The receptor RAGE: Bridging inflammation and cancer

Diabetes Driven Oncogenesis and Anticancer Potential of Repurposed Antidiabetic Drug: A Systemic Review

Diabetes and cancer are two prevalent disorders, pose significant public health challenges and contribute substantially to global mortality rates, with solely 10 million reported cancer-related deaths in 2020. This review explores the pathological association between diabetes and diverse cancer progressions, examining molecular mechanisms and potential therapeutic intersections. From altered metabolic landscapes to dysregulated signaling pathways, the intricate links are delineated, offering a comprehensive understanding of diabetes as a modulator of tumorigenesis. Cancer cells develop drug resistance through mechanisms like enhanced drug efflux, genetic mutations, and altered drug metabolism, allowing them to survive despite chemotherapeutic agent. Glucose emerges as a pivotal player in diabetes progression, and serving as a crucial energy source for cancer cells, supporting their biosynthetic needs and adaptation to diverse microenvironments. Glycation, a non-enzymatic process that produces advanced glycation end products (AGEs), has been linked to the etiology of cancer and has been shown in a number of tumor forms, such as leiomyosarcomas, adenocarcinomas, and squamous cell carcinomas. Furthermore, in aggressive and metastatic breast cancer, the receptor for AGEs (RAGE) is increased, which may increase the malignancy of the tumor. Reprogramming glucose metabolism manifests as hallmark cancer features, including accelerated cell proliferation, angiogenesis, metastasis, and evasion of apoptosis. This manuscript encapsulates the dual narrative of diabetes as a driver of cancer progression and the potential of repurposed antidiabetic drugs as formidable countermeasures. The amalgamation of mechanistic understanding and clinical trial outcomes establishes a robust foundation for further translational research and therapeutic advancements in the dynamic intersection of diabetes and 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.

Major endothelial damage markers identified from hemadsorption filters derived from treated patients with septic shock - endoplasmic reticulum stress and bikunin may play a role

Introduction

In septic patients the damage of the endothelial barrier is decisive leading to circulatory septic shock with disseminated vascular coagulation, edema and multiorgan failure. Hemadsorption therapy leads to rapid resolution of clinical symptoms. We propose that the isolation of proteins adsorbed to hemadsorption devices contributes to the identification of mediators responsible for endothelial barrier dysfunction.

Material and methods

Plasma materials enriched to hemadsorption filters (CytoSorb®) after therapy of patients in septic shock were fractionated and functionally characterized for their effect on cell integrity, viability, proliferation and ROS formation by human endothelial cells. Fractions were further studied for their contents of oxidized nucleic acids as well as peptides and proteins by mass spectrometry.

Results

Individual fractions exhibited a strong effect on endothelial cell viability, the endothelial layer morphology, and ROS formation. Fractions with high amounts of DNA and oxidized DNA correlated with ROS formation in the target endothelium. In addition, defined proteins such as defensins (HNP-1), SAA1, CXCL7, and the peptide bikunin were linked to the strongest additive effects in endothelial damage.

Conclusion

Our results indicate that hemadsorption is efficient to transiently remove strong endothelial damage mediators from the blood of patients with septic shock, which explains a rapid clinical improvement of inflammation and endothelial function. The current work indicates that a combination of stressors leads to the most detrimental effects. Oxidized ssDNA, likely derived from mitochondria, SAA1, the chemokine CXCL7 and the human neutrophil peptide alpha-defensin 1 (HNP-1) were unique for their significant negative effect on endothelial cell viability. However, the strongest damage effect occurred, when, bikunin - cleaved off from alpha-1-microglobulin was present in high relative amounts (>65%) of protein contents in the most active fraction. Thus, a relevant combination of stressors appears to be removed by hemadsorption therapy which results in fulminant and rapid, though only transient, clinical restitution.

Association of total and different food-derived advanced glycation end-products with risks of all-cause and cause-specific mortality

Background: advanced glycation end-products (AGEs), formed through a series of non-enzymatic reactions, can promote inflammation and oxidative stress. Their accumulation in the body has been linked to cardiovascular disease (CVD) and cancer. However, the association of total AGEs and AGEs from different food sources with risks of all-cause, CVD, and cancer mortality is still unknown. Methods: we conducted a prospective cohort study of a nationally representative sample of 22 124 participants from the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and NHANES 2003-2006. A food frequency questionnaire (FFQ) was utilized to calculate total and different food-derived AGE intake. Associations between various dietary AGE scores and the risk of all-cause, CVD, and cancer mortality were assessed by weighted Cox proportional hazard regression models. Results: over a median follow-up period of 27.1 years, we found that in the general population, AGE scores of both baked foods and meat were risk factors for all-cause, CVD, and cancer mortality. Specially, higher AGE scores in total and those derived from 10 of the 13 food groups were statistically associated with an increased risk of CVD mortality. Egg-, fruit-, and vegetable-derived AGE scores were positively correlated with the risk of cancer mortality. Additionally, there were positive multiplicative and additive interactions between smoking and meat-derived AGE scores on all-cause mortality. Conclusions: high amounts of AGE consumption is associated with an increased risk of CVD mortality, and meat and baked food-derived AGEs were positively linked to all-cause, CVD, and cancer mortalities. Adherence to unhealthy lifestyles, such as smoking, may increase mortality from leading causes in individuals with AGE-enriched diet habits.

Dietary and serum advanced glycation end-products and clinical outcomes in breast cancer

One in five women with breast cancer will relapse despite ideal treatment. Body weight and physical activity are strongly associated with recurrence risk, thus lifestyle modification is an attractive strategy to improve prognosis. Trials of dietary modification in breast cancer are promising but the role of specific diets is unclear, as is whether high-quality diet without weight loss can impact prognosis. Advanced glycation end-products (AGEs) are compounds produced in the body during sugar metabolism. Exogenous AGEs, such as those found in food, combined with endogenous AGEs, make up the total body AGE load. AGEs deposit in tissues over time impacting cell signaling pathways and altering protein functions. AGEs can be measured or estimated in the diet and measured in blood through their metabolites. Studies demonstrate an association between AGEs and breast cancer risk and prognosis. Here, we review the clinical data on dietary and serum AGEs in breast cancer.

Soluble receptor for advanced glycation end products (sRAGE) is associated with obesity rates: a systematic review and meta-analysis of cross-sectional study

BACKGROUND

Several studies have highlighted the possible positive effects of soluble receptor for advanced glycation end products (sRAGE) against obesity. However, due to their inconsistent results, this systematic review and meta-analysis aimed to quantitatively evaluate and critically review the results of studies evaluating the relationship between sRAGE with obesity among adult population.

METHODS

In the systematic search, the eligibility criteria were as follows: studies conducted with a cross-sectional design, included apparently healthy adults, adults with obesity, or obesity-related disorders, aged over 18 years, and evaluated the association between general or central obesity indices with sRAGE.

RESULTS

Our systematic search in electronic databases, including PubMed, Scopus, and Embase up to 26 October, 2023 yielded a total of 21,612 articles. After removing duplicates, screening the titles and abstracts, and reading the full texts, 13 manuscripts were included in the final meta-analysis. According to our results, those at the highest category of circulating sRAGE concentration with median values of 934.92 pg/ml of sRAGE, had 1.9 kg/m2 lower body mass index (BMI) (WMD: -1.927; CI: -2.868, -0.986; P < 0.001) compared with those at the lowest category of sRAGE concentration with median values of 481.88 pg/ml. Also, being at the highest sRAGE category with the median values of 1302.3 pg/ml sRAGE, was accompanied with near 6 cm lower waist circumference (WC) (WMD: -5.602; CI: -8.820, -2.383; P < 0.001 with 86.4% heterogeneity of I2) compared with those at the lowest category of sRAGE concentration with median values of 500.525 pg/ml. Individuals with obesity had significantly lower circulating sRAGE concentrations (WMD: -135.105; CI: -256.491, -13.72; P = 0.029; with 79.5% heterogeneity of I2). According to the subgrouping and meta-regression results, country and baseline BMI were possible heterogeneity sources. According to Begg's and Egger's tests and funnel plots results, there was no publication bias.

CONCLUSION

According to our results, higher circulating sRAGE concentrations was associated with lower BMI and WC among apparently healthy adults. Further randomized clinical trials are warranted for possible identification of causal associations.

Protein Advanced Glycation End Products and Their Implications in Pancreatic Cancer

Protein advanced glycation end products (AGE) formed by nonenzymatic glycation can disrupt the normal structure and function of proteins, and stimulate the receptor for AGEs (RAGE), triggering intricate mechanisms that are etiologically related to various chronic diseases, including pancreatic cancer. Many common risk factors of pancreatic cancer are the major sources for the formation of protein AGEs and glycative stress in the human body. Abnormal accumulation of protein AGEs can impair the cellular proteome and promote AGE-RAGE driven pro-inflammatory signaling cascades, leading to increased oxidative stress, protease resistance, protein dysregulation, transcription activity of STAT, NF-κB, and AP-1, aberrant status in ubiquitin-proteasome system and autophagy, as well as other molecular events that are susceptible for the carcinogenic transformation towards the development of neoplasms. Here, we review studies to highlight our understanding in the orchestrated molecular events in bridging the impaired proteome, dysregulated functional networks, and cancer hallmarks initiated upon protein AGE formation and accumulation in pancreatic cancer.

Discovery of Potential RAGE inhibitors using Receptor-Based Pharmacophore Modeling, High Throughput Virtual Screening and Docking Studies

Receptor for Advanced Glycation End products (RAGE) is a transmembrane receptor that can bind to various endogenous and exogenous ligands and initiate the inflammatory downstream signaling pathways. So far RAGE has been involved in various disorders including cardiovascular and neurodegenerative diseases, cancer, and diabetes. Blocking the interactions between RAGE and its ligands is a therapeutic approach to treat these conditions. In this context, we effectively utilized the receptor-based-pharmacophore modeling to discover structurally diverse molecular compounds having potential to effectively bind with RAGE. Two pharmacophore models were developed on V-domain of RAGE using Phase application of Schrodinger suite. The developed pharmacophoric features were used for screening of 1.8 million drug-like molecules downloaded from ChEMBL database. The molecules were scrutinized according to their molecular weight as well as clogP values. Phase screening was performed to find out the molecules that matched the developed pharmacophoric features that were further selected to analyze their binding modes using high-throughput virtual screening, extra precision docking studies and MM-GBSA ΔG binding calculations. These analyses provided ten hit RAGE inhibitory molecules that can bind to two different shallow binding sites on the V-domain of RAGE. Among the obtained compounds two compounds ChEMBL501494 and ChEMBL4081874 were found with best binding free energies that proved their receptor-ligand complex stability within their respective binding cavity on RAGE. Therefore, these molecules could be utilized for further designing and optimizing the future class of potential RAGE inhibitors.

RAGE as a Novel Biomarker for Prostate Cancer: A Systematic Review and Meta-Analysis

The receptor for advanced glycation end-products (RAGE) has been implicated in driving prostate cancer (PCa) growth, aggression, and metastasis through the fueling of chronic inflammation in the tumor microenvironment. This systematic review and meta-analysis summarizes and analyzes the current clinical and preclinical data to provide insight into the relationships among RAGE levels and PCa, cancer grade, and molecular effects. A multi-database search was used to identify original clinical and preclinical research articles examining RAGE expression in PCa. After screening and review, nine clinical and six preclinical articles were included. The associations of RAGE differentiating benign prostate hyperplasia (BPH) or normal prostate from PCa and between tumor grades were estimated using odds ratios (ORs) and associated 95% confidence intervals (CI). Pooled estimates were calculated using random-effect models due to study heterogeneity. The clinical meta-analysis found that RAGE expression was highly likely to be increased in PCa when compared to BPH or normal prostate (OR: 11.3; 95% CI: 4.4-29.1) and that RAGE was overexpressed in high-grade PCa when compared to low-grade PCa (OR: 2.5; 95% CI: 1.8-3.4). In addition, meta-analysis estimates of preclinical studies performed by albatross plot generation found robustly positive associations among RAGE expression/activation and PCa growth and metastatic potential. This review demonstrates that RAGE expression is strongly tied to PCa progression and can serve as an effective diagnostic target to differentiate between healthy prostate, low-grade PCa, and high-grade PCa, with potential theragnostic applications.

Inhibition of advance glycation end products formation, gastrointestinal digestion, absorption and toxicity: A comprehensive review

Advanced glycation end-products (AGEs) are the final products of the non-enzymatic interaction between reducing sugars and amino groups in proteins, lipids and nucleic acids. In numerous diseases, such as diabetes, neuropathy, atherosclerosis, aging, nephropathy, retinopathy, and chronic renal illness, accumulation of AGEs has been proposed as a pathogenic mechanism of inflammation, oxidative stress, and structural tissue damage leading to chronic vascular issues. Current studies on the inhibition of AGEs mainly focused on food processing. However, there are few studies on the inhibition of AGEs during digestion, absorption and metabolism although there are still plenty of AGEs in our body with our daily diet. This review comprehensively expounded AGEs inhibition mechanism based on the whole process of digestion, absorption and metabolism by polyphenols, amino acids, hydrophilic colloid, carnosine and other new anti-glycation agents. Our study will provide a ground-breaking perspective on mediation or inhibition AGEs.

Exploring the molecular interactions and binding affinity of resveratrol and calcitriol with RAGE and its intracellular proteins and kinases involved in colorectal cancer

Colorectal cancer (CRC) burden is progressively increasing in young population due to dietary and lifestyle pattern. Advanced glycation end products (AGEs), one of the dietary compounds, form complex aggregates with proteins, lipids, and nucleic acids distorting their structure and function. AGE's pro-tumorigenic role is mediated through the receptor for AGEs (RAGE) triggering an array of signaling pathways. The current study aimed to target AGE-RAGE axis signaling proteins and kinases at multiple levels with calcitriol (CAL) and trans-resveratrol (RES) through in silico analysis using molecular docking (MD), molecular dynamic simulation(MDS), MM-PBSA analysis, and in vitro study. In silico analysis of CAL and RES showed significant binding affinity toward RAGE and its signaling proteins such as NF-kB, PI3K/AKT, ERK1/2, and PKC compared to its reference inhibitors through better hydrogen, hydrophobic, pi-pi stacking interactions. MD and MDS studies have revealed stable and compact protein-ligand complexes. Binding free energies of protein-ligand complex were estimated using MM/PBSA analysis thatprovided an assessment of overall interacting free energies of complexes and revealed the presence of low binding energy within the active site. Furthermore, in the in vitro study, methylglyoxal (MG), an AGE-precursor showed a proliferative effect on HCT116, however, CAL and RES showed an inhibitory effect against MG induced effect with an IC50 value of 51 nM and 110 µM respectively. Thus, the study suggests the possible target binding sites of AGE-RAGE signaling proteins and kinases with CAL and RES, thereby exploiting it for developing CAL with RES as adjuvant therapy along with chemo drug for CRC.Communicated by Ramaswamy H. Sarma.

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.

RAGE inhibitor TTP488 (Azeliragon) suppresses metastasis in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a highly aggressive and metastatic cancer subtype, which is generally untreatable once it metastasizes. We hypothesized that interfering with the Receptor for Advanced Glycation End-products (RAGE) signaling with the small molecule RAGE inhibitors (TTP488/Azeliragon and FPS-ZM1) would impair TNBC metastasis and impair fundamental mechanisms underlying tumor progression and metastasis. Both TTP488 and FPS-ZM1 impaired spontaneous and experimental metastasis of TNBC models, with TTP488 reducing metastasis to a greater degree than FPS-ZM1. Transcriptomic analysis of primary xenograft tumor and metastatic tissue revealed high concordance in gene and protein changes with both drugs, with TTP488 showing greater potency against metastatic driver pathways. Phenotypic validation of transcriptomic analysis by functional cell assays revealed that RAGE inhibition impaired TNBC cell adhesion to multiple extracellular matrix proteins (including collagens, laminins, and fibronectin), migration, and invasion. Neither RAGE inhibitor impaired cellular viability, proliferation, or cell cycle in vitro. Proteomic analysis of serum from tumor-bearing mice revealed RAGE inhibition affected metastatic driver mechanisms, including multiple cytokines and growth factors. Further mechanistic studies by phospho-proteomic analysis of tumors revealed RAGE inhibition led to decreased signaling through critical BC metastatic driver mechanisms, including Pyk2, STAT3, and Akt. These results show that TTP488 impairs metastasis of TNBC and further clarifies the signaling and cellular mechanisms through which RAGE mediates metastasis. Importantly, as TTP488 displays a favorable safety profile in human studies, our study provides the rationale for evaluating TTP488 in clinical trials to treat or prevent metastatic TNBC.

Dietary Advanced Glycation End Products: Their Role in the Insulin Resistance of Aging

Insulin resistance (IR) is commonly observed during aging and is at the root of many of the chronic nontransmissible diseases experienced as people grow older. Many factors may play a role in causing IR, but diet is undoubtedly an important one. Whether it is total caloric intake or specific components of the diet, the factors responsible remain to be confirmed. Of the many dietary influences that may play a role in aging-related decreased insulin sensitivity, advanced glycation end products (AGEs) appear particularly important. Herein, we have reviewed in detail in vitro, animal, and human evidence linking dietary AGEs contributing to the bodily burden of AGEs with the development of IR. We conclude that numerous small clinical trials assessing the effect of dietary AGE intake in combination with strong evidence in many animal studies strongly suggest that reducing dietary AGE intake is associated with improved IR in a variety of disease conditions. Reducing AGE content of common foods by simple changes in culinary techniques is a feasible, safe, and easily applicable intervention in both health and disease. Large-scale clinical trials are still needed to provide broader evidence for the deleterious role of dietary AGEs in chronic disease.

Atherosclerosis and Inflammation: Insights from the Theory of General Pathological Processes

Recent advances have greatly improved our understanding of the molecular mechanisms behind atherosclerosis pathogenesis. However, there is still a need to systematize this data from a general pathology perspective, particularly with regard to atherogenesis patterns in the context of both canonical and non-classical inflammation types. In this review, we analyze various typical phenomena and outcomes of cellular pro-inflammatory stress in atherosclerosis, as well as the role of endothelial dysfunction in local and systemic manifestations of low-grade inflammation. We also present the features of immune mechanisms in the development of productive inflammation in stable and unstable plaques, along with their similarities and differences compared to canonical inflammation. There are numerous factors that act as inducers of the inflammatory process in atherosclerosis, including vascular endothelium aging, metabolic dysfunctions, autoimmune, and in some cases, infectious damage factors. Life-critical complications of atherosclerosis, such as cardiogenic shock and severe strokes, are associated with the development of acute systemic hyperinflammation. Additionally, critical atherosclerotic ischemia of the lower extremities induces paracoagulation and the development of chronic systemic inflammation. Conversely, sepsis, other critical conditions, and severe systemic chronic diseases contribute to atherogenesis. In summary, atherosclerosis can be characterized as an independent form of inflammation, sharing similarities but also having fundamental differences from low-grade inflammation and various variants of canonical inflammation (classic vasculitis).

Differential gene expression analysis of RAGE-S100A6 complex for target selection and the design of novel inhibitors for anticancer drug discovery

Receptor for advanced glycation end products (RAGE), a member of the immunoglobulin family, interactions with its ligands trigger downstream signaling and induce an inflammatory response linked to diabetes, inflammation, carcinogenesis, cardiovascular disease, and a variety of other human disorders. The interaction of RAGE and S100A6 has been associated with a variety of malignancies. For the control of RAGE-related illnesses, there is a great demand for more specialized drug options. To identify the most effective target for combating human malignancies associated with RAGE-S100A6 complex, we conducted single and differential gene expression analyses of S100A6 and RAGE, comparing normal and malignant tissues. Further, a structure-based virtual screening was conducted using the ZINC15 database. The chosen compounds were then subjected to a molecular docking investigation on the RAGE active site region, recognized by the various cancer-related RAGE ligands. An optimized RAGE structure was screened against a library of drug-like molecules. The screening results suggested that three promising compounds were presented as the top acceptable drug-like molecules with a high binding affinity at the RAGE V-domain catalytic region. We depicted that these compounds may be potential RAGE inhibitors and could be used to produce a successful medication against human cancer and other RAGE-related diseases based on their various assorted parameters, binding energy, hydrogen bonding, ADMET characteristics, etc. MD simulation on a time scale of 50 ns was used to test the stability of the RAGE-inhibitor complexes. Therefore, targeting RAGE and its ligands using these drug-like molecules may be an effective therapeutic approach.

RAGE Inhibitors for Targeted Therapy of Cancer: A Comprehensive Review

The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin family that is overexpressed in several cancers. RAGE is highly expressed in the lung, and its expression increases proportionally at the site of inflammation. This receptor can bind a variety of ligands, including advanced glycation end products, high mobility group box 1, S100 proteins, adhesion molecules, complement components, advanced lipoxidation end products, lipopolysaccharides, and other molecules that mediate cellular responses related to acute and chronic inflammation. RAGE serves as an important node for the initiation and stimulation of cell stress and growth signaling mechanisms that promote carcinogenesis, tumor propagation, and metastatic potential. In this review, we discuss different aspects of RAGE and its prominent ligands implicated in cancer pathogenesis and describe current findings that provide insights into the significant role played by RAGE in cancer. Cancer development can be hindered by inhibiting the interaction of RAGE with its ligands, and this could provide an effective strategy for cancer treatment.

Increased cerebrospinal fluid S100B protein levels in patients with trigeminal neuralgia and hemifacial spasm

BACKGROUND

The pathophysiology of neurovascular compression syndrome has not been fully elucidated, and cerebrospinal fluid levels of nerve tissue-related markers involved in this disorder have not yet been reported.

METHODS

We measured cerebrospinal fluid levels of S100B protein, neuron-specific enolase, and myelin basic protein in 21 patients with trigeminal neuralgia, 9 patients with hemifacial spasms, and 10 patients with non-ruptured intracranial aneurysms (control). Cerebrospinal fluid levels of these markers were determined using commercially available assay kits.

RESULTS

Both trigeminal neuralgia and hemifacial spasm groups showed significantly increased cerebrospinal fluid levels of S100B compared with the control group (1120 [IQR 391-1420], 766 [IQR 583-1500], and 255 [IQR 190-285] pg/mL, respectively; p = 0.001). There were no statistically significant differences in cerebrospinal fluid levels of neuron-specific enolase or myelin basic protein among the groups.

CONCLUSION

Cerebrospinal fluid S100B levels were significantly higher in patients with trigeminal neuralgia and hemifacial spasm than in controls, which suggests the involvement of S100B in the underlying pathophysiology of neurovascular compression syndrome.

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.

Transcriptomic discovery of a theranostic signature (SERPINE1/MMP3/COL1A1/SPP1) for head and neck squamous cell carcinomas and identification of antrocinol as a candidate drug

Head and neck squamous cell carcinomas (HNSCC) are prevalent malignancies with a disappointing prognosis, necessitating the search for theranostic biomarkers for better management. Based on a meta-analysis of transcriptomic data containing ten clinical datasets of HNSCC and matched nonmalignant samples, we identified SERPINE1/MMP3/COL1A1/SPP1 as essential hub genes as the potential theranostic biomarkers. Our analysis suggests these hub genes are associated with the extracellular matrix, peptidoglycans, cell migration, wound-healing processes, complement and coagulation cascades, and the AGE-RAGE signaling pathway within the tumor microenvironment. Also, these hub genes were associated with tumor-immune infiltrating cells and immunosuppressive phenotypes of HNSCC. Further investigation of The Cancer Genome Atlas (TCGA) cohorts revealed that these hub genes were associated with staging, metastasis, and poor survival in HNSCC patients. Molecular docking simulations were performed to evaluate binding activities between the hub genes and antrocinol, a novel small-molecule derivative of an anticancer phytochemical antrocin previously discovered by our group. Antrocinol showed high affinities to MMP3 and COL1A1. Notably, antrocinol presented satisfactory drug-like and ADMET properties for therapeutic applications. These results hinted at the potential of antrocinol as an anti-HNSCC candidate via targeting MMP3 and COL1A1. In conclusion, we identified hub genes: SERPINE1/MMP3/COL1A1/SPP1 as potential diagnostic biomarkers and antrocinol as a potential new drug for HNSCC.

Integrated Molecular Analysis Reveals 2 Distinct Subtypes of Pure Seminoma of the Testis

Objective:

Testicular germ cell tumors (TGCT) are the most common solid malignancy in adolescent and young men, with a rising incidence over the past 20 years. Overall, TGCTs are second in terms of the average life years lost per person dying of cancer, and clinical therapeutics without adverse long-term side effects are lacking. Platinum-based regimens for TGCTs have heterogeneous outcomes even within the same histotype that frequently leads to under- and over-treatment. Understanding of molecular differences that lead to diverse outcomes of TGCT patients may improve current treatment approaches. Seminoma is the most common subtype of TGCTs, which can either be pure or present in combination with other histotypes.

Methods:

Here we conducted a computational study of 64 pure seminoma samples from The Cancer Genome Atlas, applied consensus clustering approach to their transcriptomic data and revealed 2 clinically relevant seminoma subtypes: seminoma subtype 1 and 2.

Results:

Our analysis identified significant differences in pluripotency stage, activity of double stranded DNA breaks repair mechanisms, rates of loss of heterozygosity, and expression of lncRNA responsible for cisplatin resistance between the subtypes. Seminoma subtype 1 is characterized by higher pluripotency state, while subtype 2 showed attributes of reprograming into non-seminomatous TGCT. The seminoma subtypes we identified may provide a molecular underpinning for variable responses to chemotherapy and radiation.

Conclusion:

Translating our findings into clinical care may help improve risk stratification of seminoma, decrease overtreatment rates, and increase long-term quality of life for TGCT survivors.

PPAR-γ Partial Agonists in Disease-Fate Decision with Special Reference to Cancer

Peroxisome proliferator-activated receptor-γ (PPAR-γ) has emerged as one of the most extensively studied transcription factors since its discovery in 1990, highlighting its importance in the etiology and treatment of numerous diseases involving various types of cancer, type 2 diabetes mellitus, autoimmune, dermatological and cardiovascular disorders. Ligands are regarded as the key determinant for the tissue-specific activation of PPAR-γ. However, the mechanism governing this process is merely a contradictory debate which is yet to be systematically researched. Either these receptors get weakly activated by endogenous or natural ligands or leads to a direct over-activation process by synthetic ligands, serving as complete full agonists. Therefore, fine-tuning on the action of PPAR-γ and more subtle modulation can be a rewarding approach which might open new avenues for the treatment of several diseases. In the recent era, researchers have sought to develop safer partial PPAR-γ agonists in order to dodge the toxicity induced by full agonists, akin to a balanced activation. With a particular reference to cancer, this review concentrates on the therapeutic role of partial agonists, especially in cancer treatment. Additionally, a timely examination of their efficacy on various other disease-fate decisions has been also discussed.

Methylglyoxal and Its Adducts: Induction, Repair, and Association with Disease

Metabolism is an essential part of life that provides energy for cell growth. During metabolic flux, reactive electrophiles are produced that covalently modify macromolecules, leading to detrimental cellular effects. Methylglyoxal (MG) is an abundant electrophile formed from lipid, protein, and glucose metabolism at intracellular levels of 1-4 μM. MG covalently modifies DNA, RNA, and protein, forming advanced glycation end products (MG-AGEs). MG and MG-AGEs are associated with the onset and progression of many pathologies including diabetes, cancer, and liver and kidney disease. Regulating MG and MG-AGEs is a potential strategy to prevent disease, and they may also have utility as biomarkers to predict disease risk, onset, and progression. Here, we review recent advances and knowledge surrounding MG, including its production and elimination, mechanisms of MG-AGEs formation, the physiological impact of MG and MG-AGEs in disease onset and progression, and the latter in the context of its receptor RAGE. We also discuss methods for measuring MG and MG-AGEs and their clinical application as prognostic biomarkers to allow for early detection and intervention prior to disease onset. Finally, we consider relevant clinical applications and current therapeutic strategies aimed at targeting MG, MG-AGEs, and RAGE to ultimately improve patient outcomes.

Extracellular matrix mechanobiology in cancer cell migration

The extracellular matrix (ECM) is pivotal in modulating tumor progression. Besides chemically stimulating tumor cells, it also offers physical support that orchestrates the sequence of events in the metastatic cascade upon dynamically modulating cell mechanosensation. Understanding this translation between matrix biophysical cues and intracellular signaling has led to rapid growth in the interdisciplinary field of cancer mechanobiology in the last decade. Substantial efforts have been made to develop novel in vitro tumor mimicking platforms to visualize and quantify the mechanical forces within the tissue that dictate tumor cell invasion and metastatic growth. This review highlights recent findings on tumor matrix biophysical cues such as fibrillar arrangement, crosslinking density, confinement, rigidity, topography, and non-linear mechanics and their implications on tumor cell behavior. We also emphasize how perturbations in these cues alter cellular mechanisms of mechanotransduction, consequently enhancing malignancy. Finally, we elucidate engineering techniques to individually emulate the mechanical properties of tumors that could help serve as toolkits for developing and testing ECM-targeted therapeutics on novel bioengineered tumor platforms. STATEMENT OF SIGNIFICANCE: Disrupted ECM mechanics is a driving force for transitioning incipient cells to life-threatening malignant variants. Understanding these ECM changes can be crucial as they may aid in developing several efficacious drugs that not only focus on inducing cytotoxic effects but also target specific matrix mechanical cues that support and enhance tumor invasiveness. Designing and implementing an optimal tumor mimic can allow us to predictively map biophysical cue-modulated cell behaviors and facilitate the design of improved lab-grown tumor models with accurately controlled structural features. This review focuses on the abnormal changes within the ECM during tumorigenesis and its implications on tumor cell-matrix mechanoreciprocity. Additionally, it accentuates engineering approaches to produce ECM features of varying levels of complexity which is critical for improving the efficiency of current engineered tumor tissue models.

The AGEs/RAGE Transduction Signaling Prompts IL-8/CXCR1/2-Mediated Interaction between Cancer-Associated Fibroblasts (CAFs) and Breast Cancer Cells

Advanced glycation end products (AGEs) and the cognate receptor, named RAGE, are involved in metabolic disorders characterized by hyperglycemia, type 2 diabetes mellitus (T2DM) and obesity. Moreover, the AGEs/RAGE transduction pathway prompts a dysfunctional interaction between breast cancer cells and tumor stroma toward the acquisition of malignant features. However, the action of the AGEs/RAGE axis in the main players of the tumor microenvironment, named breast cancer-associated fibroblasts (CAFs), remains to be fully explored. In the present study, by chemokine array, we first assessed that interleukin-8 (IL-8) is the most up-regulated pro-inflammatory chemokine upon AGEs/RAGE activation in primary CAFs, obtained from breast tumors. Thereafter, we ascertained that the AGEs/RAGE signaling promotes a network cascade in CAFs, leading to the c-Fos-dependent regulation of IL-8. Next, using a conditioned medium from AGEs-exposed CAFs, we determined that IL-8/CXCR1/2 paracrine activation induces the acquisition of migratory and invasive features in MDA-MB-231 breast cancer cells. Altogether, our data provide new insights on the involvement of IL-8 in the AGEs/RAGE transduction pathway among the intricate connections linking breast cancer cells to the surrounding stroma. Hence, our findings may pave the way for further investigations to define the role of IL-8 as useful target for the better management of breast cancer patients exhibiting metabolic disorders.

Neutrophil Extracellular Traps and Pancreatic Cancer Development: A Vicious Cycle

Neutrophil extracellular traps (NETs) are a neutrophil-generated extracellular network of chromatin and chromatin-bound molecules with antimicrobial potency. Recent data suggest that NETs are associated with cancer progression and cancer-associated hypercoagulability. Pancreatic adenocarcinoma (PDAC) is a lethal type of cancer in which hypercoagulability and cancer-related thrombosis are among the main complications. In the current report, we summarize the available data on the interplay between NET formation and PDAC development. We conclude that NETs support a dual role during PDAC progression and metastasis. Their formation is on the one hand an important event that shapes the cancer microenvironment to support cancer cell proliferation, invasion and metastasis. On the other hand, NETs may lead to cancer-associated thrombosis. Both mechanisms seem to be dependent on distinct molecular mechanisms that link inflammation to cancer progression. Collectively, NET formation may contribute to the pathogenesis of PDAC, while during cancer development, the proinflammatory environment enables the induction of new NETs and thrombi, forming a vicious cycle. We suggest that targeting NET formation may be an effective mechanism to inhibit both PDAC development and the accompanying hypercoagulability.

Therapeutic potential of targeting the receptor for advanced glycation end products (RAGE) by small molecule inhibitors

Receptor for advanced glycation end products (RAGE) is a 45 kDa transmembrane receptor of immunoglobulin family that can bind to various endogenous and exogenous ligands and initiate the inflammatory downstream signaling pathways. RAGE is involved in various disorders including cardiovascular and neurodegenerative diseases, cancer, and diabetes. This review summarizes the structural features of RAGE and its various isoforms along with their pathological effects. Mainly, the article emphasized on the translational significance of antagonizing the interactions of RAGE with its ligands using small molecules reported in the last 5 years and discusses future approaches that could be employed to block the interactions in the treatment of chronic inflammatory ailments. The RAGE inhibitors described in this article could prove as a powerful approach in the management of immune‐inflammatory diseases. A critical review of the literature suggests that there is a dire need to dive deeper into the molecular mechanism of action to resolve critical issues that must be addressed to understand RAGE‐targeting therapy and long‐term blockade of RAGE in human diseases.

Case Report: Malignant Melanoma Associated With COVID-19: A Coincidence or a Clue?

Following SARS-CoV-2 infection in humans, there is upregulation of proinflammatory molecules S100 calcium binding protein B (S100B), high-mobility group box-1 (HMGB1), osteopontin (OPN), tumor necrosis factor alpha (TNF-α), and other cytokines that promote hyperinflammation. The same immunoregulatory proteins that fuel the COVID-19 “cytokine storm” are also produced by melanoma cells and various other cancers to promote tumorigenesis. We report three cases of malignant melanoma (MM) associated with severe COVID-19, the first two with amelanotic melanoma and the third with hypopigmented melanoma. It is noteworthy that we did not search for these cases. Patient 1 is a personal acquaintance and cases 2 and 3 were hospitalized and worked at our rehabilitation center, respectively. We hypothesize that SARS-CoV-2 induced inflammatory tumorigenic proteins in the microenvironment that may have contributed to the de novo development (case 1), aggressive growth (case 2), or recurrence (case 3) of these malignant tumors. Moreover, high concentrations of the same proinflammatory proteins found in the “cytokine storm” associated with COVID-19, including TNF-α, interleukin (IL)-1α, IL-1β, IL-6, and ferritin, also induce skin depigmentation or hypopigmentation by interfering with tyrosinase synthesis, the enzyme that catalyzes the rate-limiting step of pigmentation. Hence, the marked elevation of the biological effectors that decrease skin pigmentation may also reduce pigmentation in MMs, resulting in amelanotic or hypopigmented lesions. Although it is certainly possible that the occurrence of melanoma following COVID-19 is coincidental, the ability of SARS-CoV-2 to increase expression of proinflammatory and tumorigenic molecules warrants further investigations to determine if there is an association between these disease processes or implications for patients with melanoma or other cancers who develop COVID-19.

Dietary advanced glycation end products and cancer risk in Japan: from the Takayama study

Few large epidemiological studies have evaluated the association between dietary advanced glycation end products (AGEs) and cancer risk. We evaluated the relationship between dietary AGE intake and the incidence of total cancer and site‐specific cancers in a population‐based prospective study in Japan. Participants were 14,173 men and 16,549 women who were 35 years of age or older in 1992. Dietary intake was assessed via a validated food frequency questionnaire. Intake of the AGE N^ε‐carboxymethyl‐lysine (CML) was estimated using databases of CML content in foods determined using ultraperformance liquid chromatography–tandem mass spectrometry. Cancer incidence was confirmed through regional population‐based cancer registries. During a mean follow‐up period of 13.3 years, 1954 men and 1477 women developed cancer. We did not observe a significant association between CML intake and the risk of total cancer in men or women. In men, compared with the lowest quartile of CML intake, the hazard ratios of liver cancer for the second, third, and highest quartiles were 1.69 (95% CI: 0.92–3.10), 1.48 (95% CI: 0.77–2.84), and 2.10 (95% CI: 1.10–3.98; trend p = 0.04). Conversely, a decreased relative risk of male stomach cancer was observed for the second and highest quartiles of CML intake versus the lowest quartile, with hazard ratios of 0.73 and 0.67, respectively (trend p = 0.08). Our finding on the potential harmfulness of consuming AGEs on liver cancer risk is intriguing and warrants further study.

SARS-CoV-2 Causes Lung Inflammation through Metabolic Reprogramming and RAGE

Clinical studies indicate that patients infected with SARS-CoV-2 develop hyperinflammation, which correlates with increased mortality. The SARS-CoV-2/COVID-19-dependent inflammation is thought to occur via increased cytokine production and hyperactivity of RAGE in several cell types, a phenomenon observed for other disorders and diseases. Metabolic reprogramming has been shown to contribute to inflammation and is considered a hallmark of cancer, neurodegenerative diseases, and viral infections. Malfunctioning glycolysis, which normally aims to convert glucose into pyruvate, leads to the accumulation of advanced glycation end products (AGEs). Being aberrantly generated, AGEs then bind to their receptor, RAGE, and activate several pro-inflammatory genes, such as IL-1b and IL-6, thus, increasing hypoxia and inducing senescence. Using the lung epithelial cell (BEAS-2B) line, we demonstrated that SARS-CoV-2 proteins reprogram the cellular metabolism and increase pyruvate kinase muscle isoform 2 (PKM2). This deregulation promotes the accumulation of AGEs and senescence induction. We showed the ability of the PKM2 stabilizer, Tepp-46, to reverse the observed glycolysis changes/alterations and restore this essential metabolic process.

Advanced Glycation End Products and Diabetes Mellitus: Mechanisms and Perspectives

Persistent hyperglycemic state in type 2 diabetes mellitus leads to the initiation and progression of non-enzymatic glycation reaction with proteins and lipids and nucleic acids. Glycation reaction leads to the generation of a heterogeneous group of chemical moieties known as advanced glycated end products (AGEs), which play a central role in the pathophysiology of diabetic complications. The engagement of AGEs with its chief cellular receptor, RAGE, activates a myriad of signaling pathways such as MAPK/ERK, TGF-β, JNK, and NF-κB, leading to enhanced oxidative stress and inflammation. The downstream consequences of the AGEs/RAGE axis involve compromised insulin signaling, perturbation of metabolic homeostasis, RAGE-induced pancreatic beta cell toxicity, and epigenetic modifications. The AGEs/RAGE signaling instigated modulation of gene transcription is profoundly associated with the progression of type 2 diabetes mellitus and pathogenesis of diabetic complications. In this review, we will summarize the exogenous and endogenous sources of AGEs, their role in metabolic dysfunction, and current understandings of AGEs/RAGE signaling cascade. The focus of this review is to recapitulate the role of the AGEs/RAGE axis in the pathogenesis of type 2 diabetes mellitus and its associated complications. Furthermore, we present an overview of future perspectives to offer new therapeutic interventions to intervene with the AGEs/RAGE signaling pathway and to slow down the progression of diabetes-related complications.

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.

Advanced glycation end-products (AGEs) are lower in prostate tumor tissue and inversely related to proportion of West African ancestry

BACKGROUND

The metabolism of normal prostate relies on glycolysis, with prostate cancer having reduced glycolysis and increased aerobic metabolism. Advanced glycation end products (AGEs) accumulate in tissues as a result of age and glycolytic rate. Differential AGE levels were recently observed in prostate cancer tissues. Herein we sought to quantify AGEs in benign and cancer prostate tissue in a diverse cohort of patients.

METHODS

Levels of the AGE Nε-(carboxylethyl)lysine (CML) were quantified by immunohistochemistry (IHC) in a tissue microarray which consisted of 3 cores from tumor and 2 cores from benign areas from 118 patients (87 African American and 31 European American). Ancestry informative markers for African Ancestry were available for 79 patients. Epithelial and stromal areas were quantified separately using an E-cadherin mask. CML levels were compared with clinical grade group and ancestry by mixed linear effect models. Age, prostate-specific antigen (PSA) levels, body mass index (BMI), and hemoglobin A1C were included as covariates.

RESULTS

CML levels were lower in areas of the tumor, for both epithelium and surrounding stroma, compared with benign, but did not significantly change with tumor grade group. Age, PSA levels, BMI, and hemoglobin A1C did not associate with CML levels. CML levels were inversely associated with the percentage of African Ancestry in all tissues.

CONCLUSIONS

The low CML levels in cancer may reflect the reduced glycolytic state of the tissue. The inverse relationship between African Ancestry and CML levels in both benign and cancer areas suggests a state of reduced glycolysis. It is yet to be determined whether altered glycolysis and CML levels are bystanders or drivers of carcinogenesis.

Dietary Advanced Glycation End-Products and Mortality after Breast Cancer in the Women's Health Initiative

BACKGROUND

Advanced glycation end-products (AGE) are formed through nonenzymatic glycation of free amino groups in proteins or lipid. They are associated with inflammation and oxidative stress, and their accumulation in the body is implicated in chronic disease morbidity and mortality. We examined the association between postdiagnosis dietary Nε-carboxymethyl-lysine (CML)-AGE intake and mortality among women diagnosed with breast cancer.

METHODS

Postmenopausal women aged 50 to 79 years were enrolled in the Women's Health Initiative (WHI) between 1993 and 1998 and followed up until death or censoring through March 2018. We included 2,023 women diagnosed with first primary invasive breast cancer during follow-up who completed a food frequency questionnaire (FFQ) after diagnosis. Cox proportional hazards (PH) regression models estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) of association between tertiles of postdiagnosis CML-AGE intake and mortality risk from all causes, breast cancer, and cardiovascular disease.

RESULTS

After a median 15.1 years of follow-up, 630 deaths from all causes were reported (193 were breast cancer-related, and 129 were cardiovascular disease-related). Postdiagnosis CML-AGE intake was associated with all-cause (HRT3vsT1, 1.37; 95% CI, 1.09-1.74), breast cancer (HRT3vsT1, 1.49; 95% CI, 0.98-2.24), and cardiovascular disease (HRT3vsT1, 1.91; 95% CI, 1.09-3.32) mortality.

CONCLUSIONS

Higher intake of AGEs was associated with higher risk of major causes of mortality among postmenopausal women diagnosed with breast cancer.

IMPACT

Our findings suggest that dietary AGEs may contribute to the risk of mortality after breast cancer diagnosis. Further prospective studies examining dietary AGEs in breast cancer outcomes and intervention studies targeting dietary AGE reduction are needed to confirm our findings.

PPAR-γ Modulators as Current and Potential Cancer Treatments

Worldwide, cancer has become one of the leading causes of mortality. Peroxisome Proliferator-Activated Receptors (PPARs) is a family of critical sensors of lipids as well as regulators of diverse metabolic pathways. They are also equipped with the capability to promote eNOS activation, regulate immunity and inflammation response. Aside from the established properties, emerging discoveries are also made in PPAR's functions in the cancer field. All considerations are given, there exists great potential in PPAR modulators which may hold in the management of cancers. In particular, PPAR-γ, the most expressed subtype in adipose tissues with two isoforms of different tissue distribution, has been proven to be able to inhibit cell proliferation, induce cell cycle termination and apoptosis of multiple cancer cells, promote intercellular adhesion, and cripple the inflamed state of tumor microenvironment, both on transcriptional and protein level. However, despite the multi-functionalities, the safety of PPAR-γ modulators is still of clinical concern in terms of dosage, drug interactions, cancer types and stages, etc. This review aims to consolidate the functions of PPAR-γ, the current and potential applications of PPAR-γ modulators, and the challenges in applying PPAR-γ modulators to cancer treatment, in both laboratory and clinical settings. We sincerely hope to provide a comprehensive perspective on the prospect of PPAR-γ applicability in the field of cancer treatment.

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.

Problems of Pathogenesis and Pathogenetic Therapy of COVID-19 from the Perspective of the General Theory of Pathological Systems (General Pathological Processes)

The COVID-19 pandemic examines not only the state of actual health care but also the state of fundamental medicine in various countries. Pro-inflammatory processes extend far beyond the classical concepts of inflammation. They manifest themselves in a variety of ways, beginning with extreme physiology, then allostasis at low-grade inflammation, and finally the shockogenic phenomenon of "inflammatory systemic microcirculation". The pathogenetic core of critical situations, including COVID-19, is this phenomenon. Microcirculatory abnormalities, on the other hand, lie at the heart of a specific type of general pathological process known as systemic inflammation (SI). Systemic inflammatory response, cytokine release, cytokine storm, and thrombo-inflammatory syndrome are all terms that refer to different aspects of SI. As a result, the metabolic syndrome model does not adequately reflect the pathophysiology of persistent low-grade systemic inflammation (ChSLGI). Diseases associated with ChSLGI, on the other hand, are risk factors for a severe COVID-19 course. The review examines the role of hypoxia, metabolic dysfunction, scavenger receptors, and pattern-recognition receptors, as well as the processes of the hemophagocytic syndrome, in the systemic alteration and development of SI in COVID-19.

Hydroxytyrosol Selectively Affects Non-Enzymatic Glycation in Human Insulin and Protects by AGEs Cytotoxicity

Hydroxytyrosol (HT), the major phenolic compound in olive oil, is attracting increasing interest for its beneficial properties including a notable antioxidant and anti-inflammatory power. In this study, using a combination of biophysical and cell biology techniques, we have tested the role of HT in the formation of advanced glycation end-products (AGEs). AGEs have a key role in clinical sciences as they have been associated to diabetes, neurodegenerative and cardiovascular diseases. In addition, as the incidence of Alzheimer’s disease (AD) is strongly increased in diabetic patients, AGE formation is supposed to be involved in the development of the pathological hallmarks of AD. Our data show that HT selectively inhibits protein glycation reaction in human insulin, and it is able to counteract the AGE-induced cytotoxicity in human neurotypical cells by acting on SIRT1 level and oxidative stress, as well as on inflammatory response. This study identifies new beneficial properties for HT and suggests it might be a promising molecule in protecting against the AGE-induced toxicity, a key mechanism underlying the development and progression of neurodegenerative disorders.

Measurement of Advanced Glycation End Products Could Be Used as an Indicator of Unhealthy Nutrition for Colorectal Cancer Risk

The main culprit behind most cancers is the accumulation of reactive oxygen species. Glyoxal (GO) and methylglyoxal (MGO) are reactive intermediates created by food processing and they are precursors of advanced glycation end products (AGE) that cause glycative stress. We aimed to evaluate the relationship between AGE levels of healthy volunteers and treatment-naive patients diagnosed with colorectal cancer. The study consisted of patients diagnosed with colorectal cancer and healthy volunteers who underwent routine colonoscopy. The study was conducted with a total of 42 cases, 47.6% (n = 20) female. The ages of the participants in the study ranged from 41 to 82 years, and the mean was 60.57 ± 10.78 years. The GO and MGO values of the patient group were found to be significantly higher than those of the control group (p = 0.007, p = 0.001, respectively). The risk of colorectal cancer was 22 and 57 times higher in individuals with GO and MGO values above 1.25 μg/mL and 0.0095 μg/mL, respectively. The blood AGE level is closely related to diet, and it can be decreased through the appropriate improvement of diet. Thus, the measurement of AGE can be used to predict whether a person's nutrition is healthy or unhealthy and prevent increased risk of colorectal cancer.

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.

S100A4 Is Involved in Stimulatory Effects Elicited by the FGF2/FGFR1 Signaling Pathway in Triple-Negative Breast Cancer (TNBC) Cells

Triple-negative breast cancer (TNBC) is an aggressive breast tumor subtype characterized by poor clinical outcome. In recent years, numerous advancements have been made to better understand the biological landscape of TNBC, though appropriate targets still remain to be determined. In the present study, we have determined that the expression levels of FGF2 and S100A4 are higher in TNBC with respect to non-TNBC patients when analyzing “The Invasive Breast Cancer Cohort of The Cancer Genome Atlas” (TCGA) dataset. In addition, we have found that the gene expression of FGF2 is positively correlated with S100A4 in TNBC samples. Performing quantitative PCR, Western blot, CRISPR/Cas9 genome editing, promoter studies, immunofluorescence analysis, subcellular fractionation studies, and ChIP assays, we have also demonstrated that FGF2 induces in TNBC cells the upregulation and secretion of S100A4 via FGFR1, along with the ERK1/2–AKT–c-Rel transduction signaling. Using conditioned medium from TNBC cells stimulated with FGF2, we have also ascertained that the paracrine activation of the S100A4/RAGE pathway triggers angiogenic effects in vascular endothelial cells (HUVECs) and promotes the migration of cancer-associated fibroblasts (CAFs). Collectively, our data provide novel insights into the action of the FGF2/FGFR1 axis through S100A4 toward stimulatory effects elicited in TNBC cells.

Sesamin suppresses advanced glycation end products induced microglial reactivity using BV2 microglial cell line as a model

Neuroinflammation-mediated microglial reactivity is a major process, which explains the increased risk of Alzheimer's disease (AD) development in patients with Type 2 diabetes mellitus (T2DM). Advanced glycation end products (AGEs), formed by hyperglycemic condition in diabetes, is characterized as an intermediary of brain injury with diabetes through induction of microglial reactivity. Here, we explored the effect of AGEs on microglial reactivity using BV2 as a model. The NF-κB, p38 and JNK pathways were found to be important mechanism in AGEs-induced BV2 microglial reactivity. NF-κB inhibitor (BAY-11-7082), p38 inhibitor (SB203580) and JNK inhibitor (SP600125) exhibited the potential inhibition of AGEs-induced NO production. We also found that the sesamin, a major lignan found in sesame seed oils, exerts an anti-inflammatory effect under AGEs-induced microglial reactivity via suppressing the phosphorylation of NF-κB, p38 and JNK pathways. Moreover, sesamin also ameliorated AGEs-induced-receptor for advanced glycation end products (RAGE) expression. Taken together, sesamin may be a promising phytochemical compound to delay inflammatory progress by AGEs microglia function. Similarly, inhibition of AGEs-induced microglial reactivity might be potential therapeutic targets of neuroinflammation-based mechanisms in T2DM link progressive AD.

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.

Inflammatory profiles in Chilean Mapuche and non-Mapuche women with gallstones at risk of developing gallbladder cancer

Chile has high incidence rates of gallbladder cancer globally, particularly among Amerindian women, who also have a high prevalence of gallstones. We examined differences in inflammatory biomarkers between Mapuche and non-Mapuche women from the Chile Biliary Longitudinal Study, a cohort of women with ultrasound-detected gallstones. We randomly selected 200 Mapuche women frequency matched to non-Mapuche women on age and statin use Inflammatory biomarkers were analyzed using a multiplex assay and linear regression to assess associations of a priori markers (CCL20, CXCL10, IL-6, and IL-8) with ethnicity. Novel biomarkers were analyzed using exploratory factor analysis (EFA) and sufficient dimension reduction (SDR) to identify correlated marker groups, followed by linear regression to examine their association with ethnicity. The mean values of IL-8 were higher in Mapuche than non-Mapuche women (P = 0.04), while CCL20, CXCL10, and IL-6 did not differ significantly by ethnicity. EFA revealed two marker groups associated with ethnicity (P = 0.03 and P < 0.001). SDR analysis confirmed correlation between the biomarkers and ethnicity. We found higher IL-8 levels among Mapuche than non-Mapuche women. Novel inflammatory biomarkers were correlated with ethnicity and should be studied further for their role in gallbladder disease. These findings may elucidate underlying ethnic disparities in gallstones and carcinogenesis among Amerindians.

Recent Advances in Histone Glycation: Emerging role in Diabetes and Cancer

Ever increasing information on genome and proteome has offered fascinating details and new opportunities to understand the molecular biology. It is now known that histone proteins surrounding the DNA play a crucial role in the chromatin structure and function. Histones undergo a plethora of post-translational enzymatic modifications that influence nucleosome dynamics and affect DNA activity. Earlier research offered insights into the enzymatic modifications of histones; however attention has been diverted to histone modifications induced by by-products of metabolism without enzymatic engagement in the last decade. Non enzymatic modifications of histones are believed to be crucial for epigenetic landscape, cellular fate and for role in human diseases. Glycation of histone proteins constitutes the major non enzymatic modifications of nuclear proteins that have implications in diabetes and cancer. It has emerged that glycation damages nuclear proteins, modifies amino acids of histones at crucial locations, generates adducts affecting histone chromatin interaction, develops neo-epitopes inducing specific immune response and impacts cell function. Presence of circulating antibodies against glycated histone proteins in diabetes and cancer has shown immunological implications with diagnostic relevance. These crucial details make histone glycation an attractive focus for investigators. This review article, therefore, makes an attempt to exclusively summarize the recent researches in histone glycation, its impact on structural integrity of chromatin and elaborates on their role in diabetes and cancer. The work offers insights for future scientists who investigate the link between metabolism, bio-molecular structures, glycobiology, histone-DNA interactions in relation to diseases in humans.

Diabetes and Pancreatic Cancer-A Dangerous Liaison Relying on Carbonyl Stress

Simple Summary

Diabetic people have an increased risk of developing several types of cancers, particularly pancreatic cancer. The higher availability of glucose and/or lipids that characterizes diabetes and obesity is responsible for the increased production of highly reactive carbonyl compounds, a condition referred to as “carbonyl stress”. Also known as glycotoxins and lipotoxins, these compounds react quickly and damage various molecules in cells forming final products termed AGEs (advanced glycation end-products). AGEs were shown to markedly accelerate tumor development in an experimental model of pancreatic cancer and AGE inhibition prevented the tumor-promoting effect of diabetes. In humans, carbonyl stress has been associated with the risk of pancreatic cancer and recognized as a possible contributor to other cancers, including breast and colorectal cancer. These findings suggest that carbonyl stress is involved in cancer development and growth and may be the mechanistic link between diabetes and pancreatic cancer, thus representing a potential drug target.

Abstract

Both type 2 (T2DM) and type 1 (T1DM) diabetes mellitus confer an increased risk of pancreatic cancer in humans. The magnitude and temporal trajectory of the risk conferred by the two forms of diabetes are similar, suggesting a common mechanism. Carbonyl stress is a hallmark of hyperglycemia and dyslipidemia, which accompanies T2DM, prediabetes, and obesity. Accumulating evidence demonstrates that diabetes promotes pancreatic ductal adenocarcinoma (PDAC) in experimental models of T2DM, a finding recently confirmed in a T1DM model. The carbonyl stress markers advanced glycation end-products (AGEs), the levels of which are increased in diabetes, were shown to markedly accelerate tumor development in a mouse model of Kras-driven PDAC. Consistently, inhibition of AGE formation by trapping their carbonyl precursors (i.e., reactive carbonyl species, RCS) prevented the PDAC-promoting effect of diabetes. Considering the growing attention on carbonyl stress in the onset and progression of several cancers, including breast, lung and colorectal cancer, this review discusses the mechanisms by which glucose and lipid imbalances induce a status of carbonyl stress, the oncogenic pathways activated by AGEs and their precursors RCS, and the potential use of carbonyl-scavenging agents and AGE inhibitors in PDAC prevention and treatment, particularly in high-risk diabetic individuals.

Soluble Receptor for Advanced Glycation End-products (sRAGE) and Colorectal Cancer Risk: A Case-Control Study Nested within a European Prospective Cohort

BACKGROUND

Overexpression of the receptor for advanced glycation end-product (RAGE) has been associated with chronic inflammation, which in turn has been associated with increased colorectal cancer risk. Soluble RAGE (sRAGE) competes with RAGE to bind its ligands, thus potentially preventing RAGE-induced inflammation.

METHODS

To investigate whether sRAGE and related genetic variants are associated with colorectal cancer risk, we conducted a nested case-control study in the European Prospective Investigation into Cancer and Nutrition (EPIC). Plasma sRAGE concentrations were measured by ELISA in 1,361 colorectal cancer matched case-control sets. Twenty-four SNPs encoded in the genes associated with sRAGE concentrations were available for 1,985 colorectal cancer cases and 2,220 controls. Multivariable adjusted ORs and 95% confidence intervals (CIs) were computed using conditional and unconditional logistic regression for colorectal cancer risk and circulating sRAGE and SNPs, respectively.

RESULTS

Higher sRAGE concentrations were inversely associated with colorectal cancer (ORQ5vs.Q1, 0.77; 95% CI, 0.59-1.00). Sex-specific analyses revealed that the observed inverse risk association was restricted to men (ORQ5vs.Q1, 0.63; 95% CI, 0.42-0.94), whereas no association was observed in women (ORQ5vs.Q1, 1.00; 95% CI, 0.68-1.48; P heterogeneity for sex = 0.006). Participants carrying minor allele of rs653765 (promoter region of ADAM10) had lower colorectal cancer risk (C vs. T, OR, 0.90; 95% CI, 0.82-0.99).

CONCLUSIONS

Prediagnostic sRAGE concentrations were inversely associated with colorectal cancer risk in men, but not in women. An SNP located within ADAM10 gene, pertaining to RAGE shedding, was associated with colorectal cancer risk.

IMPACT

Further studies are needed to confirm our observed sex difference in the association and better explore the potential involvement of genetic variants of sRAGE in colorectal cancer development.

The potential role of dietary advanced glycation endproducts in the development of chronic non-infectious diseases: a narrative review

Increasing clinical and experimental evidence accumulated during the past few decades supports an important role for dietary advanced glycation endproducts (AGE) in the pathogenesis of many chronic non-infectious diseases, such as type 2 diabetes, CVD and others, that are reaching epidemic proportions in the Western world. Although AGE are compounds widely recognised as generated in excess in the body in diabetic patients, the potential importance of exogenous AGE, mostly of dietary origin, has been largely ignored in the general nutrition audience. In the present review we aim to describe dietary AGE, their mechanisms of formation and absorption into the body as well as their main mechanisms of action. We will present in detail current evidence of their potential role in the development of several chronic non-infectious clinical conditions, some general suggestions on how to restrict them in the diet and evidence regarding the potential benefits of lowering their consumption.