RAGE signaling sustains inflammation and promotes tumor development

RAGE is a key regulator of ductular reaction-mediated fibrosis during cholestasis

Ductular reaction (DR) is the hallmark of cholestatic diseases manifested in the proliferation of bile ductules lined by biliary epithelial cells (BECs). It is commonly associated with an increased risk of fibrosis and liver failure. The receptor for advanced glycation end products (RAGE) was identified as a critical mediator of DR during chronic injury. Yet, the direct link between RAGE-mediated DR and fibrosis as well as the mode of interaction between BECs and hepatic stellate cells (HSCs) to drive fibrosis remain elusive. Here, we delineate the specific function of RAGE on BECs during DR and its potential association with fibrosis in the context of cholestasis. Employing a biliary lineage tracing cholestatic liver injury mouse model, combined with whole transcriptome sequencing and in vitro analyses, we reveal a role for BEC-specific Rage activity in fostering a pro-fibrotic milieu. RAGE is predominantly expressed in BECs and contributes to DR. Notch ligand Jagged1 is secreted from activated BECs in a Rage-dependent manner and signals HSCs in trans, eventually enhancing fibrosis during cholestasis.

Evaluation of S100A8/A9 and neutrophils as prognostic markers in metastatic melanoma patients under immune-checkpoint inhibition

Immune-checkpoint inhibitors (ICIs) have revolutionized melanoma treatment, yet approximately half of patients do not respond to these therapies. Identifying prognostic biomarkers is crucial for treatment decisions. Our retrospective study assessed liquid biopsies and tumor tissue analyses for two potential biomarkers: danger-associated molecular pattern (DAMP) S100A8/A9 and its source, neutrophils. In 43 metastatic unresected stage III/IV melanoma patients, elevated serum levels of S100A8/A9 and neutrophils before and during ICI treatment correlated with worse outcomes. Furthermore, in 113 melanoma patients, neutrophil expression in the tumor microenvironment (TME) was associated with relapse and reduced survival. Measuring S100A8/A9 and neutrophils could enhance immunotherapy monitoring by predicting impaired clinical outcomes and non-response to ICIs. Serum S100A8/A9 levels and neutrophil counts at baseline (T0) and during treatment (T3) correlated with reduced progression-free survival (PFS). Elevated S100A8/A9 levels at T0 and T3 negatively impacted overall survival (OS). Notably, neutrophil infiltration was more prevalent in primary melanomas than in nevi and metastases, and its presence in primary melanomas was linked to poorer survival. S100A8/A9 serum levels, neutrophil counts, and tumor-associated neutrophil infiltration represent promising biomarkers for predicting treatment response and clinical outcomes in melanoma patients receiving ICIs. SIGNIFICANCE: These findings underscore the critical need for reliable biomarkers in melanoma research, particularly for predicting responses to immune-checkpoint inhibitors (ICIs). Identifying S100A8/A9 levels and neutrophil infiltration as potential indicators of treatment outcomes offers valuable insights for personalized therapy decisions. By enhancing monitoring and prognosis assessment, these biomarkers contribute to refining treatment strategies, ultimately improving patient care and outcomes. This research bridges gaps in understanding melanoma response mechanisms and highlights avenues for further investigation into immune-related markers, fostering advancements in precision medicine for melanoma patients.

S100A9 Affects Milk Protein Content by Regulating Amino Acid Transporters and the PI3K-Akt, WNT, and mTOR Signaling Pathways

BACKGROUND

Calgranulin B (S100A9) was found to be strongly associated with milk protein percentage in dairy cattle in our previous genome-wide association study.

METHODS

SNPs in S100A9 were identified via pooled sequencing, and genotyping of 1054 cows was performed individually using MassArray with MALDI-TOFMS technology. Association analyses between the S100A9 SNPs and five milk production traits were conducted using SAS 9.2 software. Functional studies of S100A9 were conducted using quantitative PCR, Western blot, CCK-8, and immunofluorescence assays.

RESULTS

In the present study, we further verified that two SNPs in S100A9, g.17115387 C>A and g.17115176 C>A, were significantly associated with milk protein percentage. We found that S100A9 could affect the expressions of caseins CSN1S1, CSN2, and CSN3 in MAC-T cells by regulating the expressions of amino acid transporter genes. We investigated the effects of S100A9 on the PI3K-Akt, WNT, and mTOR pathways, which are well known to play important roles in mammary gland development and milk protein synthesis. Our results suggest that S100A9 regulates the expressions of the relevant genes in these pathways, and thus potentially influences the protein synthesis in the mammary gland.

CONCLUSIONS

This study demonstrates the important role of the S100A9 gene in the milk protein trait of dairy cattle and provides new insights into the molecular mechanism of milk protein content.

Cytokeratin 17 expression is commonly observed in keratinocytic skin tumours and controls tissue homeostasis impacting human papillomavirus protein expression

BACKGROUND

The structured expression of several keratins in the skin is associated with differentiation status of the epidermal layers, whereas other keratins are upregulated only during wound healing, in skin disorders and in cancers. One of these stress keratins, K17, is correlated with poor prognosis in various cancer types and its loss has been shown to decelerate tumour growth. K17 expression can also be detected in cutaneous squamous cell carcinomas, where ultraviolet irradiation and infection with cutaneous human papillomaviruses are important cofactors. It was previously reported that K17 is upregulated in papillomavirus (PV)-induced benign skin lesions in mice and induces an immunological status that is beneficial for tumour growth.

OBJECTIVES

In order to investigate whether K17 upregulation is induced by PVs, we analysed K17 levels in skin tumour specimens of different animal models and humans.

METHODS

Various immunofluorescence stainings were performed to identify K17 expression as well as levels of E-cadherin, vimentin and CD271. Tissues were further analysed by polymerase chain reaction (PCR), quantitative (q)PCR and enzyme-linked immunosorbent assay to control for PV activity. K17 knockdown cells were generated and effects on viral life cycle were investigated by infection assays, qPCR and Western blotting.

RESULTS

We showed that K17 is commonly expressed in skin tumours and that its presence is not directly linked to viral oncoprotein expression. Rather, K17 expression seems to be a marker of epithelial differentiation and its absence in tumour tissue is associated with an epithelial-to-mesenchymal transition. We further demonstrated that the absence of K17 in skin tumours increases markers of cancer stem-like cells and negatively affects viral protein synthesis.

CONCLUSIONS

Collectively, our data indicate that K17 expression is a common feature in skin tumorigenesis. While K17 is not primarily targeted by PV oncoproteins, our in vivo and in vitro data suggest that it is an important regulator of epithelial differentiation and thus may play a role in controlling viral protein synthesis.

In-Depth Analysis of Olea europaea L. Leaf Extract: Alleviating Pulmonary Histological Disturbances, Pro-Inflammatory Responses, and Oxidative Stress from Isolated or Combined Exposure to Inhaled Toluene and Noise in Rats

The primary objective of this study was to investigate the pulmonary damage resulting from isolated or combined exposure to inhaled toluene (300 ppm) and noise 85 dB (A), with a focus on evaluating the potential protective effects of Olea europaea L. leaf extract (OLE). Forty-eight male Wistar rats were divided into eight groups: control (C), OLE treatment (O), noise exposure (N), noise exposure with OLE treatment (N+OLE), toluene exposure (T), toluene exposure with OLE treatment (T + OLE), co-exposure to toluene and noise (NT), and co-exposure with OLE treatment (NT + OLE). OLE (40 mg/kg/day) was administered daily for six weeks via oral gavage. Exposure to toluene and noise resulted in significant disruption of the pulmonary tissue structure, accompanied by oxidative stress, as evidenced by increased lipid peroxidation, diminished catalase and superoxide dismutase activities, and elevated pro-inflammatory cytokines IL6, IL-β, and TNF-α. Notably, the administration of OLE effectively mitigated oxidative stress and inflammation and preserved pulmonary histology. In conclusion, exposure to toluene and its combination with noise significantly elevated oxidative stress, inflammatory responses, and histological disruptions in the lung tissue. In contrast, noise exposure alone is characterized by minimal effects, although it is still associated with an inflammatory response. Notably, Olea europaea L. leaf extract (OLE) exhibits a substantial protective role, effectively mitigating the adverse effects of combined exposure and highlighting its potential as a therapeutic agent for lung health.

Role of innate host defense proteins in oral cancerogenesis

It is nowadays well accepted that chronic inflammation plays a pivotal role in tumor initiation and progression. Under this aspect, the oral cavity is predestined to examine this connection because periodontitis is a highly prevalent chronic inflammatory disease and oral squamous cell carcinomas are the most common oral malignant lesions. In this review, we describe how particular molecules of the human innate host defense system may participate as molecular links between these two important chronic noncommunicable diseases (NCDs). Specific focus is directed toward antimicrobial polypeptides, such as the cathelicidin LL-37 and human defensins, as well as S100 proteins and alarmins. We report in which way these peptides and proteins are able to initiate and support oral tumorigenesis, showing direct mechanisms by binding to growth-stimulating cell surface receptors and/or indirect effects, for example, inducing tumor-promoting genes. Finally, bacterial challenges with impact on oral cancerogenesis are briefly addressed.

Therapeutic potentials and targeting strategies of quercetin on cancer cells: Challenges and future prospects

BACKGROUND

Every cell in the human body is vital because it maintains equilibrium and carries out a variety of tasks, including growth and development. These activities are carried out by a set of instructions carried by many different genes and organized into DNA. It is well recognized that some lifestyle decisions, like using tobacco, alcohol, UV, or multiple sexual partners, might increase one's risk of developing cancer. The advantages of natural products for any health issue are well known, and researchers are making attempts to separate flavonoid-containing substances from plants. Various parts of plants contain a phenolic compound called flavonoid. Quercetin, which belongs to the class of compounds known as flavones with chromone skeletal structure, has anti-cancer activity.

PURPOSE

The study was aimed at investigating the therapeutic action of the flavonoid quercetin on various cancer cells.

METHODS

The phrases quercetin, anti-cancer, nanoparticles, and cell line were used to search the data using online resources such as PubMed, and Google Scholar. Several critical previous studies have been included.

RESULTS

Quercetin inhibits various dysregulated signaling pathways that cause cancer cells to undergo apoptosis to exercise its anticancer effects. Numerous signaling pathways are impacted by quercetin, such as the Hedgehog system, Akt, NF-κB pathway, downregulated mutant p53, JAK/STAT, G1 phase arrest, Wnt/β-Catenin, and MAPK. There are downsides to quercetin, like hydrophobicity, first-pass effect, instability in the gastrointestinal tract, etc., because of which it is not well-established in the pharmaceutical industry. The solution to these drawbacks in the future is using bio-nanomaterials like chitosan, PLGA, liposomes, and silk fibroin as carriers, which can enhance the target specificity of quercetin. The first section of this review covers the specifics of flavonoids and quercetin; the second section covers the anti-cancer activity of quercetin; and the third section explains the drawbacks and conjugation of quercetin with nanoparticles for drug delivery by overcoming quercetin's drawback.

CONCLUSIONS

Overall, this review presented details about quercetin, which is a plant derivative with a promising molecular mechanism of action. They inhibit cancer by various mechanisms with little or no side effects. It is anticipated that plant-based materials will become increasingly relevant in the treatment of cancer.

Activation and modulation of the AGEs-RAGE axis: Implications for inflammatory pathologies and therapeutic interventions - A review

Chronic inflammation is a common foundation for the development of many non-communicable diseases, particularly diabetes, atherosclerosis, and tumors. The activation of the axis involving Advanced Glycation End products (AGEs) and their receptor RAGE is a key promotive factor in the chronic inflammation process, influencing the pathological progression of these diseases. The accumulation of AGEs in the body results from an increase in glycation reactions and oxidative stress, especially pronounced in individuals with diabetes. By binding to RAGE, AGEs activate signaling pathways such as NF-κB, promoting the release of inflammatory factors, exacerbating cell damage and inflammation, and further advancing the formation of atherosclerotic plaques and tumor development. This review will delve into the molecular mechanisms by which the AGEs-RAGE axis activates chronic inflammation in the aforementioned diseases, as well as strategies to inhibit the AGEs-RAGE axis, aiming to slow or halt the progression of chronic inflammation and related diseases. This includes the development of AGEs inhibitors, RAGE antagonists, and interventions targeting upstream and downstream signaling pathways. Additionally, the early detection of AGEs levels and RAGE expression as biomarkers provides new avenues for the prevention and treatment of diabetes, atherosclerosis, and tumors.

Investigating Snake-Venom-Induced Dermonecrosis and Inflammation Using an Ex Vivo Human Skin Model

Snakebite envenoming is a neglected tropical disease that causes >100,000 deaths and >400,000 cases of morbidity annually. Despite the use of mouse models, severe local envenoming, defined by morbidity-causing local tissue necrosis, remains poorly understood, and human-tissue responses are ill-defined. Here, for the first time, an ex vivo, non-perfused human skin model was used to investigate temporal histopathological and immunological changes following subcutaneous injections of venoms from medically important African vipers (Echis ocellatus and Bitis arietans) and cobras (Naja nigricollis and N. haje). Histological analysis of venom-injected ex vivo human skin biopsies revealed morphological changes in the epidermis (ballooning degeneration, erosion, and ulceration) comparable to clinical signs of local envenoming. Immunostaining of these biopsies confirmed cell apoptosis consistent with the onset of necrosis. RNA sequencing, multiplex bead arrays, and ELISAs demonstrated that venom-injected human skin biopsies exhibited higher rates of transcription and expression of chemokines (CXCL5, MIP1-ALPHA, RANTES, MCP-1, and MIG), cytokines (IL-1β, IL-1RA, G-CSF/CSF-3, and GM-CSF), and growth factors (VEGF-A, FGF, and HGF) in comparison to non-injected biopsies. To investigate the efficacy of antivenom, SAIMR Echis monovalent or SAIMR polyvalent antivenom was injected one hour following E. ocellatus or N. nigricollis venom treatment, respectively, and although antivenom did not prevent venom-induced dermal tissue damage, it did reduce all pro-inflammatory chemokines, cytokines, and growth factors to normal levels after 48 h. This ex vivo skin model could be useful for studies evaluating the progression of local envenoming and the efficacy of snakebite treatments.

Immune Cell Migration to Cancer

Immune cell migration is required for the development of an effective and robust immune response. This elegant process is regulated by both cellular and environmental factors, with variables such as immune cell state, anatomical location, and disease state that govern differences in migration patterns. In all cases, a major factor is the expression of cell surface receptors and their cognate ligands. Rapid adaptation to environmental conditions partly depends on intrinsic cellular immune factors that affect a cell's ability to adjust to new environment. In this review, we discuss both myeloid and lymphoid cells and outline key determinants that govern immune cell migration, including molecules required for immune cell adhesion, modes of migration, chemotaxis, and specific chemokine signaling. Furthermore, we summarize tumor-specific elements that contribute to immune cell trafficking to cancer, while also exploring microenvironment factors that can alter these cellular dynamics within the tumor in both a pro and antitumor fashion. Specifically, we highlight the importance of the secretome in these later aspects. This review considers a myriad of factors that impact immune cell trajectory in cancer. We aim to highlight the immunotherapeutic targets that can be harnessed to achieve controlled immune trafficking to and within tumors.

Progress of research on the relationship between efferocytosis and tumor

Tumors are genetic changes that develop in an organism as a result of many internal and external causes. They affect the biological behavior of cells, cause them to grow independently, and give rise to new, perpetually proliferating organisms. Recent research has supported the critical function of tumor-associated macrophages in the development, progression, and metastasis of tumors through efferocytosis. Yet, there is still much to learn about the mechanisms behind their contribution to tumor pathological processes. As a result, it's critical to actively investigate how cytosolic processes contribute to the growth of tumors and to create novel therapeutic approaches.

RAGE engagement by SARS-CoV-2 enables monocyte infection and underlies COVID-19 severity

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has fueled the COVID-19 pandemic with its enduring medical and socioeconomic challenges because of subsequent waves and long-term consequences of great concern. Here, we chart the molecular basis of COVID-19 pathogenesis by analyzing patients' immune responses at single-cell resolution across disease course and severity. This approach confirms cell subpopulation-specific dysregulation in COVID-19 across disease course and severity and identifies a severity-associated activation of the receptor for advanced glycation endproducts (RAGE) pathway in monocytes. In vitro THP1-based experiments indicate that monocytes bind the SARS-CoV-2 S1-receptor binding domain (RBD) via RAGE, pointing to RAGE-Spike interaction enabling monocyte infection. Thus, our results demonstrate that RAGE is a functional receptor of SARS-CoV-2 contributing to COVID-19 severity.

RAGE/SNAIL1 signaling drives epithelial-mesenchymal plasticity in metastatic triple-negative breast cancer

Epithelial/Mesenchymal (E/M) plasticity plays a fundamental role both in embryogenesis and during tumorigenesis. The receptor for advanced glycation end products (RAGE) is a driver of cell plasticity in fibrotic diseases; however, its role and molecular mechanism in triple-negative breast cancer (TNBC) remains unclear. Here, we demonstrate that RAGE signaling maintains the mesenchymal phenotype of aggressive TNBC cells by enforcing the expression of SNAIL1. Besides, we uncover a crosstalk mechanism between the TGF-β and RAGE pathways that is required for the acquisition of mesenchymal traits in TNBC cells. Consistently, RAGE inhibition elicits epithelial features that block migration and invasion capacities. Next, since RAGE is a sensor of the tumor microenvironment, we modeled acute acidosis in TNBC cells and showed it promotes enhanced production of RAGE ligands and the activation of RAGE-dependent invasive properties. Furthermore, acute acidosis increases SNAIL1 levels and tumor cell invasion in a RAGE-dependent manner. Finally, we demonstrate that in vivo inhibition of RAGE reduces metastasis incidence and expands survival, consistent with molecular effects that support the relevance of RAGE signaling in E/M plasticity. These results uncover new molecular insights on the regulation of E/M phenotypes in cancer metastasis and provide rationale for pharmacological intervention of this signaling axis.

Contributing Role of High Mobility Group Box 1 Signaling in Oral Cancer Development and Therapy

Oral squamous cell carcinoma (OSCC) is the most frequent type of oral cancer of multifactorial origin, characterized by histological and clinical manifestations. To date, there are no specific biomarkers or treatment modalities available to efficiently manage this neoplasia, demanding further research on the molecular background of OSCC pathology. Elucidation of signal transduction pathways and associated molecules with differential expression and function in OSCC are expected to enhance the future development of molecular targeted therapies. Among signaling proteins with a potential functional role in OSCC, the High Mobility Group Box 1 (HMGB1) protein has stimulated scientific interest due to frequent upregulation, and implication in the progression of many types of head and neck cancer types. HMGB1 is a nuclear nonhistone protein and an extracellularly secreted cytokine that can interact with several signaling molecules implicated in the pathogenic pathways of OSCC. Binding of HMGB1 to specific receptors on OSCC cells such as the receptor of AGE (RAGE) and the toll-like receptor (TLR) has been shown to initiate several intercellular signaling cascades that can promote OSCC growth, invasion, and metastasis, indicating a potential target for patient prognosis and therapeutic approaches. The purpose of this review is to explore the functional role and associated signaling of HMGB1 in OSCC in order to reveal potential therapeutic targeting options.

RAGE ablation attenuates glioma progression and enhances tumor immune responses by suppressing galectin-3 expression

BACKGROUND

Malignant gliomas consist of heterogeneous cellular components that have adopted multiple overlapping escape mechanisms that overcome both targeted and immune-based therapies. The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily that is activated by diverse proinflammatory ligands present in the tumor microenvironment. Activation of RAGE by its ligands stimulates multiple signaling pathways that are important in tumor growth and invasion. However, treatment strategies that only target the interaction of RAGE with its ligands are ineffective as cancer therapies due to the abundance and diversity of exogenous RAGE ligands in gliomas.

METHODS

As an alternative approach to RAGE ligand inhibition, we evaluated the genetic ablation of RAGE on the tumorigenicity of 2 syngeneic murine glioma models. RAGE expression was inhibited in the GL261 and K-Luc gliomas by shRNA and CRSPR/Cas9 techniques prior to intracranial implantation. Tumor growth, invasion, and inflammatory responses were examined by histology, survival, Nanostring, and flow cytometry.

RESULTS

Intracellular RAGE ablation abrogated glioma growth and invasion by suppressing AKT and ERK1/2 activities and by downregulating MMP9 expression. Interestingly, RAGE inhibition in both glioma models enhanced tumor inflammatory responses by downregulating the expression of galectin-3 and potentiated immunotherapy responses to immune checkpoint blockade.

CONCLUSIONS

We demonstrated that intracellular RAGE ablation suppresses multiple cellular pathways that are important in glioma progression, invasion, and immune escape. These findings strongly support the development of RAGE ablation as a treatment strategy for malignant gliomas.

Social Isolation Activates Dormant Mammary Tumors, and Modifies Inflammatory and Mitochondrial Metabolic Pathways in the Rat Mammary Gland

Although multifactorial in origin, one of the most impactful consequences of social isolation is an increase in breast cancer mortality. How this happens is unknown, but many studies have shown that social isolation increases circulating inflammatory cytokines and impairs mitochondrial metabolism. Using a preclinical Sprague Dawley rat model of estrogen receptor-positive breast cancer, we investigated whether social isolation impairs the response to tamoxifen therapy and increases the risk of tumors emerging from dormancy, and thus their recurrence. We also studied which signaling pathways in the mammary glands may be affected by social isolation in tamoxifen treated rats, and whether an anti-inflammatory herbal mixture blocks the effects of social isolation. Social isolation increased the risk of dormant mammary tumor recurrence after tamoxifen therapy. The elevated recurrence risk was associated with changes in multiple signaling pathways including an upregulation of IL6/JAK/STAT3 signaling in the mammary glands and tumors and suppression of the mitochondrial oxidative phosphorylation (OXPHOS) pathway. In addition, social isolation increased the expression of receptor for advanced glycation end-products (RAGE), consistent with impaired insulin sensitivity and weight gain linked to social isolation. In socially isolated animals, the herbal product inhibited IL6/JAK/STAT3 signaling, upregulated OXPHOS signaling, suppressed the expression of RAGE ligands S100a8 and S100a9, and prevented the increase in recurrence of dormant mammary tumors. Increased breast cancer mortality among socially isolated survivors may be most effectively prevented by focusing on the period following the completion of hormone therapy using interventions that simultaneously target several different pathways including inflammatory and mitochondrial metabolism pathways.

Dialog beyond the Grave: Necrosis in the Tumor Microenvironment and Its Contribution to Tumor Growth

Damage-associated molecular patterns (DAMPs) are endogenous molecules released from the necrotic cells dying after exposure to various stressors. After binding to their receptors, they can stimulate various signaling pathways in target cells. DAMPs are especially abundant in the microenvironment of malignant tumors and are suspected to influence the behavior of malignant and stromal cells in multiple ways often resulting in promotion of cell proliferation, migration, invasion, and metastasis, as well as increased immune evasion. This review will start with a reminder of the main features of cell necrosis, which will be compared to other forms of cell death. Then we will summarize the various methods used to assess tumor necrosis in clinical practice including medical imaging, histopathological examination, and/or biological assays. We will also consider the importance of necrosis as a prognostic factor. Then the focus will be on the DAMPs and their role in the tumor microenvironment (TME). We will address not only their interactions with the malignant cells, frequently leading to cancer progression, but also with the immune cells and their contribution to immunosuppression. Finally, we will emphasize the role of DAMPs released by necrotic cells in the activation of Toll-like receptors (TLRs) and the possible contributions of TLRs to tumor development. This last point is very important for the future of cancer therapeutics since there are attempts to use TLR artificial ligands for cancer therapeutics.

Apoptosis-induced nuclear expulsion in tumor cells drives S100a4-mediated metastatic outgrowth through the RAGE pathway

Most tumor cells undergo apoptosis in circulation and at the metastatic organ sites due to host immune surveillance and a hostile microenvironment. It remains to be elucidated whether dying tumor cells have a direct effect on live tumor cells during the metastatic process and what the underlying mechanisms are. Here we report that apoptotic cancer cells enhance the metastatic outgrowth of surviving cells through Padi4-mediated nuclear expulsion. Tumor cell nuclear expulsion results in an extracellular DNA-protein complex that is enriched with receptor for advanced glycation endproducts (RAGE) ligands. The chromatin-bound RAGE ligand S100a4 activates RAGE receptors in neighboring surviving tumor cells, leading to Erk activation. In addition, we identified nuclear expulsion products in human patients with breast, bladder and lung cancer and a nuclear expulsion signature correlated with poor prognosis. Collectively, our study demonstrates how apoptotic cell death can enhance the metastatic outgrowth of neighboring live tumor cells.

Occurrence of Human Defensins and S100 Proteins in Head and Neck Basal Cell Carcinoma (BCC) Entities: hBD3 and S100A4 as Potential Biomarkers to Evaluate Successful Surgical Therapy

Background: The goal of this study is the identification of potential marker molecules for characterizing different basal cell carcinoma entities, to help improve clinical decisions for surgical resection therapy. Methods: Three different entities, sclerodermiform, solid and superficial basal cell carcinomas, were subjected to immunohistochemical microscopy and histomorphometric analyses for human α- (DEFA1/3; DEFA4) and β-defensins (hBD1/2/3) and special S100 proteins (S100A4/7/8/9). Thirty specimens of the three entities were evaluated. Analyses were performed by comparing tissue and cellular localization and staining intensities of tumorous with non-tumorous areas. Staining intensities were semiquantitatively examined by using an RGB-based model. Results: Human defensins are present in all three entities of basal cell carcinomas. They all show cytoplasmic immunostaining in cells of the epithelium, stroma and tumor. Notably, human β-defensin3 is accumulated in the cell nuclei of sclerodermiform and superficial basal cell carcinomas. S100A4 and A7 are undetectable in tumor regions. However, S100A4 occurs in cancer-associated stroma cells with nuclear staining in superficial basal cell carcinomas. Conclusion: Two candidates, namely hBD3 and S100A4, might be used as potential clinical tools for evaluating successful surgical resection therapy to avoid aesthetic and functional facial deformation.

Contributions of the receptor for advanced glycation end products axis activation in gastric cancer

Compelling shreds of evidence derived from both clinical and experimental research have demonstrated the crucial contribution of receptor for advanced glycation end products (RAGE) axis activation in the development of neoplasms, including gastric cancer (GC). This new actor in tumor biology plays an important role in the onset of a crucial and long-lasting inflammatory milieu, not only by supporting phenotypic changes favoring growth and dissemination of tumor cells, but also by functioning as a pattern-recognition receptor in the inflammatory response to Helicobacter pylori infection. In the present review, we aim to highlight how the overexpression and activation of the RAGE axis contributes to the proliferation and survival of GC cells as and their acquisition of more invasive phenotypes that promote dissemination and metastasis. Finally, the contribution of some single nucleotide polymorphisms in the RAGE gene as susceptibility or poor prognosis factors is also discussed.

The Receptor for Advanced Glycation Endproducts (RAGE) and Its Ligands S100A8/A9 and High Mobility Group Box Protein 1 (HMGB1) Are Key Regulators of Myeloid-Derived Suppressor Cells

Immunotherapies including checkpoint blockade immunotherapy (CBI) and chimeric antigen receptor T cells (CAR-T) have revolutionized cancer treatment for patients with certain cancers. However, these treatments are not effective for all cancers, and even for those cancers that do respond, not all patients benefit. Most cancer patients have elevated levels of myeloid-derived suppressor cells (MDSCs) that are potent inhibitors of antitumor immunity, and clinical and animal studies have demonstrated that neutralization of MDSCs may restore immune reactivity and enhance CBI and CAR-T immunotherapies. MDSCs are homeostatically regulated in that elimination of mature circulating and intratumoral MDSCs results in increased production of MDSCs from bone marrow progenitor cells. Therefore, targeting MDSC development may provide therapeutic benefit. The pro-inflammatory molecules S100A8/A9 and high mobility group box protein 1 (HMGB1) and their receptor RAGE are strongly associated with the initiation and progression of most cancers. This article summarizes the literature demonstrating that these molecules are integrally involved in the early development, accumulation, and suppressive activity of MDSCs, and postulates that S100A8/A9 and HMGB1 serve as early biomarkers of disease and in conjunction with RAGE are potential targets for reducing MDSC levels and enhancing CBI and CAR-T immunotherapies.

Photon- and Proton-Mediated Biological Effects: What Has Been Learned?

The current understanding of the effects of radiation is gradually becoming broader. However, it still remains unclear why some patients respond to radiation with a pronounced positive response, while in some cases the disease progresses. This is the motivation for studying the effects of radiation therapy not only on tumor cells, but also on the tumor microenvironment, as well as studying the systemic effects of radiation. In this framework, we review the biological effects of two types of radiotherapy: photon and proton irradiations. Photon therapy is a commonly used type of radiation therapy due to its wide availability and long-term history, with understandable and predictable outcomes. Proton therapy is an emerging technology, already regarded as the method of choice for many cancers in adults and children, both dosimetrically and biologically. This review, written after the analysis of more than 100 relevant literary sources, describes the local effects of photon and proton therapy and shows the mechanisms of tumor cell damage, interaction with tumor microenvironment cells and effects on angiogenesis. After systematic analysis of the literature, we can conclude that proton therapy has potentially favorable toxicological profiles compared to photon irradiation, explained mainly by physical but also biological properties of protons. Despite the fact that radiobiological effects of protons and photons are generally similar, protons inflict reduced damage to healthy tissues surrounding the tumor and hence promote fewer adverse events, not only local, but also systemic.

Understanding the role of glycation in the pathology of various non-communicable diseases along with novel therapeutic strategies

Glycation refers to carbonyl group condensation of the reducing sugar with the free amino group of protein, which forms Amadori products and advanced glycation end products (AGEs). These AGEs alter protein structure and function by configuring a negative charge on the positively charged arginine and lysine residues. Glycation plays a vital role in the pathogenesis of metabolic diseases, brain disorders, aging, and gut microbiome dysregulation with the aid of 3 mechanisms: (i) formation of highly reactive metabolic pathway-derived intermediates, which directly affect protein function in cells, (ii) the interaction of AGEs with its associated receptors to create oxidative stress causing the activation of transcription factor NF-κB, and (iii) production of extracellular AGEs hinders interactions between cellular and matrix molecules affecting vascular and neural genesis. Therapeutic strategies are thus required to inhibit glycation at different steps, such as blocking amino and carbonyl groups, Amadori products, AGEs-RAGE interactions, chelating transition metals, scavenging free radicals, and breaking crosslinks formed by AGEs. The present review focused on explicitly elaborating the impact of glycation-influenced molecular mechanisms in developing and treating noncommunicable diseases.

Phytochemicals as Potential Inhibitors of Advanced Glycation End Products: Health Aspects and Patent Survey

BACKGROUND

The glycation of proteins and lipids synthesizes the advanced glycation end products (AGEs), i.e., substances that irreversibly damage macromolecules present in tissues and organs, which contribute to the impairment of biological functions. For instance, the accumulation of AGEs induces oxidative stress, the inflammatory responses, and consequently the on set/worsening of diseases, including obesity, asthma, cognitive impairment, and cancer. There is a current demand on natural and low-cost sources of anti-AGE agents. As a result, food phytochemicals presented promising results to inhibit glycation and consequently, the formation of AGEs.

OBJECTIVE

Here we describe how the AGEs are present in food via Maillard reaction and in organs via natural aging, as well as the effects of AGEs on the worsening of diseases. Also we described the methods used to detect AGEs in samples, and the current findings on the use of phytochemicals (phenolic compounds, phytosterols, carotenoids, terpenes and vitamins) as natural therapeuticals to inhibit health damages via inhibition of AGEs in vitro and in vivo.

METHODS

This manuscript reviewed publications available in the PubMed and Science Direct databases dated from the last 20 years on the uses of phytochemicals for the inhibition of AGEs. Recent patents on the use of anti-AGEs drugs were reviewed with the use of Google Advanced Patents database.

RESULTS AND DISCUSSION

There is no consensus about which concentration of AGEs in blood serum should not be hazardous to the health of individuals. Food phytochemicals derived from agroindustry wastes, including peanut skins, and the bagasses derived from citrus and grapes are promising anti-AGEs agents via scavenging of free radicals, metal ions, the suppression of metabolic pathways that induces inflammation, the activation of pathways that promote antioxidant defense, and the blocking of AGE connection with the receptor for advanced glycation endproducts (RAGE).

CONCLUSION

Phytochemicals derived from agroindustry are promising anti-AGEs, which can be included to replace synthetic drugs to inhibit AGE formation, and consequently to act as therapeutical strategy to prevent and treat diseases caused by AGEs, including diabetes, ovarian cancer, osteoporosis, and Alzheimer's disease.

Canine chronic enteropathy—Current state-of-the-art and emerging concepts

Over the last decade, chronic inflammatory enteropathies (CIE) in dogs have received great attention in the basic and clinical research arena. The 2010 ACVIM Consensus Statement, including guidelines for the diagnostic criteria for canine and feline CIE, was an important milestone to a more standardized approach to patients suspected of a CIE diagnosis. Great strides have been made since understanding the pathogenesis and classification of CIE in dogs, and novel diagnostic and treatment options have evolved. New concepts in the microbiome-host-interaction, metabolic pathways, crosstalk within the mucosal immune system, and extension to the gut-brain axis have emerged. Novel diagnostics have been developed, the clinical utility of which remains to be critically evaluated in the next coming years. New directions are also expected to lead to a larger spectrum of treatment options tailored to the individual patient. This review offers insights into emerging concepts and future directions proposed for further CIE research in dogs for the next decade to come.

Histidine-Rich Glycoprotein Suppresses the S100A8/A9-Mediated Organotropic Metastasis of Melanoma Cells

The dissection of the complex multistep process of metastasis exposes vulnerabilities that could be exploited to prevent metastasis. To search for possible factors that favor metastatic outgrowth, we have been focusing on secretory S100A8/A9. A heterodimer complex of the S100A8 and S100A9 proteins, S100A8/A9 functions as a strong chemoattractant, growth factor, and immune suppressor, both promoting the cancer milieu at the cancer-onset site and cultivating remote, premetastatic cancer sites. We previously reported that melanoma cells show lung-tropic metastasis owing to the abundant expression of S100A8/A9 in the lung. In the present study, we addressed the question of why melanoma cells are not metastasized into the brain at significant levels in mice despite the marked induction of S100A8/A9 in the brain. We discovered the presence of plasma histidine-rich glycoprotein (HRG), a brain-metastasis suppression factor against S100A8/A9. Using S100A8/A9 as an affinity ligand, we searched for and purified the binding plasma proteins of S100A8/A9 and identified HRG as the major protein on mass spectrometric analysis. HRG prevents the binding of S100A8/A9 to the B16-BL6 melanoma cell surface via the formation of the S100A8/A9 complex. HRG also inhibited the S100A8/A9-induced migration and invasion of A375 melanoma cells. When we knocked down HRG in mice bearing skin melanoma, metastasis to both the brain and lungs was significantly enhanced. The clinical examination of plasma S100A8/A9 and HRG levels showed that lung cancer patients with brain metastasis had higher S100A8/A9 and lower HRG levels than nonmetastatic patients. These results suggest that the plasma protein HRG strongly protects the brain and lungs from the threat of melanoma metastasis.

Innate lymphoid cells in early tumor development

Innate and adaptive immune cells monitor, recognize, and eliminate transformed cells. Innate lymphoid cells (ILCs) are innate counterparts of T cells that play a key role in many facets of the immune response and have a profound impact on disease states, including cancer. ILCs regulate immune responses by responding and integrating a wide range of signals within the local microenvironment. As primarily tissue-resident cells, ILCs are ideally suited to sense malignant transformation and initiate anti-tumor immunity. However, as ILCs have been associated with anti-tumor and pro-tumor activities in established tumors, they could potentially have dual functions during carcinogenesis by promoting or suppressing the malignant outgrowth of premalignant lesions. Here we discuss emerging evidence that shows that ILCs can impact early tumor development by regulating immune responses against transformed cells, as well as the environmental cues that potentially induce ILC activation in premalignant lesions.

Antimicrobial peptides: Defending the mucosal epithelial barrier

The recent epidemic caused by aerosolized SARS-CoV-2 virus illustrates the importance and vulnerability of the mucosal epithelial barrier against infection. Antimicrobial proteins and peptides (AMPs) are key to the epithelial barrier, providing immunity against microbes. In primitive life forms, AMPs protect the integument and the gut against pathogenic microbes. AMPs have also evolved in humans and other mammals to enhance newer, complex innate and adaptive immunity to favor the persistence of commensals over pathogenic microbes. The canonical AMPs are helictical peptides that form lethal pores in microbial membranes. In higher life forms, this type of AMP is exemplified by the defensin family of AMPs. In epithelial tissues, defensins, and calprotectin (complex of S100A8 and S100A9) have evolved to work cooperatively. The mechanisms of action differ. Unlike defensins, calprotectin sequesters essential trace metals from microbes, which inhibits growth. This review focuses on defensins and calprotectin as AMPs that appear to work cooperatively to fortify the epithelial barrier against infection. The antimicrobial spectrum is broad with overlap between the two AMPs. In mice, experimental models highlight the contribution of both AMPs to candidiasis as a fungal infection and periodontitis resulting from bacterial dysbiosis. These AMPs appear to contribute to innate immunity in humans, protecting the commensal microflora and restricting the emergence of pathobionts and pathogens. A striking example in human innate immunity is that elevated serum calprotectin protects against neonatal sepsis. Calprotectin is also remarkable because of functional differences when localized in epithelial and neutrophil cytoplasm or released into the extracellular environment. In the cytoplasm, calprotectin appears to protect against invasive pathogens. Extracellularly, calprotectin can engage pathogen-recognition receptors to activate innate immune and proinflammatory mechanisms. In inflamed epithelial and other tissue spaces, calprotectin, DNA, and histones are released from degranulated neutrophils to form insoluble antimicrobial barriers termed neutrophil extracellular traps. Hence, calprotectin and other AMPs use several strategies to provide microbial control and stimulate innate immunity.

The 'Danse Macabre'-Neutrophils the Interactive Partner Affecting Oral Cancer Outcomes

Over the past few decades, tremendous advances in the prevention, diagnosis, and treatment of cancer have taken place. However for head and neck cancers, including oral cancer, the overall survival rate is below 50% and they remain the seventh most common malignancy worldwide. These cancers are, commonly, aggressive, genetically complex, and difficult to treat and the delay, which often occurs between early recognition of symptoms and diagnosis, and the start of treatment of these cancers, is associated with poor prognosis. Cancer development and progression occurs in concert with alterations in the surrounding stroma, with the immune system being an essential element in this process. Despite neutrophils having major roles in the pathology of many diseases, they were thought to have little impact on cancer development and progression. Recent studies are now challenging this notion and placing neutrophils as central interactive players with other immune and tumor cells in affecting cancer pathology. This review focuses on how neutrophils and their sub-phenotypes, N1, N2, and myeloid-derived suppressor cells, both directly and indirectly affect the anti-tumor and pro-tumor immune responses. Emphasis is placed on what is currently known about the interaction of neutrophils with myeloid innate immune cells (such as dendritic cells and macrophages), innate lymphoid cells, natural killer cells, and fibroblasts to affect the tumor microenvironment and progression of oral cancer. A better understanding of this dialog will allow for improved therapeutics that concurrently target several components of the tumor microenvironment, increasing the possibility of constructive and positive outcomes for oral cancer patients. For this review, PubMed, Web of Science, and Google Scholar were searched for manuscripts using keywords and combinations thereof of "oral cancer, OSCC, neutrophils, TANs, MDSC, immune cells, head and neck cancer, and tumor microenvironment" with a focus on publications from 2018 to 2021.

Low social and family well-being is associated with greater RAGE ligand s100A8/A9 and interleukin-1 beta levels in metastatic breast cancer patients

Greater inflammatory signaling has been shown to promote breast cancer disease progression and poorer clinical outcomes. Lower social support and social well-being have been related to greater inflammatory signaling and poorer clinical outcomes in women with non-metastatic breast cancer, and this appears to be independent of depression. However, little is known about these associations in women with metastatic disease. s100A8/A9 and interleukin 1 beta (IL-1β) proteins are widely studied in breast cancer and are considered as biomarkers of cancer progression or as having a causal role in carcinogenesis and cancer progression and metastasis via inflammatory signaling. The aim of this study was to examine the associations between less social/family well-being (SWB) and S100A8/A9 and IL-1β levels in women diagnosed with metastatic breast cancer. Sixty women (Mean age 58.95 ​± ​1.49) with a diagnosis of metastatic breast cancer participated in the study. The Functional Assessment of Cancer Therapy (FACT) social and family well-being (SWB) subscale and the Hospital Anxiety Depression Scale (HADS) were administered to patients undergoing a first- or second-line endocrine or oral chemotherapy treatment and who were not experiencing brain metastasis or visceral crisis. Salivary s100A8/A9 and IL-1β levels were assessed at 5PM on two consecutive days and averaged. Multiple regression tested the independent contribution of SWB on s100 A8/A9 and IL-1b while controlling for depression. Lower levels of SWB were associated with greater S100A8/A9 (ß ​= ​-0.345, p ​= ​0.007) and IL-1β (ß ​= ​-0.286, p ​= ​0.027) levels and these associations remained significant after controlling for depression. This work provides new evidence for the role of decreased SWB and greater s100A8/A9 and IL-1b levels in patients diagnosed with metastatic breast cancer. Psychosocial interventions that promote social support and positive social interactions through interpersonal skills may help metastatic breast cancer patients to improve their SWB. This may have salutary effects on cancer-promoting processes, which could provide psychological and physical health benefits.

Differences in kinetics and dynamics of endogenous versus exogenous advanced glycation end products (AGEs) and their precursors

Advanced glycation end products (AGEs) and their precursors, referred to as glycation products, are a heterogenous group of compounds being associated with adverse health effects. They are formed endogenously and in exogenous sources including food. This review investigates the roles of endogenously versus exogenously formed glycation products in the potential induction of adverse health effects, focusing on differences in toxicokinetics and toxicodynamics, which appeared to differ depending on the molecular mass of the glycation product. Based on the available data, exogenous low molecular mass (LMM) glycation products seem to be bioavailable and to contribute to dicarbonyl stress and protein cross-linking resulting in formation of endogenous AGEs. Bioavailability of exogenous high molecular mass (HMM) glycation products appears limited, while these bind to the AGE receptor (RAGE), initiating adverse health effects. Together, this suggests that RAGE-binding in relevant tissues will more likely result from endogenously formed glycation products. Effects on gut microbiota induced by glycation products is proposed as a third mode of action. Overall, studies which better discriminate between LMM and HMM glycation products and between endogenous and exogenous formation are needed to further elucidate the contributions of these different types and sources of glycation products to the ultimate biological effects.

Involvement of Oxidative Stress in Protective Cardiac Functions of Calprotectin

Calprotectin (CLP) belonging to the S-100 protein family is a heterodimeric complex (S100A8/S100A9) formed by two binding proteins. Upon cell activation, CLP stored in neutrophils is released extracellularly in response to inflammatory stimuli and acts as damage-associated molecular patterns (DAMPs). S100A8 and S100A9 possess both anti-inflammatory and anti-bacterial properties. The complex is a ligand of the toll-like receptor 4 (TLR4) and receptor for advanced glycation end (RAGE). At sites of infection and inflammation, CLP is a target for oxidation due to its co-localization with neutrophil-derived oxidants. In the heart, oxidative stress (OS) responses and S100 proteins are closely related and intimately linked through pathophysiological processes. Our review summarizes the roles of S100A8, S100A9 and CLP in the inflammation in relationship with vascular OS, and we examine the importance of CLP for the mechanisms driving in the protection of myocardium. Recent evidence interpreting CLP as a critical modulator during the inflammatory response has identified this alarmin as an interesting drug target.

A Dual Anti-Inflammatory and Anti-Proliferative 3-Styrylchromone Derivative Synergistically Enhances the Anti-Cancer Effects of DNA-Damaging Agents on Colon Cancer Cells by Targeting HMGB1-RAGE-ERK1/2 Signaling

The current anti-cancer treatments are not enough to eradicate tumors, and therefore, new modalities and strategies are still needed. Most tumors generate an inflammatory tumor microenvironment (TME) and maintain the niche for their development. Because of the critical role of inflammation via high-mobility group box 1 (HMGB1)–receptor for advanced glycation end-products (RAGE) signaling pathway in the TME, a novel compound possessing both anti-cancer and anti-inflammatory activities by suppressing the HMGB1-RAGE axis provides an effective strategy for cancer treatment. A recent work of our group found that some anti-cancer 3-styrylchromones have weak anti-inflammatory activities via the suppression of this axis. In this direction, we searched such anti-cancer molecules possessing potent anti-inflammatory activities and discovered 7-methoxy-3-hydroxy-styrylchromone (C6) having dual suppressive activities. Mechanism-of-action studies revealed that C6 inhibited the increased phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) under the stimulation of HMGB1-RAGE signaling and thereby suppressed cytokine production in macrophage-like RAW264.7 cells. On the other hand, in colorectal cancer HCT116 cells, C6 inhibited the activation of ERK1/2, cyclin-dependent kinase 1, and AKT, down-regulated the protein level of XIAP, and up-regulated pro-apoptotic Bax and caspase-3/7 expression. These alterations are suggested to be involved in the C6-induced suppression of cell cycle/proliferation and initiation of apoptosis in the cancer cells. More importantly, in cancer cells, the treatment of C6 potentiates the anti-cancer effects of DNA-damaging agents. Thus, C6 may be a promising lead for the generation of a novel class of cancer therapeutics.

Food-Related Carbonyl Stress in Cardiometabolic and Cancer Risk Linked to Unhealthy Modern Diet

Carbonyl stress is a condition characterized by an increase in the steady-state levels of reactive carbonyl species (RCS) that leads to accumulation of their irreversible covalent adducts with biological molecules. RCS are generated by the oxidative cleavage and cellular metabolism of lipids and sugars. In addition to causing damage directly, the RCS adducts, advanced glycation end-products (AGEs) and advanced lipoxidation end-products (ALEs), cause additional harm by eliciting chronic inflammation through receptor-mediated mechanisms. Hyperglycemia- and dyslipidemia-induced carbonyl stress plays a role in diabetic cardiovascular complications and diabetes-related cancer risk. Moreover, the increased dietary exposure to AGEs/ALEs could mediate the impact of the modern, highly processed diet on cardiometabolic and cancer risk. Finally, the transient carbonyl stress resulting from supraphysiological postprandial spikes in blood glucose and lipid levels may play a role in acute proinflammatory and proatherogenic changes occurring after a calorie dense meal. These findings underline the potential importance of carbonyl stress as a mediator of the cardiometabolic and cancer risk linked to today’s unhealthy diet. In this review, current knowledge in this field is discussed along with future research courses to offer new insights and open new avenues for therapeutic interventions to prevent diet-associated cardiometabolic disorders and cancer.

[Unintended Observations Leading to Macrophage Growth and Neutrophil Factor Research]

My research area in the pharmaceutical industry is innate immunity, especially in phagocytic cells. First, I studied the heat-stable growth factor of peripheral macrophages in tumorous ascitic fluid and found that lipoproteins are an influencing factor. Later, my colleagues and I found that lipid-containing substances, namely, oxidized low-density lipoprotein, dead neutrophils, or purified lipids that could be scavenged by macrophages, induce their growth. From the series of this study, I concluded that phagocytic substances induce macrophage growth by autocrine stimulation of granulocyte-macrophage colony-stimulating factor (GM-CSF). During the study, we found that neutrophils have growth-inhibitory effects against a variety of cells. Then, I elucidated that the primary factor is a zinc-binding protein, calprotectin, an abundant protein complex in the neutrophil cytosol. I found that calprotectin induces apoptosis in many cell types, including tumor cells and normal fibroblasts, and that the zinc-binding capacity is essential for its activity. Microscopic observations revealed that neutrophil extract contains factor-inducing three-dimensional cell aggregation of human mammary carcinoma, MCF-7. I elucidated that cathepsin G is responsible for this activity and that its effect is dependent on the activation of insulin-like growth factor-1. I believe that this modest, albeit novel, observation was crucial to my thirty-nine-year-long career researching phagocytic cells.

Dual Nature of RAGE in Host Reaction and Nurturing the Mother-Infant Bond

Non-enzymatic glycation is an unavoidable reaction that occurs across biological taxa. The final products of this irreversible reaction are called advanced glycation end-products (AGEs). The endogenously formed AGEs are known to be bioactive and detrimental to human health. Additionally, exogenous food-derived AGEs are debated to contribute to the development of aging and various diseases. Receptor for AGEs (RAGE) is widely known to elicit biological reactions. The binding of RAGE to other ligands (e.g., high mobility group box 1, S100 proteins, lipopolysaccharides, and amyloid-β) can result in pathological processes via the activation of intracellular RAGE signaling pathways, including inflammation, diabetes, aging, cancer growth, and metastasis. RAGE is now recognized as a pattern-recognition receptor. All mammals have RAGE homologs; however, other vertebrates, such as birds, amphibians, fish, and reptiles, do not have RAGE at the genomic level. This evidence from an evolutionary perspective allows us to understand why mammals require RAGE. In this review, we provide an overview of the scientific knowledge about the role of RAGE in physiological and pathological processes. In particular, we focus on (1) RAGE biology, (2) the role of RAGE in physiological and pathophysiological processes, (3) RAGE isoforms, including full-length membrane-bound RAGE (mRAGE), and the soluble forms of RAGE (sRAGE), which comprise endogenous secretory RAGE (esRAGE) and an ectodomain-shed form of RAGE, and (4) oxytocin transporters in the brain and intestine, which are important for maternal bonding and social behaviors.

P-selectin targeted RAGE-shRNA lipoplexes alleviate atherosclerosis-associated inflammation

The receptor for advanced glycation end products (RAGE) plays a central role in the chronic inflammatory process associated with atherosclerosis development. We aimed to develop lipoplexes carrying RAGE-short hairpin (sh) RNA, targeted to the adhesion molecule P-selectin, selectively expressed on the surface of activated endothelium (Psel-lipo/shRAGE) to down-regulate RAGE expression as a therapeutic strategy for atherosclerosis. In vitro, Psel-lipo/shRAGE lipoplexes were efficiently taken up by activated endothelial cells (EC), decreased the expression of RAGE protein, and proved to be functional by reducing the monocyte adhesion to activated EC. In ApoE-deficient mice, the targeted lipoplexes accumulated specifically and efficiently transfected the aorta. The repeated administration of Psel-lipo/shRAGE lipoplexes, twice per week for one month: i) reduced the expression of RAGE protein in the aorta by decreasing the expression of NF-kB and TNF-α; ii) diminished the plasma levels of TNF-α, IL6, IL-1β, and MCP-1; iii) inhibited the atherosclerotic plaque development and iv) had no significant adverse effects. In conclusion, the newly developed Psel-lipo/shRAGE lipoplexes reduce the inflammatory processes associated with RAGE signaling and the progression of atherosclerosis in ApoE-deficient mice. Downregulation of RAGE employing these lipoplexes may represent a promising new targeted therapy to block atherosclerosis progression.

Calprotectin: from biomarker to biological function

The incidence of inflammatory bowel diseases (IBD) emerged with Westernisation of dietary habits worldwide. Crohn's disease and ulcerative colitis are chronic debilitating conditions that afflict individuals with substantial morbidity and challenge healthcare systems across the globe. Since identification and characterisation of calprotectin (CP) in the 1980s, faecal CP emerged as significantly validated, non-invasive biomarker that allows evaluation of gut inflammation. Faecal CP discriminates between inflammatory and non-inflammatory diseases of the gut and portraits the disease course of human IBD. Recent studies revealed insights into biological functions of the CP subunits S100A8 and S100A9 during orchestration of an inflammatory response at mucosal surfaces across organ systems. In this review, we summarise longitudinal evidence for the evolution of CP from biomarker to rheostat of mucosal inflammation and suggest an algorithm for the interpretation of faecal CP in daily clinical practice. We propose that mechanistic insights into the biological function of CP in the gut and beyond may facilitate interpretation of current assays and guide patient-tailored medical therapy in IBD, a concept warranting controlled clinical trials.

Leveling Up the Controversial Role of Neutrophils in Cancer: When the Complexity Becomes Entangled

Neutrophils are the most abundant immune cell in the circulation of human and act as gatekeepers to discard foreign elements that have entered the body. They are essential in initiating immune responses for eliminating invaders, such as microorganisms and alien particles, as well as to act as immune surveyors of cancer cells, especially during the initial stages of carcinogenesis and for eliminating single metastatic cells in the circulation and in the premetastatic organs. Since neutrophils can secrete a whole range of factors stored in their many granules as well as produce reactive oxygen and nitrogen species upon stimulation, neutrophils may directly or indirectly affect carcinogenesis in both the positive and negative directions. An intricate crosstalk between tumor cells, neutrophils, other immune cells and stromal cells in the microenvironment modulates neutrophil function resulting in both anti- and pro-tumor activities. Both the anti-tumor and pro-tumor activities require chemoattraction towards the tumor cells, neutrophil activation and ROS production. Divergence is seen in other neutrophil properties, including differential secretory repertoire and membrane receptor display. Many of the direct effects of neutrophils on tumor growth and metastases are dependent on tight neutrophil–tumor cell interactions. Among them, the neutrophil Mac-1 interaction with tumor ICAM-1 and the neutrophil L-selectin interaction with tumor-cell sialomucins were found to be involved in the neutrophil-mediated capturing of circulating tumor cells resulting in increased metastatic seeding. On the other hand, the anti-tumor function of neutrophils was found to rely on the interaction between tumor-surface-expressed receptor for advanced glycation end products (RAGE) and Cathepsin G expressed on the neutrophil surface. Intriguingly, these two molecules are also involved in the promotion of tumor growth and metastases. RAGE is upregulated during early inflammation-induced carcinogenesis and was found to be important for sustaining tumor growth and homing at metastatic sites. Cathepsin G was found to be essential for neutrophil-supported lung colonization of cancer cells. These data level up the complexity of the dual role of neutrophils in cancer.

S100 Proteins in Pancreatic Cancer: Current Knowledge and Future Perspectives

Pancreatic cancer (PC) is a highly malignant tumor occurring in the digestive system. Currently, there is a lack of specific and effective interventions for PC; thus, further exploration regarding the pathogenesis of this malignancy is warranted. The S100 protein family, a collection of calcium-binding proteins expressed only in vertebrates, comprises 25 members with high sequence and structural similarity. Dysregulated expression of S100 proteins is a biomarker of cancer progression and prognosis. Functionally, these proteins are associated with the regulation of multiple cellular processes, including proliferation, apoptosis, growth, differentiation, enzyme activation, migration/invasion, Ca2+ homeostasis, and energy metabolism. This review highlights the significance of the S100 family in the diagnosis and prognosis of PC and its vital functions in tumor cell metastasis, invasion and proliferation. A further understanding of S100 proteins will provide potential therapeutic targets for preventing or treating PC.

Intranasal delivery of self-assembled nanoparticles of therapeutic peptides and antagomirs elicits anti-tumor effects in an intracranial glioblastoma model

MicroRNA-21 (miR-21) is involved in the progression of glioblastoma through inhibition of pro-apoptotic genes. Antisense RNA against miR-21 (antagomir-21) has been developed as a potential therapeutic reagent for the treatment of glioblastoma. The receptor for advanced glycation end-products (RAGE) is also involved in the progression of glioblastoma through induction of angiogenic factors. Therefore, RAGE-antagonist peptide (RAP) is proposed to be an anti-tumor reagent. In this study, self-assembled nanoparticles were produced solely with therapeutic agents, antagomir-21 and RAP, with no additional carrier. The therapeutic effects of the nanoparticles by intranasal delivery were evaluated in intracranial glioblastoma animal models. First, physical characterizations such as size/zeta-potential study, scanning electron microscopy, and gel retardation assays showed that antagomir-21 and RAP formed stable nanoparticles without any additional reagents. The ratio between antagomir-21 and RAP was optimized by an in vitro cellular uptake study. The antagomir-21/RAP nanoparticles were administrated intranasally in the intracranial glioblastoma animal models to bypass the blood-brain-barrier. As a result, the nanoparticles reduced the miR-21 levels in tumors. Inhibition of miR-21 by the nanoparticles induced the expression of pro-apoptotic genes, such as PTEN and PDCD4, which enhanced tumor cell apoptosis. In addition, the expression of RAGE was suppressed by the nanoparticles, resulting in decreased levels of vascular endothelial growth factor in the tumor. The reduction of CD31-positive endothelial cells confirmed the anti-angiogenic effects of the nanoparticles. The results indicate that the intranasal delivery of the self-assembled nanoparticles of antagomir-21 and RAP is an efficient treatment of glioblastoma.

Macrophage Polarization States in the Tumor Microenvironment

The M1/M2 macrophage paradigm plays a key role in tumor progression. M1 macrophages are historically regarded as anti-tumor, while M2-polarized macrophages, commonly deemed tumor-associated macrophages (TAMs), are contributors to many pro-tumorigenic outcomes in cancer through angiogenic and lymphangiogenic regulation, immune suppression, hypoxia induction, tumor cell proliferation, and metastasis. The tumor microenvironment (TME) can influence macrophage recruitment and polarization, giving way to these pro-tumorigenic outcomes. Investigating TME-induced macrophage polarization is critical for further understanding of TAM-related pro-tumor outcomes and potential development of new therapeutic approaches. This review explores the current understanding of TME-induced macrophage polarization and the role of M2-polarized macrophages in promoting tumor progression.

Cross-talks in colon cancer between RAGE/AGEs axis and inflammation/immunotherapy

The tumour microenvironment is the result of the activity of many types of cells in various metabolic states, whose metabolites are shared between cells. This cellular complexity results in an availability profile of nutrients and reactive metabolites such as advanced glycation end products (AGE). The tumour microenvironment is not favourable to immune cells due to hypoxia and for the existence of significant competition between various types of cells for a limited nutrient pool. However, it is now known that cancer cells can influence the host's immune reaction through the expression and secretion of numerous molecules. The microenvironment can therefore present itself in different patterns that contribute to shaping immune surveillance. Colorectal cancer (CRC) is one of the most important causes of death in cancer patients. Recently, immunotherapy has begun to give encouraging results in some groups of patients suffering from this neoplasm. The analysis of literature data shows that the RAGE (Receptor for advanced glycation end products) and its numerous ligands contribute to connect the energy metabolic pathway, which appears prevalently disconnected by mitochondrial running, with the immune reaction, conditioned by local microbiota and influencing tumour growth. Understanding how metabolism in cancer and immune cells shapes response and resistance to therapy, will provide novel potential strategies to increase both the number of tumour types treated by immunotherapy and the rate of immunotherapy response. The analysis of literature data shows that an immunotherapy approach based on the knowledge of RAGE and its ligands is not only possible, but also desirable in the treatment of CRC.

The S100 Protein Family as Players and Therapeutic Targets in Pulmonary Diseases

The S100 protein family consists of over 20 members in humans that are involved in many intracellular and extracellular processes, including proliferation, differentiation, apoptosis, Ca₂⁺ homeostasis, energy metabolism, inflammation, tissue repair, and migration/invasion. Although there are structural similarities between each member, they are not functionally interchangeable. The S100 proteins function both as intracellular Ca²⁺ sensors and as extracellular factors. Dysregulated responses of multiple members of the S100 family are observed in several diseases, including the lungs (asthma, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, cystic fibrosis, pulmonary hypertension, and lung cancer). To this degree, extensive research was undertaken to identify their roles in pulmonary disease pathogenesis and the identification of inhibitors for several S100 family members that have progressed to clinical trials in patients for nonpulmonary conditions. This review outlines the potential role of each S100 protein in pulmonary diseases, details the possible mechanisms observed in diseases, and outlines potential therapeutic strategies for treatment.

Plasma concentrations of advanced glycation end-products and colorectal cancer risk in the EPIC study

Advanced glycation end-products (AGEs) are a heterogeneous group of compounds formed by the non-enzymatic reaction between amino acids and reducing sugars, or dicarbonyls as intermediate compounds. Experimental studies suggest that AGEs may promote colorectal cancer, but prospective epidemiologic studies are inconclusive. We conducted a case-control study nested within a large European cohort. Plasma concentrations of three protein-bound AGEs-Nε-(carboxy-methyl)lysine (CML), Nε-(carboxy-ethyl)lysine (CEL) and Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1)-were measured by ultra-performance liquid chromatography-tandem mass spectrometry in baseline samples collected from 1378 incident primary colorectal cancer cases and 1378 matched controls. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were computed using conditional logistic regression for colorectal cancer risk associated with CML, CEL, MG-H1, total AGEs, and [CEL+MG-H1: CML] and [CEL:MG-H1] ratios. Inverse colorectal cancer risk associations were observed for CML (OR comparing highest to lowest quintile, ORQ5 versus Q1 = 0.40, 95% CI: 0.27-0.59), MG-H1 (ORQ5 versus Q1 = 0.73, 95% CI: 0.53-1.00) and total AGEs (OR Q5 versus Q1 = 0.52, 95% CI: 0.37-0.73), whereas no association was observed for CEL. A higher [CEL+MG-H1: CML] ratio was associated with colorectal cancer risk (ORQ5 versus Q1 = 1.91, 95% CI: 1.31-2.79). The associations observed did not differ by sex, or by tumour anatomical sub-site. Although individual AGEs concentrations appear to be inversely associated with colorectal cancer risk, a higher ratio of methylglyoxal-derived AGEs versus those derived from glyoxal (calculated by [CEL+MG-H1: CML] ratio) showed a strong positive risk association. Further insight on the metabolism of AGEs and their dicarbonyls precursors, and their roles in colorectal cancer development is needed.

The receptor for advanced glycation endproducts (RAGE) decreases survival of tumor-bearing mice by enhancing the generation of lung metastasis-associated myeloid-derived suppressor cells

Metastatic cancer has a poor prognosis. Novel pharmacologic targets need to be identified. The receptor for advanced glycation endproducts (RAGE) is a pattern recognition receptor constitutively expressed in the lungs. Absence of overt disease in RAGE null mice suggests that RAGE is unnecessary or redundant in health. We report that RAGE null tumor-bearing mice have reduced lung metastasis and improved survival. Bone marrow chimera studies suggest that hematopoietic cell RAGE is an important contributor to these effects. Deletion of RAGE reduces both the quantity and suppressive activity of tumor-induced MDSC. Protein and mRNA studies suggest that RAGE contributes to the generation and function of MDSC including expression of the alarmins S100A8/A9 and activity of inducible nitric oxide synthase, arginase-1, and NF-κB. These findings demonstrate the important role of RAGE in determining the quantity and function of tumor-associated MDSC and suggest RAGE as a pharmacologic target for patients with metastatic disease.

Examination of the Effectiveness of the Healthy Empowered Active Lifestyles (HEAL) Program on Advanced Glycation End Products

This pilot study investigated the effectiveness of the healthy empowered active lifestyles (HEAL) program to reduce circulatory levels of advanced glycation end products (AGEs) and assess its relationship to BMI, % body fat, fasting glucose, and A1C. The HEAL program was delivered at a local wellness center using a team-based approach and focused on physical activity and dietary education. A sample of twenty primarily European American (19 white, 1 black) participants (i.e., 10 males, 10 females) aged 26 to 71 (m = 48.75 ± 10.26) completed 12 weeks of the HEAL intervention. Pre to post changes in AGEs, BMI, % body fat, fasting glucose, and A1C were examined as primary outcomes. The findings showed participants had the following average reductions: AGEs 36.04 ± 18.48 ug/mL, BMI 2.0 ± 1.2 kg/m2, % body fat 3.18 ± 1.57%, fasting glucose 5.9 ± 17.21 mg/dL, and A1C 0.68 ± 1.11%. All twenty participants successfully completed the entire twelve weeks of the HEAL intervention. The results of this study show that the HEAL intervention provides beneficial reductions of AGEs, BMI, % body fat, fasting glucose, and A1C. In addition, the high adherence shows promise, and demonstrates the potential for HEAL as a behavioral intervention to improve pre-diabetic and other inflammatory related comorbidities. Further replication of results via additional randomized controlled trials is needed.

Inhibition of the Receptor for Advanced Glycation End Products Enhances the Cytotoxic Effect of Gemcitabine in Murine Pancreatic Tumors

Pancreatic ductal adenocarcinoma (PDAC) remains a very difficult cancer to treat. Recent in vitro and in vivo studies suggest that the activation of the receptor for advanced glycation end products (RAGE) by its ligands stimulates pancreatic cancer cell proliferation and tumor growth. Additional studies show that, in the RAGE ligand, the high mobility group box 1 (HMGB1) protein plays an important role in chemoresistance against the cytotoxic agent gemcitabine by promoting cell survival through increased autophagy. We hypothesized that blocking the RAGE/HMGB1 interaction would enhance the cytotoxic effect of gemcitabine by reducing cell survival and autophagy. Using a preclinical mouse model of PDAC and a monoclonal antibody (IgG 2A11) as a RAGE inhibitor, we demonstrate that RAGE inhibition concurrent with gemcitabine treatment enhanced the cytotoxic effect of gemcitabine. The combination of IgG 2A11 and gemcitabine resulted in decreased autophagy compared to treatment with gemcitabine combined with control antibodies. Notably, we also observed that RAGE inhibition protected against excessive weight loss during treatment with gemcitabine. Our data suggest that the combination of gemcitabine with a RAGE inhibitor could be a promising therapeutic approach for the treatment of pancreatic cancer and needs to be further investigated.

A Unique Anti-Cancer 3-Styrylchromone Suppresses Inflammatory Response via HMGB1-RAGE Signaling

Background: High mobility group box 1 (HMGB1)-receptor for advanced glycation endo-products (RAGE) axis serves as a key player in linking inflammation and carcinogenesis. Recently, papaverine was revealed to suppress the HMGB1-RAGE inflammatory signaling pathway and cancer cell proliferation. Therefore, a dual suppressor targeting this axis is expected to become a new type of therapeutic agent to treat cancer. Methods: Papaverine 3D pharmacophore mimetic compounds were selected by the LigandScout software from our in-house, anti-cancer chemical library and assessed for their anti-inflammatory activities by a HMGB1-RAGE-mediated interleukin-6 production assay using macrophage-like RAW264.7 cells. Molecular-biological analyses, such as Western blotting, were performed to clarify the mechanism of action. Results: A unique 6-methoxy-3-hydroxy-styrylchromone was found to possess potent anti-inflammatory and anti-cancer activities via the suppression of the HMGB1-RAGE-extracellular signal-regulated kinase 1/2 signaling pathway. Furthermore, the 3D pharmacophore-activity relationship analyses revealed that the hydroxyl group at the C4′ position of the benzene ring in a 3-styryl moiety was significant in its dual suppressive effects. Conclusions: These findings indicated that this compound may provide a valuable scaffold for the development of a new type of anti-cancer drug possessing anti-inflammatory activity and as a tool for understanding the link between inflammation and carcinogenesis.

S100A7 promotes the development of human endometriosis by activating NF-κB signaling pathway in endometrial stromal cells

Endometriosis (EM) is a chronic inflammatory disease affecting women aged between 23 and 42 years with a prevalence of 6%-10%. S100A7, a member of the S100 protein family, has been implicated in promoting inflammation. However, the role of S100A7 in EM and its underlying mechanism remain to be elucidated. S100A7 was silenced or overexpressed in primary endometrial stromal cells (ESCs). Cell proliferation was determined using a Cell Counting Kit-8. Cell cycle/apoptosis was monitored using a flow cytometer. Cell invasion was studied by a Transwell assay. Quantitative RT-PCR and Western blot analyses were used to evaluate gene expression. S100A7 and NF-κB expression is increased in both endometriotic tissue and ESCs from women with EM. The expression of S100A7 is correlated with the expression of NF-κB. S100A7 knockdown inhibits ESCs proliferation, cell cycle progression, cell invasion, and inflammation, but promotes cell apoptosis in an NF-κB dependent manner. In contrast, S100A7 overexpression demonstrated an inverse effect. S100A7 is increased in both endometriotic tissue and ESCs from women with EM. S100A7 overexpression contributes to EM through increasing ESCs proliferation, cell cycle progression, cell invasion, and inflammation, and inhibiting cell apoptosis in the NF-κB dependent manner. These findings highlight the importance of S100A7/NF-κB signaling in EM and provide new insights into therapeutic strategies for EM.