Search results for "SIM"

In silico and in vitro prediction of the toxicological effects of individual and combined mycotoxins.

2018

3-Acetyldeoxynivalenol (3-AcDON) and 15-acetyldeoxynivalenol (15-AcDON) are converted to deoxynivalenol (DON) in vivo and their simultaneous presence may increase DON intake. Mixtures of DON and its derivatives are a public health concern. In this study DON, 3-AcDON and 15-AcDON were evaluated in vitro and in silico. The in vitro cytotoxicity of DON and its derivatives individually and combined was determined by the Neutral Red (NR) assay in human hepatocarcinoma (HepG2) cells. The concentrations tested were from 1.25 to 15 μM (DON) and from 0.937 to 7.5 μM (DON derivatives). The IC50 values were from >15 to 2.55 μM (DON), from 1.77 to 1.02 μM (3-AcDON), and from 4.05 to 1.68 μM (15-AcDON).…

Identification of noncovalent proteasome inhibitors with high selectivity for chymotrypsin-like activity by a multistep structure-based virtual scree…

2016

Noncovalent proteasome inhibitors introduce an alternative mechanism of inhibition to that of covalent inhibitors, e.g. carfilzomib, used in cancer therapy. A multistep hierarchical structure-based virtual screening (SBVS) of the 65,375 NCI lead-like compound library led to the identification of two compounds (9 and 28) which noncovalently inhibited the chymotrypsin-like (ChT-L) activity (Ki = 2.18 and 2.12 μM, respectively) with little or no effects on the other two major proteasome proteolytic activities, trypsin-like (T-L) and post-glutamyl peptide hydrolase (PGPH) activities. A subsequent hierarchical similarity search over the full NCI database with the most active tripeptide-based inh…

Exploring the readthrough of nonsense mutations by non-acidic Ataluren analogues selected by ligand-based virtual screening

2016

Abstract Ataluren, also known as PTC124, is a 5-(fluorophenyl)-1,2,4-oxadiazolyl-benzoic acid suggested to suppress nonsense mutations by readthrough of premature stop codons in the mRNA. Potential interaction of PTC124 with mRNA has been recently studied by molecular dynamics simulations highlighting the importance of H-bonding and stacking π−π interactions. A series of non-acidic analogues of PTC124 were selected from a large database via a ligand-based virtual screening approach. Eight of them were synthesized and tested for their readthrough activity using the Fluc reporter harboring the UGA premature stop codon. The most active compound was further tested for suppression of the UGA non…

2019

During lytic herpes simplex virus 1 (HSV-1) infection, the expansion of the viral replication compartments leads to an enrichment of the host chromatin in the peripheral nucleoplasm. We have shown previously that HSV-1 infection induces the formation of channels through the compacted peripheral chromatin. Here, we used three-dimensional confocal and expansion microscopy, soft X-ray tomography, electron microscopy, and random walk simulations to analyze the kinetics of host chromatin redistribution and capsid localization relative to their egress site at the nuclear envelope. Our data demonstrated a gradual increase in chromatin marginalization, and the kinetics of chromatin smoothening arou…

Second-Line Treatment of Non-Small Cell Lung Cancer: Clinical, Pathological, and Molecular Aspects of Nintedanib

2017

Abstract: Lung carcinoma is the leading cause of death by cancer in the world. Nowadays, most patients will experience disease progression during or after first-line chemotherapy demonstrating the need for new, effective second-line treatments. The only approved second-line therapies for patients without targetable oncogenic drivers are docetaxel, gemcitabine, pemetrexed, and erlotinib and for patients with target-specific oncogenes afatinib, osimertinib, crizotinib, alectinib, and ceritinib. In recent years, evidence on the role of antiangiogenic agents have been established as important and effective therapeutic targets in non-small cell lung cancer (NSCLC). Nintedanib is a tyrosine kinas…

Integrating Liquid Biopsy and Radiomics to Monitor Clonal Heterogeneity of EGFR-Positive Non-Small Cell Lung Cancer

2020

BackgroundEGFR-positive Non-small Cell Lung Cancer (NSCLC) is a dynamic entity and tumor progression and resistance to tyrosine kinase inhibitors (TKIs) arise from the accumulation, over time and across different disease sites, of subclonal genetic mutations. For instance, the occurrence of EGFR T790M is associated with resistance to gefitinib, erlotinib, and afatinib, while EGFR C797S causes osimertinib to lose activity. Sensitive technologies as radiomics and liquid biopsy have great potential to monitor tumor heterogeneity since they are both minimally invasive, easy to perform, and can be repeated over patient’s follow-up, enabling the extraction of valuable information. Yet, to date, t…

Intermittent targeted therapies and stochastic evolution in patients affected by chronic myeloid leukemia

2016

Front line therapy for the treatment of patients affected by chronic myeloid leukemia (CML) is based on the administration of tyrosine kinase inhibitors, namely imatinib or, more recently, axitinib. Although imatinib is highly effective and represents an example of a successful molecular targeted therapy, the appearance of resistance is observed in a proportion of patients, especially those in advanced stages. In this work, we investigate the appearance of resistance in patients affected by CML, by modeling the evolutionary dynamics of cancerous cell populations in a simulated patient treated by an intermittent targeted therapy. We simulate, with the Monte Carlo method, the stochastic evolu…

Clinical utility of plasma-based digital next-generation sequencing in oncogene-driven non-small-cell lung cancer patients with tyrosine kinase inhib…

2019

[Objectives] Resistance to tyrosine-kinase inhibitors (TKIs) is a clinical challenge in patients with oncogene-driven non-small-cell lung cancers (NSCLC). We have analyzed the utility of next-generation sequencing (NGS) of cell-free circulating tumor DNA (ctDNA) to impact the clinical care of patients with TKI resistance.

Comprehensive cross-platform comparison of methods for non-invasive EGFR mutation testing : results of the RING observational trial

2020

Plasma samples from 72 EGFR‐mutant advanced NSCLC patients, collected upon progression to first‐line TKI, were analyzed by seven methodologies (two NGS‐based methods, three high‐sensitivity PCR‐based platforms, and two FDA‐approved methods). Our study demonstrates a good to excellent agreement between methodologies and supports the use of liquid biopsies for therapy decision‐making.

Identification of fatal outcome in a childhood nasopharyngeal carcinoma patient by protein expression profiling.

2017

Nasopharyngeal carcinoma (NPC) is a rare disease in children with good prognosis and high cure rate. Nevertheless, certain patients have an unfavorable prognosis due to development of refractory NPC that is unresponsive to any therapeutic strategies. The current study studies a case of a 17 years-old female with non-keratinizing NPC type IIb (T2N0M0), who passed away as a consequence of resistance to chemo-, radio- and β-interferon therapy, and to an allogenic stem cell transplantation. In order to identify factors that lead to treatment failure and fatal outcome, immunohistochemical analyses of different tumor biomarkers and hierarchical cluster analysis were performed and compared with th…