not been identified. Here, we report that IL-6 activates glycolysis to regulate the inflammatory response. IL-6 regulates glucose metabolism by forming a complex containing signal-transducing activators of transcription 3 (STAT3), hexokinase 2 (HK2), and voltage-dependent anion channel 1 (VDAC1). The IL-6 classic signaling directs glucose flux to oxidative phosphorylation (OxPhos), while IL-6 trans-signaling directs glucose flux to anaerobic glycolysis. Classic IL-6 signaling promotes STAT3 translocation into mitochondria to interact with pyruvate dehydrogenase kinase-1 (PDK1), leading to pyruvate dehydrogenase α (PDHA) dissociation from PDK1. As a result, PDHA is dephosphorylated, and STAT3 is phosphorylated at Ser727. By contrast, IL-6 trans-signaling promotes the interaction of sirtuin 2 (SIRT2) and lactate dehydrogenase A (LDHA), leading to the dissociation of STAT3 from SIRT2. As a result, LDHA is deacetylated, and STAT3 is acetylated and phosphorylated at Tyr705. IL-6 classic signaling promotes the differentiation of regulatory T cells via the PDK1/STAT3/PDHA axis, whereas IL-6 trans-signaling promotes the differentiation of Th17 cells via the SIRT2/STAT3/LDHA axis. Conclusion: IL-6 classic signaling generates anti-inflammatory functions by shifting energy metabolism to OxPhos, while IL-6 trans-signaling generates pro-inflammatory functions by shifting energy metabolism to anaerobic glycolysis.

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.

NEMO/NF-κB signaling functions as a double-edged sword in PanIN formation versus progression to pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is marked by a dismal survival rate, lacking effective therapeutics due to its aggressive growth, late-stage diagnosis, and chemotherapy resistance. Despite debates on NF-κB targeting for PDAC treatment, no successful approach has emerged.

METHODS

To elucidate the role of NF-κB, we ablated NF-κB essential modulator (NEMO), critical for conventional NF-κB signaling, in the pancreata of mice that develop precancerous lesions (KC mouse model). Secretagogue-induced pancreatitis by cerulein injections was utilized to promote inflammation and accelerate PDAC development.

RESULTS

NEMO deletion reduced fibrosis and inflammation in young KC mice, resulting in fewer pancreatic intraepithelial neoplasias (PanINs) at later stages. Paradoxically, however, NEMO deletion accelerated the progression of these fewer PanINs to PDAC and reduced median lifespan. Further, analysis of tissue microarrays from human PDAC sections highlighted the correlation between reduced NEMO expression in neoplastic cells and poorer prognosis, supporting our observation in mice. Mechanistically, NEMO deletion impeded oncogene-induced senescence (OIS), which is normally active in low-grade PanINs. This blockage resulted in fewer senescence-associated secretory phenotype (SASP) factors, reducing inflammation. However, blocked OIS fostered replication stress and DNA damage accumulation which accelerated PanIN progression to PDAC. Finally, treatment with the DNA damage-inducing reagent etoposide resulted in elevated cell death in NEMO-ablated PDAC cells compared to their NEMO-competent counterparts, indicative of a synthetic lethality paradigm.

CONCLUSIONS

NEMO exhibited both oncogenic and tumor-suppressive properties during PDAC development. Caution is suggested in therapeutic interventions targeting NF-κB, which may be detrimental during PanIN progression but beneficial post-PDAC development.

A temporal perspective for tumor-associated macrophage identities and functions

Cancer is a progressive disease that can develop and evolve over decades, with inflammation playing a central role at each of its stages, from tumor initiation to metastasis. In this context, macrophages represent well-established bridges reciprocally linking inflammation and cancer via an array of diverse functions that have spurred efforts to classify them into subtypes. Here, we discuss the intertwines between macrophages, inflammation, and cancer with an emphasis on temporal dynamics of macrophage diversity and functions in pre-malignancy and cancer. By instilling temporal dynamism into the more static classic view of tumor-associated macrophage biology, we propose a new framework to better contextualize their significance in the inflammatory processes that precede and result from the onset of cancer and shape its evolution.

Small protein blockers of human IL-6 receptor alpha inhibit proliferation and migration of cancer cells

BACKGROUND

Interleukin-6 (IL-6) is a multifunctional cytokine that controls the immune response, and its role has been described in the development of autoimmune diseases. Signaling via its cognate IL-6 receptor (IL-6R) complex is critical in tumor progression and, therefore, IL-6R represents an important therapeutic target.

METHODS

An albumin-binding domain-derived highly complex combinatorial library was used to select IL-6R alpha (IL-6Rα)-targeted small protein binders using ribosome display. Large-scale screening of bacterial lysates of individual clones was performed using ELISA, and their IL-6Rα blocking potential was verified by competition ELISA. The binding of proteins to cells was monitored by flow cytometry and confocal microscopy on HEK293T-transfected cells, and inhibition of signaling function was examined using HEK-Blue IL-6 reporter cells. Protein binding kinetics to living cells was measured by LigandTracer, cell proliferation and toxicity by iCELLigence and Incucyte, cell migration by the scratch wound healing assay, and prediction of binding poses using molecular modeling by docking.

RESULTS

We demonstrated a collection of protein variants called NEF ligands, selected from an albumin-binding domain scaffold-derived combinatorial library, and showed their binding specificity to human IL-6Rα and antagonistic effect in HEK-Blue IL-6 reporter cells. The three most promising NEF108, NEF163, and NEF172 variants inhibited cell proliferation of malignant melanoma (G361 and A2058) and pancreatic (PaTu and MiaPaCa) cancer cells, and suppressed migration of malignant melanoma (A2058), pancreatic carcinoma (PaTu), and glioblastoma (GAMG) cells in vitro. The NEF binders also recognized maturation-induced IL-6Rα expression and interfered with IL-6-induced differentiation in primary human B cells.

CONCLUSION

We report on the generation of small protein blockers of human IL-6Rα using directed evolution. NEF proteins represent a promising class of non-toxic anti-tumor agents with migrastatic potential.

Single-cell RNA sequencing to explore cancer-associated fibroblasts heterogeneity: "Single" vision for "heterogeneous" environment

Cancer-associated fibroblasts (CAFs), a phenotypically and functionally heterogeneous stromal cell, are one of the most important components of the tumour microenvironment. Previous studies have consolidated it as a promising target against cancer. However, variable therapeutic efficacy-both protumor and antitumor effects have been observed not least owing to the strong heterogeneity of CAFs. Over the past 10 years, advances in single-cell RNA sequencing (scRNA-seq) technologies had a dramatic effect on biomedical research, enabling the analysis of single cell transcriptomes with unprecedented resolution and throughput. Specifically, scRNA-seq facilitates our understanding of the complexity and heterogeneity of diverse CAF subtypes. In this review, we discuss the up-to-date knowledge about CAF heterogeneity with a focus on scRNA-seq perspective to investigate the emerging strategies for integrating multimodal single-cell platforms. Furthermore, we summarized the clinical application of scRNA-seq on CAF research. We believe that the comprehensive understanding of the heterogeneity of CAFs form different visions will generate innovative solutions to cancer therapy and achieve clinical applications.

Hourglass, a compass navigating global and regional heterogeneity of pancreatic cancer†

Advances in the digital pathology field have facilitated the characterization of histology samples for both clinical and preclinical research. However, uncovering subtle correlations between bioimaging, clinical and molecular parameters requires extensive statistical analysis. As a user-friendly software, Hourglass, simplifies multiparametric dataset analysis through intuitive data visualization and statistical tools. Systemic analysis of interleukin-6 (IL-6)/pStat3 signaling pathway through Hourglass revealed differences in regional immune cell composition within tumors. Moreover, these regional disparities were partially mediated by sex. Overall, Hourglass simplifies information extraction from complex datasets, resolving overlooked regional and global spatial tumor differences. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Navigating IL-6: From molecular mechanisms to therapeutic breakthroughs

This concise review navigates the intricate realm of Interleukin-6 (IL-6), an important member of the cytokine family. Beginning with an introduction to cytokines, this narrative review unfolds with the historical journey of IL-6, illuminating its evolving significance. A crucial section unravels the three distinct signaling modes employed by IL-6, providing a foundational understanding of its versatile interactions within cellular landscapes. Moving deeper, the review meticulously dissects IL-6's signaling mechanisms, unraveling the complexities of its pleiotropic effects in both physiological responses and pathological conditions. A significant focus is dedicated to the essential role IL-6 plays in inflammatory diseases, offering insights into its associations and implications for various health conditions. The review also takes a therapeutic turn by exploring the emergence of anti-IL-6 monoclonal inhibitors, marking a profound stride in treatment modalities. Diving into the molecular realm, the review explores small molecules as agents for IL-6 inhibition, providing a nuanced perspective on diverse intervention strategies. As the review embarks on the final chapters, it contemplates future aspects, offering glimpses into potential research trajectories and the evolving landscape of IL-6-related studies.

Discovery of the Highly Selective and Potent STAT3 Inhibitor for Pancreatic Cancer Treatment

Signal transducer and activator of transcription 3 (STAT3) is an attractive cancer therapeutic target. Unfortunately, targeting STAT3 with small molecules has proven to be very challenging, and for full activation of STAT3, the cooperative phosphorylation of both tyrosine 705 (Tyr705) and serine 727 (Ser727) is needed. Further, a selective inhibitor of STAT3 dual phosphorylation has not been developed. Here, we identified a low nanomolar potency and highly selective small-molecule STAT3 inhibitor that simultaneously inhibits both STAT3 Tyr705 and Ser727 phosphorylation. YY002 potently inhibited STAT3-dependent tumor cell growth in vitro and achieved potent suppression of tumor growth and metastasis in vivo. More importantly, YY002 exhibited favorable pharmacokinetics, an acceptable safety profile, and superior antitumor efficacy compared to BBI608 (STAT3 inhibitor that has advanced into phase III trials). For the mechanism, YY002 is selectively bound to the STAT3 Src Homology 2 (SH2) domain over other STAT members, which strongly suppressed STAT3 nuclear and mitochondrial functions in STAT3-dependent cells. Collectively, this study suggests the potential of small-molecule STAT3 inhibitors as possible anticancer therapeutic agents.

Targeting KRAS mutations in pancreatic cancer: opportunities for future strategies

Targeting the RAS pathway remains the holy grail of precision oncology. In the case of pancreatic ductal adenocarcinomas (PDAC), 90-92% harbor mutations in the oncogene KRAS, triggering canonical MAPK signaling. The smooth structure of the altered KRAS protein without a binding pocket and its affinity for GTP have, in the past, hampered drug development. The emergence of KRASG12C covalent inhibitors has provided renewed enthusiasm for targeting KRAS. The numerous pathways implicated in RAS activation do, however, lead to the development of early resistance. In addition, the dense stromal niche and immunosuppressive microenvironment dictated by oncogenic KRAS can influence treatment responses, highlighting the need for a combination-based approach. Given that mutations in KRAS occur early in PDAC tumorigenesis, an understanding of its pleiotropic effects is key to progress in this disease. Herein, we review current perspectives on targeting KRAS with a focus on PDAC.

Histone lactylation inhibits RARγ expression in macrophages to promote colorectal tumorigenesis through activation of TRAF6-IL-6-STAT3 signaling

Macrophages are phenotypically and functionally diverse in the tumor microenvironment (TME). However, how to remodel macrophages with a protumor phenotype and how to manipulate them for therapeutic purposes remain to be explored. Here, we show that in the TME, RARγ is downregulated in macrophages, and its expression correlates with poor prognosis in patients with colorectal cancer (CRC). In macrophages, RARγ interacts with tumor necrosis factor receptor-associated factor 6 (TRAF6), which prevents TRAF6 oligomerization and autoubiquitination, leading to inhibition of nuclear factor κB signaling. However, tumor-derived lactate fuels H3K18 lactylation to prohibit RARγ gene transcription in macrophages, consequently enhancing interleukin-6 (IL-6) levels in the TME and endowing macrophages with tumor-promoting functions via activation of signal transducer and activator of transcription 3 (STAT3) signaling in CRC cells. We identified that nordihydroguaiaretic acid (NDGA) exerts effective antitumor action by directly binding to RARγ to inhibit TRAF6-IL-6-STAT3 signaling. This study unravels lactate-driven macrophage function remodeling by inhibition of RARγ expression and highlights NDGA as a candidate compound for treating CRC.

Targeting KRAS and SHP2 signaling pathways for immunomodulation and improving treatment outcomes in solid tumors

Historically, KRAS has been considered 'undruggable' inspite of being one of the most frequently altered oncogenic proteins in solid tumors, primarily due to the paucity of pharmacologically 'druggable' pockets within the mutant isoforms. However, pioneering developments in drug design capable of targeting the mutant KRAS isoforms especially KRASG12C-mutant cancers, have opened the doors for emergence of combination therapies comprising of a plethora of inhibitors targeting different signaling pathways. SHP2 signaling pathway, primarily known for activation of intracellular signaling pathways such as KRAS has come up as a potential target for such combination therapies as it emerged to be the signaling protein connecting KRAS and the immune signaling pathways and providing the link for understanding the overlapping regions of RAS/ERK/MAPK signaling cascade. Thus, SHP2 inhibitors having potent tumoricidal activity as well as role in immunomodulation have generated keen interest in researchers to explore its potential as combination therapy in KRAS mutant solid tumors. However, the excitement with these combination therapies need to overcome challenges thrown up by drug resistance and enhanced toxicity. In this review, we will discuss KRAS and SHP2 signaling pathways and their roles in immunomodulation and regulation of tumor microenvironment and also analyze the positive effects and drawbacks of the different combination therapies targeted at these signaling pathways along with their present and future potential to treat solid tumors.

Innate and adaptive immune-directed tumour microenvironment in pancreatic ductal adenocarcinoma

One of the most deadly and aggressive cancers in the world, pancreatic ductal adenocarcinoma (PDAC), typically manifests at an advanced stage. PDAC is becoming more common, and by the year 2030, it is expected to overtake lung cancer as the second greatest cause of cancer-related death. The poor prognosis can be attributed to a number of factors, including difficulties in early identification, a poor probability of curative radical resection, limited response to chemotherapy and radiotherapy, and its immunotherapy resistance. Furthermore, an extensive desmoplastic stroma that surrounds PDAC forms a mechanical barrier that prevents vascularization and promotes poor immune cell penetration. Phenotypic heterogeneity, drug resistance, and immunosuppressive tumor microenvironment are the main causes of PDAC aggressiveness. There is a complex and dynamic interaction between tumor cells in PDAC with stromal cells within the tumour immune microenvironment. The immune suppressive microenvironment that promotes PDAC aggressiveness is contributed by a range of cellular and humoral factors, which itself are modulated by the cancer. In this review, we describe the role of innate and adaptive immune cells, complex tumor microenvironment in PDAC, humoral factors, innate immune-mediated therapeutic advances, and recent clinical trials in PDAC.

Soluble receptors in cancer: mechanisms, clinical significance, and therapeutic strategies

Soluble receptors are soluble forms of receptors found in the extracellular space. They have emerged as pivotal regulators of cellular signaling and disease pathogenesis. This review emphasizes their significance in cancer as diagnostic/prognostic markers and potential therapeutic targets. We provide an overview of the mechanisms by which soluble receptors are generated along with their functions. By exploring their involvement in cancer progression, metastasis, and immune evasion, we highlight the importance of soluble receptors, particularly soluble cytokine receptors and immune checkpoints, in the tumor microenvironment. Although current research has illustrated the emerging clinical relevance of soluble receptors, their therapeutic applications remain underexplored. As the landscape of cancer treatment evolves, understanding and targeting soluble receptors might pave the way for novel strategies for cancer diagnosis, prognosis, and therapy.

Dynamic IL-6R/STAT3 signaling leads to heterogeneity of metabolic phenotype in pancreatic ductal adenocarcinoma cells

Malignancy is enabled by pro-growth mutations and adequate energy provision. However, global metabolic activation would be self-terminating if it depleted tumor resources. Cancer cells could avoid this by rationing resources, e.g., dynamically switching between "baseline" and "activated" metabolic states. Using single-cell metabolic phenotyping of pancreatic ductal adenocarcinoma cells, we identify MIA-PaCa-2 as having broad heterogeneity of fermentative metabolism. Sorting by a readout of lactic acid permeability separates cells by fermentative and respiratory rates. Contrasting phenotypes persist for 4 days and are unrelated to cell cycling or glycolytic/respiratory gene expression; however, transcriptomics links metabolically active cells with interleukin-6 receptor (IL-6R)-STAT3 signaling. We verify this by IL-6R/STAT3 knockdowns and sorting by IL-6R status. IL-6R/STAT3 activates fermentation and transcription of its inhibitor, SOCS3, resulting in delayed negative feedback that underpins transitions between metabolic states. Among cells manifesting wide metabolic heterogeneity, dynamic IL-6R/STAT3 signaling may allow cell cohorts to take turns in progressing energy-intense processes without depleting shared resources.

Unraveling the complexity of STAT3 in cancer: molecular understanding and drug discovery

Signal transducer and activator of transcription 3 (STAT3) is a transcriptional factor involved in almost all cancer hallmark features including tumor proliferation, metastasis, angiogenesis, immunosuppression, tumor inflammation, metabolism reprogramming, drug resistance, cancer stemness. Therefore, STAT3 has become a promising therapeutic target in a wide range of cancers. This review focuses on the up-to-date knowledge of STAT3 signaling in cancer. We summarize both the positive and negative modulators of STAT3 together with the cancer hallmarks involving activities regulated by STAT3 and highlight its extremely sophisticated regulation on immunosuppression in tumor microenvironment and metabolic reprogramming. Direct and indirect inhibitors of STAT3 in preclinical and clinical studies also have been summarized and discussed. Additionally, we highlight and propose new strategies of targeting STAT3 and STAT3-based combinations with established chemotherapy, targeted therapy, immunotherapy and combination therapy. These efforts may provide new perspectives for STAT3-based target therapy in cancer.

XYA-2: a marine-derived compound targeting apoptosis and multiple signaling pathways in pancreatic cancer

Background

Pancreatic cancer is a highly aggressive and fatal disease with limited treatment options and poor prognosis for patients. This study aimed to investigate the impact of XYA-2 {N-(3,7-dimethyl-2,6-octadienyl)-2-aza-2-deoxychaetoviridin A}, a nitrogenated azaphilon previously reported from a deep-sea-derived fungus on the progression of pancreatic cancer cells.

Methods

The inhibitory effects of XYA-2 on cell proliferation, clonogenic potential, cell cycle progression, apoptosis, migration, and invasion were assessed using various assays. The CCK-8 assay, clone formation assay, flow cytometry assay, wound healing assay, and transwell assay were employed to evaluate cell proliferation, clonogenic potential, cell cycle progression, apoptosis, migration, and invasion, respectively. Moreover, we employed RNA-seq and bioinformatics analyses to uncover the underlying mechanism by which XYA-2 influences pancreatic cancer cells. The revealed mechanism was subsequently validated through qRT-PCR.

Results

Our results demonstrated that XYA-2 dose-dependently inhibited the proliferation of pancreatic cancer cells and induced cell cycle arrest and apoptosis. Additionally, XYA-2 exerted a significant inhibitory effect on the invasion and migration of cancer cells. Moreover, XYA-2 was found to regulate the expression of genes involved in multiple cancer-related pathways based on our RNA-seq and bioinformatics analysis.

Conclusion

These findings highlight the potential of XYA-2 as a promising therapeutic option for the treatment of pancreatic cancer.

Intracellular calcium links milk stasis to lysosome-dependent cell death during early mammary gland involution

Involution of the mammary gland after lactation is a dramatic example of coordinated cell death. Weaning causes distension of the alveolar structures due to the accumulation of milk, which, in turn, activates STAT3 and initiates a caspase-independent but lysosome-dependent cell death (LDCD) pathway. Although the importance of STAT3 and LDCD in early mammary involution is well established, it has not been entirely clear how milk stasis activates STAT3. In this report, we demonstrate that protein levels of the PMCA2 calcium pump are significantly downregulated within 2-4 h of experimental milk stasis. Reductions in PMCA2 expression correlate with an increase in cytoplasmic calcium in vivo as measured by multiphoton intravital imaging of GCaMP6f fluorescence. These events occur concomitant with the appearance of nuclear pSTAT3 expression but prior to significant activation of LDCD or its previously implicated mediators such as LIF, IL6, and TGFβ3, all of which appear to be upregulated by increased intracellular calcium. We further demonstrate that increased intracellular calcium activates STAT3 by inducing degradation of its negative regulator, SOCS3. We also observed that milk stasis, loss of PMCA2 expression and increased intracellular calcium levels activate TFEB, an important regulator of lysosome biogenesis through a process involving inhibition of CDK4/6 and cell cycle progression. In summary, these data suggest that intracellular calcium serves as an important proximal biochemical signal linking milk stasis to STAT3 activation, increased lysosomal biogenesis, and lysosome-mediated cell death.

New aryl-/heteroarylpiperazine derivatives of 1,7-dimethyl-8,9-diphenyl-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5,10-trione: Synthesis and preliminary studies of biological activities

Compounds containing dicarboximide skeleton such as succinimides, maleimides, glutarimides, and phthalimides possess broad biological properties including anti-fungal, antibacterial, antidepressant, or analgesic activities. The piperazine ring is found in a wide range of molecules that have demonstrated a variety of biological functions such as anticancer action and 5-HT receptors agonist/antagonist activity. In the present study, we combined both structures to develop new antitumor agents, a series of piperazine derivatives of 1,7-dimethyl-8,9-diphenyl-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5,10-trione and evaluated their biological activity. The structures of all tested compounds were confirmed by 1H and 13C NMR and by ESI MS spectral analysis. Their cytotoxicity was assessed in vitro against eight human cancer cell lines, namely prostate (PC3), colon (HCT116, SW480, SW620), leukemia (K562), liver (HepG2), lung (A549) and breast (MDA-Mb-231) in contrast to normal HMEC-1 cell line, by using MTT and Trypan blue method. The tested compounds showed significant activity toward cancer cells. The most pronounced cytotoxic effect was observed in K562 and HCT116 with IC50 values below 10 μM for all studied compounds. Importantly, the most promising derivatives for each cancer cell line (IC50 < 10 μM) exerted a weaker cytotoxic effect toward normal HMEC-1 cells than cancer cells. The evaluation of proapoptotic and inhibitory effects on IL-6 release showed that K562 and HCT116 cells were more sensitive to studied compounds than other cancer cell lines. Furthermore, for all piperazine derivatives, the functional activities at the 5-HT1A, D2 receptors as well as their binding affinities at the 5-HT2A, H1 and M receptors, were determined. The current investigation was able to successfully design compounds with both serotoninergic and anticancer properties. It serves as a good starting point for a multimodal approach for the management of cancer and cancer-related symptoms.

Leveraging a KRAS-based signature to predict the prognosis and drug sensitivity of colon cancer and identifying SPINK4 as a new biomarker

KRAS is one of the leading mutations reported in colon cancer. However, there are few studies on the application of KRAS related signature in predicting prognosis and drug sensitivity of colon cancer patient. We identified KRAS related differentially expressed genes (DEGs) using The Cancer Genome Atlas (TCGA) database. A signature closely related to overall survival was recognized with Kaplan-Meier survival analysis and univariate cox regression analysis. Then we validated this signature with overall expression score (OE score) algorithm using both scRNA-seq and bulk RNA-seq data. Based on this signature, we performed LASSO cox regression to establish a prognostic model, and corresponding scores were calculated. Differences in genomic alteration, immune microenvironment, drug sensitivity between high- and low-KRD score groups were investigated. A KRAS related signature composed of 80 DEGs in colon cancer were recognized, among which 19 genes were selected to construct a prognostic model. This KRAS related signature was significantly correlated with worse prognosis. Furthermore, patients who scored lower in the prognostic model presented a higher likelihood of responding to chemotherapy, targeted therapy and immunotherapy. Furthermore, among the 19 selected genes in the model, SPINK4 was identified as an independent prognostic biomarker. Further validation in vitro indicated the knockdown of SPINK4 promoted the proliferation and migration of SW48 cells. In conclusion, a novel KRAS related signature was identified and validated based on clinical and genomic information from TCGA and GEO databases. The signature was proved to regulate genomic alteration, immune microenvironment and drug sensitivity in colon cancer, and thus might serve as a predictor for individual prognosis and treatment.

PKCι induces differential phosphorylation of STAT3 to modify STAT3-related signaling pathways in pancreatic cancer cells

An increasing number of studies have documented atypical protein kinase C isoform ι (PKCι) as an oncoprotein playing multifaceted roles in pancreatic carcinogenesis, including sustaining the transformed growth, prohibiting apoptosis, strengthening invasiveness, facilitating autophagy, as well as promoting the immunosuppressive tumor microenvironment of pancreatic tumors. In this study, we present novel evidence that PKCι overexpression increases STAT3 phosphorylation at the Y705 residue while decreasing STAT3 phosphorylation at the S727 residue in pancreatic cancer cells. We further demonstrate that STAT3 phosphorylation at Y705 and S727 residues is mutually antagonistic, and that STAT3 Y705 phosphorylation is positively related to the transcriptional activity of STAT3 in pancreatic cancer cells. Furthermore, we discover that PKCι inhibition attenuates STAT3 transcriptional activity via Y705 dephosphorylation, which appears to be resulted from enhanced phosphorylation of S727 in pancreatic cancer cells. Finally, we investigate and prove that by modulating the STAT3 activity, the PKCι inhibitor can synergistically enhance the antitumor effects of pharmacological STAT3 inhibitors or reverse the anti-apoptotic side effects incited by the MEK inhibitor, thereby posing as a prospective sensitizer in the treatment of pancreatic cancer cells.

Value of C-Reactive Protein-Triglyceride Glucose Index in Predicting Cancer Mortality in the General Population: Results from National Health and Nutrition Examination Survey

BACKGROUND

Cancer is one of the leading causes of death. The current work aims to investigate the association between C-reactive protein-triglyceride glucose index (CTI) and the risk of incident cancer mortality and to evaluate the usefulness of CTI to refine the risk stratification of cancer mortality.

METHODS

The study enrolled 19,957 subjects from American National Health and Nutrition Examination Survey. CTI was defined as 0.412*Ln(CRP) + ln[T.G. (mg/dL) × FPG (mg/dL)/2]. Cox regression was performed to investigate the association.

RESULTS

During a follow-up of 215417.52 person-years, 736 subjects died due to malignant tumors, and the incidence of cancer mortality was 3.42 per 1,000 person-years. Kaplan-Meier curve revealed that the fourth quartile group had the lowest cancer mortality-free rate (Log-Rank p < 0.001). After full adjustment, each SD increase of CTI cast a 32.7% additional risk of incident cancer mortality. Furthermore, cancer mortality risk elevated proportionally with the increase of CTI. Finally, ROC and reclassification analyses supported the usefulness of CTI in improving the risk stratification of incident cancer mortality.

CONCLUSION

The study revealed a significant association between CTI and cancer mortality risk, suggesting the value of CTI in improving the risk stratification of incident cancer mortality. KEY MESAGESC-reactive protein-triglyceride glucose index (CTI) is positively associated with cancer mortality risk in the general population.The association was linear in the whole range of CTI.CTI could improve the risk prediction of cancer mortality in the general population.

FBXO38 mediates FGL1 ubiquitination and degradation to enhance cancer immunity and suppress inflammation

Upregulation of FGL1 helps tumors escape from immune surveillance, and therapeutic antibodies targeting FGL1 have potential as another immune checkpoint inhibitor. However, the underlying mechanism of high FGL1 protein level in cancers is not well defined. Here, we report that FBXO38 interacts with and ubiquitylates FGL1 to negatively regulate its stability and to mediate cancer immune response. Depletion of FBXO38 markedly augments FGL1 abundance, not only suppressing CD8+ T cell infiltration and enhancing immune evasion of tumor but also increasing inflammation in mice. Importantly, we observe a negative correlation of FBXO38 with FGL1 and IL-6 in non-small cell lung cancer specimens. FGL1 and IL-6 levels positively correlate with TNM (tumor, lymph node, metastasis) stages, while FBXO38 and the infiltrating CD8+ T cells negatively correlate with TNM stages. Our study identifies a mechanism regulating FGL1 stability and a target to enhance the immunotherapy and suggests that the combination of anti-FGL1 and anti-IL-6 is a potential therapeutic strategy for cancer immunotherapy.

Anxiolytics cause anxiety in pancreatic cancer

Benzodiazepines (BZDs) are commonly prescribed for pancreatic cancer patients. To investigate the correlation between BZDs and survival outcomes a recent study by Cornwell et al. found that lorazepam (LOR) correlates with poor survival. The mechanistic study shows that LOR increases interleukin 6 (IL6) expression in cancer-associated fibroblasts via GPR68.

Associations between serum estradiol and IL-6/sIL-6R/sgp130 complex in female patients with major depressive disorder

BACKGROUND

It has been hypothesized that the IL-6/sIL-6R/sgp130 complex, an inflammatory complex, plays a critical role in the pathogenesis of major depressive disorder (MDD). Estradiol (E2) is a sex steroid hormone involved in emotional regulation and MDD. This study aimed to investigate the relationship between E2 and IL-6/sIL-6R/sgp130 complex in patients with MDD.

METHODS

Using enzyme-linked immunosorbent assay, the levels of IL-6, sIL-6Rα, and sgp130 were compared between 117 female patients with MDD and 122 healthy controls.The serum concentrations of E2 and other biomarkers were also measured.

RESULTS

(1) The serum levels of IL-6 and sIL-6Rα in patients with MDD were significantly higher than those in the control group, while the serum levels of sgp130 and E2 were significantly lower (all P < 0.05). (2) Low levels of E2 were associated with high levels of IL-6 and low levels of sgp130 (all P < 0.01). (3) HAMD-24 score was positively correlated with the serum level of IL-6, but negatively correlated with the serum levels of sgp130 and E2(all P < 0.05). (4) IL-6 and sgp130 had certain prognostic values in MDD, and the combination of various indicators showed a significantly superior prognostic value.

CONCLUSIONS

The IL6/sIL-6R/sgp130 complex in female patients with MDD was closely related to E2 level. In addition, IL-6 and sgp130 may be valuable serum biomarkers for the diagnosis and prognosis of MDD in women.

EGFR stimulation enables IL-6 trans-signalling via iRhom2-dependent ADAM17 activation in mammary epithelial cells

The cytokine interleukin-6 (IL-6) has considerable pro-inflammatory properties and is a driver of many physiological and pathophysiological processes. Cellular responses to IL-6 are mediated by membrane-bound or soluble forms of the IL-6 receptor (IL-6R) complexed with the signal-transducing subunit gp130. While expression of the membrane-bound IL-6R is restricted to selected cell types, soluble IL-6R (sIL-6R) enables gp130 engagement on all cells, a process termed IL-6 trans-signalling and considered to be pro-inflammatory. sIL-6R is predominantly generated through proteolytic processing by the metalloproteinase ADAM17. ADAM17 also liberates ligands of the epidermal growth factor receptor (EGFR), which is a prerequisite for EGFR activation and results in stimulation of proliferative signals. Hyperactivation of EGFR mostly due to activating mutations drives cancer development. Here, we reveal an important link between overshooting EGFR signalling and the IL-6 trans-signalling pathway. In epithelial cells, EGFR activity induces not only IL-6 expression but also the proteolytic release of sIL-6R from the cell membrane by increasing ADAM17 surface activity. We find that this derives from the transcriptional upregulation of iRhom2, a crucial regulator of ADAM17 trafficking and activation, upon EGFR engagement, which results in increased surface localization of ADAM17. Also, phosphorylation of the EGFR-downstream mediator ERK mediates ADAM17 activity via interaction with iRhom2. In sum, our study reveals an unforeseen interplay between EGFR activation and IL-6 trans-signalling, which has been shown to be fundamental in inflammation and cancer.

Targeting IL-6 trans-signalling: past, present and future prospects

Interleukin-6 (IL-6) is a key immunomodulatory cytokine that affects the pathogenesis of diverse diseases, including autoimmune diseases, chronic inflammatory conditions and cancer. Classical IL-6 signalling involves the binding of IL-6 to the membrane-bound IL-6 receptor α-subunit (hereafter termed 'mIL-6R') and glycoprotein 130 (gp130) signal-transducing subunit. By contrast, in IL-6 trans-signalling, complexes of IL-6 and the soluble form of IL-6 receptor (sIL-6R) signal via membrane-bound gp130. A third mode of IL-6 signalling - known as cluster signalling - involves preformed complexes of membrane-bound IL-6-mIL-6R on one cell activating gp130 subunits on target cells. Antibodies and small molecules have been developed that block all three forms of IL-6 signalling, but in the past decade, IL-6 trans-signalling has emerged as the predominant pathway by which IL-6 promotes disease pathogenesis. The first selective inhibitor of IL-6 trans-signalling, sgp130, has shown therapeutic potential in various preclinical models of disease and olamkicept, a sgp130Fc variant, had promising results in phase II clinical studies for inflammatory bowel disease. Technological developments have already led to next-generation sgp130 variants with increased affinity and selectivity towards IL-6 trans-signalling, along with indirect strategies to block IL-6 trans-signalling. Here, we summarize our current understanding of the biological outcomes of IL-6-mediated signalling and the potential for targeting this pathway in the clinic.