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Glioblastoma multiforme (GBM) is the most lethal form of gliomas. New therapies are currently in development to tackle treatment limitations such as chemotherapy resistance. One mechanism of resistance may be the stress granules (SG) assembly, a stress-related cellular response that allows cells to recruit and protect mRNAs during stress. SG are composed of various proteins, being G3BP1 a core element that enucleates and results in SG assembly. Here, we aimed to evaluate the effects of inhibiting the G3PB1 expression in the chemotherapeutical-induced cell death of the U87 glioblastoma cell line.G3BP1 mRNA and protein expression were modulated with short-interference RNA (siRNA). The viability of U87 cells after Bortezomib (BZM), a proteasome inhibitor, and Temozolomide (TMZ), an alkylating agent, was assessed by MTT assay. Apoptosis was evaluated by staining cells with Annexin-V/7-AAD and analyzing by flow cytometry. Caspase-3 activation was evaluated by immunoblotting. The chorioallantoic membrane in vivo assay was used to evaluate angiogenesis.When G3BP1 was knocked-down, the SG assembly was reduced and the BZM-treated cells, but not TMZ-treated cells, had a significant increase in the apoptotic response. Corroborating this data, we observed increased Caspase-3 activation in the BZM-treated and G3BP1-knocked-down cells when compared to vehicle-treated and scramble-transfected cells. Worth mentioning, the conditioned culture medium of G3BP1-knocked-down BZM-treated cells inhibited angiogenesis when compared to controls.Our data suggest G3BP1 knockdown diminishes SG formation and stimulates BZM-induced apoptosis of U87 cells in vitro, in addition to inhibiting glioblastoma-induced angiogenesis in vivo.

Here, we characterize the Aspergillus fumigatus homologue ncsA Neuronal Calcium Sensor. We showed that ncsA is not an essential gene and ncsA growth was decreased in the presence of EGTA and SDS. Furthermore, the ncsA mutant is more resistant to calcium chloride. NcsA:mRFP localizes to the cytoplasm and its cellular localization is not affected by the cellular response to either calcium chloride or EGTA. The ncsA mutant strain is more sensitive to voriconazole, itraconazole, and amphotericin. Polar growth in the DeltancsA mutant was also considerably more affected by lovastatin than in the wild type strain. The Spitzenkörper can be visualized in both strains and although the vacuolar system does not seem to be very different, there is an increase in the staining intensity on the germling surface of the ncsA strain. NcsA promotes pmcA and pmcB expression and therefore there is a reduced expression of these ion pumps in the DeltancsA mutant background, and also of other genes involved in the response to calcium in A. fumigatus. The ncsA inactivation mutation is not causing loss of virulence in a low dose murine infection when compared to the corresponding wild type strain.

The involvement of TNF-α type 1 receptor (TNFR1) in memory deficits induced by sepsis was explored by using TNFR1 knockout (KO) mice. We reported that wild type (WT) mice presented memory deficits in the novel object recognition test 10 days after sepsis induced by cecum ligation and perforation (CLP). These deficits were not observed in TNFR1 KO mice. The involvement of serum and brain cytokines TNF-α, IL-1β, IL-6, IFN-γ and IL-10 was then investigated. TNFR1 KO mice had higher serum levels of TNF-α and IL-1β, and brain levels of TNF-α than WT mice. After CLP, the brain levels of TNF-α, IL-1β, IL-6 and IFN-γ increased in both WT and KO mice. Our next step was to determine the expression of inflammatory cytokines, BDNF and TrKb in the hippocampus. The absence of TNFR1 in mice subjected to polymicrobial sepsis resulted in higher BDNF expression in the hippocampus. In conclusion, after CLP, memory is preserved in the absence of TNFR1. This finding was associated with increased BDNF expression in the hippocampus.