International Meeting “Immunotherapy of Cancer: Challenges and Needs”

The main aims of the international meeting “Immunotherapy of Cancer: Challenges and Needs” were to review the state of the art of cancer immunotherapy and to identify critical issues which deserve special attention for promoting progress of research in this field, with a particular focus on the perspectives of clinical research. Novel concepts and strategies for identifying, monitoring and predicting effective responses to cancer immunotherapy protocols were presented, focused on the use of adjuvants (CpG oligonucleotides) or cytokines (IFN-alpha) to enhance the efficacy of cancer vaccines. Moreover, the possible advantages of using different types of dendritic cells (for active immunization strategies) or T cells (for adoptive immunotherapy protocols) were debated. A consensus was achieved on the need for enhancing the efficacy of cancer vaccines or adoptive cell immunotherapy by combining these strategies with other anti-cancer treatments, including chemotherapy. Finally, initiatives for promoting clinical research by establishing a strategic cooperation in the field of cancer immunotherapy based on the active participation of all the relevant actors, including public institutions responsible of Public Health, National Cancer Institutes, industry, representatives of regulatory bodies, and patients’ organizations were proposed.     

Interferon-alpha and cancer: mechanisms of action and new perspectives of clinical use

Interferons-alpha (IFN-alpha) are pleiotropic cytokines belonging to type I IFNs, extensively used in the treatment of patients with some types of cancer and viral disease. IFN-alpha can affect tumor cell functions by multiple mechanisms. In addition, these cytokines can promote the differentiation and activity of host immune cells. Early studies in mouse tumor models showed the importance of host immune mechanisms in the generation of a long-lasting antitumor response after treatment of the animals with IFN-alpha/beta. Subsequently, an ensemble of studies based on the use of genetically modified tumor cells expressing specific IFN molecules provided important information on the host-mediated antitumor mechanisms induced by the local production of IFN-alpha. Of note, several studies have then underscored new immunomodulatory effects of IFN-alpha, including activities on T cells and dendritic cells, which may lead to IFN-induced antitumor immunity. In addition, recent reports on new immune correlates in cancer patients responding to IFN-alpha represent additional evidence on the importance of the interactions of IFN-alpha with the immune system for the generation of a durable antitumor response. On the whole, this knowledge suggests the advantage of using these cytokines as adjuvants of cancer vaccines and for the in vitro generation of highly active dendritic cells to be utilized for therapeutic vaccination of cancer patients.     

Carotid Intima-Media Thickness Is Predicted by Combined Eotaxin Levels and Severity of Hepatic Steatosis at Ultrasonography in Obese Patients with Nonalcoholic Fatty Liver Disease

Background

Non-Alcoholic Fatty Liver Disease (NAFLD) is a distinct coronary artery disease (CAD) risk factor. The atherosclerotic process predisposing to CAD includes altered lipid profile and inflammatory processes. The available evidence suggests that increased circulating levels of eotaxin, an eosinophil chemoattractant cytokine implicated in allergic responses, are detected in the serum of patients with CAD. Relationships were sought between serum eotaxin on the one hand, and intima-media thickness—an early predictor of the atherosclerotic process, hepatic steatosis, arterial blood pressure values, as well as inflammation/immune markers and angiogenetic factors—on the other.

Methods

Eighty obese patients with NAFLD, diagnosed at ultrasonography, without evident cytolysis, formed our study population. Anthropometric measures, metabolic profile, serum concentrations of interleukin-1β, C-reactive protein, interleukin-6, fibrinogen, ferritin, TNF-α, spleen size, vascular endothelial growth factor, platelet-derived growth factor-BB and heat shock protein-70 were evaluated.

Results

Serum eotaxin concentrations were distinctly associated with TNF α, IL-6, IL-1β, VEGF and PDGF-BB levels but not with CRP, fibrinogen, heat shock protein-70 or spleen size. Among the metabolic and anthropometric parameters, a significant predictive power emerged when comparing eotaxin to insulin resistance, expressed as HOMA. NAFLD was distinctly associated with HOMA (P = 0.0005). Intima-media thickness was well predicted by both eotaxin levels and severity of NAFLD at ultrasonography, although no relation was detected between these last two variables.

Discussion and Conclusion

A role for insulin resistance in mediating the interplay between eotaxin and other inflammation/immune parameters could be evidenced in the induction/maintenance of atherosclerosis of obese patients with NAFLD.     

Assessing Archeal Indicators of Performance by RT-qPCR Methods During Anaerobic Co-digestion of Organic Wastes

Biogas is a renewable energy resource produced during the anaerobic digestion of various organic substrates. A wide community of microorganisms is involved, including methanogens. These Archaea are the biologic key to the process because they accomplish the methane-forming reaction. Despite its crucial role, the microbiome inside the digester is poorly understood. The aim of this work is to develop bioindicators of efficiency for the anaerobic process through the quantification and characterisation of the methanogens and sulphate-reducing bacteria. From a full-scale digester fed with organic wastes, 31 samples were collected. Temperature, pH, acidity, alkalinity and biogas quantity and quality were monitored over time. The methanogens were detected from the samples both in total and as belonging to different taxa units. These evaluations, by real-time quantitative PCR (RT-qPCR) methods, produced valuable results for Methanosarcina, Methanosaeta, Methanocorpusculaceae and sulphate-reducing bacteria. Methanosarcina was the most abundant family, followed by Methanocorpusculaceae and then Methanosaeta. The methanogen taxa are significantly and directly correlated with each other (p?<?0.05). Methanosaeta and Methanocorpusculaceae are present in significantly different amounts at different temperatures. While Methanosaeta levels also change when the organic load increases (t test, p?<?0.05), Methanosarcina is more tolerant, and its levels are quite constant. Methanosarcina and Methanosaeta are proposed to be bioindicators of the stability of the process (the first) and of susceptibility (the second) to detect early sufferance conditions in the digester. These methods will be useful in the control and optimisation of an eco-friendly waste-to-energy system.     

Rapid transmission of oxidative and nitrosative stress signals from roots to shoots in Arabidopsis.

Protein kinases play a central role in signal transduction pathways in eukaryotes. A highly conserved group of kinases, termed mitogen-activated-protein kinases (MAPKs) was shown to mediate many diverse stress responses. In plants, MAPKs were shown to function in resistance responses to many biotic and abiotic stresses. Here, we show that exposure of Arabidopsis roots to hydrogen peroxide or to nitric oxide resulted in rapid activation of protein kinases in the shoots that exhibited MAPK properties. The same pattern of kinases was induced by direct injection of these compounds into leaves, indicating accurate long-distance transmission of H2O2 and NO signals. These results are important for the understanding of redox signal transmission from the rhizosphere throughout the plant.     

Probing structural features of Alzheimer's amyloid-β pores in bilayers using site-specific amino acid substitutions

A current hypothesis for the pathology of Alzheimer's disease (AD) proposes that amyloid-β (Aβ) peptides induce uncontrolled, neurotoxic ion flux across cellular membranes. The mechanism of ion flux is not fully understood because no experiment-based Aβ channel structures at atomic resolution are currently available (only a few polymorphic states have been predicted by computational models). Structural models and experimental evidence lend support to the view that the Aβ channel is an assembly of loosely associated mobile β-sheet subunits. Here, using planar lipid bilayers and molecular dynamics (MD) simulations, we show that amino acid substitutions can be used to infer which residues are essential for channel structure. We created two Aβ(1-42) peptides with point mutations: F19P and F20C. The substitution of Phe19 with Pro inhibited channel conductance. MD simulation suggests a collapsed pore of F19P channels at the lower bilayer leaflet. The kinks at the Pro residues in the pore-lining β-strands induce blockage of the solvated pore by the N-termini of the chains. The cysteine mutant is capable of forming channels, and the conductance behavior of F20C channels is similar to that of the wild type. Overall, the mutational analysis of the channel activity performed in this work tests the proposition that the channels consist of a β-sheet rich organization, with the charged/polar central strand containing the mutation sites lining the pore, and the C-terminal strands facing the hydrophobic lipid tails. A detailed understanding of channel formation and its structure should aid studies of drug design aiming to control unregulated Aβ-dependent ion fluxes.     

Biodegradation of Trichloroethylene and Its Anaerobic Daughter Products in Freshwater Wetland Sediments

The wide range of redox conditions and diversity of microbial populations in organic-rich wetland sediments could enhance biodegradation of chlorinated solvents. To evaluate potential biodegradation rates of trichloroethylene (TCE) and its anaerobic daughter products (cis-1,2-dichloroethylene; trans-1,2-dichloroethylene; and vinyl chloride), laboratory microcosms were prepared under methanogenic, sulfate-reducing, and aerobic conditions using sediment and groundwater from a freshwater wetland that is a discharge area for a TCE contaminant plume. Under methanogenic conditions, biodegradation rates of TCE were extremely rapid at 0.30 to 0.37 d^-1 (half-life of about 2 days). Although the TCE biodegradation rate was slower under sulfate-reducing conditions (0.032 d^-1) than under methanogenic conditions, the rate was still two orders of magnitude higher than those reported in the literature for microcosms constructed with sandy aquifer sediments. In the aerobic microcosm experiments, biodegradation occurred only if methane consumption occurred, indicating that methanotrophs were involved. Comparison of laboratory-measured rates indicates that production of the 1,2-dichloroethylene isomers and vinyl chloride by anaerobic TCE biodegradation could be balanced by their consumption through aerobic degradation where methanotrophs are active in wetland sediment. TCE degradation rates estimated using field data (0.009 to 0.016 d^-1) agree with the laboratory-measured rates within a factor of 3 to 22, supporting the feasibility of natural attenuation as a remediation method for contaminated groundwater discharging in this wetland and other similar environments.     

Osimertinib and anti-HER3 combination therapy engages immune dependent tumor toxicity via STING activation in trans

Over the past decade, immunotherapy delivered novel treatments for many cancer types. However, lung cancer still leads cancer mortality, and non-small-cell lung carcinoma patients with mutant EGFR cannot benefit from checkpoint inhibitors due to toxicity, relying only on palliative chemotherapy and the third-generation tyrosine kinase inhibitor (TKI) osimertinib. This new drug extends lifespan by 9-months vs. second-generation TKIs, but unfortunately, cancers relapse due to resistance mechanisms and the lack of antitumor immune responses. Here we explored the combination of osimertinib with anti-HER3 monoclonal antibodies and observed that the immune system contributed to eliminate tumor cells in mice and co-culture experiments using bone marrow-derived macrophages and human PBMCs. Osimertinib led to apoptosis of tumors but simultaneously, it triggered inositol-requiring-enzyme (IRE1α)-dependent HER3 upregulation, increased macrophage infiltration, and activated cGAS in cancer cells to produce cGAMP (detected by a lentivirally transduced STING activity biosensor), transactivating STING in macrophages. We sought to target osimertinib-induced HER3 upregulation with monoclonal antibodies, which engaged Fc receptor-dependent tumor elimination by macrophages, and STING agonists enhanced macrophage-mediated tumor elimination further. Thus, by engaging a tumor non-autonomous mechanism involving cGAS-STING and innate immunity, the combination of osimertinib and anti-HER3 antibodies could improve the limited therapeutic and stratification options for advanced stage lung cancer patients with mutant EGFR.Subject terms: Non-small-cell lung cancer, Prognostic markers, Experimental models of disease, Preclinical research, Growth factor signalling