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Recently, checkpoint inhibitors have been investigated in metastatic prostate cancer, however their overall effect is unclear and needs to be further investigated. Objectives: The aim of this systematic review is to investigate the oncological response of metastatic castration-resistant prostate cancer patients to immune checkpoint inhibitors. Methods: Based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement, a systematic review of the literature was conducted through online electronic databases and the American Society of Clinical Oncology (ASCO) Meeting Library. Eligible publications were selected after a staged screening and selection process. RevMan 5.4 software was employed to run the quantitative analysis and forest plots. Risk of bias assessment was conducted using the Cochrane tool and Newcastle–Ottawa Scale for the randomized and non-randomized trials, respectively. Results: From the 831 results retrieved, 8 studies including 2768 patients were included. There was no significant effect on overall survival (OS) (overall response (OR) = 0.98; Z = 0.42; p = 0.67). Meanwhile, progression-free survival (PFS) was significantly better with immune checkpoint inhibitors administration (OR = 0.85; Z = 3.9; p < 0.0001). The subgroup analysis for oncological outcomes based on programmed death ligand 1 (PD-L1) positivity status displayed no significant effect, except on prostate-specific antigen response rate (PSA RR) (OR = 3.25; Z = 2.29; p = 0.02). Based on DNA damage repair (DDR), positive patients had a significantly better PFS and a trend towards better OS and overall response rate (ORR); the ORR was 40% in positive patients compared to 20% in the negative patients (OR = 2.46; Z = 1.3; p = 0.19), while PSA RR was 23.5% compared to 14.3% (OR = 1.88; Z = 0.88; p = 0.38). Better PFS was clearly associated with DDR positivity (OR = 0.70; Z = 2.48; p = 0.01) with a trend towards better OS in DDR positive patients (OR = 0.71; Z = 1.38; p = 0.17). Based on tumor mutation burden (TMB), ORR was 46.7% with high TMB versus 8.8% in patients with low TMB (OR = 11.88; Z = 3.0; p = 0.003). Conclusions: Checkpoint inhibitors provide modest oncological advantages in metastatic castration-resistant prostate cancer. There are currently no good predictive indicators that indicate a greater response in some patients. [ABSTRACT FROM AUTHOR]

Carnosine (β-alanyl-L-histidine), a dipeptide, is an endogenous antioxidant widely distributed in excitable tissues like muscles and the brain. Carnosine is involved in cellular defense mechanisms against oxidative stress, including the inhibition of amyloid-beta (Aβ) aggregation and the scavenging of reactive species. Microglia play a central role in the pathogenesis of Alzheimer's disease, promoting neuroinflammation through the secretion of inflammatory mediators and free radicals. However, the effects of carnosine on microglial cells and neuroinflammation are not well understood. In the present work, carnosine was tested for its ability to protect BV-2 microglial cells against oligomeric Aβ1-42-induced oxidative stress and inflammation. Carnosine prevented cell death in BV-2 cells challenged with Aβ oligomers through multiple mechanisms. Specifically, carnosine lowered the oxidative stress by decreasing NO and O2−• intracellular levels as well as the expression of iNOS and Nox enzymes. Carnosine also decreased the secretion of pro-inflammatory cytokines such as IL-1β, simultaneously rescuing IL-10 levels and increasing the expression and the release of TGF-β1. Carnosine also prevented Aβ-induced neurodegeneration in mixed neuronal cultures challenged with Aβ oligomers, and these neuroprotective effects were completely abolished by SB431542, a selective inhibitor of the type-1 TGF-β receptor. Our data suggest a multimodal mechanism of action of carnosine underlying its protective effects on microglial cells against Aβ toxicity with a key role of TGF-β1 in mediating these protective effects. [ABSTRACT FROM AUTHOR]

Human amylin is a 37-residue peptide hormone (hA1-37) secreted by β-cells of the pancreas and, along with insulin, is directly associated with type 2 diabetes mellitus (T2DM). Amyloid deposits within the islets of the pancreas represent a hallmark of T2DM. Additionally, amylin aggregates have been found in blood vessels and/or brain of patients with Alzheimer's disease, alone or co-deposited with β-amyloid. The purpose of this study was to investigate the neuroprotective potential of human amylin in the context of endothelial-neuronal "cross-talk". We initially performed dose-response experiments to examine cellular toxicity (quantified by the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] MTT assay) of different hA17–29 concentrations in endothelial cells (RBE4). In the culture medium of these cells, we also measured heat shock protein B5 (HspB5) levels by ELISA, finding that even a sub-toxic concentration of hA17–29 (3 µM) produced an increase of HspB5. Using a cell medium of untreated and RBE4 challenged for 48 h with a sub-toxic concentration of hA17–29, we determined the potential beneficial effect of their addition to the medium of neuroblastoma SH-SY5Y cells. These cells were subsequently incubated for 48 h with a toxic concentration of hA17–29 (20 µM). We found a complete inhibition of hA17–29 toxicity, potentially related to the presence in the conditioned medium not only of HspB5, but also of vascular endothelial growth factor (VEGF). Pre-treating SH-SY5Y cells with the anti-Flk1 antibody, blocking the VEGF receptor 2 (VEGFR2), significantly decreased the protective effects of the conditioned RBE4 medium. These data, obtained by indirectly measuring VEGF activity, were strongly corroborated by the direct measurement of VEGF levels in conditioned RBE4 media as detected by ELISA. Altogether, these findings highlighted a novel role of sub-toxic concentrations of human amylin in promoting the secretion of proteic factors by endothelial cells (HspB5 and VEGF) that support the survival and proliferation of neuron-like cells. [ABSTRACT FROM AUTHOR]