Clinical significance of serum interleukin-18 (IL-18) levels in patients with gastric cancer. Biomed Pharmacother. 2015;70:19-23. [PMID: 25776473 DOI: 10.1016/j.biopha.2014.12.040]

Circulating Proteins as Diagnostic Markers in Gastric Cancer

Gastric cancer (GC) is a highly malignant disease affecting humans worldwide and has a poor prognosis. Most GC cases are detected at advanced stages due to the cancer lacking early detectable symptoms. Therefore, there is great interest in improving early diagnosis by implementing targeted prevention strategies. Markers are necessary for early detection and to guide clinicians to the best personalized treatment. The current semi-invasive endoscopic methods to detect GC are invasive, costly, and time-consuming. Recent advances in proteomics technologies have enabled the screening of many samples and the detection of novel biomarkers and disease-related signature signaling networks. These biomarkers include circulating proteins from different fluids (e.g., plasma, serum, urine, and saliva) and extracellular vesicles. We review relevant published studies on circulating protein biomarkers in GC and detail their application as potential biomarkers for GC diagnosis. Identifying highly sensitive and highly specific diagnostic markers for GC may improve patient survival rates and contribute to advancing precision/personalized medicine.

Mechanism of inflammasomes in cancer and targeted therapies

Inflammasomes, composed of the nucleotide-binding oligomerization domain(NOD)-like receptors (NLRs), are immune-functional protein multimers that are closely linked to the host defense mechanism. When NLRs sense pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), they assemble into inflammasomes. Inflammasomes can activate various inflammatory signaling pathways, including nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, and produce a large number of proinflammatory cytokines, which are closely associated with multiple cancers. They can also accelerate the occurrence and development of cancer by providing suitable tumor microenvironments, promoting tumor cell proliferation, and inhibiting tumor cell apoptosis. Therefore, the exploitation of novel targeted drugs against various inflammasomes and proinflammatory cytokines is a new idea for the treatment of cancer. In recent years, more than 50 natural extracts and synthetic small molecule targeted drugs have been reported to be in the research stage or have been applied to the clinic. Herein, we will overview the mechanisms of inflammasomes in common cancers and discuss the therapeutic prospects of natural extracts and synthetic targeted agents.

S, Prasad H. L. K. Utility of serum interleukin-18 (IL-18) as a tumour marker in gastric cancer

Introduction: Gastric cancer (GC) is the fourth most prevailing cancer globally, attributing to more than 70% of cases in developing countries. Protein cancer biomarkers, such as CEA, CA- 125, AFP and PSA, are clinically helpful diagnostic tools, but they have low sensitivity and specificity for GC. Hence, it is essential to discover better markers for GC diagnosis. Interleukin-18 (IL-18) is the member of Interleukin-1 family. It is hypothesized to be a potent inhibitor of gastric acid secretion, leading to gastric atrophy and causing an increased risk of GC. This study was to evaluate the association between the serum IL-18 in GC.   Methodology: We included cases who underwent UGI Scopy and were proven to have GC histopathologically. The patients who presented to the out-patient who underwent UGI scopy and was found to have no growth were selected as controls. Twenty-eight cases and 84 control sample sizes were derived from nMaster V2. Blood samples from patients and controls were collected, and serum IL-18 levels were estimated using a solid-phase sandwich ELISA method.   Results: We found that the cut-off value of serum IL-18 was 85.59 pg/ml, had a sensitivity of 63.1% and specificity of 57.1%, with a positive predictive value of 81.5% and a negative predictive value of 34% in diagnosing GC. The study plotted the receiver operating characteristic curve against IL-18 for sensitivity and specificity. Statistically, we found through the Area Under the Curve (AUC) that the rise in serum IL-18 levels was a poor indicator of GC with a p-value of 0.078.   Conclusion: Statistically, a cut-off of 85.59pg/ml showed good sensitivity and specificity; however, the probability was insignificant, suggesting that IL-18 may not be of diagnostic importance. Studies with a larger sample size are required to further probe into the usefulness of estimating IL-18 in GC.

BuFeiXiaoJiYin ameliorates the NLRP3 inflammation response and gut microbiota in mice with lung cancer companied with Qi-yin deficiency

Introduction

NLRP3 inflammasome responses and gut microbiota have been shown an important role in lung cancer, however, the relationship between gut microbiota and NLRP3 inflammasome responses in lung cancer with Qi-yin deficiency remains elusive.

Methods

To investigate the effect of the traditional Chinese medicine BuFeiXiaoJiYin (BFXJY) on NLRP3 inflammasome responses and dysbiosis in lung cancer with Qi-yin deficiency, the female BALB/cA-nu mice were treated with LPS and ATP to induce inflammation, and were intragastrically treated with warm Chinese medicine and smoked with shavings to induce Qi-yin deficiency, as well as were injected with 1 × 10⁷/ml A549 cells to simulate lung cancer. Then the three different doses of BuFeiXiaoJiYin (BFXJY) and positive control (CRID3) were used for intervention in mice for 27 consecutive days. Then, we estimated the protection effect of BFXJY on lung cancer mice with Qi-yin deficiency, through deterring tumor growth, NLRP3 inflammasome, PKC signaling, and homeostasis of gut microbiota.

Results

In this study, we found that BFXJY could inhibit the tumor growth in lung cancer with Qi-yin deficiency by reducing the production of IL-1β and IL-18 and inhibiting NLRP3 inflammasome activation, which might be associated with the inhibition of PKC signaling. Furthermore, BFXJY could promote microbial diversity and balance the microbial composition changes induced by inflammation and Qi-yin deficiency in lung cancer.

Conclusion

BuFeiXiaoJiYin ameliorates the NLRP3 inflammation response and gut microbiota in mice with lung cancer companied with Qi-yin deficiency. Our study provides a theoretical basis for the clinical development of therapeutic drugs targeting to treat lung cancer.

Effect of lysed and non-lysed sickle red cells on the activation of NLRP3 inflammasome and LTB4 production by mononuclear cells

OBJECTIVE AND DESIGN

This study tested the hypothesis that sickle red blood cell (SS-RBC) can induce inflammasome NLRP3 components gene expression in peripheral blood mononuclear cells (PBMCs) as well as interleukin-1β (IL-1β) and leukotriene B4 (LTB4) production. Additionally, we investigated the effect of hydroxyurea (HU) treatment in these inflammatory markers.

METHODS

PBMCs from healthy donors (AA-PBMC) were challenged with intact and lysed RBCs from SCA patients (SS-RBC) and from healthy volunteers (AA-RBC). NLRP3, IL-1β, IL-18 and Caspase-1 gene expression levels were assessed by quantitative PCR (qPCR). IL-1β protein levels and LTB4 were measured by ELISA.

RESULTS

We observed that lysed SS-RBC induced the expression of inflammasome NLRP3 components, but this increase was more prominent for CASP1 and IL18 expression levels. Moreover, we observed that intact SS-RBC induced higher production of IL-1β and LTB4 than lysed SS-RBC. Although SCA patients treated with HU have a reduction in NLRP3 gene expression and LTB4 production, this treatment did not modulate the expression of other inflammasome components or IL-1β production.

CONCLUSIONS

Thus, our data suggest that caspase-1, IL-1β and IL-18 may contribute to the inflammatory status observed in SCA and that HU treatment may not interfere in this inflammatory pathway.

Analyzing the influence of IL18 in regulation of YAP1 in breast oncogenesis using cBioportal

Background

Yes‐associated protein 1 (YAP1) is responsible for tumor growth, progression and metastasis. The mechanisms controlling the generation and relative ratio of the functional YAP1 and other co‐factors are not well‐understood. Various literature reported that co‐factors like cytokines significantly influence signaling pathways to introduce epithelial immunity and regeneration, which later helps increase cancer‐related phenotypes. Among various cytokines, IL‐18 has emerged as a major player in inflammation and progression of different types of cancers. Till now, much information has not been known about the role of YAP1 in tumor aggressiveness and immune evasion in breast cancer with respect to IL‐18.

Aim

We aimed to explore the effect of YAP1 in tumor aggressiveness and immune evasion in breast invasive carcinoma and metastatic breast cancer in the context of Interleukin‐18 (IL‐18) in silico.

Methods and Results

We used publicly available data generated by The Cancer Genome Atlas (TCGA) Research Network through cBioportal web platform. Kaplan–Meier method was used to determine the overall survival and comparison between curves were made using Log‐Rank test. The p values were determined by Fisher's exact test with the null hypothesis. Correlation plots were analyzed by comparison with gene copy numbers from the GISTIC2.0, available through cBioportal.

Our analyses suggest that IL‐18 influences YAP1 expression in breast oncogenesis via Interferon‐gamma (IFN‐γ) production. Patients having a higher expression of IL‐18 possess a better prognosis and higher YAP1 expression with lower IL18 drives to poor clinical results in breast cancer.

Conclusion

This can provide new approaches to better understand the relation between YAP1 and IL‐18 in breast cancer progression by performing in vitro and in vivo studies. Also, IL‐18 can be considered as a potential target for tumor treatment in YAP1 overexpressed breast carcinoma.

Intestinal bacteria are potential biomarkers and therapeutic targets for gastric cancer

The diagnostic and therapeutic role of intestinal microbiota in gastric carcinogenesis remains unclear. In this study, feces from gastric cancer patients and healthy people were sequenced for microbiota analysis, and the correlation between fecal bacteria and the occurrence of gastric cancer was explored. The β-diversity results showed that microbial compositions varied between gastric cancer patients and healthy people. Interestingly, the dissection of microbial structure revealed that all facultative anaerobic genera with relatively high abundances expanded significantly in gastric cancer patients. The succeeding correlation analysis demonstrated a distorted interaction of intestinal bacteria in gastric cancer. The application of some differential bacteria, Desulfovibrio, Escherichia, Faecalibacterium or Oscillospira, as biomarkers to predict gastric cancer could all reach an accuracy of 0.900 or above. The shift in Desulfovibrio was specifically verified by qPCR in newly collected fecal samples, and the patients with stage IV gastric cancer were identified to have significantly more Desulfovibrio than those with stage I, II and III gastric cancer. The possible role of Desulfovibrio in gastric cancer was assessed with H₂S-treated HT-29 cells, and the results showed that H₂S induced NO, IL-1β and IL-18 production, which is important for inflammation promotion and can be delivered through the bloodstream. This study suggests a correlation of intestinal microbiota and the development of gastric cancer.

Chromatin Accessibility Regulates Gene Expression and Correlates With Tumor-Infiltrating Immune Cells in Gastric Adenocarcinoma

Background

We explored key molecules affecting the prognosis of gastric adenocarcinoma (STAD) using co-analysis of chromatin accessibility (ATAC-seq), mRNA expression (RNA-seq), and overall survival.

Methods

We used the assay for transposase-accessible chromatin using sequencing (ATAC-seq) profiles to identify genes with chromatin accessibilities in their promoter regions. The RNA-seq profiles were processed for differentially expressed genes (DEGs) at mRNA level. The DEGs with chromatin accessibilities in promoter regions were further filtered using the Pearson correlation with TP53 expression. After co-analysis, genes were identified for the prognostic value using Kaplan–Meier method, followed by Pearson correlation analysis with significant pathways. For verification, we acquired clinical samples for qPCR and immunohistochemistry (IHC). Multidimensional database validations were performed to prevent the bias introduced by the use of a single database.

Results

We identified 11,557 DEGs and 57 genes with chromatin accessibilities. The co-analysis of ATAC-seq, RNA-seq, and clinical survival data revealed that interleukin-18 binding protein (IL18BP), with significant chromatin accessibility in its promoter region and differential mRNA expression, might be directly regulated by TP53 and influence STAD prognosis. Further, gene set variation analysis indicated that IL18BP may impact the survival of STAD patients in an immune-related manner. According to the CIBERSORT algorithm and Pearson correlation, the integration of IL18BP and CD4+ T memory cells may play an important role in the prognosis of STAD patients.

Conclusion

IL18BP, regulated by TP53, may serve as a key molecule affecting STAD prognosis. And the mechanism is proposed to be the interaction between IL18BP and CD4+ T cells.

Immune Cells Combined With NLRP3 Inflammasome Inhibitor Exert Better Antitumor Effect on Pancreatic Ductal Adenocarcinoma

Pancreatic cancer is among the most aggressive malignancies associated with chronic inflammation. Moreover, cellular immunity can be inhibited by inflammation induced by nucleotide-binding domain, leucine-rich family, pyrin-containing 3 (NLRP3) inflammasome. Accordingly, NLRP3 inhibition combining cytokine-induced killer (CIK) cells may improve antitumor efficacy. 3,4-Methylenedioxy-β-nitrostyrene (MNS) was selected as a specific NLRP3 inflammasome inhibitor. Western blot was used to evaluate the NLRP3 inflammasome expression in pancreatic cancer cell lines SW1990 and PANC-1. The impact of NLRP3 inhibition on migration, invasiveness, and proliferation of pancreatic cancer cells was analyzed through wound healing assay, Transwell assay, and Cell Counting Kit-8 (CCK-8) assay, respectively. The combining antitumor effect in vivo of CIK and NLRP3 inhibition was evaluated in a subcutaneous human pancreatic cancer BALB/c nude mouse model. Western blot analysis showed significant expression of NLRP3 inflammasome in human pancreatic cancer lines SW1990 and PANC-1, and MNS did significantly inhibit the expression of NLRP3 inflammasome in cell lines. Moreover, NLRP3 inhibition could significantly decrease the migration, invasiveness, and proliferation of pancreatic cancer cells. In vivo experiments showed that combination treatment with MNS and CIK cells had the greatest antitumor effect among the four treatment groups including control, MNS, and CIK. Combination treatment with NLRP3 inflammasome inhibition and CIK cells showed greater antitumor efficacy through inflammation inhibition and immunity restoration.

Prognostic Role of IL-18 in Various Human Cancers and Radiation Injuries: A Meta-Analysis

Background:

In recent years, more and more studies have shown that various inflammatory factors have predictive effects on the prognosis of various human tumors. However, the prognostic role of interleukin 18 (IL-18) remains controversial. Furthermore, its role in radiation-induced injuries relating to radiotherapy (RT) is also unclear. In this study, we conducted the meta-analysis to clarify its roles in prognosis of human tumors and radiation-induced injuries relating to RT.

Methods:

We comprehensively searched PubMed, Embase, and Cochrane Library to identify studies published before November 2019 involving patients with cancer expressing IL-18 and which reported overall survival (OS) during the follow-up period.

Results:

A total of 1376 samples from 16 studies showed that high expression of IL-18 is closely related to prognosis and OS for patients with carcinoma (hazard ratio [HR]: 2.12; 95% CI: 1.81-2.49; P = .04; random-effect model). In addition, subgroup analysis proved that high expression of IL-18 was related to poor OS of hematologic tumor (HR: 2.03, 95% CI: 1.44-2.86, P < .00001), hepatocellular carcinoma (HR: 1.99, 95% CI: 1.38-2.86, P = .0002), and gastric cancer (HR: 2.00, 95% CI: 1.12-3.57, P = .02).

Conclusions:

High expression of IL-18 is related with poor prognosis of carcinoma.

Is NLRP3 or NLRP6 inflammasome activation associated with inflammation-related lung tumorigenesis induced by benzo(a)pyrene and lipopolysaccharide?

Chronic inflammation has been shown to play a vital role in lung tumorigenesis. Recently, we have successfully developed a C57BL/6 mouse model of inflammation-related lung tumorigenesis induced by benzo(a)pyrene [B(a)p] and lipopolysaccharide (LPS), which will contribute to better understand the association between pulmonary inflammation and cancer. In this study, we aim to explore the role of NLRP3 and NLRP6 inflammasome in lung tumorigenesis in the animal model that we set up previously. Levels of NLRP3, NLRP6, interleukin-1β (IL-1β) and IL-18 protein in lung tissues were detected by using immunohistochemistry. The co-localization of NLRP3 or NLRP6 with caspase-1 was examined using immunofluorescence and confocal. Western blotting was used to evaluate the levels of caspase-1 p10 and cleaved-IL-1β protein. The expression of IL-18 in bronchoalveolar lavage fluid (BALF) was measured using ELISA kit. The expression of NLRP3, NLRP6 and IL-18 protein in the lung tissues of mice exposed to B(a)p plus LPS was upregulated significantly compared with those in Vehicle control group. Immunofluorescent results indicated the co-localization of NLRP3 with caspase-1 was increased in the lung tissues of LPS-, B(a)p- or B(a)p plus LPS-exposed mice than that in Vehicle control group, but no co-localization of NLRP6 with caspase-1. Additionally, caspase-1 activation was induced, cleaved-IL-1β in lung tissues and IL-18 protein in BALF were increased in B(a)p plus LPS-exposed mice compared with those in B(a)p group. In conclusion, our results from this study demonstrate that NLRP3 inflammasome, not NLRP6 inflammasome, activation is involved in B(a)p plus LPS-induced inflammation-related lung tumorigenesis in mice, but the mechanisms of NLRP6 participate in the development of lung cancer should be further investigated.

Listeria monocytogenes cancer vaccines: bridging innate and adaptive immunity

Purpose of the Review

Immunotherapy has emerged as a promising cancer treatment, however success in only select clinical indications underscores the need for novel approaches. Recently Listeria monocytogenes-based vaccines have been developed to drive tumor specific T-cell responses. Here, we discuss recent preclinical studies using L. monocytogenes vaccines, innate immune pathways that influence T-cell priming, and new vaccine strategies in clinical trials.

Recent Findings

Recent studies indicate that in addition to inducing antigen specific T-cell responses, L. monocytogenes vaccines remodel the TME. In addition, several innate immune pathways influence adaptive immune responses to L. monocytogenes and modulating these pathways holds promise to enhance anti-tumor T-cell responses.

Summary

The interplay between innate and adaptive immune responses to L. monocytogenes is poorly understood. Understanding these interactions will facilitate the design of better anti-cancer vaccines and improved use of combination therapies.

Interleukin-18 Is a Prognostic Biomarker Correlated with CD8+ T Cell and Natural Killer Cell Infiltration in Skin Cutaneous Melanoma

Interleukin-18 (IL-18) is a cytokine that enhances innate and adaptive immune responses. Although there are conflicting reports about the roles of IL-18 in melanoma progression, the clinical relevance of IL-18 expression has not been comprehensively studied. In this study, we investigated IL-18 expression and its correlation with patient survival and immune cell infiltration in melanoma using cancer gene expression data publicly available through various databases. IL18 mRNA expression was found to be significantly lower in melanoma tissues than normal tissues. Kaplan–Meier survival analysis showed that IL18 expression was positively correlated with patient survival. To investigate the possible mechanisms by which IL18 expression increased patient survival, we then assessed the correlation between IL18 expression and immune cell infiltration levels. Infiltration of various immune cells, especially CD8⁺ T and natural killer (NK) cells, which are cytolytic effector cells, was significantly increased by IL18 expression. Additionally, the expression levels of two cytolytic molecules including perforin and granzyme B were significantly positively correlated with IL18 expression. Collectively, this study provides the first evidence that IL18 expression has prognostic value for melanoma patient survival and is strongly correlated with CD8⁺ T and NK cell infiltration, suggesting the role of IL-18 as a biomarker for predicting melanoma prognosis.

Impaired skin barrier function caused by reactive oxygen species in mice with colonic tumours

Purpose: We have previously reported that skin barrier function is disrupted in mice with colonic tumours induced by azoxymethane (AOM) and dextran sodium sulphate (DSS). We postulated that the impaired skin barrier function was associated with reactive oxygen species derived from gp91phox. In this study, we investigated the mechanisms underlying the impaired skin barrier function using gp91phox-/- mice. Materials and methods: We induced colonic tumorigenesis in C57BL/6j mice by AOM + DSS administration and evaluated the influence of reactive oxygen species on skin barrier function by using the hydroxyl radical scavenger N-acetyl-l-cysteine (NAC) or gp91phox-/- mice. Damage to the colon and skin following treatment with AOM + DSS was monitored using protein analysis methods and by detection of inflammatory mediators in the plasma. Results: NAC could not prevent the increase in transepidermal water loss (TEWL) and decrease in skin hydration level caused by AOM + DSS in gp91phox+/+ mice. However, gp91phox-/- mice showed no change in TEWL and skin hydration level. The dermal expression levels of nucleotide-binding domain, leucine-rich containing family, pyrin-domain containing 3 (NLRP3), and caspase-1 were reduced in gp91phox-/- mice. Moreover, the plasma concentrations of interleukin-18 and thymic stromal lymphopoietin (TSLP) were lower in gp91phox-/- mice than those in gp91phox+/+ mice. Inhibition of hydrogen peroxide production from superoxide anions in the gp91phox-/- status prevented the increased TEWL and decreased skin hydration level noted with degradation of NLRP3 and caspase-1. Conclusions: Superoxide anions may play an important role in the onset of the impaired skin barrier function in mice with colonic tumours.

Interleukin-18 expression in oral squamous cell carcinoma: its role in tumor cell migration and invasion, and growth of tumor cell xenografts

Oral squamous cell carcinoma (OSCC) is one of the most common head and neck malignancies. Advanced stages of the disease are associated with poor survival, highlighting a need for new treatment modalities. We previously showed that the proinflammatory cytokine interleukin‐18 (IL‐18) has a tumor suppressive role in OSCC. Here, we investigated the effects of IL‐18 on proliferation, migration, and invasion of OSCC cells ex vivo and in vitro, and in nude mouse xenografts. We report that expression of tankyrase 2 (TNKS2), β‐catenin, and N‐cadherin was higher in tumor cells than in normal mucosae, whereas the expression of IL‐18 and E‐cadherin was higher in normal than in tumor tissues. Elevated expression of IL‐18 (P < 0.01) and E‐cadherin (P = 0.034) was associated with tumor differentiation, whereas expression of TNKS2 (P < 0.01), β‐catenin (P = 0.012), and N‐cadherin (P < 0.01) was associated with tumor de‐differentiation. Furthermore, compared with the vector control, IL‐18 overexpression promoted tumor cell migration and invasion (P < 0.01), but inhibited growth of tumor cell xenografts (P < 0.05). At the protein level, expression levels of IL‐18 (P < 0.01), TNKS2 (P = 0.045), β‐catenin (P = 0.028), and N‐cadherin (P = 0.068) were upregulated in tumor cells after IL‐18 overexpression compared with those of the vector control mice, whereas expression levels of E‐cadherin (P = 0.045) were decreased. In conclusion, our data suggest that IL‐18 overexpression induces oral SCC cell invasion and metastasis by promoting the tumor cell epithelial–mesenchymal transition via the Wnt/β‐catenin signaling pathway.

CAR T Cells Releasing IL-18 Convert to T-Bethigh FoxO1low Effectors that Exhibit Augmented Activity against Advanced Solid Tumors

Adoptive therapy with chimeric antigen receptor (CAR)-redirected T cells has achieved remarkable efficacy in the treatment of hematopoietic malignancies. However, eradicating large solid tumors in advanced stages of the disease remains challenging. We explored augmentation of the anti-tumor immune reaction by establishing an acute inflammatory reaction. Systematic screening indicates that IL-18 polarizes CAR T cells toward T-bet^high FoxO1^low effectors with an acute inflammatory response. CAR T cells engineered with inducible IL-18 release exhibited superior activity against large pancreatic and lung tumors that were refractory to CAR T cells without cytokines. IL-18 CAR T cell treatment was accompanied by an overall change in the immune cell landscape associated with the tumor. More specifically, CD206^- M1 macrophages and NKG2D⁺ NK cells increased in number, whereas Tregs, suppressive CD103⁺ DCs, and M2 macrophages decreased, suggesting that "iIL18 TRUCKs" can be used to sensitize large solid tumor lesions for successful immune destruction.

The inflammasome: an emerging therapeutic oncotarget for cancer prevention

Deregulated inflammation is considered to be one of the hallmarks of cancer initiation and development regulation. Emerging evidence indicates that the inflammasome plays a central role in regulating immune cells and cytokines related to cancer. The inflammasome is a multimeric complex consisting of NOD-like receptors (NLRs) and responds to a variety of endogenous (damage-associated molecular patterns) and exogenous (pathogen-associated molecular patterns) stimuli. Several lines of evidence suggests that in cancer the inflammasome is positively associated with characteristics such as elevated levels of IL-1β and IL-18, activation of NF-κB signaling, enhanced mitochondrial oxidative stress, and activation of autophagic process. A number of NLRs, such as NLRP3 and NLRC4 are also highlighted in carcinogenesis and closely correlate to chemoresponse and prognosis. Although conflicting evidence suggested the duplex role of inflammasome in cancer development, the phenomenon might be attributed to NLRs difference, cell and tissue type, cancer stage, and specific experimental conditions. Given the promising role of inflammasome in mediating cancer development, precise elucidation of its signaling network and pathological significance may lead to novel therapeutic options for malignancy therapy and prevention.

Inflammasome and Cancer

The current chapter focuses on the role of inflammasome in cancer prevention and development. Emerging evidence suggested that inflammasome is closely correlated with elevated levels of IL-1β and IL-18, activation of NF-κB signaling, enhanced mitochondrial oxidative stress, and activation of autophagic process in cancer. Meanwhile, inflammasome component NOD-like receptors (NLRs) are also involved in carcinogenesis and closely correlated to chemoresponse and prognosis. Although several lines indicated the duplex role of inflammasome in cancer development, the phenomenon might be attributed to NLR difference, cell and tissue type, cancer stage, and specific experimental conditions. Designation of inflammasome targeting strategy has become a novel tool for cancer prevention or treatment.

Genotyping and differential expression analysis of inflammasome genes in sporadic malignant melanoma reveal novel contribution of CARD8, IL1B and IL18 in melanoma susceptibility and progression

Sporadic melanoma malignancy is correlated with constitutive secretion of IL-1β in transformed melanocytes suggesting the involvement of inflammasome in melanoma. Common variants in inflammasome genes are known to affect IL-1β expression. To investigate the contribution of inflammasome genetics in melanoma development and progression and to identify a potential prognostic marker, the distribution of selected inflammasome SNPs was analysed in a Brazilian case/control cohort of sporadic malignant melanoma (SMM) and then the expression of inflammasome components was evaluated in melanoma biopsies. Allele and gene-specific Taqman assays were implied for genotyping of case/control DNA samples and for relative expression analysis in skin biopsies respectively. CARD8 rs6509365 was found to be significantly more common in healthy volunteers than in SMM patients suggesting a protection effect of this variant towards melanoma development. Accordingly, CARD8 expression was found to be reduced in nevus compared to melanoma biopsies. Upon stratification, NLRP1 rs11651270 and CARD8 rs2043211 were found associated with nodular melanoma; IL1B rs1143643 to a lower value of Breslow index; IL18 rs5744256 to melanoma development in sun sensitive individuals. As expected, IL1B expression was up-regulated in tumour biopsies especially in metastatic samples, whereas IL18 was down-regulated compared to nevus. Our results demonstrated for the first time the contribution of inflammasome genes CARD8, IL1B and IL18 in SMM.

Sickle red cells as danger signals on proinflammatory gene expression, leukotriene B4 and interleukin-1 beta production in peripheral blood mononuclear cell

This study tested the hypothesis that sickle red blood cell (SS-RBC) induce Toll-like receptors (TLR) and Nod-like receptor family, pyrin domain containing 3 (NLRP3)- inflammasome expression in peripheral blood mononuclear cells (PBMC). TLR and NLRP3 inflammasome could contribute to the maintenance of the inflammatory status in sickle cell anemia (SCA) patients, since SS-RBC act as danger signals activating these pathways. In this study, first, we evaluated TLR (2, 4, 5 and 9), NLRP3, Caspase-1, interleukin (IL)-1β and IL-18 expression in PBMC freshly isolated from SCA patients (SS-PBMC) in comparison with PBMC from healthy individuals (AA-PBMC). In the second moment, we investigated whether SS-RBC could interfere with the expression of these molecules in PBMC from healthy donor, in the absence or presence of hydroxyurea (HU) in vitro. TLRs and NLRP3 inflammasome expression were investigated by qPCR. IL-1β, Leukotriene-B4 (LTB4) and nitrite production were measured in PBMC (from healthy donor) culture supernatants. TLR2, TLR4, TLR5, NLRP3 and IL-1β were highly expressed in SS-PBMC when compared to AA-PBMC. Additionally, SS-RBC induced TLR9, NLRP3, Caspase-1, IL-1β and IL-18 expression and induced IL-1β, LTB4 and nitrite production in PBMC cultures. HU did not prevent TLR and NLRP3 inflammasome expression, but increased TLR2 and IL-18 expression and reduced nitrite production. In conclusion, our data suggest that TLR and inflammasome complexes may be key inducers of inflammation in SCA patients, probably through SS-RBC; also, HU does not prevent NLRP3 inflammasome- and TLR-dependent inflammation, indicating the need to develop new therapeutic strategies to SCA patients that act with different mechanisms of those observed for HU.

Update on a tumor-associated NADH oxidase in gastric cancer cell growth

Gastric cancer is one of the most common human malignancies, and its prevalence has been shown to be well-correlated with cancer-related deaths worldwide. Regrettably, the poor prognosis of this disease is mainly due to its late diagnosis at advanced stages after the cancer has already metastasized. Recent research has emphasized the identification of cancer biomarkers in the hope of diagnosing cancer early and designing targeted therapies to reverse cancer progression. One member of a family of growth-related nicotinamide adenine dinucleotide (NADH or hydroquinone) oxidases is tumor-associated NADH oxidase (tNOX; ENOX2). Unlike its counterpart CNOX (ENOX1), identified in normal rat liver plasma membranes and shown to be stimulated by growth factors and hormones, tNOX activity purified from rat hepatoma cells is constitutively active. Its activity is detectable in the sera of cancer patients but not in those of healthy volunteers, suggesting its clinical relevance. Interestingly, tNOX expression was shown to be present in an array of cancer cell lines. More importantly, inhibition of tNOX was well correlated with reduced cancer cell growth and induction of apoptosis. RNA interference targeting tNOX expression in cancer cells effectively restored non-cancerous phenotypes, further supporting the vital role of tNOX in cancer cells. Here, we review the regulatory role of tNOX in gastric cancer cell growth.

Multiplexed detection of serological cancer markers with plasmon-enhanced Raman spectro-immunoassay

Circulating biomarkers have emerged as promising non-invasive, real-time surrogates for cancer diagnosis, prognostication and monitoring of therapeutic response. Emerging data, however, suggest that single markers are inadequate in describing complex pathologic transformations. Architecting assays capable of parallel measurements of multiple biomarkers can help achieve the desired clinical sensitivity and specificity while conserving patient specimen and reducing turn-around time. Here we describe a plasmon-enhanced Raman spectroscopic assay featuring nanostructured biomolecular probes and spectroscopic imaging for multiplexed detection of disseminated breast cancer markers cancer antigen (CA) 15-3, CA 27-29 and cancer embryonic antigen (CEA). In the developed SERS assay, both the assay chip and surface-enhanced Raman spectroscopy (SERS) tags are functionalized with monoclonal antibodies against CA15-3, CA27-29 and CEA, respectively. Sequential addition of biomarkers and functionalized SERS tags onto the functionalized assay chip enable the specific recognition of these biomarkers through the antibody-antigen interactions, leading to a sandwich spectro-immunoassay. In addition to offering extensive multiplexing capability, our method provides higher sensitivity than conventional immunoassays and demonstrates exquisite specificity owing to selective formation of conjugated complexes and fingerprint spectra of the Raman reporter. We envision that clinical translation of this assay may further enable asymptomatic surveillance of cancer survivors and speedy assessment of treatment benefit through a simple blood test.