Boosting antitumor response with PSMA-targeted immunomodulatory VLPs, harboring costimulatory TNFSF ligands and GM-CSF cytokine.

Therapeutic strategies based on immunomodulation have improved cancer therapy. Most approaches target co-stimulatory pathways or the inhibition of immunosuppressive mechanisms, to enhance immune response and overcome the immune tolerance of tumors. Here, we propose a novel platform to deliver targeted immunomodulatory signaling, enhancing antitumor response. The platform is based on virus-like particles derived from lentiviral capsids. These particles may be engineered to harbor multifunctional ligands on the surface that drive tropism to the tumor site and deliver immunomodulatory signaling, boosting the antitumor response. We generated virus-like particles harboring a PSMA-ligand, TNFSF co-stimulatory ligands 4-1BBL or OX40L, and a membrane-anchored GM-CSF cytokine. The virus-like particles are driven to PSMA-expressing tumors and deliver immunomodulatory signaling from the TNFSF surface ligands and the anchored GM-CSF, inducing T cell proliferation, inhibition of regulatory T cells, and potentiating elimination of tumor cells. The PSMA-targeted particles harboring immunomodulators enhanced antitumor activity in immunocompetent challenged mice and may be explored as a potential tool for cancer immunotherapy.

Alkaloid and acetogenin-rich fraction from Annona crassiflora fruit peel inhibits proliferation and migration of human liver cancer HepG2 cells.

Plant species from Annonaceae are commonly used in traditional medicine to treat various cancer types. This study aimed to investigate the antiproliferative potential of an alkaloid and acetogenin-rich fraction from the fruit peel of Annona crassiflora in HepG2 cells. A liquid-liquid fractionation was carried out on the ethanol extract of A. crassiflora fruit peel in order to obtain an alkaloid and acetogenin-rich fraction (AF-Ac). Cytotoxicity, proliferation and migration were evaluated in the HepG2 cells, as well as the proliferating cell nuclear antigen (PCNA), vinculin and epidermal growth factor receptor (EGFR) expression. In addition, intracellular Ca2+ was determined using Fluo4-AM and fluorescence microscopy. First, 9 aporphine alkaloids and 4 acetogenins that had not yet been identified in the fruit peel of A. crassiflora were found in AF-Ac. The treatment with 50 µg/mL AF-Ac reduced HepG2 cell viability, proliferation and migration (p < 0.001), which is in accordance with the reduced expression of PCNA and EGFR levels (p < 0.05). Furthermore, AF-Ac increased intracellular Ca2+ in the HepG2 cells, mobilizing intracellular calcium stores, which might be involved in the anti-migration and anti-proliferation capacities of AF-Ac. Our results support the growth-inhibitory potential of AF-Ac on HepG2 cells and suggest that this effect is triggered, at least in part, by PCNA and EGFR modulation and mobilization of intracellular Ca2+. This study showed biological activities not yet described for A. crassiflora fruit peel, which provide new possibilities for further in vivo studies to assess the antitumoral potential of A. crassiflora, especially its fruit peel.

Decreased nuclear distribution nudE-like 1 enzyme activity in an animal model with dysfunctional disrupted-in-schizophrenia 1 signaling featuring aberrant neurodevelopment and amphetamine-supersensitivity.

BACKGROUND: Interaction of nuclear-distribution element-like 1 with disrupted-in-schizophrenia 1 protein is crucial for neurite outgrowth/neuronal migration, and this interaction competitively inhibits nuclear-distribution element-like 1 peptidase activity. Nuclear-distribution element-like 1 activity is reduced in antipsychotic-naïve first-episode psychosis and in medicated chronic schizophrenia, with even lower activity in treatment-resistant schizophrenia. AIMS: The purpose of this study was to investigate in a rat model overexpressing human non-mutant disrupted-in-schizophrenia 1, with consequent dysfunctional disrupted-in-schizophrenia 1 signaling, the relation of nuclear-distribution element-like 1 activity with neurodevelopment and dopamine-related phenotypes. METHODS: We measured cell distribution in striatum and cortex by histology and microtomography, and quantified the basal and amphetamine-stimulated locomotion and nuclear-distribution element-like 1 activity (in blood and brain) of transgenic disrupted-in-schizophrenia 1 rat vs wild-type littermate controls. RESULTS: 3D assessment of neuronal cell body number and spatial organization of mercury-impregnated neurons showed defective neuronal positioning, characteristic of impaired cell migration, in striatum/nucleus accumbens, and prefrontal cortex of transgenic disrupted-in-schizophrenia 1 compared to wild-type brains. Basal nuclear-distribution element-like 1 activity was lower in the blood and also in several brain regions of transgenic disrupted-in-schizophrenia 1 compared to wild-type. Locomotion and nuclear-distribution element-like 1 activity were both significantly increased by amphetamine in transgenic disrupted-in-schizophrenia 1, but not in wild-type. CONCLUSIONS: Our findings in the transgenic disrupted-in-schizophrenia 1 rat allow us to state that decreased nuclear-distribution element-like 1 activity reflects both a trait (neurodevelopmental phenotype) and a state (amphetamine-induced dopamine release). We thus define here a role for decreased nuclear-distribution element-like 1 peptidase activity both for the developing brain (the neurodevelopmental phenotype) and for the adult (interaction with dopaminergic responses), and present nuclear-distribution element-like 1 activity in a novel way, as unifying neurodevelopmental with dysfunctional dopamine response phenotypes.

Expression of the type 3 InsP3 receptor is a final common event in the development of hepatocellular carcinoma.

BACKGROUND & OBJECTIVES: Hepatocellular carcinoma (HCC) is the second leading cause of cancer death worldwide. Several types of chronic liver disease predispose to HCC, and several different signalling pathways have been implicated in its pathogenesis, but no common molecular event has been identified. Ca2+ signalling regulates the proliferation of both normal hepatocytes and liver cancer cells, so we investigated the role of intracellular Ca2+ release channels in HCC. DESIGN: Expression analyses of the type 3 isoform of the inositol 1, 4, 5-trisphosphate receptor (ITPR3) in human liver samples, liver cancer cells and mouse liver were combined with an evaluation of DNA methylation profiles of ITPR3 promoter in HCC and characterisation of the effects of ITPR3 expression on cellular proliferation and apoptosis. The effects of de novo ITPR3 expression on hepatocyte calcium signalling and liver growth were evaluated in mice. RESULTS: ITPR3 was absent or expressed in low amounts in hepatocytes from normal liver, but was expressed in HCC specimens from three independent patient cohorts, regardless of the underlying cause of chronic liver disease, and its increased expression level was associated with poorer survival. The ITPR3 gene was heavily methylated in control liver specimens but was demethylated at multiple sites in specimens of patient with HCC. Administration of a demethylating agent in a mouse model resulted in ITPR3 expression in discrete areas of the liver, and Ca2+ signalling was enhanced in these regions. In addition, cell proliferation and liver regeneration were enhanced in the mouse model, and deletion of ITPR3 from human HCC cells enhanced apoptosis. CONCLUSIONS: These results provide evidence that de novo expression of ITPR3 typically occurs in HCC and may play a role in its pathogenesis.

Biocompatible Fluorescent Core-Shell Nanoconjugates Based on Chitosan/Bi2S3 Quantum Dots.

Bismuth sulfide (Bi2S3) is a narrow-bandgap semiconductor that is an interesting candidate for fluorescent biomarkers, thermoelectrics, photocatalysts, and photovoltaics. This study reports the synthesis and characterization of novel Bi2S3 quantum dots (QDs) functionalized using chitosan (CHI) as the capping ligands via aqueous "green" route at room temperature and ambient pressure. Transmission electron microscopy (TEM), UV-visible (UV-vis) spectroscopy, photoluminescence (PL) spectroscopy, dynamic light scattering (DLS), and zeta potential (ZP) analysis were used to characterize the hybrids made of biopolymer-functionalized Bi2S3 semiconductor nanocrystals. The results demonstrated that the CHI ligand was effective at nucleating and controlling the growth of water-soluble colloidal Bi2S3 nanoparticles. The average sizes of the Bi2S3 nanoparticles were significantly affected by the molar ratio of the precursors but less dependent on the pH of the aqueous media, leading to the formation of nanocrystals with average diameters varying from 4.2 to 6.7 nm. These surface-modified Bi2S3 nanocrystals with CHI exhibited photoluminescence in the visible spectral region. Moreover, the results of in vitro MTT (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide) assay with human osteosarcoma cells (SAOS) cell line demonstrated no cytotoxic response of the nanoconjugates.Furthermore, the results indicated that the Bi2S3 QD-CHI nanoconjugates showed HEK293T cell uptake; therefore, they can be potentially used as novel fluorescent nanoprobes for the in vitro bioimaging of cells in biomedical applications. Graphical Abstract Schematic representation of the biocompatible core-shell nanostructure of the chitosan/Bi2S3 quantum dot conjugates with photoluminescent properties.