Mitochondrial enzyme GLUD2 plays a critical role in glioblastoma progression

Background: Glioblastoma (GBM) is the most frequent and malignant primary brain tumor in adults and despite the progress in surgical procedures and therapy options, the overall survival remains very poor. Glutamate and α-KG are fundamental elements necessary to support the growth and proliferation of GBM cells. Glutamate oxidative deamination, catalyzed by GLUD2, is the predominant pathway for the production of α-KG. Methods: GLUD2 emerged from the RNA-seq analysis of 13 GBM patients, performed in our laboratory and a microarray analysis of 77 high-grade gliomas available on the Geo database. Thereafter, we investigated GLUD2 relevance in cancer cell behavior by GLUD2 overexpression and silencing in two different human GBM cell lines. Finally, we overexpressed GLUD2 in-vivo by using zebrafish embryos and monitored the developing central nervous system. Findings: GLUD2 expression was found associated to the histopathological classification, prognosis and survival of GBM patients. Moreover, through in-vitro functional studies, we showed that differences in GLUD2 expression level affected cell proliferation, migration, invasion, colony formation abilities, cell cycle phases, mitochondrial function and ROS production. In support of these findings, we also demonstrated, with in-vivo studies, that GLUD2 overexpression affects glial cell proliferation without affecting neuronal development in zebrafish embryos. Interpretation: We concluded that GLUD2 overexpression inhibited GBM cell growth suggesting a novel potential drug target for control of GBM progression. The possibility to enhance GLUD2 activity in GBM could result in a blocked/reduced proliferation of GBM cells without affecting the survival of the surrounding neurons

A human MMTV-like betaretrovirus linked to breast cancer has been present in humans at least since the Copper Age

The betaretrovirus Mouse Mammary Tumor Virus (MMTV) is the well characterized etiological agent of mammary tumors in mice. In contrast, the etiology of sporadic human breast cancer (BC) is unknown, but accumulating data indicate a possible viral origin also for these malignancies. The presence of MMTVenv-like sequences (MMTVels) in the human salivary glands and saliva supports the latter as possible route of interhuman dissemination. In the absence of the demonstration of a mouse-man transmission of MMTV, we considered the possibility that a cross-species transmission could have occurred in ancient times. Therefore, we investigated MMTVels in the ancient dental calculus, which originates from saliva and is an excellent material for paleovirology. The calculus was collected from 36 ancient human skulls, excluding any possible mouse contamination. MMTV-like sequences were identified in the calculus of 6 individuals dated from the Copper Age to the 17th century. The MMTV-like sequences were compared with known human endogenous betaretroviruses and with animal exogenous betaretroviruses, confirming their exogenous origin and relation to MMTV. These data reveal that a human exogenous betaretrovirus similar to MMTV has existed at least since 4,500 years ago and indirectly support the hypothesis that it could play a role in human breast cancer

Regeneração de espécies florestais nativas após colheita de reflorestamento de eucalipto.

O objetivo deste estudo foi avaliar a influência de diferentes tipos de manejo na regeneração e no desenvolvimento de espécies nativas arbustivas e arbóreas em área aberta após o corte de Eucalyptus urograndis. Avaliar a eficácia de diferentes metodologias para recomposição florestal é importante, pois contribui para a minimização de custos e maximização da sustentabilidade ambiental. O estudo foi feito em uma área pertencente à empresa International Paper, no Município de Brotas, SP. A área de estudo foi investigada antes da colheita, por meio da análise do banco de sementes no solo e da diversidade de espécies nativas jovens que se desenvolvem no sub-bosque do reflorestamento. Após a retirada das árvores adultas de E. urograndis, foi avaliada a influência da fertilização química e do controle químico herbáceo na área aberta. Emergiram das amostras do banco de sementes do sub-bosque 31 espécies, totalizando 520 indivíduos, das quais apenas 5 eram espécies arbóreas nativas. Com relação à diversidade das espécies nativas arbustivas e arbóreas, o levantamento feito no sub-bosque resultou em 51 espécies e, na área aberta, em 97, com 23 espécies comuns a ambas as áreas. Os resultados demonstram que as espécies herbáceas predominaram no banco de sementes, o qual não contribuiu para a formação florestal nem do sub-bosque nem da área aberta. Nas avaliações na área aberta, por um período de quatro anos, o número de espécies permaneceu o mesmo e o número de indivíduos totais diminuiu de 634 para 289 desde o primeiro levantamento. O número de indivíduos e a diversidade de espécies das parcelas tratadas não diferiram significativamente das parcelas sem nenhum tratamento.bitstream/item/124365/1/4509.pd

ANKRd44 gene silencing: A putative role in trastuzumab resistance in HER2-like breast cancer

Trastuzumab is an effective therapeutic treatment for Her2-like breast cancer; despite this most of these tumors develop resistance to therapy due to specific gene mutations or alterations in gene expression. Understanding the mechanisms of resistance to Trastuzumab could be a useful tool in order to identify combinations of drugs that elude resistance and allow a better response for the treated patients. Twelve primary biopsies of Her2+/hormone receptor negative (ER-/PgR-) breast cancer patients were selected based on the specific response to neoadjuvant therapy with Trastuzumab and their whole exome was sequenced leading to the identification of 18 informative gene mutations that discriminate patients selectively based on response to treatment. Among these genes, we focused on the study of the ANKRD44 gene to understand its role in the mechanism of resistance to Trastuzumab. The ANKRD44 gene was silenced in Her2-like breast cancer cell line (BT474), obtaining a partially Trastuzumab-resistant breast cancer cell line that constitutively activates the NF-kb protein via the TAK1/AKT pathway. Following this activation an increase in the level of glycolysis in resistant cells is promoted, also confirmed by the up-regulation of the LDHB protein and by an increased TROP2 protein expression, found generally associated with aggressive tumors. These results allow us to consider the ANKRD44 gene as a potential gene involved in Trastuzumab resistance

Prevalence and Prognostic Role of IDH Mutations in Acute Myeloid Leukemia: Results of the GIMEMA AML1516 Protocol

IDH1/2 mutations are common in acute myeloid leukemia (AML) and represent a therapeutic target. The GIMEMA AML1516 observational protocol was designed to study the prevalence of IDH1/2 mutations and associations with clinico-biological parameters in a cohort of Italian AML patients. We analyzed a cohort of 284 AML consecutive patients at diagnosis, 139 females and 145 males, of a median age of 65 years (range: 19–86). Of these, 38 (14%) harbored IDH1 and 51 (18%) IDH2 mutations. IDH1/2 mutations were significantly associated with WHO PS >2 (p < 0.001) and non-complex karyotype (p = 0.021) when compared to IDH1/2-WT. Furthermore, patients with IDH1 mutations were more frequently NPM1-mutated (p = 0.007) and had a higher platelet count (p = 0.036). At relapse, IDH1/2 mutations were detected in 6 (25%) patients. As per the outcome, 60.5% of IDH1/2-mutated patients achieved complete remission; overall survival and event-free survival at 2 years were 44.5% and 36.1%, respectively: these rates were similar to IDH1/2-WT. In IDH1/2-mutated patients, high WBC proved to be an independent prognostic factor for survival. In conclusion, the GIMEMA AML1516 confirms that IDH1/2 mutations are frequently detected at diagnosis and underlines the importance of recognizing IDH1/2-mutated cases up-front to offer the most appropriate therapeutic strategy, given the availability of IDH1/2 inhibitors

Self-Assembled Amphiphilic Fluorinated Random Copolymers for the Encapsulation and Release of the Hydrophobic Combretastatin A-4 Drug

Water-soluble amphiphilic random copolymers composed of tri(ethylene glycol) meth-acrylate (TEGMA) or poly(ethylene glycol) methyl ether methacrylate (PEGMA) and perfluoro-hexylethyl acrylate (FA) were synthesized by ARGET-ATRP, and their self-assembling and ther-moresponsive behavior in water was studied by dynamic light scattering (DLS) and UV-vis spec-troscopy. The copolymer ability to self-fold in single-chain nano-sized structures (unimer micelles) in aqueous solutions was exploited to encapsulate Combretastatin A-4 (CA-4), which is a very hy-drophobic anticancer drug. The cloud point temperature (Tcp) was found to linearly decrease with increasing drug concentration in the drug/copolymer system. Moreover, while CA-4 was preferen-tially incorporated into the unimer micelles of TEGMA-ran-FA, the drug was found to induce mul-ti-chain, submicro-sized aggregation of PEGMA-ran-FA. Anyway, the encapsulation efficiency was very high (≥81%) for both copolymers. The drug release was evaluated in PBS aqueous solutions both below and above Tcp for TEGMA-ran-FA copolymer and below Tcp, but at two different drug loadings, for PEGMA-ran-FA copolymer. In any case, the release kinetics presented similar profiles, characterized by linear trends up to ≈10–13 h and ≈7 h for TEGMA-ran-FA and PEGMA-ran-FA, respectively. Then, the release rate decreased, reaching a plateau. The release from TEG-MA-ran-FA was moderately faster above Tcp than below Tcp, suggesting that copolymer ther-moresponsiveness increased the release rate, which occurred anyway by diffusion below Tcp. Cy-totoxicity tests were carried out on copolymer solutions in a wide concentration range (5–60 mg/mL) at 37 °C by using Balb/3T3 clone A31 cells. Interestingly, it was found that the concentra-tion-dependent micro-sized aggregation of the amphiphilic random copolymers above Tcp caused a sort of “cellular asphyxiation” with a loss of cell viability clearly visible for TEGMA-ran-FA solutions (Tcp below 37 °C) with higher copolymer concentrations. On the other hand, cells in contact with the analogous PEGMA-ran-FA (Tcp above 37 °C) presented a very good viability (≥75%) with respect to the control at any given concentration

Y-shaped alkynylimidazoles as effective push-pull fluorescent dyes for luminescent solar concentrators (LSCs)

The synthesis of three 2-arylalkynyl-4,5-diarylimidazoles endcapped with typical electron-donating (ED) and electron-withdrawing (EW) groups (push-pull system) and their evaluation as fluorescent dyes for thin-film luminescent solar concentrators (LSCs) is described. These novel Y-shaped imidazole-based fluorophores were easily assembled in good chemical yields through a three-step synthetic sequence involving a double Suzuki arylation, followed by a dehydrogenative alkynylation, and a Knoevenagel condensation. Their optical and spectroscopic properties were analyzed both in solution and in poly(methyl methacrylate) (PMMA) films. All the molecules in PMMA films showed an intense, red-shifted emission between 540 and 575 nm with large Stokes shift (>120 nm), moderate-to-good fluorescence quantum yields (QY) and good device efficiencies (ηdev), especially for compound 3