IL1 Receptor Antagonist Inhibits Pancreatic Cancer Growth by Abrogating NF-κB Activation

Igniting hope: Harnessing NLRP3 inflammasome-GSDMD-mediated pyroptosis for cancer immunotherapy

In the contemporary landscape of oncology, immunotherapy, represented by immune checkpoint blockade (ICB) therapy, stands out as a beacon of innovation in cancer treatment. Despite its promise, the therapy's progression is hindered by suboptimal clinical response rates. Addressing this challenge, the modulation of the NLRP3 inflammasome-GSDMD-mediated pyroptosis pathway holds promise as a means to augment the efficacy of immunotherapy. In the pathway, the NLRP3 inflammasome serves as a pivotal molecular sensor that responds to inflammatory stimuli within the organism. Its activation leads to the release of cytokines interleukin 1β and interleukin 18 through the cleavage of GSDMD, thereby forming membrane pores and potentially resulting in pyroptosis. This cascade of processes exerts a profound impact on tumor development and progression, with its function and expression exhibiting variability across different tumor types and developmental stages. Consequently, understanding the specific roles of the NLRP3 inflammasome and GSDMD-mediated pyroptosis in diverse tumors is imperative for comprehending tumorigenesis and crafting precise therapeutic strategies. This review aims to elucidate the structure and activation mechanisms of the NLRP3 inflammasome, as well as the induction mechanisms of GSDMD-mediated pyroptosis. Additionally, we provide a comprehensive overview of the involvement of this pathway in various cancer types and its applications in tumor immunotherapy, nanotherapy, and other fields. Emphasis is placed on the feasibility of leveraging this approach to enhance ICB therapy within the field of immunotherapy. Furthermore, we discuss the potential applications of this pathway in other immunotherapy methods, such as chimeric antigen receptor T-cell (CAR-T) therapy and tumor vaccines.

Anakinra-Loaded Sphingomyelin Nanosystems Modulate In Vitro IL-1-Dependent Pro-Tumor Inflammation in Pancreatic Cancer

Pancreatic cancer is a very aggressive disease with a dismal prognosis. The tumor microenvironment exerts immunosuppressive activities through the secretion of several cytokines, including interleukin (IL)-1. The IL-1/IL-1 receptor (IL-1R) axis is a key regulator in tumor-promoting T helper (Th)2- and Th17-type inflammation. Th2 cells are differentiated by dendritic cells endowed with Th2-polarizing capability by the thymic stromal lymphopoietin (TSLP) that is secreted by IL-1-activated cancer-associated fibroblasts (CAFs). Th17 cells are differentiated in the presence of IL-1 and other IL-1-regulated cytokines. In pancreatic cancer, the use of a recombinant IL-1R antagonist (IL1RA, anakinra, ANK) in in vitro and in vivo models has shown efficacy in targeting the IL-1/IL-1R pathway. In this study, we have developed sphingomyelin nanosystems (SNs) loaded with ANK (ANK-SNs) to compare their ability to inhibit Th2- and Th17-type inflammation with that of the free drug in vitro. We found that ANK-SNs inhibited TSLP and other pro-tumor cytokines released by CAFs at levels similar to ANK. Importantly, inhibition of IL-17 secretion by Th17 cells, but not of interferon-γ, was significantly higher, and at lower concentrations, with ANK-SNs compared to ANK. Collectively, the use of ANK-SNs might be beneficial in reducing the effective dose of the drug and its toxic effects.

Interleukin-1α as a Potential Prognostic Biomarker in Pancreatic Cancer

PURPOSE

We assessed the prognostic role of pro-inflammatory cytokines of the IL-1 superfamily in patients with pancreatic cancer.

METHODS

This retrospective study was performed using two independent cohorts of patients with pancreatic cancer: the International Cancer Genome Consortium (ICGC, N = 267) cohort and The Cancer Genome Atlas (TCGA, N = 178) cohort. Univariate Cox regressions were used to identify prognosis-related pro-inflammatory cytokines of the IL-1 superfamily. Cytokines associated with outcome were included in a multivariate Cox model with relevant clinicopathological variables to identify prognostic biomarkers.

RESULTS

IL-1α was the only pro-inflammatory cytokine of the IL-1 superfamily that was significantly associated with prognosis in both cohorts. In the training cohort (ICGC), the decile of patients with the lowest IL1A expression had better overall survival (HR = 1.99 [1.01-3.93], p = 0.05) and better relapse-free survival (HR = 1.85 [1.02-3.34], p = 0.04) than the group with the highest IL1A expression. The validation cohort (TCGA) confirmed these results: the decile with the lowest IL1A expression had better overall survival (HR = 3.00 [1.14-7.90], p = 0.03) and a lower risk of progression (HR = 3.11 [1.24-7.80], p = 0.01).

CONCLUSIONS

IL1A is an independent prognostic marker and could be considered a potential therapeutic target in pancreatic cancer patients.

Exosomal lncRNA XIST promotes perineural invasion of pancreatic cancer cells via miR-211-5p/GDNF

Perineural invasion (PNI) is an essential form of tumor metastasis in multiple malignant cancers, such as pancreatic cancer, prostate cancer, and head and neck cancer. Growing evidence has revealed that pancreatic cancer recurrence and neuropathic pain positively correlate with PNI. Therefore, targeting PNI is a proper strategy for pancreatic cancer treatment. Exosomal lncRNA derived from pancreatic cancer cells is an essential component of the tumor microenvironment. However, whether exosomal lncXIST derived from pancreatic cancer cells can promote PNI and its exact mechanism remains to be elucidated. We show that lncXIST mediates nerve-tumor crosstalk via exosomal delivery. Our data reveal that exosomal lncXIST derived from pancreatic cancer cells is delivered to neural cells and promotes their release of glial-cell-line-derived neurotrophic factor (GDNF), essential in facilitating the PNI of pancreatic cancer. Mechanistically, microRNA-211-5p negatively regulates GDNF, and lncXIST serves as a miR-211-5p sponge. The function of exosomes in the dynamic interplay between nerves and cancer is confirmed in both in vivo and in vitro PNI models. Therefore, targeting pancreatic cancer cell-derived exosomal lncXIST may provide clues for a promising approach for developing a new strategy to combat PNI of pancreatic cancer.

The NF-κB/NUAK2 signaling axis regulates pancreatic cancer progression by targeting SMAD2/3

Nuclear factor kappa B (NF-κB) plays a pivotal role in the development of pancreatic cancer, and its phosphorylation has previously been linked to the regulation of NUAK2. However, the regulatory connection between NF-κB and NUAK2, as well as NUAK2's role in pancreatic cancer, remains unclear. In this study, we observed that inhibiting NUAK2 impeded the proliferation, migration, and invasion of pancreatic cancer cells while triggering apoptosis. NUAK2 overexpression partially resisted apoptosis and reversed the inhibitory effects of the NF-κB inhibitor. NF-κB transcriptionally regulated NUAK2 transcription by binding to the promoter region of NUAK2. Mechanistically, NUAK2 knockdown remarkably reduced the expression levels of p-SMAD2/3 and SMAD2/3, resulting in decreased nuclear translocation of SMAD4. In SMAD4-negative cells, NUAK2 knockdown impacted FAK signaling by downregulating SMAD2/3. Moreover, NUAK2 knockdown heightened the sensitivity of pancreatic cancer cells to gemcitabine, suggesting that NUAK2 inhibitors could be a promising strategy for pancreatic cancer treatment.

Targeted Therapy for Highly Desmoplastic and Immunosuppressive Tumor Microenvironment of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with a very poor prognosis. Despite advancements in treatment strategies, PDAC remains recalcitrant to therapies because patients are often diagnosed at an advanced stage. The advanced stage of PDAC is characterized by metastasis, which typically renders it unresectable by surgery or untreatable by chemotherapy. The tumor microenvironment (TME) of PDAC comprises highly proliferative myofibroblast-like cells and hosts the intense deposition of a extracellular matrix component that forms dense fibrous connective tissue, a process called the desmoplastic reaction. In desmoplastic TMEs, the incessant aberration of signaling pathways contributes to immunosuppression by suppressing antitumor immunity. This feature offers a protective barrier that impedes the targeted delivery of drugs. In addition, the efficacy of immunotherapy is compromised because of the immune cold TME of PDAC. Targeted therapy approaches towards stromal and immunosuppressive TMEs are challenging. In this review, we discuss cellular and non-cellular TME components that contain actionable targets for drug development. We also highlight findings from preclinical studies and provide updates about the efficacies of new investigational drugs in clinical trials.

Interleukin-1 receptor antagonist: An alternative therapy for cancer treatment

The interleukin-1 receptor antagonist (IL-1Ra) is an anti-inflammatory cytokine and a naturally occurring antagonist of the IL-1 receptor. It effectively counteracts the IL-1 signaling pathway mediated by IL-1α/β. Over the past few decades, accumulating evidence has suggested that IL-1 signaling plays an essential role in tumor formation, growth, and metastasis. Significantly, anakinra, the first United States Food and Drug Administration (FDA)-approved IL-1Ra drug, has demonstrated promising antitumor effects in animal studies. Numerous clinical trials have subsequently incorporated anakinra into their cancer treatment protocols. In this review, we comprehensively discuss the research progress on the role of IL-1 in tumors and summarize the significant contribution of IL-1Ra (anakinra) to tumor immunity. Additionally, we analyze the potential value of IL-1Ra as a biomarker from a clinical perspective. This review is aimed to highlight the important link between inflammation and cancer and provide potential drug targets for future cancer therapy.

NLRP3 and cancer: Pathogenesis and therapeutic opportunities

More than a decade ago IL-1 blockade was suggested as an add-on therapy for the treatment of cancer. This proposal was based on the overall safety record of anti-IL-1 biologics and the anti-tumor properties of IL-1 blockade in animal models of cancer. Today, a new frontier in IL-1 activity regulation has developed with several orally active NLRP3 inhibitors currently in clinical trials, including cancer. Despite an increasing body of evidence suggesting a role of NLRP3 and IL-1-mediated inflammation driving cancer initiation, immunosuppression, growth, and metastasis, NLRP3 activation in cancer remains controversial. In this review, we discuss the recent advances in the understanding of NLRP3 activation in cancer. Further, we discuss the current opportunities for NLRP3 inhibition in cancer intervention with novel small molecules.

Pancreatic Ductal Adenocarcinoma Cells Regulate NLRP3 Activation to Generate a Tolerogenic Microenvironment

Defining feature of pancreatic ductal adenocarcinoma (PDAC) that participates in the high mortality rate and drug resistance is the immune-tolerant microenvironment which enables tumors to progress unabated by adaptive immunity. In this study, we report that PDAC cells release CSF-1 to induce nucleotide-binding domain, leucine-rich containing family, pyrin domain-containing-3 (NLRP3) activation in myeloid cells. Increased NLRP3 expression was found in the pancreas of patients with PDAC when compared with normal pancreas which correlated with the formation of the NLRP3 inflammasome. Using human primary cells and an orthotopic PDAC mouse model, we show that NLRP3 activation is responsible for the maturation and release of the inflammatory cytokine IL1β which selectively drives Th2-type inflammation via COX2/PGE2 induction. As a result of this inflammation, primary tumors were characterized by reduced cytotoxic CD8+ T-cell activation and increased tumor expansion. Genetic deletion and pharmacologic inhibition of NLRP3 enabled the development of Th1 immunity, increased intratumoral levels of IL2, CD8+ T cell–mediated tumor suppression, and ultimately limited tumor growth. In addition, we observed that NLRP3 inhibition in combination with gemcitabine significantly increased the efficacy of the chemotherapy. In conclusion, this study provides a mechanism by which tumor-mediated NLRP3 activation exploits a distinct adaptive immunity response that facilitates tumor escape and progression. Considering the ability to block NLRP3 activity with safe and small orally active molecules, this protein represents a new promising target to improve the limited therapeutic options in PDAC.

SIGNIFICANT

This study provides novel molecular insights on how PDAC cells exploit NLRP3 activation to suppress CD8 T-cell activation. From a translational perspective, we demonstrate that the combination of gemcitabine with the orally active NLRP3 inhibitor OLT1177 increases the efficacy of monotherapy.

A protein-based machine learning approach to the identification of inflammatory subtypes in pancreatic ductal adenocarcinoma

BACKGROUND/OBJECTIVES

The inherently immunosuppressive tumor microenvironment along with the heterogeneity of pancreatic ductal adenocarcinoma (PDAC) limits the effectiveness of available treatment options and contributes to the disease lethality. Using a machine learning algorithm, we hypothesized that PDAC may be categorized based on its microenvironment inflammatory milieu.

METHODS

Fifty-nine tumor samples from patients naïve to treatment were homogenized and probed for 41 unique inflammatory proteins using a multiplex assay. Subtype clustering was determined using t-distributed stochastic neighbor embedding (t-SNE) machine learning analysis of cytokine/chemokine levels. Statistics were performed using Wilcoxon rank sum test and Kaplan-Meier survival analysis.

RESULTS

t-SNE analysis of tumor cytokines/chemokines revealed two distinct clusters, immunomodulating and immunostimulating. In pancreatic head tumors, patients in the immunostimulating group (N = 26) were more likely to be diabetic (p = 0.027), but experienced less intraoperative blood loss (p = 0.0008). Though there were no significant differences in survival (p = 0.161), the immunostimulating group trended toward longer median survival by 9.205 months (11.28 vs. 20.48 months).

CONCLUSION

A machine learning algorithm identified two distinct subtypes within the PDAC inflammatory milieu, which may influence diabetes status as well as intraoperative blood loss. Opportunity exists to further explore how these inflammatory subtypes may influence treatment response, potentially elucidating targetable mechanisms of PDAC's immunosuppressive tumor microenvironment.

Splicing Factor SRSF1 Promotes Pancreatitis and KRASG12D-Mediated Pancreatic Cancer

Inflammation is strongly associated with pancreatic ductal adenocarcinoma (PDAC), a highly lethal malignancy. Dysregulated RNA splicing factors have been widely reported in tumorigenesis, but their involvement in pancreatitis and PDAC is not well understood. Here, we report that the splicing factor SRSF1 is highly expressed in pancreatitis, PDAC precursor lesions, and tumors. Increased SRSF1 is sufficient to induce pancreatitis and accelerate KRASG12D-mediated PDAC. Mechanistically, SRSF1 activates MAPK signaling-partly by upregulating interleukin 1 receptor type 1 (IL1R1) through alternative-splicing-regulated mRNA stability. Additionally, SRSF1 protein is destabilized through a negative feedback mechanism in phenotypically normal epithelial cells expressing KRASG12D in mouse pancreas and in pancreas organoids acutely expressing KRASG12D, buffering MAPK signaling and maintaining pancreas cell homeostasis. This negative feedback regulation of SRSF1 is overcome by hyperactive MYC, facilitating PDAC tumorigenesis. Our findings implicate SRSF1 in the etiology of pancreatitis and PDAC, and point to SRSF1-misregulated alternative splicing as a potential therapeutic target.

SIGNIFICANCE

We describe the regulation of splicing factor SRSF1 expression in the context of pancreas cell identity, plasticity, and inflammation. SRSF1 protein downregulation is involved in a negative feedback cellular response to KRASG12D expression, contributing to pancreas cell homeostasis. Conversely, upregulated SRSF1 promotes pancreatitis and accelerates KRASG12D-mediated tumorigenesis through enhanced IL1 and MAPK signaling. This article is highlighted in the In This Issue feature, p. 1501.

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.

Cancer-associated fibroblasts: from basic science to anticancer therapy

Cancer-associated fibroblasts (CAFs), as a central component of the tumor microenvironment in primary and metastatic tumors, profoundly influence the behavior of cancer cells and are involved in cancer progression through extensive interactions with cancer cells and other stromal cells. Furthermore, the innate versatility and plasticity of CAFs allow their education by cancer cells, resulting in dynamic alterations in stromal fibroblast populations in a context-dependent manner, which highlights the importance of precise assessment of CAF phenotypical and functional heterogeneity. In this review, we summarize the proposed origins and heterogeneity of CAFs as well as the molecular mechanisms regulating the diversity of CAF subpopulations. We also discuss current strategies to selectively target tumor-promoting CAFs, providing insights and perspectives for future research and clinical studies involving stromal targeting.

Regulation of PD-L1 expression in non-small cell lung cancer by interleukin-1β

Introduction

Programmed cell death-ligand 1 (PD-L1) is a biomarker for prediction of the clinical efficacy of immune checkpoint inhibitors in various cancer types. The role of cytokines in regulation of PD-L1 expression in tumor cells has not been fully characterized, however. Here we show that interleukin-1β (IL-1β) plays a key role in regulation of PD-L1 expression in non-small cell lung cancer (NSCLC).

Methods

We performed comprehensive screening of cytokine gene expression in NSCLC tissue using available single-cell RNA-Sequence data. Then we examined the role of IL-1β in vitro to elucidate its induction of PD-L1 on NSCLC cells.

Results

The IL-1β gene is highly expressed in the tumor microenvironment, particularly in macrophages. The combination of IL-1β and interferon-γ (IFN-γ) induced a synergistic increase in PD-L1 expression in NSCLC cell lines. IL-1β and IFN-γ also cooperatively activated mitogen-activated protein kinase (MAPK) signaling and promoted the binding of downstream transcription factors to the PD-L1 gene promoter. Furthermore, inhibitors of MAPK signaling blocked upregulation of PD-L1 by IL-1β and IFN-γ.

Discussion

Our study reports high levels of IL-1β in the tumor microenvironment may cooperate with IFN-γ to induce maximal PD-L1 expression in tumor cells via activation of MAPK signaling, with the IL-1β-MAPK axis being a promising therapeutic target for attenuation of PD-L1-mediated suppression of antitumor immunity.

The platelet pannexin 1-IL-1β axis orchestrates pancreatic ductal adenocarcinoma invasion and metastasis

We aimed to investigate the protumor mechanisms of platelets in pancreatic ductal adenocarcinoma (PDAC). Serum samples were collected from 656 PDAC patients and 3105 healthy people, and a Panx1 knockout tumor model and an adoptive platelet transfusion mouse model were established. We showed that the blood platelet counts were not significantly different between stage III/IV and stage I/II patients, while the number of the CD41+/CD62P+ platelets was significantly elevated in stage III/IV patients, indicating that CD41+/CD62P+ platelets are associated with a poor prognosis. Further analysis showed that a high level of CD41+/CD62P+ platelets was significantly correlated with microvascular invasion (P = 0.002), advanced 8th edition AJCC stage (P < 0.001), and a high CA19-9 level (P = 0.027) and independently predicted a poor prognosis for resectable I/II PDAC. Furthermore, we found significantly higher Panx1 expression in CD41+/CD62P+ platelets than in CD41+/CD62P- platelets in PDAC patients. Mechanistically, Panx1 was able to enhance IL-1β secretion in CD41+/CD62P+ platelets by phosphorylating p38 MAPK and consequently promoted the invasion and metastasis of PDAC cells. Finally, we synthesized a novel compound named PC63435 by the ligation of carbenoxolone (a Panx1 inhibitor) and PSGL-1 (a CD62P ligand). PC63435 specifically bound to CD41+/CD62P+ platelets, then blocked the Panx1/IL-1β pathway and reduced the proportion of CD41+/CD62P+ platelets, which suppressed PDAC tumor invasion and metastasis in vivo. These results demonstrated that the Panx1/IL-1β axis in CD41+/CD62P+ platelets enhanced PDAC cell malignancy and that this axis may be a promising target for PDAC therapy.

Blockade of IL-1α and IL-1β signaling by the anti-IL1RAP antibody nadunolimab (CAN04) mediates synergistic anti-tumor efficacy with chemotherapy

IL-1α and IL-1β are both involved in several aspects of tumor biology, including tumor initiation, progression, metastasis, and not least in resistance to various therapies. IL-1α can function as an alarmin to signal cellular stress, and acts to induce downstream events, including production of IL-1β, to amplify the signal. Both IL-1α and IL-1β act through the same receptor complex, IL-1R1-IL1RAP, to mediate signal transduction. IL1RAP is expressed on tumor cells and in the tumor microenvironment by for example CAF, macrophages and endothelial cells. The anti-IL1RAP antibody nadunolimab (CAN04) inhibits both IL-1α and IL-1β signaling and induces ADCC of IL1RAP-expressing tumor cells. As both IL-1α and IL-1β mediate chemoresistance, the aim of this study was to explore the potential synergy between nadunolimab and chemotherapy. This was performed using the NSCLC PDX model LU2503 and the syngeneic MC38 model, in addition to in vitro cell line experiments. We show that chemotherapy induces expression and release of IL-1α from tumor cells and production of IL-1β-converting enzyme, ICE, in the tumor stroma. IL-1α is also demonstrated to act on stromal cells to further induce the secretion of IL-1β, an effect disrupted by nadunolimab. Nadunolimab, and its surrogate antibody, synergize with platinum-based as well as non-platinum-based chemotherapy to induce potent anti-tumor effects, while blockade of only IL-1β signaling by anti-IL-1β antibody does not achieve this effect. In conclusion, blockade of IL1RAP with nadunolimab reduces IL-1-induced chemoresistance of tumors.

Endotoxemia and Gastrointestinal Cancers: Insight into the Mechanisms Underlying a Dangerous Relationship

Lipopolysaccharide (LPS), also known as endotoxin, is a component of the membrane of gram-negative bacteria and a well-recognized marker of sepsis. In case of disruption of the intestinal barrier, as occurs with unhealthy diets, alcohol consumption, or during chronic diseases, the microbiota residing in the gastrointestinal tract becomes a crucial factor in amplifying the systemic inflammatory response. Indeed, the translocation of LPS into the bloodstream and its interaction with toll-like receptors (TLRs) triggers molecular pathways involved in cytokine release and immune dysregulation. This is a critical step in the exacerbation of many diseases, including metabolic disorders and cancer. Indeed, the role of LPS in cancer development is widely recognized, and examples include gastric tumor related to Helicobacter pylori infection and hepatocellular carcinoma, both of which are preceded by a prolonged inflammatory injury; in addition, the risk of recurrence and development of metastasis appears to be associated with endotoxemia. Here, we review the mechanisms that link the promotion and progression of tumorigenesis with endotoxemia, and the possible therapeutic interventions that can be deployed to counteract these events.

Steroid receptor coactivator-3 inhibition generates breast cancer antitumor immune microenvironment

BACKGROUND

The tumor immune microenvironment (TIME) generated by cancer-infiltrating immune cells has a crucial role in promoting or suppressing breast cancer progression. However, whether the steroid receptor coactivator-3 (SRC-3) modulates TIME to progress breast cancer is unclear. Therefore, the present study evaluates whether SRC-3 generates a tumor-promoting TIME in breast tumors using a syngeneic immune-intact mouse model of breast cancer.

METHODS

We employed E0771 and 4T1 breast cancer in immune-intact syngeneic female C57BL/6 and BALB/c mice, respectively. SI-2, a specific small-molecule inhibitor of SRC-3, was administered daily (2.5 mg/kg) to E0771 and 4T1 breast tumor-bearing immune-intact mice. In addition, SRC-3 knockdown (KD)-E0771 and SRC-3 KD-4T1 cells and their parental breast cancer cells were injected into their syngeneic immune-intact female mice versus immune-deficiency mice to validate that the host immune system is required for breast tumor suppression by SRC-3 KD in immune-intact mice. Furthermore, tumor-infiltrating immune cells (such as CD4+, CD8+, CD56+, and Foxp3+ cells) in E0771 and 4T1 breast cancers treated with SI-2 and in SRC-3 KD E0771 and 4T1 breast cancers were determined by immunohistochemistry. Additionally, cytokine levels in SI-2-treated and SRC-3 KD E0771 breast tumors and their control cancers were defined with a Mouse Cytokine Array.

RESULTS

SRC-3 inhibition by SI-2 significantly suppressed the progression of breast cancer cells (E0771 and 4T1) into breast cancers in immune-intact syngeneic female mice. SRC-3 KD-E0771 and -4T1 breast cancer cells did not produce well-developed tumors in immune-intact syngeneic female mice compared to their parental cells, but SRC-3 KD breast cancers were well developed in immune-defective host mice. SRC-3 inhibition by SI-2 and SRC-3 KD effectively increased the numbers of cytotoxic immune cells, such as CD4+ and CD8+ T cells and CD56+ NK cells, and Interferon γ (Ifng) in breast cancers compared to vehicle. However, SI-2 treatment reduced the number of tumor-infiltrating CD4+/Foxp3+ regulatory T (Treg) cells compared to vehicle treatment. In addition, SRC-3 inhibition by SI-2 and SRC-3 KD increased C-X-C motif chemokine ligand 9 (Cxcl9) expression in breast cancer to recruit C-X-C motif chemokine receptor 3 (Cxcr3)-expressing cytotoxic immune cells into breast tumors.

CONCLUSIONS

SRC-3 is a critical immunomodulator in breast cancer, generating a protumor immune microenvironment. SRC-3 inhibition by SI-2 or SRC-3 KD activates the Cxcl9/Cxcr3 axis in breast tumors and enhances the antitumor immune microenvironment to suppress breast cancer progression.

Exploring the Biology of Cancer-Associated Fibroblasts in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy characterised by a stubbornly low 5-year survival which is essentially unchanged in the past 5 decades. Despite recent advances in chemotherapy and surgical outcomes, progress continues to lag behind that of other cancers. The PDAC microenvironment is characterised by a dense, fibrotic stroma of which cancer-associated fibroblasts (CAFs) are key players. CAFs and fibrosis were initially thought to be uniformly tumour-promoting, however this doctrine is now being challenged by a wealth of evidence demonstrating CAF phenotypic and functional heterogeneity. Recent technological advances have allowed for the molecular profiling of the PDAC tumour microenvironment at exceptional detail, and these technologies are being leveraged at pace to improve our understanding of this previously elusive cell population. In this review we discuss CAF heterogeneity and recent developments in CAF biology. We explore the complex relationship between CAFs and other cell types within the PDAC microenvironment. We discuss the potential for therapeutic targeting of CAFs, and we finally provide an overview of future directions for the field and the possibility of improving outcomes for patients with this devastating disease.

HOXA10 promote pancreatic cancer progression via directly activating canonical NF-κB signaling pathway

BACKGROUND

Although transcription factor homeobox A10 (HOXA10) plays an important role in regulating the development of the pancreas, a pathway of HOXA10 participates in pancreatic ductal adenocarcinoma (PDAC) progression has not been revealed.

METHODS

Immunohistochemistry assays were applied to demonstrate the relationship between HOXA10 expression and PDAC progression. Functional assays were used to illustrate the oncogenic role of HOXA10 in PDAC progression. Regulatory mechanisms of HOXA10 induced IKKβ gene transcription and the nuclear transcription factor kappa B (NF-κB) signal pathways activation were also investigated in PDAC cells.

RESULTS

In the current study, we show that HOXA10 expression increased in PDAC with higher tumor stage and poor patient survival in public RNA-seq data suggesting HOXA10 is associated with PDAC progression. HOXA10 promotes PDAC cell proliferation, anchorage colony formation, and xenograft growth by activating canonical NF-κB signaling both in vitro and in vivo. Mechanically, HOXA10 up-regulates IKKβ gene transcription directly and subsequently sustain the activation of NF-κB independent of tumor necrosis factor-alpha in PDAC cells.

CONCLUSION

Collectively, up-regulation of HOXA10 gene expression promote cell growth and tumor progression through directly activating canonical NF-κB signaling in PDAC.

Serum cytokine levels are associated with tumor progression during FOLFIRINOX chemotherapy and overall survival in pancreatic cancer patients

Background

Biomarkers predicting treatment response may be used to stratify patients with pancreatic ductal adenocarcinoma (PDAC) for available therapies. The aim of this study was to evaluate the association of circulating cytokines with FOLFIRINOX response and with overall survival (OS).

Methods

Serum samples were collected before start and after the first cycle of FOLFIRINOX from patients with PDAC (n=83) of all disease stages. Overall, 34 circulating cytokines were analyzed with a multiplex immunoassay. In addition, changes in peripheral blood immune cell counts were determined by flow cytometry to correlate with differences in cytokine levels. Chemotherapy response was determined by CT scans with the RECIST 1.1 criteria, as disease control (n=64) or progressive disease (n=19) within eight cycles of FOLFIRINOX.

Results

Patients with high serum IL-1RA concentrations after one cycle of chemotherapy were less likely to have tumor progression during FOLFIRINOX (OR 0.25, P=0.040). Increase of circulating IL-1RA concentrations correlated with increase of total, classical (CD14+CD16-), and non-classical monocytes (CD14-CD16+), and dendritic cells. In multivariable cox regression, including the variables chemotherapy response outcome and baseline CA19-9 level, serum concentrations of IL-7 (HR 2.14, P=0.010), IL-18 (HR 2.00, P=0.020), and MIP-1β (HR 0.51, P=0.025) after one cycle of FOLFIRINOX showed correlations with OS.

Conclusions

Circulating IL-1RA, IL-7, IL-18, and MIP-1β concentrations are biomarkers associated with FOLFIRINOX response in PDAC patients, suggesting an important role for specific immune cells in chemotherapy response and PDAC progression. Cytokine-based treatment might improve patient outcome and should be evaluated in future studies.

Metabolic Pathways as a Novel Landscape in Pancreatic Ductal Adenocarcinoma

Metabolism plays a fundamental role in both human physiology and pathology, including pancreatic ductal adenocarcinoma (PDAC) and other tumors. Anabolic and catabolic processes do not only have energetic implications but are tightly associated with other cellular activities, such as DNA duplication, redox reactions, and cell homeostasis. PDAC displays a marked metabolic phenotype and the observed reduction in tumor growth induced by calorie restriction with in vivo models supports the crucial role of metabolism in this cancer type. The aggressiveness of PDAC might, therefore, be reduced by interventions on bioenergetic circuits. In this review, we describe the main metabolic mechanisms involved in PDAC growth and the biological features that may favor its onset and progression within an immunometabolic context. We also discuss the need to bridge the gap between basic research and clinical practice in order to offer alternative therapeutic approaches for PDAC patients in the more immediate future.

The application of the Glasgow prognostic score to predict the survival in patients with metastatic pancreatic carcinoma

Objectives:

Thither is a more pressing effort to think about chemotherapy (CTx) in second-line and beyond in patients with metastatic pancreatic cancer (mPC). The current work aimed to evaluate the value of the Glasgow prognostic score (GPS) and modified Glasgow prognostic score (mGPS) to predict the survival in patients receiving second-line CTx protocol.

Material and Methods:

We retrospectively reviewed the patients’ medical files with mPC who received second-line CTx protocol between September 2013 and December 2017. The GPS/mGPS graded from 0 to 2 based on C-reactive protein and serum albumin.

Results:

One hundred and sixty-nine patients with mPC were eligible. Survival of patients with Score 0 (GPS/mGPS) was better than that of Score 1 (GPS/mGPS) or Score 2 (GPS/mGPS), which was statistically significant (P < 0.001). Of 78 patients who died, only 16 patients belonged to Score 0 (GPS/mGPS), compared to 30 patients belonged to Score 1 (GPS/mGPS) and 32 patients belonged to Score 2 (GPS/mGPS). Univariate analysis showed that high GPS/mGPS (P < 0.000) as well as poor Eastern Cooperative Oncology Group Performance Status (P < 0.000) and metastasis either to the liver (P < 0.01) or lung (P < 0.04) were linked with worse prognosis. A statistically significant association was detected between the two scores. Cohen’s Kappa coefficient (k) was 0.9, SD = 0.03; 95% CI (0.787–0.922; P < 0.001).

Conclusion:

Our data suggested that GPS/mGPS is an easy and applicable index that may be used in daily practice and may help in the prognostic stratification of mPC patients to avert overtreatment in frail patients and raise the best supportive treatment concept.

The interactive role of inflammatory mediators and metabolic reprogramming in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is characterized by its highly reactive inflammatory desmoplastic stroma with evidence of an extensive tumor stromal interaction largely mediated by inflammatory factors. KRAS mutation and inflammatory signaling promote protumorigenic events, including metabolic reprogramming with several inter-regulatory crosstalks to fulfill the high demand of energy and regulate oxidative stress for tumor growth and progression. Notably, the more aggressive molecular subtype of PDAC enhances influx of glycolytic intermediates. This review focuses on the interactive role of inflammatory signaling and metabolic reprogramming with emerging evidence of crosstalk, which supports the development, progression, and therapeutic resistance of PDAC. Understanding the emerging crosstalk between inflammation and metabolic adaptations may identify potential targets and develop novel therapeutic approaches for PDAC.

The interleukin-1 axis and the tumor immune microenvironment in pancreatic ductal adenocarcinoma

Interleukin-1 (IL-1) plays a key role in carcinogenesis and several IL-1-targeted therapeutics are under investigation for the treatment of pancreatic ductal adenocarcinoma (PDAC). We sought to broaden our understanding of how the family of IL-1 ligands and receptors impact the tumor immune landscape and patient survival in PDAC. Gene expression data and DNA methylation data for IL1A, IL1B, IL1RN, IL1R1, IL1R2, and IL1RAP was attained from The Cancer Genome Atlas (TCGA) database and cross validated using the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) database. Immune cell-type abundance was estimated using CIBERSORTx. Further confirmatory soluble protein analysis and peripheral blood immunophenotyping were performed on available tissue samples from our institution. 169 PDAC patients and 50 benign pancreatic TCGA-based samples were analyzed. IL1A (p < 0.001), IL1RN (p < 0.001), IL1R2 (p < 0.001), and IL1RAP (p = 0.006) were markedly increased in PDAC tumor tissue compared to benign pancreatic tissue. Furthermore, expression of IL1A, IL1B and IL1R1 were positively correlated with gene expression of immune checkpoints PVR, CD274, CD47, CD80, and HLA-A/B/C (p < 0.001). IL1B and IL1R1 were correlated to expression of PDCD1, CD86, CTLA4 and IDO1 (<0.001). Low expression of IL1RN (p = 0.020), IL1R2 (p = 0.015), and IL1RAP (p = 0.003) and high expression of IL1B (p = 0.031) were correlated with increased patient survival. At the protein level, IL-1β was correlated with increased peripheral central memory CD4+ and CD8+ T-cells as well as decreased Th2 cells. These findings suggest that the IL-1 axis plays a complex and pivotal role in the host immune response to PDAC.

Predictive Biomarkers for a Personalized Approach in Resectable Pancreatic Cancer

The mainstay treatment for patients with immediate resectable pancreatic cancer remains upfront surgery, which represents the only potentially curative strategy. Nevertheless, the majority of patients surgically resected for pancreatic cancer experiences disease relapse, even when a combination adjuvant therapy is offered. Therefore, aiming at improving disease free survival and overall survival of these patients, there is an increasing interest in evaluating the activity and efficacy of neoadjuvant and perioperative treatments. In this view, it is of utmost importance to find biomarkers able to select patients who may benefit from a preoperative therapy rather than upfront surgical resection. Defined genomic alterations and a dynamic inflammatory microenvironment are the major culprits for disease recurrence and resistance to chemotherapeutic treatments in pancreatic cancer patients. Signal transduction pathways or tumor immune microenvironment could predict early recurrence and response to chemotherapy. In the last decade, distinct molecular subtypes of pancreatic cancer have been described, laying the bases to a tailored therapeutic approach, started firstly in the treatment of advanced disease. Patients with homologous repair deficiency, in particular with mutant germline BRCA genes, represent the first subgroup demonstrating to benefit from specific therapies. A fraction of patients with pancreatic cancer could take advantage of genome sequencing with the aim of identifying possible targetable mutations. These genomic driven strategies could be even more relevant in a potentially curative setting. In this review, we outline putative predictive markers that could help in the next future in tailoring the best therapeutic strategy for pancreatic cancer patients with a potentially curable disease.

First-in-human phase 1 dose-escalation study of CAN04, a first-in-class interleukin-1 receptor accessory protein (IL1RAP) antibody in patients with solid tumours

BACKGROUND

Interleukin-1 (IL-1) signalling is involved in various protumoural processes including proliferation, immune evasion, metastasis and chemoresistance. CAN04 is a first-in-class monoclonal antibody that binds IL-1 receptor accessory protein (IL1RAP), required for IL-1 signalling. In this first-in-human phase 1 study, we assessed safety, recommended phase 2 dose (RP2D), pharmacokinetics, pharmacodynamics and preliminary anti-tumour activity of CAN04 monotherapy.

METHODS

Patients with advanced solid tumours known to express IL1RAP and refractory to standard treatments were enrolled in a dose-escalation study with 5 dose levels (1.0-10.0 mg/kg) of weekly CAN04.

RESULTS

Twenty-two patients were enrolled. Most common adverse events were infusion-related reactions (41%), fatigue (32%), constipation (27%), diarrhoea (27%), decreased appetite (23%), nausea (23%) and vomiting (23%). One dose limiting toxicity was reported. No maximum tolerated dose was identified. Pharmacokinetics analyses indicate higher exposures and slower elimination with increasing doses. Decreases in serum IL-6 and CRP were observed in most patients. Twenty-one patients were evaluable for response, 43% had stable disease per immune-related response criteria with no partial/complete responses.

CONCLUSIONS

The IL1RAP targeting antibody CAN04 can be safely administered to patients up to 10.0 mg/kg weekly, which was defined as the RP2D. Serum biomarkers supported target engagement and IL-1 pathway inhibition.

CLINICAL TRIAL REGISTRATION

NCT03267316.

Interleukin-1 signaling in solid organ malignancies

As inflammation plays a critical role in the development and progression of cancer, therapeutic targeting of cytokine pathways involved in both tumorigenesis and dictating response to clinical treatments are of significant interest. Recent evidence has highlighted the importance of the pro-inflammatory cytokine interleukin-1 (IL-1) as a key mediator of tumor growth, metastatic disease spread, immunosuppression, and drug resistance in cancer. IL-1 promotes tumorigenesis through diverse mechanisms, including the activation of oncogenic signaling pathways directly in tumor cells and via orchestrating crosstalk between the cellular constituents of the tumor microenvironment (TME), thereby driving cancer growth. This review will provide an overview of IL-1 signaling and physiology and summarize the disparate mechanisms involving IL-1 in tumorigenesis and cancer progression. Additionally, clinical studies targeting IL-1 signaling in the management of solid organ tumors will be summarized herein.

IL-1β-Induced Elevation of Solute Carrier Family 7 Member 11 Promotes Hepatocellular Carcinoma Metastasis Through Up-regulating Programmed Death Ligand 1 and Colony-Stimulating Factor 1

BACKGROUND AND AIMS

Because of a paucity of effective treatment options, metastasis is still a major cause for HCC-associated mortality. The molecular mechanism of inflammation-induced HCC metastasis is open for study. Here, we characterized the function of solute carrier family 7 member 11 (SLC7A11) in inflammation-related HCC metastasis and probed therapy strategies for this subpopulation of patients.

APPROACH AND RESULTS

Elevated expression of SLC7A11 was positively correlated with poor tumor differentiation, and higher tumor-nodule-metastasis stage, and indicated poor prognosis in human HCC. SLC7A11 increased HIF1α expression through reducing α-ketoglutarate (αKG) level by exporting glutamate. SLC7A11 up-regulated programmed death ligand 1 (PD-L1) and colony-stimulating factor 1 (CSF1) expression through αKG-HIF1α cascade. SLC7A11 overexpression in HCC cells promoted intratumoral tumor-associated macrophage (TAM) and myeloid-derived suppressor cell (MDSC) infiltration through the CSF1/colony-stimulating factor 1 receptor (CSF1R) axis, whereas knockdown of CSF1 attenuated SLC7A11-mediated intratumoral TAM and MDSC infiltration and HCC metastasis. Depletion of either TAMs or MDSCs decreased SLC7A11-mediated HCC metastasis. Furthermore, the combination of CSF1R inhibitor BZL945 and anti-PD-L1 antibody blocked SLC7A11-induced HCC metastasis. In addition, IL-1β up-regulated SLC7A11 expression through the interleukin-1 receptor type 1 (IL-1R1)/extracellular signal-regulated kinase/specificity protein 1 pathway. SLC7A11 knockdown impaired IL-1β-promoted HCC metastasis. Anakinra, an IL-1R1 antagonist, reversed IL-1β-promoted HCC metastasis. In human HCC tissues, SLC7A11 expression was positively associated with HIF1α, PD-L1, and CSF1 expression and intratumoral TAM and MDSC infiltration.

CONCLUSIONS

IL-1β-induced SLC7A11 overexpression up-regulated PD-L1 and CSF1 through the αKG/HIF1α axis, which promoted TAM and MDSC infiltration. Interruption of this oncogenic loop may provide a promising therapy strategy for the inhibition of SLC7A11-mediated HCC metastasis.

Oncogenic KRAS-Induced Feedback Inflammatory Signaling in Pancreatic Cancer: An Overview and New Therapeutic Opportunities

Pancreatic ductal adenocarcinoma (PDAC) remains highly refractory to treatment. While the KRAS oncogene is present in almost all PDAC cases and accounts for many of the malignant feats of PDAC, targeting KRAS or its canonical, direct effector cascades remains unsuccessful in patients. The recalcitrant nature of PDAC is also heavily influenced by its highly fibro-inflammatory tumor microenvironment (TME), which comprises an acellular extracellular matrix and various types of non-neoplastic cells including fibroblasts, immune cells, and adipocytes, underscoring the critical need to delineate the bidirectional signaling interplay between PDAC cells and the TME in order to develop novel therapeutic strategies. The impact of tumor-cell KRAS signaling on various cell types in the TME has been well covered by several reviews. In this article, we critically reviewed evidence, including work from our group, on how the feedback inflammatory signals from the TME impact and synergize with oncogenic KRAS signaling in PDAC cells, ultimately augmenting their malignant behavior. We discussed past and ongoing clinical trials that target key inflammatory pathways in PDAC and highlight lessons to be learned from outcomes. Lastly, we provided our perspective on the future of developing therapeutic strategies for PDAC through understanding the breadth and complexity of KRAS and the inflammatory signaling network.

The cytokine storms of COVID-19, H1N1 influenza, CRS and MAS compared. Can one sized treatment fit all?

An analysis of published data appertaining to the cytokine storms of COVID-19, H1N1 influenza, cytokine release syndrome (CRS), and macrophage activation syndrome (MAS) reveals many common immunological and biochemical abnormalities. These include evidence of a hyperactive coagulation system with elevated D-dimer and ferritin levels, disseminated intravascular coagulopathy (DIC) and microthrombi coupled with an activated and highly permeable vascular endothelium. Common immune abnormalities include progressive hypercytokinemia with elevated levels of TNF-α, interleukin (IL)-6, and IL-1β, proinflammatory chemokines, activated macrophages and increased levels of nuclear factor kappa beta (NFκB). Inflammasome activation and release of damage associated molecular patterns (DAMPs) is common to COVID-19, H1N1, and MAS but does not appear to be a feature of CRS. Elevated levels of IL-18 are detected in patients with COVID-19 and MAS but have not been reported in patients with H1N1 influenza and CRS. Elevated interferon-γ is common to H1N1, MAS, and CRS but levels of this molecule appear to be depressed in patients with COVID-19. CD4+ T, CD8+ and NK lymphocytes are involved in the pathophysiology of CRS, MAS, and possibly H1N1 but are reduced in number and dysfunctional in COVID-19. Additional elements underpinning the pathophysiology of cytokine storms include Inflammasome activity and DAMPs. Treatment with anakinra may theoretically offer an avenue to positively manipulate the range of biochemical and immune abnormalities reported in COVID-19 and thought to underpin the pathophysiology of cytokine storms beyond those manipulated via the use of, canakinumab, Jak inhibitors or tocilizumab. Thus, despite the relative success of tocilizumab in reducing mortality in COVID-19 patients already on dexamethasone and promising results with Baricitinib, the combination of anakinra in combination with dexamethasone offers the theoretical prospect of further improvements in patient survival. However, there is currently an absence of trial of evidence in favour or contravening this proposition. Accordingly, a large well powered blinded prospective randomised controlled trial (RCT) to test this hypothesis is recommended.

Noise-Induced Cochlear Damage Involves PPAR Down-Regulation through the Interplay between Oxidative Stress and Inflammation

The cross-talk between oxidative stress and inflammation seems to play a key role in noise-induced hearing loss. Several studies have addressed the role of PPAR receptors in mediating antioxidant and anti-inflammatory effects and, although its protective activity has been demonstrated in several tissues, less is known about how PPARs could be involved in cochlear dysfunction induced by noise exposure. In this study, we used an in vivo model of noise-induced hearing loss to investigate how oxidative stress and inflammation participate in cochlear dysfunction through PPAR signaling pathways. Specifically, we found a progressive decrease in PPAR expression in the cochlea after acoustic trauma, paralleled by an increase in oxidative stress and inflammation. By comparing an antioxidant (Q-ter) and an anti-inflammatory (Anakinra) treatment, we demonstrated that oxidative stress is the primary element of damage in noise-induced cochlear injury and that increased inflammation can be considered a consequence of PPAR down-regulation induced by ROS production. Indeed, by decreasing oxidative stress, PPARs returned to control values, reactivating the negative control on inflammation in a feedback loop.

Baseline Plasma Inflammatory Profile Is Associated With Response to Neoadjuvant Chemotherapy in Patients With Pancreatic Adenocarcinoma

Despite its increased application in pancreatic ductal adenocarcinoma (PDAC), complete response to neoadjuvant therapy (NAT) is rare. Given the critical role of host immunity in regulating cancer, we sought to correlate baseline inflammatory profiles to significant response to NAT. PDAC patients receiving NAT were classified as responders (R) or nonresponders (NR) by carbohydrate antigen 19-9 response, pathologic tumor size, and lymph node status in the resected specimen. Baseline (treatment-naive) plasma was analyzed to determine levels of 27 inflammatory mediators. Logistic regression was used to correlate individual mediators with response. Network analysis and Pearson correlation maps were derived to determine baseline inflammatory mediator profiles. Forty patients (20R and 20NR) met study criteria. The R showed significantly higher overall survival (59.4 vs. 21.25 mo, P=0.002) and disease-free survival (50.97 vs. 10.60 mo, P=0.005), compared with NR. soluble interleukin-2 receptor alpha was a significant predictor of no response to NAT (P=0.045). Analysis of inflammatory profiles using the Pearson heat map analysis followed by network analysis depicted increased inflammatory network complexity in NR compared with R (1.69 vs. 1), signifying a more robust baseline inflammatory status of NR. A panel of inflammatory mediators identified by logistic regression and Fischer score analysis was used to create a potential decision tree to predict NAT response. We demonstrate that baseline inflammatory profiles are associated with response to NAT in PDAC, and that an upregulated inflammatory status is associated with a poor response to NAT. Further analysis into the role of inflammatory mediators as predictors of chemotherapy response is warranted.

Protective effect of combination of anakinra and MCC950 against acute lung injury is achieved through suppression of the NF-κB-mediated-MAPK and NLRP3-caspase pathways

BACKGROUND

It has been uncovered that the interleukin-1 receptor antagonist anakinra and the NLRP3 inflammasome blocker MCC950 can alleviate acute lung injury (ALI). However, the specific mechanism underlying these effects remains unknown. Thus, we sought to investigate the effects of anakinra and MCC950 in ALI as well as the molecular mechanisms.

METHODS

We treated C57BL/6 mice with aerosols of anakinra and/or MCC950 along with lipopolysaccharide (LPS), followed by mechanical ventilation (MV) treatment after 1.5 h of inhalation of aforementioned compounds. Lung injury was assessed by determining the level of inflammatory factors in the alveolar lavage fluid and monitoring blood oxygen saturation. We confirmed our findings of regulation of the ALI model through the nuclear factor-κB (NF-κB)/mitogen-activated protein kinase (MAPK)/nucleotide binding domain and leucine-rich repeat (NLR) pyrin domain containing 3 (NLRP3)-caspase pathway in further studies with RelA^-/- mice.

RESULTS

Combined treatment of anakinra and MCC950 presented the best therapeutic effect on LPS and MV-induced ALI than did treatment with anakinra or MCC950 alone. Combined therapy with anakinra and MCC950 suppressed MAPK and NLRP3-caspase via inhibition of the NF-κB pathway to improve ALI, but the therapeutic pathway was revoked by knockout of NF-κB.

CONCLUSION

Taken together, combined treatment of anakinra and MCC950 was effective in alleviating ALI in the mouse model, highlighting a new insight into ALI treatment.

Dynamic roles of inflammasomes in inflammatory tumor microenvironment

The inflammatory tumor microenvironment has been known to be closely connected to all stages of cancer development, including initiation, promotion, and progression. Systemic inflammation in the tumor microenvironment is increasingly being recognized as an important prognostic marker in cancer patients. Inflammasomes are master regulators in the first line of host defense for the initiation of innate immune responses. Inflammasomes sense pathogen-associated molecular patterns and damage-associated molecular patterns, following recruitment of immune cells into infection sites. Therefore, dysregulated expression/activation of inflammasomes is implicated in pathogenesis of diverse inflammatory disorders. Recent studies have demonstrated that inflammasomes play a vital role in regulating the development and progression of cancer. This review focuses on fate-determining roles of the inflammasomes and the principal downstream effector cytokine, IL-1β, in the tumor microenvironment.

TPL2 enforces RAS-induced inflammatory signaling and is activated by point mutations

NF-κB transcription factors, driven by the IRAK/IKK cascade, confer treatment resistance in pancreatic ductal adenocarcinoma (PDAC), a cancer characterized by near-universal KRAS mutation. Through reverse-phase protein array and RNA sequencing we discovered that IRAK4 also contributes substantially to MAPK activation in KRAS-mutant PDAC. IRAK4 ablation completely blocked RAS-induced transformation of human and murine cells. Mechanistically, expression of mutant KRAS stimulated an inflammatory, autocrine IL-1β signaling loop that activated IRAK4 and the MAPK pathway. Downstream of IRAK4, we uncovered TPL2 (also known as MAP3K8 or COT) as the essential kinase that propels both MAPK and NF-κB cascades. Inhibition of TPL2 blocked both MAPK and NF-κB signaling, and suppressed KRAS-mutant cell growth. To counter chemotherapy-induced genotoxic stress, PDAC cells upregulated TLR9, which activated prosurvival IRAK4/TPL2 signaling. Accordingly, a TPL2 inhibitor synergized with chemotherapy to curb PDAC growth in vivo. Finally, from TCGA we characterized 2 MAP3K8 point mutations that hyperactivate MAPK and NF-κB cascades by impeding TPL2 protein degradation. Cancer cell lines naturally harboring these MAP3K8 mutations are strikingly sensitive to TPL2 inhibition, underscoring the need to identify these potentially targetable mutations in patients. Overall, our study establishes TPL2 as a promising therapeutic target in RAS- and MAP3K8-mutant cancers and strongly prompts development of TPL2 inhibitors for preclinical and clinical studies.

Interleukin-1β-induced pancreatitis promotes pancreatic ductal adenocarcinoma via B lymphocyte-mediated immune suppression

OBJECTIVE

Long-standing chronic pancreatitis is an established risk factor for pancreatic ductal adenocarcinoma (PDAC). Interleukin-1β (IL-1β) has been associated in PDAC with shorter survival. We employed murine models to investigate the mechanisms by which IL-1β and chronic pancreatitis might contribute to PDAC progression.

DESIGN

We crossed LSL-Kras^+/G12D;Pdx1-Cre (KC) mice with transgenic mice overexpressing IL-1β to generate KC-IL1β mice, and followed them longitudinally. We used pancreatic 3D in vitro culture to assess acinar-to-ductal metaplasia formation. Immune cells were analysed by flow cytometry and immunohistochemical staining. B lymphocytes were adoptively transferred or depleted in Kras-mutant mice. B-cell infiltration was analysed in human PDAC samples.

RESULTS

KC-IL1β mice developed PDAC with liver metastases. IL-1β treatment increased Kras^+/G12D pancreatic spheroid formation. CXCL13 expression and B lymphocyte infiltration were increased in KC-IL1β pancreata. Adoptive transfer of B lymphocytes from KC-IL1β mice promoted tumour formation, while depletion of B cells prevented tumour progression in KC-IL1β mice. B cells isolated from KC-IL1β mice had much higher expression of PD-L1, more regulatory B cells, impaired CD8⁺ T cell activity and promoted tumorigenesis. IL-35 was increased in the KC-IL1β pancreata, and depletion of IL-35 decreased the number of PD-L1⁺ B cells. Finally, in human PDAC samples, patients with PDAC with higher B-cell infiltration within tumours showed significantly shorter survival.

CONCLUSION

We show here that IL-1β promotes tumorigenesis in part by inducing an expansion of immune-suppressive B cells. These findings point to the growing significance of B suppressor cells in pancreatic tumorigenesis.

Diversity and Biology of Cancer-Associated Fibroblasts

Efforts to develop anti-cancer therapies have largely focused on targeting the epithelial compartment, despite the presence of non-neoplastic stromal components that substantially contribute to the progression of the tumor. Indeed, cancer cell survival, growth, migration, and even dormancy are influenced by the surrounding tumor microenvironment (TME). Within the TME, cancer-associated fibroblasts (CAFs) have been shown to play several roles in the development of a tumor. They secrete growth factors, inflammatory ligands, and extracellular matrix proteins that promote cancer cell proliferation, therapy resistance, and immune exclusion. However, recent work indicates that CAFs may also restrain tumor progression in some circumstances. In this review, we summarize the body of work on CAFs, with a particular focus on the most recent discoveries about fibroblast heterogeneity, plasticity, and functions. We also highlight the commonalities of fibroblasts present across different cancer types, and in normal and inflammatory states. Finally, we present the latest advances regarding therapeutic strategies targeting CAFs that are undergoing preclinical and clinical evaluation.

HOX Genes Family and Cancer: A Novel Role for Homeobox B9 in the Resistance to Anti-Angiogenic Therapies

Simple Summary

The inhibition of angiogenesis, relying on the use of drugs targeting the VEGF signaling pathway, has become one of the main strategies for cancer treatment. However, the intrinsic and acquired resistance to this type of therapy limit its efficacy. Thus, the identification of novel therapeutic targets is urgently needed. The resistance to anti-angiogenic treatment often occurs through the activation of alternative VEGF independent signaling pathways and recruitment of bone marrow-derived pro-angiogenic cells in the tumor microenvironment. HOX genes are key regulators of embryonic development, also involved in angiogenesis and in cancer progression. HOXB9 upregulation occurs in many types of cancer and it has been identified as a critical transcription factor involved in tumour resistance to anti-angiogenic drugs. Indeed, HOXB9 modulates the expression of alternative pro-angiogenic secreted factors in the tumour microenvironment leading tumor escape from the anti-angiogenic treatments. Hence, HOXB9 could serves as a novel therapeutic target to overcome the resistance to anti-angiogenic therapies.

Abstract

Angiogenesis is one of the hallmarks of cancer, and the inhibition of pro-angiogenic factors and or their receptors has become a primary strategy for cancer therapy. However, despite promising results in preclinical studies, the majority of patients either do not respond to these treatments or, after an initial period of response, they develop resistance to anti-angiogenic agents. Thus, the identification of a novel therapeutic target is urgently needed. Multiple mechanisms of resistance to anti-angiogenic therapy have been identified, including the upregulation of alternative angiogenic pathways and the recruitment of pro-angiogenic myeloid cells in the tumor microenvironment. Homeobox containing (HOX) genes are master regulators of embryonic development playing a pivotal role during both embryonic vasculogenesis and pathological angiogenesis in adults. The importance of HOX genes during cancer progression has been reported in many studies. In this review we will give a brief description of the HOX genes and their involvement in angiogenesis and cancer, with particular emphasis on HOXB9 as a possible novel target for anti-angiogenic therapy. HOXB9 upregulation has been reported in many types of cancers and it has been identified as a critical transcription factor involved in resistance to anti-angiogenic drugs.

Regulation of PD-L1 expression in K-ras-driven cancers through ROS-mediated FGFR1 signaling

K-ras mutations are major genetic events that drive cancer development associated with aggressive malignant phenotypes, while expression of the immune checkpoint molecule PD-L1 plays a key role in cancer evasion of the immune surveillance that also profoundly affects the patient outcome. However, the relationship between K-ras oncogenic signal and PD-L1 expressions as an important area that requires further investigation. Using both in vitro and in vivo experimental models of K-ras-driven cancer, we found that oncogenic K-ras significantly enhanced PD-L1 expression through a redox-mediated mechanism. Activation of K-ras^G12V promoted ROS generation and induced FGFR1 expression, leading to a significant upregulation of PD-L1. We further showed that exogenous ROS such as hydrogen peroxide alone was sufficient to activate FGFR1 and induce PD-L1, while antioxidants could largely abrogate PD-L1 expression in K-ras mutant cells, indicating a critical role of redox regulation. Importantly, genetic knockout of FGFR1 led to a decrease in PD-L1 expression, and impaired tumor growth in vivo due to a significant increase of T cell infiltration in the tumor tissues and thus enhanced T-cell-mediated tumor suppression.

Our study has identified a novel mechanism by which K-ras promotes PD-L1 expression, and suggests that modulation of ROS or inhibition of the FGFR1 pathway could be a novel strategy to abrogate PD-L1-mediated immunosuppression and thus potentially improve the efficacy of immunotherapy in K-ras-driven cancers.

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Oncogenic K-Ras up-regulates PD-L1 expression in vitro and in vivo.

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ROS play a major role in mediating K-Ras-induced FGFR1 activation leading to PD-L1 expression in K-Ras-driven cancers.

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Antioxidants are able to modulate PD-L1 expression in K-Ras mutant cancer cells.

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Suppression of FGFR1 enhances CD8⁺ T cell infiltration and inhibits tumor growth.

Beyond just a tight fortress: contribution of stroma to epithelial-mesenchymal transition in pancreatic cancer

Novel effective treatment is direly needed for patients with pancreatic ductal adenocarcinoma (PDAC). Therapeutics that target the driver mutations, especially the KRAS oncoprotein and its effector cascades, have been ineffective. It is increasing clear that the extensive fibro-inflammatory stroma (or desmoplasia) of PDAC plays an active role in the progression and therapeutic resistance of PDAC. The desmoplastic stroma is composed of dense extracellular matrix (ECM) deposited mainly by the cancer-associated-fibroblasts (CAFs) and infiltrated with various types of immune cells. The dense ECM functions as a physical barrier that limits tumor vasculatures and distribution of therapeutics to PDAC cells. In addition, mounting evidence have demonstrated that both CAFs and ECM promote PDAC cells aggressiveness through multiple mechanisms, particularly engagement of the epithelial-mesenchymal transition (EMT) program. Acquisition of a mesenchymal-like phenotype renders PDAC cells more invasive and resistant to therapy-induced apoptosis. Here, we critically review seminal and recent articles on the signaling mechanisms by which each stromal element promotes EMT in PDAC. We discussed the experimental models that are currently employed and best suited to study EMT in PDAC, which are instrumental in increasing the chance of successful clinical translation.

Soluble Compounds Released by Hypoxic Stroma Confer Invasive Properties to Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma and a hypoxic microenvironment. Pancreatic stellate cells (PSC) are activated by hypoxia and promote excessive desmoplasia, further contributing to the development of hypoxia. We aimed to explore how hypoxia and stroma interact to contribute to invasive growth in PDAC. [¹⁸F]HX4 PET/CT was found to be a feasible non-invasive method to assess tumor hypoxia in 42 patients and correlated with HIF1α immunohistochemistry in matched surgical specimens. [¹⁸F]HX4 uptake and HIF1α were strong prognostic markers for overall survival. Co-culture and medium transfer experiments demonstrated that hypoxic PSCs and their supernatant induce upregulation of mesenchymal markers in tumor cells, and that hypoxia-induced stromal factors drive invasive growth in hypoxic PDACs. Through stepwise selection, stromal MMP10 was identified as the most likely candidate responsible for this. In conclusion, hypoxia-activated PSCs promote the invasiveness of PDAC through paracrine signaling. The identification of PSC-derived MMP10 may provide a lead to develop novel stroma-targeting therapies.

The Role of Dysfunctional Adipose Tissue in Pancreatic Cancer: A Molecular Perspective

Pancreatic cancer (PC) is a lethal malignancy with rising incidence and limited therapeutic options. Obesity is a well-established risk factor for PC development. Moreover, it negatively affects outcome in PC patients. Excessive fat accumulation in obese, over- and normal-weight individuals induces metabolic and inflammatory changes of adipose tissue microenvironment leading to a dysfunctional adipose “organ”. This may drive the association between abnormal fat accumulation and pancreatic cancer. In this review, we describe several molecular mechanisms that underpin this association at both local and systemic levels. We focus on the role of adipose tissue-derived circulating factors including adipokines, hormones and pro-inflammatory cytokines, as well as on the impact of the local adipose tissue in promoting PC. A discussion on potential therapeutic interventions, interfering with pro-tumorigenic effects of dysfunctional adipose tissue in PC, is included. Considering the raise of global obesity, research efforts to uncover the molecular basis of the relationship between pancreatic cancer and adipose tissue dysfunction may provide novel insights for the prevention of this deadly disease. In addition, these efforts may uncover novel targets for personalized interventional strategies aimed at improving the currently unsatisfactory PC therapeutic options.

Prognostic implications of RAS alterations in diverse malignancies and impact of targeted therapies

RAS alterations are often found in difficult-to-treat malignancies and are considered "undruggable." To better understand the clinical correlates and coaltered genes of RAS alterations, we used targeted next-generation sequencing (NGS) to analyze 1,937 patients with diverse cancers. Overall, 20.9% of cancers (405/1,937) harbored RAS alterations. Most RAS-altered cases had genomic coalterations (95.3%, median: 3, range: 0-51), often involving genes implicated in oncogenic signals: PI3K pathway (31.4% of 405 cases), cell cycle (31.1%), tyrosine kinase families (21.5%) and MAPK signaling (18.3%). Patients with RAS-altered versus wild-type RAS malignancies had significantly worse overall survival (OS; p = 0.02 [multivariate]), with KRAS alterations, in particular, showing shorter survival. Moreover, coalterations in both RAS and PI3K signaling or cell-cycle-associated genes correlated with worse OS (p = 0.004 and p < 0.0001, respectively [multivariate]). Among RAS-altered patients, MEK inhibitors alone did not impact progression-free survival (PFS), while matched targeted therapy against non-MAPK pathway coalterations alone showed a trend toward longer PFS (vs. patients who received unmatched therapy) (HR: 0.79, 95% CI: 0.61-1.03, p = 0.07). Three of nine patients (33%) given tailored combination therapies targeting both MAPK and non-MAPK pathways achieved objective responses. In conclusion, RAS alterations correlated with poor survival across cancers. The majority of RAS alterations were accompanied by coalterations impacting other oncogenic pathways. MEK inhibitors alone were ineffective against RAS-altered cancers while matched targeted therapy against coalterations alone correlated with a trend toward improved PFS. A subset of the small number of patients given MEK inhibitors plus tailored non-MAPK-targeting agents showed responses, suggesting that customized combinations warrant further investigation.

Squamous trans-differentiation of pancreatic cancer cells promotes stromal inflammation

A highly aggressive subset of pancreatic ductal adenocarcinomas undergo trans-differentiation into the squamous lineage during disease progression. Here, we investigated whether squamous trans-differentiation of human and mouse pancreatic cancer cells can influence the phenotype of non-neoplastic cells in the tumor microenvironment. Conditioned media experiments revealed that squamous pancreatic cancer cells secrete factors that recruit neutrophils and convert pancreatic stellate cells into cancer-associated fibroblasts (CAFs) that express inflammatory cytokines at high levels. We use gain- and loss-of-function approaches to show that squamous-subtype pancreatic tumor models become enriched with neutrophils and inflammatory CAFs in a p63-dependent manner. These effects occur, at least in part, through p63-mediated activation of enhancers at pro-inflammatory cytokine loci, which includes IL1A and CXCL1 as key targets. Taken together, our findings reveal enhanced tissue inflammation as a consequence of squamous trans-differentiation in pancreatic cancer, thus highlighting an instructive role of tumor cell lineage in reprogramming the stromal microenvironment.

Quantitative assessment of extracellular IL-1 regulation

IL-1 system is involved in the induction and maintenance of chronic inflammation associated with several autoimmune diseases and cancer, mainly due to its capacity to promote the secretion of inflammatory mediators. For this reason, several intracellular and extracellular mechanisms for this system have been fixed during the evolution. In spite of the large description of molecular interactions between IL-1 ligands and receptors, little is known about the relevance and limits of the extracellular regulatory mechanims in different scenarios. To tackle this problem, we developed and calibrated a mathematical model including all the known interactions between IL-1 ligands and IL-1Rs and calibrate it with experimental data of IL-1 binding to different cells. The model predicts that, independently on the IL-1Rs expression, IL-1α has more ability than IL-1β to induce IL-1 signaling, which suggests that both ligands can be equally relevant for the IL-1 related inflammation. On the other hand, at the cell level, IL-1 signaling is mainly controlled by IL-1R1 and IL-1R3 and not by IL-1R2. Moreover, the soluble form of IL-1R1 and IL-1RA have the highest capacity to prevent IL-1α while IL-1R2 and IL-1R1 and IL-1RA have a similar capacity to prevent IL-1β signaling. The soluble IL-1R3 has the lowest capacity to prevent IL-1 signaling and preferentially inhibits cells with low number of IL-1R3. In general, model predictions suggest several ways in which IL-1 controlling system may fail, developing IL-1 related inflammation.

Interleukin 1β-mediated HOXC10 Overexpression Promotes Hepatocellular Carcinoma Metastasis by Upregulating PDPK1 and VASP

Rationale: Metastasis and recurrence are the primary reasons for the high mortality rate of human hepatocellular carcinoma (HCC) patients. However, the exact mechanism underlying HCC metastasis remains unclear. The Homeobox (HOX) family proteins, which are a highly conserved transcription factor superfamily, play important roles in cancer metastasis. Here, we report a novel role of HOXC10, one of the most upregulated HOX genes in human HCC tissues, in promoting HCC metastasis.

Methods: The expression of HOXC10 and its functional targets was detected by immunohistochemistry in two independent human HCC cohorts. Luciferase reporter and chromatin immunoprecipitation assays were used to measure the transcriptional regulation of target genes by HOXC10. The effect of HOXC10-mediated invasion and metastasis were analyzed by Transwell assays and by an orthotopic metastasis model.

Results: Elevated expression of HOXC10 was positively correlated with the loss of tumor encapsulation and with higher tumor-nodule-metastasis (TNM) stage and poor prognosis in human HCC. Overexpression of HOXC10 promoted HCC metastasis by upregulating metastasis-related genes, including 3-phosphoinositide-dependent protein kinase 1 (PDPK1) and vasodilator-stimulated phosphoprotein (VASP). Knockdown of PDPK1 and VASP inhibited HOXC10-enhanced HCC metastasis, whereas upregulation of PDPK1 and VASP rescued the decreased metastasis induced by HOXC10 knockdown. Interleukin-1β (IL-1β), which is the ligand of IL-1R1, upregulated HOXC10 expression through the c-Jun NH2-terminal kinase (JNK)/c-Jun pathway. HOXC10 knockdown significantly reduced IL-1β-mediated HCC metastasis. Furthermore, Anakinra, a specific antagonist of IL-1R1, inhibited IL-1β-induced HOXC10 upregulation and HCC metastasis. In human HCC tissues, HOXC10 expression was positively correlated with PDPK1, VASP and IL-1R1 expression, and patients with positive coexpression of HOXC10/PDPK1, HOXC10/VASP or IL-1R1/HOXC10 exhibited the poorest prognosis.

Conclusions: Upregulated HOXC10 induced by IL-1β promotes HCC metastasis by transactivating PDPK1 and VASP expression. Thus, our study implicates HOXC10 as a prognostic biomarker, and targeting this pathway may be a promising therapeutic option for the clinical prevention of HCC metastasis.

IL-1 Signaling in Tumor Microenvironment

Interleukin 1 (IL-1) has long been known for its pleiotropic effects on inflammation that plays a complex, and sometimes contrasting, role in different stages of cancer development. As a major proinflammatory cytokine, IL-1β is mainly expressed by innate immune cells. IL-1α, however, is expressed by various cell types under physiological and pathological conditions. IL-1R1 is the main receptor for both ligands and is expressed by various cell types, including innate and adaptive immune cell types, epithelial cells, endothelial cells, adipocytes, chondrocytes, fibroblasts, etc. IL-1 and IL-1R1 receptor interaction leads to a set of common signaling pathways, mainly the NF-kB and MAP kinase pathways, as a result of complex positive and negative regulations. The variety of cell types with IL-1R1 expression dictates the role of IL-1 signaling at different stages of cancer, which under certain circumstances leads to contrasting roles in tumor development. Recent availability of IL-1R1 conditional knockout mouse model has made it possible to dissect the role of IL-1/IL-1R1 signaling transduction in different cell types within the tumor microenvironment. This chapter will focus on the role of IL-1/IL-1R1 in different cell types within the tumor microenvironment and discuss the potential of targeting this pathway in cancer therapy.