Interleukin 22 Signaling Regulates Acinar Cell Plasticity to Promote Pancreatic Tumor Development in Mice

The role of IL-22 in cancer

Interleukin-22, discovered in the year of 2000, is a pleiotropic Th17 cytokine from the IL-10 family of cytokines. IL-22 signals through the type 2 cytokine receptor complex IL-22R and predominantly activates STAT3. This pathway leads to the transcription of several different types of genes, giving IL-22 context-specific functions ranging from inducing antimicrobial peptide expression to target cell proliferation. In recent years, it has been shown that IL-22 is involved in the pathogenesis of neoplasia in some cancers through its pro-proliferative and anti-apoptotic effects. This review highlights studies with recent discoveries and conclusions drawn on IL-22 and its involvement and function in various cancers. Such a study may be helpful to better understand the role of IL-22 in cancer so that new treatment could be developed targeting IL-22.

The TRIM28/miR133a/CD47 axis acts as a potential therapeutic target in pancreatic necrosis by impairing efferocytosis

Efferocytosis, the clearance of apoptotic cells by macrophages, plays a crucial role in inflammatory responses and effectively prevents secondary necrosis. However, the mechanisms underlying efferocytosis in acute pancreatitis (AP) remain unclear. In this study, we demonstrated the presence of efferocytosis in injured human and mouse pancreatic tissues. We also observed significant upregulation of CD47, an efferocytosis-related the "do not eat me" molecule in injured acinar cells. Subsequently, we used CRISPR-Cas9 gene editing, anti-adeno-associated virus (AAV) gene modification, and anti-CD47 antibody to investigate the potential therapeutic role of AP. CD47 expression was negatively regulated by upstream miR133a, which is controlled by the transcription factor TRIM28. To further investigate the regulation of efferocytosis and reduction of pancreatic necrosis in AP, we used miR-133a-agomir and pancreas-specific AAV-shTRIM28 to modulate CD47 expression. Our findings confirmed that CD47-mediated efferocytosis is critical for preventing pancreatic necrosis and suggest that targeting the TRIM28-miR133a-CD47 axis is clinically relevant for the treatment of AP.

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

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

Pancreatic STAT5 activation promotes KrasG12D-induced and inflammation-induced acinar-to-ductal metaplasia and pancreatic cancer

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy because it is often diagnosed at a late-stage. Signal transducer and activator of transcription 5 (STAT5) is a transcription factor implicated in the progression of various cancer types. However, its role in KRAS-driven pancreatic tumourigenesis remains unclear.

DESIGN

We performed studies with LSL-Kras G12D; Ptf1a-Cre ERT (KCERT) mice or LSL-KrasG12D; LSL-Trp53R172H ; Pdx1-Cre (KPC) mice crossed with conditional disruption of STAT5 or completed deficiency interleukin (IL)-22. Pancreatitis was induced in mice by administration of cerulein. Pharmacological inhibition of STAT5 on PDAC prevention was studied in the orthotopic transplantation and patient-derived xenografts PDAC model, and KPC mice.

RESULTS

The expression and phosphorylation of STAT5 were higher in human PDAC samples than control samples and high levels of STAT5 in tumour cells were associated with a poorer prognosis. The loss of STAT5 in pancreatic cells substantially reduces the KRAS mutation and pancreatitis-derived acinar-to-ductal metaplasia (ADM) and PDAC lesions. Mechanistically, we discovered that STAT5 binds directly to the promoters of ADM mediators, hepatocyte nuclear factor (HNF) 1β and HNF4α. Furthermore, STAT5 plays a crucial role in maintaining energy metabolism in tumour cells during PDAC progression. IL-22 signalling induced by chronic inflammation enhances KRAS-mutant-mediated STAT5 phosphorylation. Deficiency of IL-22 signalling slowed the progression of PDAC and ablated STAT5 activation.

CONCLUSION

Collectively, our findings identified pancreatic STAT5 activation as a key downstream effector of oncogenic KRAS signalling that is critical for ADM initiation and PDAC progression, highlighting its potential therapeutic vulnerability.

Tumour-associated myeloid cells expressing IL-10R2/IL-22R1 as a potential biomarker for diagnosis and recurrence of pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a poor survival rate, largely due to the lack of early diagnosis. Although myeloid cells are crucial in the tumour microenvironment, whether their specific subset can be a biomarker of PDAC progression is unclear.

METHODS

We analysed IL-22 receptor expression in PDAC and peripheral blood. Additionally, we analysed gene expression profiles of IL-10R2+/IL-22R1+ myeloid cells and the presence of these cells using single-cell RNA sequencing and murine orthotropic PDAC models, respectively, followed by examining the immunosuppressive function of IL-10R2+/IL-22R1+ myeloid cells. Finally, the correlation between IL-10R2 expression and PDAC progression was evaluated.

RESULTS

IL-10R2+/IL-22R1+ myeloid cells were present in PDAC and peripheral blood. Blood IL-10R2+ myeloid cells displayed a gene expression signature associated with tumour-educated circulating monocytes. IL-10R2+/IL-22R1+ myeloid cells from human myeloid cell culture inhibited T cell proliferation. By mouse models for PDAC, we found a positive correlation between pancreatic tumour growth and increased blood IL-10R2+/IL-22R1+ myeloid cells. IL-10R2+/IL-22R1+ myeloid cells from an early phase of the PDAC model suppressed T cell proliferation and cytotoxicity. IL-10R2+ myeloid cells indicated tumour recurrence 130 days sooner than CA19-9 in post-pancreatectomy patients.

CONCLUSIONS

IL-10R2+/IL-22R1+ myeloid cells in the peripheral blood might be an early marker of PDAC prognosis.

Cellular collusion: cracking the code of immunosuppression and chemo resistance in PDAC

Despite the efforts, pancreatic ductal adenocarcinoma (PDAC) is still highly lethal. Therapeutic challenges reside in late diagnosis and establishment of peculiar tumor microenvironment (TME) supporting tumor outgrowth. This stromal landscape is highly heterogeneous between patients and even in the same patient. The organization of functional sub-TME with different cellular compositions provides evolutive advantages and sustains therapeutic resistance. Tumor progressively establishes a TME that can suit its own needs, including proliferation, stemness and invasion. Cancer-associated fibroblasts and immune cells, the main non-neoplastic cellular TME components, follow soluble factors-mediated neoplastic instructions and synergize to promote chemoresistance and immune surveillance destruction. Unveiling heterotypic stromal-neoplastic interactions is thus pivotal to breaking this synergism and promoting the reprogramming of the TME toward an anti-tumor milieu, improving thus the efficacy of conventional and immune-based therapies. We underscore recent advances in the characterization of immune and fibroblast stromal components supporting or dampening pancreatic cancer progression, as well as novel multi-omic technologies improving the current knowledge of PDAC biology. Finally, we put into context how the clinic will translate the acquired knowledge to design new-generation clinical trials with the final aim of improving the outcome of PDAC patients.

The role of Interleukin-22 in severe acute pancreatitis

Severe acute pancreatitis (SAP) begins with premature activation of enzymes, promoted by the immune system, triggering a potential systemic inflammatory response that leads to organ failure with increased mortality and a bleak prognosis. Interleukin-22 (IL-22) is a cytokine that may have a significant role in SAP. IL-22, a member of the IL-10 cytokine family, has garnered growing interest owing to its potential tissue-protective properties. Recently, emerging research has revealed its specific effects on pancreatic diseases, particularly SAP. This paper provides a review of the latest knowledge on the role of IL-22 and its viability as a therapeutic target in SAP.

Tumor-initiating cells establish a niche to overcome isolation stress

While the tumor microenvironment is a critical contributor to cancer progression, early steps of tumor initiation and metastasis also rely on the ability of individual tumor cells to survive and thrive at locations where tumor stroma or immune infiltration has yet to be established. In this opinion article, we use the term 'isolation stress' to broadly describe the challenges that individual tumor cells must overcome during the initiation and expansion of the primary tumor beyond permissive boundaries and metastatic spread into distant sites, including a lack of cell-cell contact, adhesion to protumor extracellular matrix proteins, and access to nutrients, oxygen, and soluble factors that support growth. In particular, we highlight the ability of solitary tumor cells to autonomously generate a specialized fibronectin-enriched extracellular matrix to create their own pericellular niche that supports tumor initiation. Cancer cells that can creatively evade the effects of isolation stress not only become more broadly stress tolerant, they also tend to show enhanced stemness, drug resistance, tumor initiation, and metastasis.

(-)-Asarinin alleviates gastric precancerous lesions by promoting mitochondrial ROS accumulation and inhibiting the STAT3 signaling pathway

BACKGROUND

(-)-Asarinin (Asarinin) is the primary component in the extract of the herb Asarum sieboldii Miq. It possesses various functions, including pain relief, anti-viral and anti-tuberculous bacilli effects, and inhibition of tumor growth. Gastric precancerous lesion (GPL) is a common but potentially carcinogenic chronic gastrointestinal disease, and its progression can lead to gastric dysfunction and cancer development. However, the protective effects of asarinin against GPL and the underlying mechanisms remain unexplored.

METHODS

A premalignant cell model (methylnitronitrosoguanidine-induced malignant transformation of human gastric epithelial cell strain, MC cells) and a GPL animal model were established and then were treated with asarinin. The cytotoxic effect of asarinin was assessed using a CCK8 assay. Detection of intracellular reactive oxygen species (ROS) using DCFH-DA. Apoptosis in MC cells was evaluated using an annexin V-FITC/PI assay. We performed western blot analysis and immunohistochemistry (IHC) to analyze relevant markers, investigating the in vitro and in vivo therapeutic effects of asarinin on GPL and its intrinsic mechanisms.

RESULTS

Our findings showed that asarinin inhibited MC cell proliferation, enhanced intracellular ROS levels, and induced cell apoptosis. Further investigations revealed that the pharmacological effects of asarinin on MC cells were blocked by the ROS scavenger N-acetylcysteine. IHC revealed a significant upregulation of phospho-signal transducer and activator of transcription 3 (p-STAT3) protein expression in human GPL tissues. In vitro, asarinin exerted its pro-apoptotic effects in MC cells by modulating the STAT3 signaling pathway. Agonists of STAT3 were able to abolish the effects of asarinin on MC cells. In vivo, asarinin induced ROS accumulation and inhibited the STAT3 pathway in gastric mucosa of mice, thereby halting and even reversing the development of GPL.

CONCLUSION

Asarinin induces apoptosis and delays the progression of GPL by promoting mitochondrial ROS production, decreasing mitochondrial membrane potential (MMP), and inhibiting the STAT3 pathway.

Molecular profile of metastasis, cell plasticity and EMT in pancreatic cancer: a pre-clinical connection to aggressiveness and drug resistance

The metastasis is a multistep process in which a small proportion of cancer cells are detached from the colony to enter into blood cells for obtaining a new place for metastasis and proliferation. The metastasis and cell plasticity are considered major causes of cancer-related deaths since they improve the malignancy of cancer cells and provide poor prognosis for patients. Furthermore, enhancement in the aggressiveness of cancer cells has been related to the development of drug resistance. Metastasis of pancreatic cancer (PC) cells has been considered one of the major causes of death in patients and their undesirable prognosis. PC is among the most malignant tumors of the gastrointestinal tract and in addition to lifestyle, smoking, and other factors, genomic changes play a key role in its progression. The stimulation of EMT in PC cells occurs as a result of changes in molecular interaction, and in addition to increasing metastasis, EMT participates in the development of chemoresistance. The epithelial, mesenchymal, and acinar cell plasticity can occur and determines the progression of PC. The major molecular pathways including STAT3, PTEN, PI3K/Akt, and Wnt participate in regulating the metastasis of PC cells. The communication in tumor microenvironment can provide by exosomes in determining PC metastasis. The components of tumor microenvironment including macrophages, neutrophils, and cancer-associated fibroblasts can modulate PC progression and the response of cancer cells to chemotherapy.

Deciphering cellular plasticity in pancreatic cancer for effective treatments

Cellular plasticity and therapy resistance are critical features of pancreatic cancer, a highly aggressive and fatal disease. The pancreas, a vital organ that produces digestive enzymes and hormones, is often affected by two main types of cancer: the pre-dominant ductal adenocarcinoma and the less common neuroendocrine tumors. These cancers are difficult to treat due to their complex biology characterized by cellular plasticity leading to therapy resistance. Cellular plasticity refers to the capability of cancer cells to change and adapt to different microenvironments within the body which includes acinar-ductal metaplasia, epithelial to mesenchymal/epigenetic/metabolic plasticity, as well as stemness. This plasticity allows heterogeneity of cancer cells, metastasis, and evasion of host's immune system and develops resistance to radiation, chemotherapy, and targeted therapy. To overcome this resistance, extensive research is ongoing exploring the intrinsic and extrinsic factors through cellular reprogramming, chemosensitization, targeting metabolic, key survival pathways, etc. In this review, we discussed the mechanisms of cellular plasticity involving cellular adaptation and tumor microenvironment and provided a comprehensive understanding of its role in therapy resistance and ways to overcome it.

Prognostic Value of Circulating Cell-Free DNA Concentration and Neutrophil-to-Lymphocyte Ratio in Patients with Pancreatic Ductal Adenocarcinoma: A Prospective Cohort Study

Circulating cell-free DNA (ccfDNA) quantity correlates with the clinical characteristics and prognosis of various cancer types. We investigated whether ccfDNA levels and the neutrophil-to-lymphocyte ratio (NLR) have prognostic value in patients with pancreatic ductal adenocarcinoma (PDAC). Peripheral blood was collected from 82 patients with PDAC prior to any diagnostic procedure or the administration of chemotherapy. Plasma DNA was isolated, and ccfDNA concentration and NLR were determined. We found that ccfDNA levels were correlated with age and tumor burden. Moreover, higher values of NLR (≥3.31) were linked with worse overall survival (OS) (4 vs. 10 months; log rank p = 0.011), and an elevated ccfDNA concentration (≥25.79 ng/mL) was strongly associated with shorter OS (4 vs. 8 months; log rank p = 0.009). According to the results of the multivariable Cox regression analysis, the baseline concentration of ccfDNA was an independent prognostic factor for OS (HR 0.45, 95% CI 0.21-0.97, p = 0.041). Furthermore, the combination of ccfDNA levels with NLR greatly enhanced the prognostic accuracy of PDAC patients. Our study demonstrates that ccfDNA concentration and NLR are independent predictors of survival in PDAC. Subsequent studies should validate this combination as a prognostic indicator in PDAC patients and assess its utility for guiding therapeutic decisions.

Recent advances in drug delivery and targeting for the treatment of pancreatic cancer

Despite significant treatment efforts, pancreatic ductal adenocarcinoma (PDAC), the deadliest solid tumor, is still incurable in the preclinical stages due to multifacet stroma, dense desmoplasia, and immune regression. Additionally, tumor heterogeneity and metabolic changes are linked to low grade clinical translational outcomes, which has prompted the investigation of the mechanisms underlying chemoresistance and the creation of effective treatment approaches by selectively targeting genetic pathways. Since targeting upstream molecules in first-line oncogenic signaling pathways typically has little clinical impact, downstream signaling pathways have instead been targeted in both preclinical and clinical studies. In this review, we discuss how the complexity of various tumor microenvironment (TME) components and the oncogenic signaling pathways that they are connected to actively contribute to the development and spread of PDAC, as well as the ways that recent therapeutic approaches have been targeted to restore it. We also illustrate how many endogenous stimuli-responsive linker-based nanocarriers have recently been developed for the specific targeting of distinct oncogenes and their downstream signaling cascades as well as their ongoing clinical trials. We also discuss the present challenges, prospects, and difficulties in the development of first-line oncogene-targeting medicines for the treatment of pancreatic cancer patients.

The oncogenic mechanisms of the Janus kinase-signal transducer and activator of transcription pathway in digestive tract tumors

Digestive tract tumors are heterogeneous and involve the dysregulation of multiple signaling pathways. The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway plays a notable role in the oncogenesis of digestive tract tumors. Typically activated by pro-inflammatory cytokines, it regulates important biological processes, such as cell growth, differentiation, apoptosis, immune responses, and inflammation. The aberrant activation of this pathway manifests in different forms, including mutations in JAKs, overexpression of cytokine receptors, and sustained STAT activation, and contributes to promoting the malignant characteristics of cancer cells, including uncontrolled proliferation, resistance to apoptosis, enhanced invasion and metastasis, angiogenesis, acquisition of stem-like properties, and drug resistance. Numerous studies have shown that aberrant activation of the JAK-STAT pathway is closely related to the development and progression of digestive tract tumors, contributing to tumor survival, angiogenesis, changes in the tumor microenvironment, and even immune escape processes. In addition, this signaling pathway also affects the sensitivity of digestive tract tumors to chemotherapy and targeted therapy. Therefore, it is crucial to comprehensively understand the oncogenic mechanisms underlying the JAK-STAT pathway in order to develop effective therapeutic strategies against digestive tract tumors. Currently, several JAK-STAT inhibitors are undergoing clinical and preclinical trials as potential treatments for various human diseases. However, further investigation is required to determine the role of this pathway, as well as the effectiveness and safety of its inhibitors, especially in the context of digestive tract tumors. In this review, we provide an overview of the structure, classic activation, and negative regulation of the JAK-STAT pathway. Furthermore, we discuss the pathogenic mechanisms of JAK-STAT signaling in different digestive tract tumors, with the aim of identifying potential novel therapeutic targets. Video Abstract.

Pro-osteogenic role of interleukin-22 in calcific aortic valve disease

BACKGROUND AND AIMS

Although calcific aortic valve disease (CAVD) is a common valvular disease among elderly populations and its incidence has markedly increased in recent decades, the pathogenesis of CAVD remains unclear. In this study, we explored the potential role of interleukin (IL)-22 and the underlying molecular mechanism in CAVD.

METHODS AND RESULTS

Our results showed that IL-22 was upregulated in calcific aortic valves from CAVD patients, and its main sources were CD3+ T cells and CD68+ macrophages. Human aortic valve interstitial cells (VICs) expressed the IL-22-specific receptor IL-22R1, and IL-22R1 expression also was elevated in calcified valves. Treatment of cultured human VICs with recombinant human IL-22 resulted in markedly increased expression of osteogenic proteins Runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP), as well as increased matrix calcium deposition. Moreover, siRNA silencing of IL-22R1 blocked the pro-osteogenic effect of IL-22 in VICs. In IL-22-treated VICs, we also observed increased phosphorylation of JAK3 and STAT3 and nuclear translocation of STAT3. Pretreatment with a specific JAK3 inhibitor, WHIP-154, or siRNA knockout of STAT3 effectively mitigated the IL-22-induced osteoblastic trans-differentiation of human VICs.

CONCLUSIONS

Together, these data indicate that IL-22 promotes osteogenic differentiation of VICs by activating JAK3/STAT3 signaling. Based on our results demonstrating a pro-osteogenic role of IL-22 in human aortic valves, pharmacological inhibition of IL-22 signaling may represent a potential strategy for alleviating CAVD.

Targeted Protein Degradation: Principles, Strategies, and Applications

Protein degradation is a general process to maintain cell homeostasis. The intracellular protein quality control system mainly includes the ubiquitin-proteasome system and the lysosome pathway. Inspired by the physiological process, strategies to degrade specific proteins have developed, which emerge as potent and effective tools in biological research and drug discovery. This review focuses on recent advances in targeted protein degradation techniques, summarizing the principles, advantages, and challenges. Moreover, the potential applications and future direction in biological science and clinics are also discussed.

The role of epithelial-mesenchymal transition and autophagy in pancreatic ductal adenocarcinoma invasion

Of all pancreatic cancer (PC) cases, approximately 90% are pancreatic ductal adenocarcinoma (PDAC), which progress rapidly due to its high degree of invasiveness and high metastatic potential. Epithelial-mesenchymal transition (EMT) is a prerequisite for cancer cell invasion and spread, and it is mediated by the specific cellular behaviors and the tumor microenvironment. Autophagy has long been a target of cancer therapy, and it has been considered to play a dual and contradictory role, particularly regarding EMT-mediated PDAC invasion. This review discusses the characteristics and the biological role of EMT and autophagy from a cellular perspective, explaining invasion as a survival behavior of PDAC, with the aim of providing novel insights into targeting EMT and autophagy to overcome PDAC invasion.

Acinar-to-Ductal Metaplasia (ADM): On the Road to Pancreatic Intraepithelial Neoplasia (PanIN) and Pancreatic Cancer

Adult pancreatic acinar cells show high plasticity allowing them to change in their differentiation commitment. Pancreatic acinar-to-ductal metaplasia (ADM) is a cellular process in which the differentiated pancreatic acinar cells transform into duct-like cells. This process can occur as a result of cellular injury or inflammation in the pancreas. While ADM is a reversible process allowing pancreatic acinar regeneration, persistent inflammation or injury can lead to the development of pancreatic intraepithelial neoplasia (PanIN), which is a common precancerous lesion that precedes pancreatic ductal adenocarcinoma (PDAC). Several factors can contribute to the development of ADM and PanIN, including environmental factors such as obesity, chronic inflammation and genetic mutations. ADM is driven by extrinsic and intrinsic signaling. Here, we review the current knowledge on the cellular and molecular biology of ADM. Understanding the cellular and molecular mechanisms underlying ADM is critical for the development of new therapeutic strategies for pancreatitis and PDAC. Identifying the intermediate states and key molecules that regulate ADM initiation, maintenance and progression may help the development of novel preventive strategies for PDAC.

A network pharmacology-based investigation of emodin against pancreatic adenocarcinoma

Pancreatic adenocarcinoma (PAAD) is one of the most common malignancies worldwide with an increasing incidence and poor outcome due to the lack of effective diagnostic and treatment methods. Emerging evidence implicates that emodin displays extensive spectrum anticancer properties. Differential expression genes in PAAD patients were analyzed by Gene Expression Profiling Interactive Analysis (GEPIA) website, and the targets of emodin were obtained via Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. Subsequently, enrichment analyses were performed using R software. A protein-protein interaction (PPI) network was constructed by STRING database and Cytoscape software was used to identify the hub genes. Prognostic value and immune infiltration landscapes were explored through Kaplan-Meier plotter (KM plotter) website and the Single-Sample Gene Set Enrichment Analysis package of R. Finally, molecular docking was used to computationally verify the interaction of ligand and receptor proteins. A total of 9191 genes were significantly differentially expressed in PAAD patients and 34 potential targets of emodin were obtained. Intersections of the 2 groups were considered as potential targets of emodin against PAAD. Functional enrichment analyses illustrated that these potential targets were linked to numerous pathological processes. Hub genes identified through PPI networks were correlated with poor prognosis and infiltration level of different immune cells in PAAD patients. Perhaps emodin interacted with the key molecules and regulate the activity of them. We revealed the inherent mechanism of emodin against PAAD with the aid of network pharmacology, which provided reliable evidence and a novel guideline for clinical treatment.

Pancreatic cancer: Advances and challenges

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancers. Significant efforts have largely defined major genetic factors driving PDAC pathogenesis and progression. Pancreatic tumors are characterized by a complex microenvironment that orchestrates metabolic alterations and supports a milieu of interactions among various cell types within this niche. In this review, we highlight the foundational studies that have driven our understanding of these processes. We further discuss the recent technological advances that continue to expand our understanding of PDAC complexity. We posit that the clinical translation of these research endeavors will enhance the currently dismal survival rate of this recalcitrant disease.

The Cell Biology of Metastatic Invasion in Pancreatic Cancer: Updates and Mechanistic Insights

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related mortality worldwide. This is largely due to the lack of routine screening protocols, an absence of symptoms in early-stage disease leading to late detection, and a paucity of effective treatment options. Critically, the majority of patients either present with metastatic disease or rapidly develop metastatic disease. Thus, there is an urgent need to deepen our understanding of metastasis in PDAC. During metastasis, tumor cells escape from the primary tumor, enter the circulation, and travel to a distant site to form a secondary tumor. In order to accomplish this relatively rare event, tumor cells develop an enhanced ability to detach from the primary tumor, migrate into the surrounding matrix, and invade across the basement membrane. In addition, cancer cells interact with the various cell types and matrix proteins that comprise the tumor microenvironment, with some of these factors working to promote metastasis and others working to suppress it. In PDAC, many of these processes are not well understood. The purpose of this review is to highlight recent advances in the cell biology of the early steps of the metastatic cascade in pancreatic cancer. Specifically, we will examine the regulation of epithelial-to-mesenchymal transition (EMT) in PDAC and its requirement for metastasis, summarize our understanding of how PDAC cells invade and degrade the surrounding matrix, and discuss how migration and adhesion dynamics are regulated in PDAC to optimize cancer cell motility. In addition, the role of the tumor microenvironment in PDAC will also be discussed for each of these invasive processes.

Mechanisms of obesity- and diabetes mellitus-related pancreatic carcinogenesis: a comprehensive and systematic review

Research on obesity- and diabetes mellitus (DM)-related carcinogenesis has expanded exponentially since these two diseases were recognized as important risk factors for cancers. The growing interest in this area is prominently actuated by the increasing obesity and DM prevalence, which is partially responsible for the slight but constant increase in pancreatic cancer (PC) occurrence. PC is a highly lethal malignancy characterized by its insidious symptoms, delayed diagnosis, and devastating prognosis. The intricate process of obesity and DM promoting pancreatic carcinogenesis involves their local impact on the pancreas and concurrent whole-body systemic changes that are suitable for cancer initiation. The main mechanisms involved in this process include the excessive accumulation of various nutrients and metabolites promoting carcinogenesis directly while also aggravating mutagenic and carcinogenic metabolic disorders by affecting multiple pathways. Detrimental alterations in gastrointestinal and sex hormone levels and microbiome dysfunction further compromise immunometabolic regulation and contribute to the establishment of an immunosuppressive tumor microenvironment (TME) for carcinogenesis, which can be exacerbated by several crucial pathophysiological processes and TME components, such as autophagy, endoplasmic reticulum stress, oxidative stress, epithelial-mesenchymal transition, and exosome secretion. This review provides a comprehensive and critical analysis of the immunometabolic mechanisms of obesity- and DM-related pancreatic carcinogenesis and dissects how metabolic disorders impair anticancer immunity and influence pathophysiological processes to favor cancer initiation.

Comprehensive analysis of LILR family genes expression and tumour-infiltrating immune cells in early-stage pancreatic ductal adenocarcinoma

Leucocyte immunoglobulin-like receptors (LILRs) are closely related to tumourigenesis, but their clinical value in early-stage pancreatic ductal adenocarcinoma (PDAC) after pancreaticoduodenectomy remains unknown. Kaplan-Meier and Cox proportional hazards regression models is used to investigate the association between LILR expression and prognosis in tumour biopsies and peripheral blood mononuclear cells. Risk score was calculated for each patient based on the prognostic model. DAVID, STRING, GeneMANIA, and GSEA were used to conduct pathway and functional analyses. The CIBERSORT algorithm is used to analyse tumour-infiltrating immune cells. Survival analysis showed that high levels of LILRA4 (p = 0.006) and LILRB4 (p = 0.04) were significantly associated with better overall survival. High levels of LILRA2 (p = 0.008) and LILRB4 (p = 0.038) were significantly associated with better relapse-free survival. JAK-STAT signalling pathway, regulation of T cell activation, regulation of the immune effector process, and tumour necrosis factor superfamily cytokine production were involved in molecular mechanisms that affected poor prognoses in the high-risk group in GSEA. CIBERSORT demonstrated that the high-risk group had significantly higher infiltrating fraction of memory-activated CD4 T cells and activated NK cells and lower fraction of resting dendritic cells and neutrophils. LILRB4 plays crucial roles in affecting the clinical outcomes of early-stage PDAC.

T cell-derived interleukin-22 drives the expression of CD155 by cancer cells to suppress NK cell function and promote metastasis

Although T cells can exert potent anti-tumor immunity, a subset of T helper (Th) cells producing interleukin-22 (IL-22) in breast and lung tumors is linked to dismal patient outcome. Here, we examined the mechanisms whereby these T cells contribute to disease. In murine models of lung and breast cancer, constitutional and T cell-specific deletion of Il22 reduced metastases without affecting primary tumor growth. Deletion of the IL-22 receptor on cancer cells decreases metastasis to a degree similar to that seen in IL-22-deficient mice. IL-22 induced high expression of CD155, which bound to the activating receptor CD226 on NK cells. Excessive activation led to decreased amounts of CD226 and functionally impaired NK cells, which elevated the metastatic burden. IL-22 signaling was also associated with CD155 expression in human datasets and with poor patient outcomes. Taken together, our findings reveal an immunosuppressive circuit activated by T cell-derived IL-22 that promotes lung metastasis.

The STAT family: Key transcription factors mediating crosstalk between cancer stem cells and tumor immune microenvironment

Signal transducer and activator of transcription (STAT) proteins compose a family of transcription factors critical for cancer stem cells (CSCs), and they are involved in maintaining stemness properties, enhancing cell proliferation, and promoting metastasis. Recent studies suggest that STAT proteins engage in reciprocal communication between CSCs and infiltrate immune cell populations in the tumor microenvironment (TME). Emerging evidence has substantiated the influence of immune cells, including macrophages, myeloid-derived suppressor cells, and T cells, on CSC survival through the regulation of STAT signaling. Conversely, dysregulation of STATs in CSCs or immune cells contributes to the establishment of an immunosuppressive TME. Thus, STAT proteins are promising therapeutic targets for cancer treatment, especially when used in combination with immunotherapy. From this perspective, we discuss the complex roles of STATs in CSCs and highlight their functions in the crosstalk between CSCs and the immune microenvironment. Finally, cutting-edge clinical trial progress with STAT signaling inhibitors is summarized.

The Sag-Shoc2 axis regulates conversion of mPanINs to cystic lesions in Kras pancreatic tumor model

SAG/RBX2 is an E3 ligase, whereas SHOC2 is a RAS-RAF positive regulator. In this study, we address how Sag-Shoc2 crosstalk regulates pancreatic tumorigenesis induced by Kras^G12D. Sag deletion increases the size of pancreas and causes the conversion of murine pancreatic intraepithelial neoplasms (mPanINs) to neoplastic cystic lesions with a mechanism involving Shoc2 accumulation, suggesting that Sag determines the pathological process via targeting Shoc2. Shoc2 deletion significantly inhibits pancreas growth, mPanIN formation, and acinar cell transdifferentiation, indicating that Shoc2 is essential for Kras^G12D-induced pancreatic tumorigenesis. Likewise, in a primary acinar 3D culture, Sag deletion inhibits acinar-to-ductal transdifferentiation, while Shoc2 deletion significantly reduces the duct-like structures. Mechanistically, SAG is an E3 ligase that targets SHOC2 for degradation to affect both Mapk and mTorc1 pathways. Shoc2 deletion completely rescues the phenotype of neoplastic cystic lesions induced by Sag deletion, indicating physiological relevance of the Sag-Shoc2 crosstalk. Thus, the Sag-Shoc2 axis specifies the pancreatic tumor types induced by Kras^G12D.

Prognostic value of tumor-associated N1/N2 neutrophil plasticity in patients following radical resection of pancreas ductal adenocarcinoma

BACKGROUND

As an integral part of the tumor microenvironment (TME), tumor-associated neutrophils play a crucial role in tumor development. The objective of this study was to investigate the plasticity of tumor-associated N1 and N2 neutrophils in the TME of pancreatic ductal adenocarcinoma (PDAC), along with its impact on survival and association with immune infiltrations.

METHODS

The primary and validation cohorts including 90 radical resection patients from September 2012 to May 2016 and 29 radical resection patients from September 2018 to October 2019, respectively, with complete survival data, were enrolled. Immunofluorescence staining was used to identify tumor-associated N1 and N2 neutrophils, and the N1/N2 ratio was used to evaluate N1 and N2 plasticity. Thereafter, the association between tumor-associated N1/N2 neutrophil plasticity, clinical features, and immune infiltrations was investigated.

RESULTS

There was a significant increase in tumor-associated N2 neutrophils compared with tumor-associated N1 neutrophils. Low N1/N2 ratios were associated with the poorer differentiation of tumors, easier lymph node metastases, and a higher TNM stage. The median overall survival (OS) and recurrence-free survival (RFS) of the high tumor-associated N1 neutrophil group were significantly longer than those of the low group, while the tumor-associated N2 neutrophils played an opposite role. The multivariable analysis revealed that a high N1/N2 ratio was a significant prognostic indicator for OS and RFS. In addition, tumor-associated N1/N2 neutrophils showed an opposite correlation with tumor-infiltrating CD8⁺ T cells and Tregs.

CONCLUSION

The plasticity of tumor-associated N1/N2 neutrophils was identified as a crucial prognostic indicator that might reflect the TME and immune escape in patients with PDAC. On further investigation and validation, our findings may be used to further stratify patients with varying prognoses to optimize treatment.

Role of Up-Regulated Transmembrane Channel-Like Protein 5 in Pancreatic Adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma (PAAD) is a malignant tumor responsible for a heavy disease burden. Previously, only one pan-cancer study of Transmembrane channel-like protein 5 (TMC5) showed that TMC5 was highly expressed in PAAD, but the results lacked comprehensive verification, and the mechanism of TMC5 in PAAD was still unclear.

METHODS

For exploring the expression and clinical value of TMC5 in PAAD better, we adopted a comprehensive evaluation method, using internal immunohistochemistry (IHC) data combined with microarray and RNA-sequencing data collected from public databases. The single cell RNA-sequencing (scRNA-seq) data were exploited to explore the TMC5 expression in cell populations and intercellular communication. The potential mechanism of TMC5 in PAAD was analyzed from the aspects of immune infiltration, transcriptional regulation, function and pathway enrichment.

RESULTS

Our IHC data includes 148 PAAD samples and 19 non-PAAD samples, along with the available microarray and RNA-sequencing data (1166 PAAD samples, 704 non-PAAD samples). The comprehensive evaluation results showed that TMC5 was evidently up-regulated in PAAD (SMD = 1.17). Further analysis showed that TMC5 was over-expressed in cancerous epithelial cells. Furthermore, TMC5 was up-regulated in more advanced tumor T and N stages. Interestingly, we found that STAT3 as an immune marker of Th17 cells was not only positively correlated with TMC5 and up-regulated in PAAD tissues, but also the major predicted TMC5 transcription regulator. Moreover, STAT3 was involved in cancer pathway of PAAD.

CONCLUSION

Up-regulated TMC5 indicates advanced tumor stage in PAAD patients, and its role in promoting PAAD development may be regulated by STAT3.

Regulation of Tumor and Metastasis Initiation by Chemokine Receptors

Tumor-initiating cells (TICs) are a rare sub-population of cells within the bulk of a tumor that are major contributors to tumor initiation, metastasis, and chemoresistance. TICs have a stem-cell-like phenotype that is dictated by the expression of master regulator transcription factors, including OCT4, NANOG, and SOX2. These transcription factors are expressed via activation of multiple signaling pathways that drive cancer initiation and progression. Importantly, these same signaling pathways can be activated by select chemokine receptors. Chemokine receptors are increasingly being revealed as major drivers of the TIC phenotype, as their signaling can lead to activation of stemness-controlling transcription factors. Additionally, the cell surface expression of chemokine receptors provides a unique therapeutic target to disrupt signaling pathways that control the expression of master regulator transcription factors and the TIC phenotype. This review summarizes the master regulator transcription factors known to dictate the TIC phenotype, along with the complex signaling pathways that can mediate their expression and the chemokine receptors that are most upstream of this phenotype.

Pharmacological inhibition and reversal of pancreatic acinar ductal metaplasia

Pancreatic acinar cells display a remarkable degree of plasticity and can dedifferentiate into ductal-like progenitor cells by a process known as acinar ductal metaplasia (ADM). ADM is believed to be one of the earliest precursor lesions toward the development of pancreatic ductal adenocarcinoma and maintaining the pancreatic acinar cell phenotype suppresses tumor formation. The effects of a novel pStat3 inhibitor (LLL12B) and the histone deacetylase (HDAC) inhibitor trichostatin A (TSA) were investigated using 3-D cultures from p48Cre/+ and p48Cre/+LSL-KrasG12D/+ (KC) mice. LLL12B and TSA inhibited ADM in both KC and p48Cre/+ mouse pancreatic organoids. Furthermore, treatment with LLL12B or TSA on dedifferentiated acini from p48Cre/+ and KC mice that had undergone ADM produced morphologic and gene expression changes that suggest a reversal of ADM. Validation experiments using qRT-PCR (p48Cre/+ and KC) and RNA sequencing (KC) of the LLL12B and TSA treated cultures showed that the ADM reversal was more robust for the TSA treatments. Pathway analysis showed that TSA inhibited Spink1 and PI3K/AKT signaling during ADM reversal. The ability of TSA to reverse ADM was also observed in primary human acinar cultures. We report that pStat3 and HDAC inhibition can attenuate ADM in vitro and reverse ADM in the context of wild-type Kras. Our findings suggest that pharmacological inhibition or reversal of pancreatic ADM represents a potential therapeutic strategy for blocking aberrant ductal reprogramming of acinar cells.

Clinical significance of pancreatic ductal metaplasia

Pancreatic ductal metaplasia (PDM) is the stepwise replacement of differentiated somatic cells with ductal or ductal-like cells in the pancreas. PDM is usually triggered by cellular and environmental insults. PDM development may involve all cell lineages of the pancreas, and acinar cells with the highest plasticity are the major source of PDM. Pancreatic progenitor cells are also involved as cells of origin or transitional intermediates. PDM is heterogeneous at the histological, cellular, and molecular levels and only certain subsets of PDM develop further into pancreatic intraepithelial neoplasia (PanIN) and then pancreatic ductal adenocarcinoma (PDAC). The formation and evolution of PDM is regulated at the cellular and molecular levels through a complex network of signaling pathways. The key molecular mechanisms that drive PDM formation and its progression into PanIN/PDAC remain unclear, but represent key targets for reversing or inhibiting PDM. Alternatively, PDM could be a source of pancreas regeneration, including both exocrine and endocrine components. Cellular aging and apoptosis are obstacles to PDM-to-PanIN progression or pancreas regeneration. Functional identification of the cellular and molecular events driving senescence and apoptosis in PDM and its progression would help not only to restrict the development of PDM into PanIN/PDAC, but may also facilitate pancreatic regeneration. This review systematically assesses recent advances in the understanding of PDM physiology and pathology, with a focus on its implications for enhancing regeneration and prevention of cancer. © 2022 The Pathological Society of Great Britain and Ireland.

Obesity and Pancreatic Cancer: Recent Progress in Epidemiology, Mechanisms and Bariatric Surgery

More than 30% of people in the United States (US) are classified as obese, and over 50% are considered significantly overweight. Importantly, obesity is a risk factor not only for the development of metabolic syndrome but also for many cancers, including pancreatic ductal adenocarcinoma (PDAC). PDAC is the third leading cause of cancer-related death, and 5-year survival of PDAC remains around 9% in the U.S. Obesity is a known risk factor for PDAC. Metabolic control and bariatric surgery, which is an effective treatment for severe obesity and allows massive weight loss, have been shown to reduce the risk of PDAC. It is therefore clear that elucidating the connection between obesity and PDAC is important for the identification of a novel marker and/or intervention point for obesity-related PDAC risk. In this review, we discussed recent progress in obesity-related PDAC in epidemiology, mechanisms, and potential cancer prevention effects of interventions, including bariatric surgery with preclinical and clinical studies.

Epithelial–mesenchymal transition: The history, regulatory mechanism, and cancer therapeutic opportunities

Epithelial–mesenchymal transition (EMT) is a program wherein epithelial cells lose their junctions and polarity while acquiring mesenchymal properties and invasive ability. Originally defined as an embryogenesis event, EMT has been recognized as a crucial process in tumor progression. During EMT, cell–cell junctions and cell–matrix attachments are disrupted, and the cytoskeleton is remodeled to enhance mobility of cells. This transition of phenotype is largely driven by a group of key transcription factors, typically Snail, Twist, and ZEB, through epigenetic repression of epithelial markers, transcriptional activation of matrix metalloproteinases, and reorganization of cytoskeleton. Mechanistically, EMT is orchestrated by multiple pathways, especially those involved in embryogenesis such as TGFβ, Wnt, Hedgehog, and Hippo, suggesting EMT as an intrinsic link between embryonic development and cancer progression. In addition, redox signaling has also emerged as critical EMT modulator. EMT confers cancer cells with increased metastatic potential and drug resistant capacity, which accounts for tumor recurrence in most clinic cases. Thus, targeting EMT can be a therapeutic option providing a chance of cure for cancer patients. Here, we introduce a brief history of EMT and summarize recent advances in understanding EMT mechanisms, as well as highlighting the therapeutic opportunities by targeting EMT in cancer treatment.

Molecular signaling in pancreatic ductal metaplasia: emerging biomarkers for detection and intervention of early pancreatic cancer

Pancreatic ductal metaplasia (PDM) is the transformation of potentially various types of cells in the pancreas into ductal or ductal-like cells, which eventually replace the existing differentiated somatic cell type(s). PDM is usually triggered by and manifests its ability to adapt to environmental stimuli and genetic insults. The development of PDM to atypical hyperplasia or dysplasia is an important risk factor for pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDA). Recent studies using genetically engineered mouse models, cell lineage tracing, single-cell sequencing and others have unraveled novel cellular and molecular insights in PDM formation and evolution. Those novel findings help better understand the cellular origins and functional significance of PDM and its regulation at cellular and molecular levels. Given that PDM represents the earliest pathological changes in PDA initiation and development, translational studies are beginning to define PDM-associated cell and molecular biomarkers that can be used to screen and detect early PDA and to enable its effective intervention, thereby truly and significantly reducing the dreadful mortality rate of PDA. This review will describe recent advances in the understanding of PDM biology with a focus on its underlying cellular and molecular mechanisms, and in biomarker discovery with clinical implications for the management of pancreatic regeneration and tumorigenesis.

Colonic interleukin-22 protects intestinal mucosal barrier and microbiota abundance in severe acute pancreatitis

Intestinal barrier dysfunction plays a critical role in the pathophysiology of many diseases including severe acute pancreatitis (SAP). Interleukin-22 (IL-22) is a critical regulator of intestinal epithelial homeostasis. However, the mechanism, origin site, and characteristics of IL-22 in the intestinal barrier dysfunction remains elusive. Studies were conducted in patients with SAP and SAP mice model. SAP mice model was induced by intraductal infusion of 5% taurocholic acid. The level and source of IL-22 were analyzed by flow cytometry. The effect of IL-22 in SAP-associated intestinal injury were examined through knockout of IL-22 (IL-22-/- ) or administration of recombinant IL-22 (rIL-22). IL-22 increased in the early phase of SAP but declined more quickly than that of proinflammatory cytokines, such as IL-6 and TNF-α. CD177+ neutrophils contributed to IL-22 expression in SAP. IL-22 was activated in the colon rather than the small intestine during SAP. Deletion of IL-22 worse the severity of colonic injury, whereas administration of rIL-22 reduced colonic injury. Mechanistically, IL-22 ameliorates the intestinal barrier dysfunction in SAP through decreasing colonic mucosal permeability, upregulation of E-cadherin and ZO-1 expression, activation of pSTAT3/Reg3 pathway and restoration of fecal microbiota abundance. This study revealing that early decreased colonic IL-22 aggravates intestinal mucosal barrier dysfunction and microbiota dysbiosis in SAP. Colonic IL-22 is likely a promising treating target in the early phase of SAP management. Research in context Evidence before this study Intestinal barrier dysfunction plays a critical role in the pathophysiology of severe acute pancreatitis (SAP). Interleukin-22 (IL-22) is a critical regulator of intestinal epithelial homeostasis. However, the mechanism, origin site and characteristics of IL-22 in the intestinal barrier dysfunction remains elusive. Added value of this study Firstly, we determined the dynamic expression profile of IL-22 in SAP and found that IL-22 was mostly activated in the pancreas and colon and decreased earlier than proinflammatory cytokines. CD177+ neutrophils contributed to IL-22 expression in SAP. Furthermore, we found that IL-22 ameliorates intestinal barrier dysfunction in SAP through decreasing colonic mucosal permeability, upregulation of E-cadherin and ZO-1 expression, activation of pSTAT3/Reg3 pathway and restoration of fecal microbiota abundance. Implications of all the available evidence This study highlights the role of colonic injury and colonic IL-22 in SAP. IL-22 is likely a promising treating target in the early phase of SAP management.

Acinar to ductal cell trans-differentiation: A prelude to dysplasia and pancreatic ductal adenocarcinoma

Pancreatic cancer (PC) is the deadliest neoplastic epithelial malignancies and is projected to be the second leading cause of cancer-related mortality by 2024. Five years overall survival being ~10%, mortality and incidence rates are disturbing. Acinar to ductal cell metaplasia (ADM) encompasses cellular reprogramming and phenotypic switch-over, making it a cardinal event in tumor initiation. Differential cues and varied regulatory factors drive synchronous functions of metaplastic cell populations leading to multiple cell fates and physiological outcomes. ADM is a precursor for developing early pre-neoplastic lesions further progressing into PC due to oncogenic signaling. Hence delineating molecular events guiding tumor initiation may provide cues for regenerative medicine and precision onco-medicine. Therefore, understanding PC pathogenesis and early diagnosis are crucial. We hereby provide a timely overview of the current progress in this direction and future perspectives we foresee unfolding in the best interest of patient well-being and better clinical management of PC.

Rationalizing heptadecaphobia: TH 17 cells and associated cytokines in cancer and metastasis

Cancer is one of the leading causes of death worldwide. When cancer patients are diagnosed with metastasis, meaning that the primary tumor has spread to at least one different site, their life expectancy decreases dramatically. In the past decade, the immune system´s role in fighting cancer and metastasis has been studied extensively. Importantly, immune cells and inflammatory reactions generate potent antitumor responses but also contribute to tumor development. However, the molecular and cellular mechanisms underlying this dichotomic interaction between the immune system and cancer are still poorly understood. Recently, a spotlight has been cast on the distinct subsets of immune cells and their derived cytokines since evidence has implicated their crucial impact on cancer development. T helper 17 cell (TH 17) cells, which express the master transcriptional factor Retinoic acid-receptor-related orphan receptor gamma t, are among these critical cell subsets and are defined by their production of type 3 cytokines, such as IL-17A, IL-17F, and IL-22. Depending on the tumor microenvironment, these cytokines can also be produced by other immune cell sources, such as T cytotoxic 17 cell, innate lymphoid cells, NKT cells, or γδ T cells. To date, a lot of data have been collected describing the divergent functions of IL-17A, IL-17F, and IL-22 in malignancies. In this comprehensive review, we discuss the role of these TH 17- and non-TH 17-derived type 3 cytokines in different tumor entities. Furthermore, we will provide a structured insight into the strict regulation and subsequent downstream mechanisms of these cytokines in cancer and metastasis.

Common Pathophysiology in Cancer, Atrial Fibrillation, Atherosclerosis, and Thrombosis: JACC: CardioOncology State-of-the-Art Review

Cardiovascular disease and cancer are the 2 leading causes of death worldwide. Emerging evidence suggests common mechanisms between cancer and cardiovascular disease, including atrial fibrillation and atherosclerosis. With advances in cancer therapies, screening, and diagnostics, cancer-specific survival and outcomes have improved. This increase in survival has led to the coincidence of cardiovascular disease, including atrial fibrillation and atherosclerosis, as patients with cancer live longer. Additionally, cancer and cardiovascular disease share several risk factors and underlying pathophysiologic mechanisms, including inflammation, cancer-related factors including treatment effects, and alterations in platelet function. Patients with cancer are at increased risk for bleeding and thrombosis compared with the general population. Although optimal antithrombotic therapy, including agent choice and duration, has been extensively studied in the general population, this area remains understudied in patients with cancer despite their altered thrombotic and bleeding risk. Future investigation, including incorporation of cancer-specific characteristics to traditional thrombotic and bleeding risk scores, clinical trials in the cancer population, and the development of novel antithrombotic and anti-inflammatory strategies on the basis of shared pathophysiologic mechanisms, is warranted to improve outcomes in this patient population.

Epithelial to Mesenchymal Transition: Key Regulator of Pancreatic Ductal Adenocarcinoma Progression and Chemoresistance

Simple Summary

Pancreatic ductal adenocarcinoma’s (PDAC) dismal prognosis is associated with its aggressive biological behavior and resistance to chemotherapy. Epithelial to mesenchymal transition (EMT) has been recognized as a key driver of PDAC progression and development of drug resistance. EMT is a transient and reversible process leading to transdifferentiation of epithelial cells into a more mesenchymal phenotype. It is regulated by multiple signaling pathways that control the activity of a transcription factors network. Activation of EMT in pre-invasive stages of PDAC has been accused for early dissemination. Furthermore, it contributes to the development of intratumoral heterogeneity and drug resistance. This review summarizes the available data regarding signaling networks regulating EMT and describes the integral role of EMT in different aspects of PDAC pathogenesis.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies, characterized by aggressive biological behavior and a lack of response to currently available chemotherapy. Emerging evidence has identified epithelial to mesenchymal transition (EMT) as a key driver of PDAC progression and a central regulator in the development of drug resistance. EMT is a reversible transdifferentiation process controlled by complex interactions between multiple signaling pathways such as TGFb, Wnt, and Notch, which converge to a network of specific transcription factors. Activation of EMT transcriptional reprogramming converts cancer cells of epithelial differentiation into a more mesenchymal phenotypic state. EMT occurrence in pre-invasive pancreatic lesions has been implicated in early PDAC dissemination. Moreover, cancer cell phenotypic plasticity driven by EMT contributes to intratumoral heterogeneity and drug tolerance and is mechanistically associated with the emergence of cells exhibiting cancer stem cells (CSCs) phenotype. In this review we summarize the available data on the signaling cascades regulating EMT and the molecular isnteractions between pancreatic cancer and stromal cells that activate them. In addition, we provide a link between EMT, tumor progression, and chemoresistance in PDAC.

KDM6A Regulates Cell Plasticity and Pancreatic Cancer Progression by Noncanonical Activin Pathway

BACKGROUND & AIMS

Inactivating mutations of KDM6A, a histone demethylase, were frequently found in pancreatic ductal adenocarcinoma (PDAC). We investigated the role of KDM6A (lysine demethylase 6A) in PDAC development.

METHODS

We performed a pancreatic tissue microarray analysis of KDM6A protein levels. We used human PDAC cell lines for KDM6A knockout and knockdown experiments. We performed bromouridine sequencing analysis to elucidate the effects of KDM6A loss on global transcription. We performed studies with Ptf1a^Cre; LSL-Kras^G12D; Trp53^R172H/+; Kdm6a^{fl/fl or fl/Y}, Ptf1a^Cre; Kdm6a^{fl/fl or fl/Y}, and orthotopic xenograft mice to investigate the impacts of Kdm6a deficiency on pancreatic tumorigenesis and pancreatitis.

RESULTS

Loss of KDM6A was associated with metastasis in PDAC patients. Bromouridine sequencing analysis showed up-regulation of the epithelial-mesenchymal transition pathway in PDAC cells deficient in KDM6A. Loss of KDM6A promoted mesenchymal morphology, migration, and invasion in PDAC cells in vitro. Mechanistically, activin A and subsequent p38 activation likely mediated the role of KDM6A loss. Inhibiting either activin A or p38 reversed the effect. Pancreas-specific Kdm6a-knockout mice pancreata showed accelerated PDAC progression, developed a more aggressive undifferentiated type of PDAC, and increased metastases in the background of Kras and p53 mutations. Kdm6a-deficient pancreata in a pancreatitis model had a delayed recovery with increased PDAC precursor lesions compared with wild-type pancreata.

CONCLUSIONS

Loss of KDM6A accelerates PDAC progression and metastasis, most likely by a noncanonical p38-dependent activin A pathway. KDM6A also promotes pancreatic tissue recovery from pancreatitis. Activin A might be used as a therapeutic target for KDM6A-deficient PDACs.

Interleukins in cancer: from biology to therapy

Interleukins and associated cytokines serve as the means of communication for innate and adaptive immune cells as well as non-immune cells and tissues. Thus, interleukins have a critical role in cancer development, progression and control. Interleukins can nurture an environment enabling and favouring cancer growth while simultaneously being essential for a productive tumour-directed immune response. These properties of interleukins can be exploited to improve immunotherapies to promote effectiveness as well as to limit side effects. This Review aims to unravel some of these complex interactions.

STAT3 phosphorylation is required for the HepaCAM-mediated inhibition of castration-resistant prostate cancer cell viability and metastasis

BACKGROUND

Castration-resistant prostate cancer (CRPC) is an advanced disease that is difficult to treat, the mechanism of it is unclear. This study illustrated the function of hepatocyte cell adhesion molecule (HepaCAM) on CRPC cell viability and metastasis.

METHODS

The expression of HepaCAM and p-STAT3 in CRPC tissues were determined by immunohistochemistry and western blot analysis. Cell Counting Kit-8 and colony formation assays were deployed to analyze the growth ability of CRPC cells following the adenovirus-mediated re-expression of HepaCAM. CRPC cell migration and invasion capacity were investigated by wound healing and Matrigel-coated transwell assays, respectively. The messenger RNA or protein levels of p-STAT3, CyclinD1, cMyc, MMP2, MMP9, and VEGF were determined by reverse transcription (RT) followed by quantitative real-time polymerase chain reaction (RT-qPCR), and western blot analysis after either HepaCAM re-expression alone or in combination with IL-22 treatment. A CRPC orthotopic xenograft mouse model was applied to investigate the functional effect of HepaCAM on the metastasis of CRPC cells to the lungs.

RESULTS

The expression levels of HepaCAM were decreased while those of p-STAT3 were elevated in CRPC cells compare with surrounding benign tissues (p < .001). The overexpression of HepaCAM in CRPC cells notably reduced proliferation, migration, and invasion by inhibiting the expression of p-STAT3, CyclinD1, cMyc, MMP2, MMP9, and VEGF (p < .05). In addition, the expression of HepaCAM significantly inhibited the IL-22/p-STAT3 axis and the metastasis of CRPC cells to the lungs.

CONCLUSIONS

Our data suggested that HepaCAM suppressed the viability of CRPC cells via the IL-22/p-STAT3 axis and inhibited the metastasis of CRPC cells from the prostate to the lungs (p < .05).

Inflammation-Induced Tumorigenesis and Metastasis

Inflammation, especially chronic inflammation, plays a pivotal role in tumorigenesis and metastasis through various mechanisms and is now recognized as a hallmark of cancer and an attractive therapeutic target in cancer. In this review, we discuss recent advances in molecular mechanisms of how inflammation promotes tumorigenesis and metastasis and suppresses anti-tumor immunity in various types of solid tumors, including esophageal, gastric, colorectal, liver, and pancreatic cancer as well as hematopoietic malignancies.

Epithelial-mesenchymal transition: When tumor cells meet myeloid-derived suppressor cells

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous myeloid cell population characterized by protumoral functions in the tumor immune network. An increasing number of studies have focused on the biological functions of MDSCs in tumor immunity. Epithelial-mesenchymal transition (EMT) is a cellular plasticity process accompanied by a loss of epithelial phenotypes and an acquisition of mesenchymal phenotypes. In general, tumor cells that undergo EMT are more likely to invade and metastasize. Recently, extensive evidence suggests that EMT is closely related to a highly immunosuppressive environment. This review will summarize the immunosuppressive capacities of MDSC subsets and their distinct role in tumor EMT and further discuss immunotherapy for tumor EMT by targeting MDSCs.

C3a and C5a facilitates the metastasis of myeloma cells by activating Nrf2

Multiple myeloma (MM) is still an incurable hematological malignancy, with even poorer prognosis in MM patients with distant invasion. The present study was designed to explore the effects of C3a and C5a on the migration, invasion, and adhesion of MM tumor cells and to investigate the underlying mechanisms. As a result, the levels of C3a and C5a in plasma of MM patients were significantly higher than those of healthy donors. Consistently, the expression of C3a and C5a receptors on myeloma cells of MM patients was also significantly higher than that on sorted plasma cells of normal donors. C3a and C5a have been confirmed to increase the migration, invasion and adhesion of MM cell lines by activating the MEK/ERK pathway and increasing the nuclear transfer of Nrf2 in vitro. Moreover, the MM cell line U266 with Nrf2 downregulation was incubated with C3a and C5a, followed by injection into the tail vein of NOD-SCID mice. We found that Nrf2 downregulation attenuated the migration of anaphylatoxin C3a and C5a to MM tumor cells in bone marrow, liver and lung in vivo. In conclusion, our results indicate that activation of the complement cascade in MM patients may contribute to the migration, invasion and adhesion of MM cells, and this type of tumor cells dissemination in MM is, at least partially, regulated by Nrf2. Thereby, complement suppression or Nrf2 downregulation might offer a novel therapeutic opportunity for MM.

Immunotherapy for pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains a lethal cancer with an urgent need for better medical therapies. Efforts have been made to investigate the efficacy of immunotherapy, particularly given the hallmarks of immune suppression and exhaustion in PDAC tumors. Here, we review the molecular components responsible for the immune-privileged state in PDAC and provide an overview of the immunotherapeutic strategies for PDAC including vaccine therapy, checkpoint blockade, myeloid-targeted therapy, and immune agonist therapy.

Multimodal Mapping of the Tumor and Peripheral Blood Immune Landscape in Human Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDA) is characterized by an immune-suppressive tumor microenvironment that renders it largely refractory to immunotherapy. We implemented a multimodal analysis approach to elucidate the immune landscape in PDA. Using a combination of CyTOF, single-cell RNA sequencing, and multiplex immunohistochemistry on patient tumors, matched blood, and non-malignant samples, we uncovered a complex network of immune-suppressive cellular interactions. These experiments revealed heterogeneous expression of immune checkpoint receptors in individual patient's T cells and increased markers of CD8+ T cell dysfunction in advanced disease stage. Tumor-infiltrating CD8+ T cells had an increased proportion of cells expressing an exhausted expression profile that included upregulation of the immune checkpoint TIGIT, a finding that we validated at the protein level. Our findings point to a profound alteration of the immune landscape of tumors, and to patient-specific immune changes that should be taken into account as combination immunotherapy becomes available for pancreatic cancer.

Neutrophil to lymphocyte ratio predicts prognosis in unresectable pancreatic cancer

Inflammation-based prognostic indicators have been developed to predict the prognosis in patients with pancreatic cancer. However, prognostic indices have not been established in patients with unresectable pancreatic cancer, including those without indication for chemotherapy at diagnosis. This study aimed to identify the predictors in all patients with unresectable pancreatic cancer. We retrospectively analyzed data of 119 patients with unresectable pancreatic cancer from June 2006 to September 2018. The following laboratory parameters were evaluated: the Glasgow Prognostic Score (GPS), modified GPS, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), C-reactive protein albumin (CRP/Alb) ratio, and prognostic nutritional index (PNI). We performed time-dependent receiver operating characteristic analysis, overall survival (OS) analysis, and univariate and multivariate analyses to determine the prognostic factors in patients with unresectable pancreatic cancer. The cut-off value for NLR was determined to be 3.74. The 6-month OS rates in low and high NLR groups were 75.5% and 18.8% (P < 0.001). In the univariate analysis, advanced age (P = 0.003), metastatic pancreatic cancer (P = 0.037), no treatment (P < 0.001), worse Eastern Cooperative Oncology Group Performance Status (ECOG-PS) (P < 0.001), high GPS (P < 0.001), high modified GPS (P < 0.001), high NLR (P < 0.001), high PLR (P = 0.002), high CRP/Alb ratio (P < 0.001), and low PNI (P < 0.001) were identified as the prognostic factors. The multivariate analysis revealed that metastatic pancreatic cancer (P = 0.046), no treatment (P < 0.001), worse ECOG-PS (P = 0.002), and high NLR (P < 0.001) were independently associated with OS. We revealed that the high NLR could be an independent indicator of poor prognosis in patients with unresectable pancreatic cancer.

Macrophages in pancreatic cancer: An immunometabolic perspective

As one of the most fatal gastrointestinal cancers, pancreatic cancer (PC) has a long-term survival rate that has shown limited improvement during recent decades and remains dismal. The poor prognosis is attributed to challenges in early detection, low opportunity for radical resection and resistance to chemotherapy and radiation. Macrophages are one of the most abundant infiltrating immune cells in PC stroma, and they can crosstalk with cancer cells, adipocytes and other stromal cells to modulate metabolism, inflammation and immune status, create an immunosuppressive tumor microenvironment (TME), and ultimately facilitate tumor initiation and progression. In this review, we summarize recent advances in our understanding of macrophage origin, distribution and polarization, as well as provide a thorough review of the role macrophages in PC carcinogenesis and development, as well as the underlying molecular mechanism. Additionally, we investigated macrophage targets in preclinical and clinical trials to evaluate their potential therapeutic value in PC.