Tumour cell lines HT-29 and FaDu produce proinflammatory cytokines and activate neutrophils in vitro: possible applications for neutrophil-based antitumour treatment. Mediators Inflamm. 2009;2009:817498. [PMID: 20169105 PMCID: PMC2821782 DOI: 10.1155/2009/817498]

Chitosan/poly(lactic-co-glycolic)acid Nanoparticle Formulations with Finely-Tuned Size Distributions for Enhanced Mucoadhesion

Non-parenteral drug delivery systems using biomaterials have advantages over traditional parenteral strategies. For ocular and intranasal delivery, nanoparticulate systems must bind to and permeate through mucosal epithelium and other biological barriers. The incorporation of mucoadhesive and permeation-enhancing biomaterials such as chitosan facilitate this, but tend to increase the size and polydispersity of the nanoparticles, making practical optimization and implementation of mucoadhesive nanoparticle formulations a challenge. In this study, we adjusted key poly(lactic-co-glycolic) acid (PLGA) nanoparticle formulation parameters including the organic solvent and co-solvent, the concentration of polymer in the organic phase, the composition of the aqueous phase, the sonication amplitude, and the inclusion of chitosan in the aqueous phase. By doing so, we prepared four statistically unique size groups of PLGA NPs and equally-sized chitosan-PLGA NP counterparts. We loaded simvastatin, a candidate for novel ocular and intranasal delivery systems, into the nanoparticles to investigate the effects of size and surface modification on drug loading and release, and we quantified size- and surface-dependent changes in mucoadhesion in vitro. These methods and findings will contribute to the advancement of mucoadhesive nanoformulations for ocular and nose-to-brain drug delivery.

Agent Repurposing for the Treatment of Advanced Stage Diffuse Large B-Cell Lymphoma Based on Gene Expression and Network Perturbation Analysis

Over 50% of diffuse large B-cell lymphoma (DLBCL) patients are diagnosed at an advanced stage. Although there are a few therapeutic strategies for DLBCL, most of them are more effective in limited-stage cancer patients. The prognosis of patients with advanced-stage DLBCL is usually poor with frequent recurrence and metastasis. In this study, we aimed to identify gene expression and network differences between limited- and advanced-stage DLBCL patients, with the goal of identifying potential agents that could be used to relieve the severity of DLBCL. Specifically, RNA sequencing data of DLBCL patients at different clinical stages were collected from the cancer genome atlas (TCGA). Differentially expressed genes were identified using DESeq2, and then, weighted gene correlation network analysis (WGCNA) and differential module analysis were performed to find variations between different stages. In addition, important genes were extracted by key driver analysis, and potential agents for DLBCL were identified according to gene-expression perturbations and the Crowd Extracted Expression of Differential Signatures (CREEDS) drug signature database. As a result, 20 up-regulated and 73 down-regulated genes were identified and 79 gene co-expression modules were found using WGCNA, among which, the thistle1 module was highly related to the clinical stage of DLBCL. KEGG pathway and GO enrichment analyses of genes in the thistle1 module indicated that DLBCL progression was mainly related to the NOD-like receptor signaling pathway, neutrophil activation, secretory granule membrane, and carboxylic acid binding. A total of 47 key drivers were identified through key driver analysis with 11 up-regulated key driver genes and 36 down-regulated key diver genes in advanced-stage DLBCL patients. Five genes (MMP1, RAB6C, ACCSL, RGS21 and MOCOS) appeared as hub genes, being closely related to the occurrence and development of DLBCL. Finally, both differentially expressed genes and key driver genes were subjected to CREEDS analysis, and 10 potential agents were predicted to have the potential for application in advanced-stage DLBCL patients. In conclusion, we propose a novel pipeline to utilize perturbed gene-expression signatures during DLBCL progression for identifying agents, and we successfully utilized this approach to generate a list of promising compounds.

Neutrophil Suppresses Tumor Cell Proliferation via Fas /Fas Ligand Pathway Mediated Cell Cycle Arrested

While neutrophils have dutifully performed their function in injury and infection, the recent works have found that cytotoxicity and/or cytostatic of neutrophils has also been observed in tumor. Till now the molecular players that participate in this neutrophils antitumoral effect remain unclear. In the current study, we find that neutrophils from healthy donors have potent suppression to tumor cell lines by physical contact. Importantly, these suppression activities seem to be cancer cell-specific which is not observed in the normal cells. Further observations show that neutrophils mediated tumor cell lines growth inhibitory effect through early cell cycle arrested. Treatment with an antagonist Fas receptor in A549 cell line or knocking out of the Fas gene in A549 cell line recovers tumor cells cycle and lessen neutrophils anti-tumor effect. The interaction between neutrophils and A549 cell line through Fas ligand /Fas regulates the expression of cell cycle checkpoint proteins, leading to early cell cycle arrest. This phenomenon is also seen in other 3 tumor cell lines. Taken together, our results identified a new role of Fas ligand /Fas interaction in neutrophils antitumoral effect in tumors via arresting cell cycle.

Study of tumor growth indicates the existence of an "immunological threshold" separating states of pro- and antitumoral peritumoral inflammation

Background

Peritumoral inflammation—a response mainly involving polimorphonuclear neutrophils—has traditionally been thought protumoral in its effects. In recent years, however, a number of studies have indicated that it may play an important antitumoral role. This discrepancy has been difficult to explain.

Methods and findings

This work describes a tool for simulating tumor growth that obeys the universal model of tumor growth dynamics, and shows through its use that low intensity peritumoral inflammation exerts a protumoral effect, while high intensity inflammation exerts a potent antitumoral effect. Indeed, the simulation results obtained indicate that a sufficiently strong antitumoral effect can reverse tumor growth, as has been suggested several times in the clinical literature.

Conclusions

The present result indicate that an ‘immunological threshold’ must exist, marking the boundary between states in which peritumoral inflammation is either harmful or beneficial. These findings lend support to the idea that stimulating intense peritumoral inflammation could be used as a treatment against solid tumors.

Expression of IL-1α correlates with distant metastasis in patients with head and neck squamous cell carcinoma

The presence of IL-1 in human cancers is associated with aggressive tumor biology but its prognostic value is unknown. We studied whether IL-1α expression is a prognostic marker of distant metastasis in patients with head and neck squamous cell carcinoma (HNSCC). IL-1α mRNA and protein levels were determined in tumor samples and cancer cell lines using RT-PCR and ELISA. The effects of constitutive IL-1α expression by tumor lines were characterized. IL-1α mRNA and protein secretion were higher in tumor samples from patients who later developed distant metastasis than in patients who did not. By using distant metastasis as a dependent variable, patients were classified into two categories of IL-1α transcript-levels. The high-IL-1α group had a significantly lower five-year distant metastasis-free survival than the low-IL-1α group [70.0% (CI 95%: 55.9-84.1%) vs 94.7% (CI 95%:90.2-99.2%)]. When IL-1α transcript-levels were combined with clinical factors related to tumor metastasis, the predictive power of the model increased significantly. Additionally, transcript levels of IL-1α correlated significantly with those of the IL-1 family genes and genes related to the metastatic process. IL-1 treatment of microvascular endothelial cells increased adhesion of HNSCC cells but no differences were found based on constitutive IL-1α expression by tumor cells. Nevertheless, IL-1α produced by tumor cells effectively increased their transmigration across the endothelium. We found a significant relationship between IL-1α expression and development of distant metastasis in HNSCC patients. IL-1α expression could help to define a subset of patients at high risk of distant metastasis who could benefit from adjuvant treatment.

Expression and Cellular Localization of 15-Hydroxy-Prostaglandin-Dehydrogenase in Abdominal Aortic Aneurysm

PGE₂ has been implicated in abdominal aortic aneurysm (AAA) associated hypervascularization. PGE₂-metabolism involves 15-hydroxyprostaglandin-dehydrogenase (15-PGDH) the expression of which in AAA is unknown. The aim of this study was to examine the expression and cell distribution of 15-PGDH in AAA. Here, we show that 15-PGDH mRNA levels were significantly higher in aorta samples from patients undergoing AAA repair than in those from healthy multiorgan donors. Consequently, the ratio of metabolized PGE₂ secreted by aortic samples was significantly higher in AAA. AAA production of total PGE₂ and PGE₂ metabolites correlated positively with PGI₂ production, while the percentage of metabolized PGE₂ correlated negatively with the total amount of PGE₂ and with PGI₂. Transcript levels of 15-PGDH were statistically associated with leukocyte markers but did not correlate with microvascular endothelial cell markers. Immunohistochemistry revealed 15-PGDH in the areas of leukocyte infiltration in AAA samples, mainly associated with CD45-positive cells, but not in normal aorta samples. We provide new data concerning 15-PGDH expression in human AAA, showing that 15-PGDH is upregulated in AAA and mainly expressed in infiltrating leukocytes. Our data suggest that microvasculature was not involved in PGE₂ catabolism, reinforcing the potential role of microvasculature derived PGE₂ in AAA-associated hypervascularization.

Acute bacterial infection negatively impacts cancer specific survival of colorectal cancer patients

AIM: To assess the impact of bacterial infections on cancer-specific survival in patients with colorectal cancer.

METHODS: This was a retrospective cohort study of colorectal cancer patients treated at the A.C. Camargo Cancer Center between January 2006 and April 2010. The presence of bacterial infection during cancer treatment, or up to one year after, was confirmed by laboratory tests or by the physician. Infections of the urinary, respiratory or digestive tracts, bloodstream, skin or surgical site were defined by testing within a single laboratory. Criteria for exclusion from the study were: chronically immunosuppressed patients; transplant patients (due to chronic immunosuppression); human immunodeficiency virus carriers; chronic use of corticosteroids or other immunosuppressive drugs; patients with autoimmune disease or primary immunodeficiency; known viral or parasitic infections. Patients with infections that did not require hospitalization were not included in the study because of the difficulty of collecting and tracking data related to infectious processes. In addition, patients hospitalized for pulmonary thromboembolism, stroke, acute myocardial infarction, uncontrolled diabetes, malignant hypercalcemia or other serious non-infectious complications not directly related to infection were also excluded. Survival curves were plotted using the Kaplan-Meier method, and log-rank tests (univariate analysis) and a Cox test assuming a proportional hazards model (multivariate analysis) were performed to examine associations between clinical history and characteristics of infection with cancer-specific survival.

RESULTS: One-hundred and six patients with colorectal cancer were divided into two groups based on the presence or absence of bacterial infection. Patient ages ranged from 23 to 91 years, with a median of 55 years. The majority of patients were male (57/106, 53.77%) with stage III colorectal cancer (45/106, 44.11%). A total of 86 bacteriologic events were recorded. Results indicate that the presence and number of infections during or after the end of treatment were associated with poorer-cancer specific survivals (P = 0.02). Elevated neutrophil counts were also associated with poorer cancer-specific survival (P = 0.02). Analysis of patient age revealed that patients > 65 years of age had a poorer cancer-specific survival (P = 0.04). A multivariate analysis demonstrated that infection was an independent predictor of poor survival (HR = 2.62, 95%CI: 1.26-5.45; P = 0.01) along with advanced clinical staging (HR = 2.63, 95%CI: 1.08-6.39; P = 0.03).

CONCLUSION: Infection and high neutrophil counts are associated with a poorer cancer-specific survival in colorectal cancer patients.

The Multifaceted Roles Neutrophils Play in the Tumor Microenvironment

Neutrophils are myeloid cells that constitute 50-70 % of all white blood cells in the human circulation. Traditionally, neutrophils are viewed as the first line of defense against infections and as a major component of the inflammatory process. In addition, accumulating evidence suggest that neutrophils may also play a key role in multiple aspects of cancer biology. The possible involvement of neutrophils in cancer prevention and promotion was already suggested more than half a century ago, however, despite being the major component of the immune system, their contribution has often been overshadowed by other immune components such as lymphocytes and macrophages. Neutrophils seem to have conflicting functions in cancer and can be classified into anti-tumor (N1) and pro-tumor (N2) sub-populations. The aim of this review is to discuss the varying nature of neutrophil function in the cancer microenvironment with a specific emphasis on the mechanisms that regulate neutrophil mobilization, recruitment and activation.

Microvascular COX-2/mPGES-1/EP-4 axis in human abdominal aortic aneurysm

We investigated the prostaglandin (PG)E2 pathway in human abdominal aortic aneurysm (AAA) and its relationship with hypervascularization. We analyzed samples from patients undergoing AAA repair in comparison with those from healthy multiorgan donors. Patients were stratified according to maximum aortic diameter: low diameter (LD) (<55 mm), moderate diameter (MD) (55-69.9 mm), and high diameter (HD) (≥70 mm). AAA was characterized by abundant microvessels in the media and adventitia with perivascular infiltration of CD45-positive cells. Like endothelial cell markers, cyclooxygenase (COX)-2 and the microsomal isoform of prostaglandin E synthase (mPGES-1) transcripts were increased in AAA (4.4- and 1.4-fold, respectively). Both enzymes were localized in vascular cells and leukocytes, with maximal expression in the LD group, whereas leukocyte markers display a maximum in the MD group, suggesting that the upregulation of COX-2/mPGES-1 precedes maximal leukocyte infiltration. Plasma and in vitro tissue secreted levels of PGE2 metabolites were higher in AAA than in controls (plasma-controls, 19.9 ± 2.2; plasma-AAA, 38.8 ± 5.5 pg/ml; secretion-normal aorta, 16.5 ± 6.4; secretion-AAA, 72.9 ± 6.4 pg/mg; mean ± SEM). E-prostanoid receptor (EP)-2 and EP-4 were overexpressed in AAA, EP-4 being the only EP substantially expressed and colocalized with mPGES-1 in the microvasculature. Additionally, EP-4 mediated PGE2-induced angiogenesis in vitro. We provide new data concerning mPGES-1 expression in human AAA. Our findings suggest the potential relevance of the COX-2/mPGES-1/EP-4 axis in the AAA-associated hypervascularization.

Neutrophil-mediated tumour angiogenesis: subversion of immune responses to promote tumour growth

Neutrophils are rapidly responding, phagocytes that are an essential part of the host innate immune response to invading micro-organisms. Along with other leucocytes they also play a key role in directing repair at sites of tissue damage. Neutrophils accomplish many of their biological functions by releasing enzymes, anti-microbial agents and cytokines when stimulated to degranulate. There is now increasing evidence to show that tumours are able to recruit neutrophils by secreting a number of tumour cell or stromal-derived chemoattractants. Once within the tumour microenvironment neutrophils, like macrophages, are polarised into a pro-tumour phenotype that can foster tumour growth by secreting factors that directly influence tumour cell proliferation, drive immunosuppression and promote tumour angiogenesis. In this review we discuss the likely mechanisms by which neutrophils are recruited into the tumour and then elaborate on how these cells may induce tumour vascularisation by the secretion of powerful pro-angiogenic factors.

The CXCL1 rs4074 A allele is associated with enhanced CXCL1 responses to TLR2 ligands and predisposes to cirrhosis in HCV genotype 1-infected Caucasian patients

BACKGROUND & AIMS

CXCL1 is a ligand for CXC chemokine-receptor 2 expressed on hepatic stellate cells (HSC). Thus, CXCL1 might contribute to HSC activation and fibrogenesis. Here, we investigated whether the CXCL1 rs4074 polymorphism affects CXCL1 expression and progression of chronic hepatitis C virus (HCV) infection towards cirrhosis.

METHODS

The study involved 237 patients with chronic HCV genotype 1 infection (75 with cirrhosis) and 342 healthy controls. The CXCL1 rs4074 polymorphism was determined by a LightSNiP assay on the LightCycler system. CXCL1 serum levels and induction in response to HCV proteins were studied by ELISA.

RESULTS

Distributions of CXCL1 genotypes (GG/GA/AA) matched the Hardy-Weinberg equilibrium in all subgroups (HCV-associated cirrhosis: 29.3%/54.7%/16.0%; non-cirrhotic HCV infection: 45.1%/44.4%/10.5%, healthy controls: 46.2%/40.9%/12.9%). HCV-infected cirrhotic patients had a significantly greater CXCL1 rs4074 A allele frequency (43.3%) than patients without cirrhosis (32.7%, OR=1.573, p=0.03) and healthy controls (33.3%, OR=1.529, p=0.02). In vitro carriers of the A allele produced greater amounts of CXCL1 in response to TLR2-ligands including HCV core and NS3, and HCV-infected carriers of the CXCL1 rs4074 A allele had higher CXCL1 serum levels than those with the G/G genotype. Moreover, multivariate Cox-regression analysis confirmed age and the presence of a CXCL1 rs4074 A allele as risk factors for cirrhosis.

CONCLUSIONS

Enhanced production of CXCL1 in response to HCV antigens in carriers of the rs4074 A allele together with its increased frequency in cirrhotic patients with hepatitis C suggest the CXCL1 rs4074 A allele as a genetic risk factor for cirrhosis progression in hepatitis C.

Interaction between head and neck squamous cell carcinoma cells and fibroblasts in the biosynthesis of PGE2

Prostaglandin (PG)E(2) is relevant in tumor biology, and interactions between tumor and stroma cells dramatically influence tumor progression. We tested the hypothesis that cross-talk between head and neck squamous cell carcinoma (HNSCC) cells and fibroblasts could substantially enhance PGE(2) biosynthesis. We observed an enhanced production of PGE(2) in cocultures of HNSCC cell lines and fibroblasts, which was consistent with an upregulation of COX-2 and microsomal PGE-synthase-1 (mPGES-1) in fibroblasts. In cultured endothelial cells, medium from fibroblasts treated with tumor cell-conditioned medium induced in vitro angiogenesis, and in tumor cell induced migration and proliferation, these effects were sensitive to PGs inhibition. Proteomic analysis shows that tumor cells released IL-1, and tumor cell-induced COX-2 and mPGES-1 were suppressed by the IL-1-receptor antagonist. IL-1α levels were higher than those of IL-1β in the tumor cell-conditioning medium and in the secretion from samples obtained from 20 patients with HNSCC. Fractionation of tumor cell-conditioning media indicated that tumor cells secreted mature and unprocessed forms of IL-1. Our results support the concept that tumor-associated fibroblasts are a relevant source of PGE(2) in the tumor mass. Because mPGES-1 seems to be essential for a substantial biosynthesis of PGE(2), these findings also strengthen the concept that mPGES-1 may be \a target for therapeutic intervention in patients with HNSCC.

Tumor cells induce COX-2 and mPGES-1 expression in microvascular endothelial cells mainly by means of IL-1 receptor activation

Prostaglandin (PG) E(2) plays a key role in immune response, tumor progression and metastasis. We previously showed that macrovessel-derived endothelial cells do not produce PGE(2) enzymatically because they do not express the inducible microsomal PGE-synthase-1 (mPGES-1). Nevertheless, differences between macro- and micro-vessel-derived endothelial cells regarding arachidonic acid (AAc) metabolism profile have been reported. The present work was conducted to evaluate the expression of PGE(2)-pathway-related enzymes in human microvascular endothelial cells (HMVEC) in culture and to test the hypothesis that the tumor cell-HMVEC cross talk could increase mPGES-1 expression in HMVEC. We treated HMVEC in culture with human recombinant IL-1β. IL-1β induced PGE(2) release and COX-2 and mPGES-1 expression in terms of mRNA and protein, determined by real-time PCR and immunoblotting, respectively. HMVEC constitutively expressed mPGES-2 and cytosolic PGES (cPGES) and the IL-1β treatment did not modify their expression. PGE(2) synthesized by HMVEC from exogenous AAc was linked to mPGES-1 expression. Immunohistochemistry analysis confirmed mPGES-1 expression in microvessels in vivo. COX-2 and mPGES-1 were also induced in HMVEC by the conditioned medium from two squamous head and neck carcinoma cell lines. Conditioned medium from tumor cell cultures contained several cytokines including the IL-1β and IL-1α. Tumor cell-induced COX-2 and mPGES-1 in HMVEC was strongly inhibited by the IL-1-receptor antagonist, indicating the important implication of IL-1 in this effect. HMVEC could therefore contribute directly to PGE(2) formed in the tumor. Our findings support the concept that mPGES-1 could be a target for therapeutic intervention in patients with cancer.