616 research outputs found
Hybrid lipid self-assembling nanoparticles for brain delivery of microRNA
Hybrid self-assembling nanoparticles (SANPs) have been previously designed as novel drug delivery system that overcomes stability issues following long-term storage and with an easy scale-up. This system has been successfully used to deliver anionic-charged agents, e.g. bisphosphonates, in different types of tumors, such glioblastoma (GBM). Here, SANPs were tested and optimized for the delivery of nucleic acids, in particular of a specific microRNA, e.g. miR603, used for its potential role in controlling the chemoresistance in different forms of cancer, e.g. (GBM). To this aim, SANPs with different lipids were prepared and characterized, in terms of size, polydispersity index, zeta potential, miRNA encapsulation, stability in BSA, serum and hemolytic activity. Then, SANPs were tested in vitro on two different cell lines of GBM. Finally, miRNA biodistribution was tested in vivo in an orthotopic model of GBM. The majority of the formulations showed good technological characteristics and were stable in BSA and serum with a low hemolytic activity. The intracellular uptake studies on GBM cell lines showed that SANPs allow to achieve a higher miRNA delivery compared to others transfection agents, e.g. lipofectamine. Finally, in vivo biodistribution studies in an orthotopic of GBM demonstrated that the optimized SANP formulations, were able to deliver miRNA in different organs, e.g. the brain
Multifaceted Aspects of Metabolic Plasticity in Human Cholangiocarcinoma : An Overview of Current Perspectives
Cholangiocarcinoma (CCA) is a deadly tumor without an effective therapy. Unique metabolic and bioenergetics features are important hallmarks of tumor cells. Metabolic plasticity allows cancer cells to survive in poor nutrient environments and maximize cell growth by sustaining survival, proliferation, and metastasis. In recent years, an increasing number of studies have shown that specific signaling networks contribute to malignant tumor onset by reprogramming metabolic traits. Several evidences demonstrate that numerous metabolic mediators represent key-players of CCA progression by regulating many signaling pathways. Besides the well-known Warburg effect, several other different pathways involving carbohydrates, proteins, lipids, and nucleic acids metabolism are altered in CCA. The goal of this review is to highlight the main metabolic processes involved in the cholangio-carcinogeneis that might be considered as potential novel druggable candidates for this disease
Long-term efficacy and safety of vedolizumab in patients with inflammatory bowel diseases: A real-life experience from a tertiary referral center
Two benthic diatoms, nanofrustulum shiloi and striatella unipunctata, encapsulated in alginate beads, influence the reproductive efficiency of paracentrotus lividus by modulating the gene expression
Physiological effects of algal metabolites is a key step for the isolation of interesting bioactive compounds. Invertebrate grazers may be fed on live diatoms or dried, pelletized, and added to compound feeds. Any method may reveal some shortcomings, due to the leaking of wound-activated compounds in the water prior to ingestion. For this reason, encapsulation may represent an important step of bioassay-guided fractionation, because it may assure timely preservation of the active compounds. Here we test the effects of the inclusion in alginate (biocompatible and non-toxic delivery system) matrices to produce beads containing two benthic diatoms for sea urchin Paracentrotus lividus feeding. In particular, we compared the effects of a diatom whose influence on P. lividus was known (Nanofrustulum shiloi) and those of a diatom suspected to be harmful to marine invertebrates, because it is often present in blooms (Striatella unipunctata). Dried N. shiloi and S. unipunctata were offered for one month after encapsulation in alginate hydrogel beads and the larvae produced by sea urchins were checked for viability and malformations. The results indicated that N. shiloi, already known for its toxigenic effects on sea urchin larvae, fully conserved its activity after inclusion in alginate beads. On the whole, benthic diatoms affected the embryogenesis of P. lividus, altering the expression of several genes involved in stress response, development, skeletogenesis and detoxification processes. Interactomic analysis suggested that both diatoms activated a similar stress response pathway, through the up-regulation of hsp60, hsp70, NF-κB, 14-3-3 ε and MDR1 genes. This research also demonstrates that the inclusion in alginate beads may represent a feasible technique to isolate diatom-derived bioactive compounds
Dysregulation of NF–Y splicing drives metabolic rewiring and aggressiveness in colon cancer
NF-Y is an evolutionarily conserved transcription factor that binds specifically to the CCAAT
elements of eukaryotic genes, most of which frequently deregulated in cancer. NF-YA, the
regulatory subunit of the NF-Y complex, has two isoforms generated by alternative splicing,
NF-YAl and NF-YAs, which differ in the transactivation domain.
Transcriptomic data from The Cancer Genome Atlas (TCGA) database highlighted a
significant increase in the expression of NF-YAs at the expense of NF-YAl in colorectal cancer
(CRC), compared to healthy tissues. Despite this, high NF-YAl levels predict lower patients’
survival and distinguish the mesenchymal molecular subtype CMS4, which is characterized by
the worst prognosis.
Through the analysis of 3D cellular models, we demonstrated that altered expression of genes
related to extracellular matrix and epithelial-mesenchymal transition sustains enhanced
migratory and invasive behavior of NF-YAl-transduced cells. Moreover, the integration of
metabolomics, bioenergetics and transcriptional analyses demonstrated a direct role for NFYAl
in metabolic flexibility of cancer cells that adjust their metabolism in response to
environmental changes to potentiate migration. The zebrafish xenograft model confirmed the
metastatic potential triggered by NF-YAl in CRC cells.
Altogether, our data highlight the transcriptional role of NF-YAl in CRC aggressiveness and
suggest splice-switching strategies to hinder NF-YAl-induced metastatic dissemination
Design and development of topical liposomal formulations in a regulatory perspective
The skin is the absorption site for drug substances intended to treat loco-regional diseases, although its barrier properties limit the permeation of drug molecules. The growing knowledge of the skin structure and its physiology have supported the design of innovative nanosystems (e.g. liposomal systems) to improve the absorption of poorly skin-permeable drugs. However, despite the dozens of clinical trials started, few topically applied liposomal systems have been authorized both in the EU and the USA. Indeed, the intrinsic complexity of the topically applied liposomal systems, the higher production costs, the lack of standardized methods and the more stringent guidelines for assessing their benefit/risk balance can be seen as causes of such inefficient translation. The present work aimed to provide an overview of the physicochemical and biopharmaceutical characterization methods that can be applied to topical liposomal systems intended to be marketed as medicinal products, and the current regulatory provisions. The discussion highlights how such methodologies can be relevant for defining the critical quality attributes of the final product, and they can be usefully applied based on the phase of the life cycle of a liposomal product: to guide the formulation studies in the early stages of development, to rationally design preclinical and clinical trials, to support the pharmaceutical quality control system and to sustain post-marketing variations. The provided information can help define harmonized quality standards able to overcome the case-by-case approach currently applied by regulatory agencies in assessing the benefit/risk of the topically applied liposomal systems. Graphical abstract: [Figure not available: see fulltext.
Salmonella typhimurium and Escherichia coli dissimilarity: closely related bacteria with distinct metabolic profiles
Live attenuated strains of Salmonella typhimurium have been extensively investigated as vaccines for a number of infectious diseases. However, there is still little information available concerning aspects of their metabolism. S. typhimurium and Escherichia coli show a high degree of similarity in terms of their genome contents and metabolic networks. However, this work presents experimental evidence showing that significant differences exist in their abilities to direct carbon fluxes to biomass and energy production. It is important to study the metabolism of Salmonella in order to elucidate the formation of acetate and other metabolites involved in optimizing the production of biomass, essential for the development of recombinant vaccines. The metabolism of Salmonella under aerobic conditions was assessed using continuous cultures performed at dilution rates ranging from 0.1 to 0.67 h1, with glucose as main substrate. Acetate assimilation and glucose metabolism under anaerobic conditions were also investigated using batch cultures. Chemostat cultivations showed deviation of carbon towards acetate formation, starting at dilution rates above 0.1 h1. This differed from previous findings for E. coli, where acetate accumulation was only detected at dilution rates exceeding 0.4 h1, and was due to the lower rate of acetate assimilation by S. typhimurium under aerobic conditions. Under anaerobic conditions, both microorganisms mainly produced ethanol, acetate, and formate. A genome-scale metabolic model, reconstructed for Salmonella based on an E. coli model, provided a poor description of the mixed fermentation pattern observed during Salmonella cultures, reinforcing the different patterns of carbon utilization exhibited by these closely related bacteria. This article is protected by copyright. All rights reserved.Special thanks to Amadeus Azevedo for the HPLC analyses and technical assistance. The authors acknowledge the national funding received from CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brazil), the international cooperation project CAPES-FCT (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior/Brazil-Fundacao para a Ciencia e a Tecnologia/Portugal-Process 315/11), CAPES (Atracao de Jovens Talentos-Process 064922/2014-01) and to Fundacao para a Ciencia e Tecnologia the strategic funding of UID/BIO/04469/2013 unit
Magnetic Field Stimulated Transitions of Excited States in Fast Muonic Helium Ions
It is shown that one can stimulate, by using the present-day laboratory
magnetic fields, transitions between the sub-levels of fast
ions formating in muon catalyzed fusion. Strong fields also cause the
self-ionization from highly excited states of such muonic ions. Both effects
are the consequence of the interaction of the bound muon with the oscillating
field of the Stark term coupling the center-of-mass and muon motions of the
ion due to the non-separability of the collective and internal
variables in this system. The performed calculations show a possibility to
drive the population of the sub-levels by applying a field of a few
, which affects the reactivation rate and is especially important to the
-ray production in muon catalyzed fusion. It is also shown that
the splitting in due to the vacuum polarization slightly
decreases the stimulated transition rates.Comment: 5 figure
Efficacy and safety of combination therapy with everolimus and sorafenib for recurrence of hepatocellular carcinoma after liver transplantation.
Background Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is still associated with a dismal outcome. Combination therapy with everolimus (EVL) and vascular endothelial growth factor inhibitor sorafenib (SORA) is based on the role of both b-Raf and mammalian target of rapamycin/protein kinase B pathways in the pathogenesis of HCC and is being investigated in clinical practice. Methods This was a single-center retrospective analysis on LT recipients with unresectable HCC recurrence and undergoing combination therapy with EVL and SORA. Patients were included if they were switched to EVL+SORA at any time after surgery. Primary endpoint was overall survival (OS) after both LT and recurrence, and response to treatment based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) in the intention-to-treat (ITT) population. Secondary analysis was safety of combination therapy with EVL and SORA in the population of patients who received ≥1 dose of the study drug. Results Seven patients (100% male; median age 53 years [interquartile range (IQR) 9 years]) were considered for analysis. HCC recurrence was diagnosed at a median (IQR) interval since LT of 9 (126) months, and patients were administered EVL+SORA at a median interval since LT of 11 (126) months. Baseline immunosuppression was with tacrolimus (TAC) in 2 patients (28.6%), cyclosporine (CsA) in 2 (28.6%), and EVL monotherapy in 3 (42.8%). At a median (IQR) follow-up of 6.5 (14) months, 5 patients (71.4%) were alive, 4 of them (57.1%) with tumor progression according to the mRECIST criteria. Median (IQR) time to progression was 3.5 (12) months. Two patients died at a median (IQR) follow-up of 5 (1) months owing to tumor progression in 1 patient (14.3%) and sepsis in the other (14.3%). EVL monotherapy was achieved in 6 patients (85.7%), whereas 1patient (14.3%) could not withdraw from calcineurin inhibitor owing to acute rejection. Treatment complications were: hand-foot syndrome in 5 patients (71.4%), hypertension in 1 (14.3%), alopecia in 1 (14.3%), hypothyroidism in 1 (14.3%), diarrhea in 2 (28.6%), pruritus in 1 (14.3%), abdominal pain in 1 (14.3%), rash in 1 (14.3%), asthenia in 3 (42.8%), anorexia in 3 (42.8%), and hoarseness in 2 (28.6%). Adverse events led to temporary SORA discontinuation in 2 patients (28.6%) and to SORA dose reduction in 3 (42.8%). Conclusions Treatment of HCC recurrence after LT with a combination regimen of EVL+ SORA is challenging because of SORA-related complications. Longer follow-up periods and larger series are needed to better capture the impact of such combination treatment on tumor progression and patient survival.BACKGROUND:
Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is still associated with a dismal outcome. Combination therapy with everolimus (EVL) and vascular endothelial growth factor inhibitor sorafenib (SORA) is based on the role of both b-Raf and mammalian target of rapamycin/protein kinase B pathways in the pathogenesis of HCC and is being investigated in clinical practice.
METHODS:
This was a single-center retrospective analysis on LT recipients with unresectable HCC recurrence and undergoing combination therapy with EVL and SORA. Patients were included if they were switched to EVL+SORA at any time after surgery. Primary endpoint was overall survival (OS) after both LT and recurrence, and response to treatment based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) in the intention-to-treat (ITT) population. Secondary analysis was safety of combination therapy with EVL and SORA in the population of patients who received ≥1 dose of the study drug.
RESULTS:
Seven patients (100% male; median age 53 years [interquartile range (IQR) 9 years]) were considered for analysis. HCC recurrence was diagnosed at a median (IQR) interval since LT of 9 (126) months, and patients were administered EVL+SORA at a median interval since LT of 11 (126) months. Baseline immunosuppression was with tacrolimus (TAC) in 2 patients (28.6%), cyclosporine (CsA) in 2 (28.6%), and EVL monotherapy in 3 (42.8%). At a median (IQR) follow-up of 6.5 (14) months, 5 patients (71.4%) were alive, 4 of them (57.1%) with tumor progression according to the mRECIST criteria. Median (IQR) time to progression was 3.5 (12) months. Two patients died at a median (IQR) follow-up of 5 (1) months owing to tumor progression in 1 patient (14.3%) and sepsis in the other (14.3%). EVL monotherapy was achieved in 6 patients (85.7%), whereas 1patient (14.3%) could not withdraw from calcineurin inhibitor owing to acute rejection. Treatment complications were: hand-foot syndrome in 5 patients (71.4%), hypertension in 1 (14.3%), alopecia in 1 (14.3%), hypothyroidism in 1 (14.3%), diarrhea in 2 (28.6%), pruritus in 1 (14.3%), abdominal pain in 1 (14.3%), rash in 1 (14.3%), asthenia in 3 (42.8%), anorexia in 3 (42.8%), and hoarseness in 2 (28.6%). Adverse events led to temporary SORA discontinuation in 2 patients (28.6%) and to SORA dose reduction in 3 (42.8%).
CONCLUSIONS:
Treatment of HCC recurrence after LT with a combination regimen of EVL+ SORA is challenging because of SORA-related complications. Longer follow-up periods and larger series are needed to better capture the impact of such combination treatment on tumor progression and patient survival
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