Contribution of EEG in transient neurological deficits

Identification of stroke mimics and ‘chameleons’ among transient neurological deficits (TND) is critical. Diagnostic workup consists of a brain imaging study, for a vascular disease or a brain tumour and EEG, for epileptiform discharges. The precise role of EEG in this diagnostic workup has, however, never been clearly delineated. However, this could be crucial in cases of atypical or incomplete presentation with consequences on disease management and treatment. We analysed the EEG patterns on 95 consecutive patients referred for an EEG within 7 days of a TND with diagnostic uncertainty. Patients were classified at the discharge or the 3-month follow-up visit as: ‘ischemic origin’, ‘migraine aura’, ‘focal seizure’, and ‘other’. All patients had a brain imaging study. EEG characteristics were correlated to the TND symptoms, imaging study, and final diagnosis. Sixty four (67%) were of acute onset. Median symptom duration was 45 min. Thirty two % were ‘ischemic’, 14% ‘migraine aura’, 19% ‘focal seizure’, and 36% ‘other’ cause. EEGs were recorded with a median delay of 1.6 day after symptoms onset. Forty EEGs (42%) were abnormal. Focal slow waves were the most common finding (43%), also in the ischemic group (43%), whether patients had a typical presentation or not. Epileptiform discharges were found in three patients, one with focal seizure and two with migraine aura. Non-specific EEG focal slowing is commonly found in TND, and may last several days. We found no difference in EEG presentation between stroke mimics and stroke chameleons, and between other diagnoses.     

TMC1 but not TMC2 is responsible for autosomal recessive nonsyndromic hearing impairment in Tunisian families

Hereditary nonsyndromic hearing impairment (HI) is extremely heterogeneous. Mutations of the transmembrane channel-like gene 1 (TMC1) have been shown to cause autosomal dominant and recessive forms of nonsyndromic HI linked to the loci DFNA36 and DFNB7/B11, respectively. TMC1 is 1 member of a family of 8 genes encoding transmembrane proteins. In the mouse, MmTmc1 and MmTmc2 are both members of Tmc subfamily A and are highly and almost exclusively expressed in the cochlea. The restricted expression of Tmc2 in the cochlea and its close phylogenetic relationship to Tmc1 makes it a candidate gene for nonsyndromic HI. We analyzed 3 microsatellite markers linked to the TMC1 and TMC2 genes in 85 Tunisian families with autosomal recessive nonsyndromic HI and without mutations in the protein-coding region of the GJB2 gene. Autozygosity by descent analysis of 2 markers bordering the TMC2 gene allowed us to rule out its association with deafness within these families. However, 5 families were found to segregate deafness with 3 different alleles of marker D9S1837, located within the first intron of the TMC1 gene. By DNA sequencing of coding exons of TMC1 in affected individuals, we identified 3 homozygous mutations, c.100C-->T (p.R34X), c.1165C-->T (p.R389X) and the novel mutation c.1764G-->A (p.W588X). We additionally tested 60 unrelated deaf Tunisian individuals for the c.100C-->T mutation. We detected this mutation in a homozygous state in 2 cases. This study confirms that mutations in the TMC1 gene may be a common cause for autosomal recessive nonsyndromic HI.     

Modal analysis of the multi-shaped coupled honeycomb structures used in satellites structural design

The authors present an experimentation demonstration and a numerical simulation using structural finite element analysis of assembled honeycomb plates used for satellites design. A detailed comprehension of the dynamics of the coupled structures is essential for the design and the development of new structures and to give the solution to problems of noise and vibration on existing structures. This comprehension passes by the study of the modal analysis, which makes it possible to describe, include/understand and model the behavior of the coupled structures. The knowledge of the vibration behavior of the coupled structures being able to take into account its environment is a difficult problem and the engineer often has recourse to artefacts to give an estimate of it. A modal analysis of a coupled system composed of two and three sandwich plates with aluminum skins and hexagonal honeycomb core in free vibrations is presented in this study under the Clumped–Free–Free–Free boundary conditions. In this paper, the comparative study has been performed using the experimental data. The results obtained in this paper show that a good agreement is observed between the finite elements results and the experimental methods by accepting an error about less than 6%.     

Transfection of MS-36 melanoma cells with gef gene inhibits proliferation and induces modulation of the cell cycle

The gef gene, found in Escherichia coli DNA, encodes a small (50 amino acids) protein which is related to cell-killing functions. We used the MS-36 melanoma cell line as an experimental model to examine the usefulness of the gef gene as a new strategy for cancer therapy. We transfected MS-36 cells using the pMAMneo vector, and induced gef gene expression with dexamethasone. This decreased the proliferation rate of MS-36TG by as much as 85% in comparison with MS-36 parental cells. The decrease in cell growth was accompanied with significant modifications of the cell cycle and morphology. The G1-phase gradually disappeared, with accumulation in the S-phase. However, studies with annexin V-FITC and 7-aminoactinomycin D failed to demonstrate induction of apoptosis. Morphological changes were an increase in cell size and the number of filopodia, and especially the appearance of pore-like alterations in the cell membrane which were not seen in parental cells. Our results demonstrate that the gef gene, a system independent of the administration of a prodrug, significantly reduces the proliferation of MS-36 cells. This gene may therefore be considered a new candidate for cancer gene therapy.     

IDH1/2 but not DNMT3A mutations are suitable targets for minimal residual disease monitoring in acute myeloid leukemia patients: a study by the Acute Leukemia French Association

Acute myeloid leukemia (AML) is a heterogeneous disease. Even within the same NPM1-mutated genetic subgroup, some patients harbor additional mutations in FLT3, IDH1/2, DNMT3A or TET2. Recent studies have shown the prognostic significance of minimal residual disease (MRD) in AML but it remains to be determined which molecular markers are the most suitable for MRD monitoring. Recent advances in next-generation sequencing (NGS) have provided the opportunity to use multiple molecular markers. In this study, we used NGS technology to assess MRD in 31 AML patients enrolled in the ALFA-0701 trial and harboring NPM1 mutations associated to IDH1/2 or DNMT3A mutations. NPM1 mutation-based MRD monitoring was performed by RTqPCR. IDH1/2 and DNMT3A mutations were quantified by NGS using an Ion Torrent Proton instrument with high coverage (2 million reads per sample). The monitoringof IDH1/2 mutations showed that these mutations were reliable MRD markers that allowed the prediction of relapse in the majority of patients. Moreover, IDH1/2 mutation status predicted relapse or disease evolution in 100% of cases if we included the patient who developed myelodysplastic syndrome. In contrast, DNMT3A mutations were not correlated to the disease status, as we found that a preleukemic clone with DNMT3A mutation persisted in 40% of the patients who were in complete remission, reflecting the persistence of clonal hematopoiesis.     

Metabolomic profile of cancer stem cell‐derived exosomes from patients with malignant melanoma

Malignant melanoma (MM) is the most aggressive and life‐threatening form of skin cancer. It is characterized by an extraordinary metastasis capacity and chemotherapy resistance, mainly due to melanoma cancer stem cells (CSCs). To date, there are no suitable clinical diagnostic, prognostic or predictive biomarkers for this neoplasia. Therefore, there is an urgent need for new MM biomarkers that enable early diagnosis and effective disease monitoring. Exosomes represent a novel source of biomarkers since they can be easily isolated from different body fluids. In this work, a primary patient‐derived MM cell line enriched in CSCs was characterized by assessing the expression of specific markers and their stem‐like properties. Exosomes derived from CSCs and serums from patients with MM were characterized, and their metabolomic profile was analysed by high‐resolution mass spectrometry (HRMS) following an untargeted approach and applying univariate and multivariate statistical analyses. The aim of this study was to search potential biomarkers for the diagnosis of this disease. Our results showed significant metabolomic differences in exosomes derived from MM CSCs compared with those from differentiated tumour cells and also in serum‐derived exosomes from patients with MM compared to those from healthy controls. Interestingly, we identified similarities between structural lipids differentially expressed in CSC‐derived exosomes and those derived from patients with MM such as the glycerophosphocholine PC 16:0/0:0. To our knowledge, this is the first metabolomic‐based study aimed at characterizing exosomes derived from melanoma CSCs and patients'' serum in order to identify potential biomarkers for MM diagnosis. We conclude that metabolomic characterization of CSC‐derived exosomes sets an open door to the discovery of clinically useful biomarkers in this neoplasia.

Abbreviations

CSCs

cancer stem cells

EVs

extracellular vesicles

HCs

healthy controls

HPLC

high‐performance liquid chromatography

HRMS

high‐resolution mass spectrometry

MM

malignant melanoma

MMPs

malignant melanoma patients

PCA

principal component analysis

PLS‐DA

partial least squares discriminant analysis

Q‐TOF‐MS

quadrupole time‐of‐flight mass spectrometer

ROC

receiver operating characteristic curve

TIC

total ion chromatograms

TME

tumour microenvironment

VIP

variable importance in projection

     

What’s new in treatment of pancreatic cancer: a patent review (2010–2017)

Introduction: Pancreatic cancer (PC) is one of the most lethal cancers, with a median overall survival of less than 1 year and a 5-year survival of ~5%. The poor survival rate is likely due to lack of early diagnosis, fast disease course, high metastasis rate and disappointing treatment outcome. Therefore, at this stage, any new method that provides a treatment against PC without the undesirable side effects of chemotherapy and radiation is urgently needed.

Areas covered: This review summarizes the latest advances in the treatment of PC through the patents published from 2010 to 2017. The patents reviewed include both new combinations of existing drugs and novel structures. New targets are proposed for developing new drugs.

Expert opinion: The patents reviewed entail different approaches which, on the one hand, improve the administration of existing drugs and therapies and, on the other, develop new drugs to act on novel targets. However, most of the new methods are in the first stage of development and need to be tested in vivo, in pre-clinical approaches and in clinical trials. Therefore, further assays will help confirm the activity, mechanisms of action, drug-drug interactions and other aspects that make a compound a good antitumoral agent.     

HER2-signaling pathway,JNK and ERKs kinases,and cancer stem-like cells are targets of Bozepinib

Identification of novel anticancer drugs presenting more than one molecular target and efficacy against cancer stem-like cells (CSCs) subpopulations represents a therapeutic need to combat the resistance and the high risk of relapse in patients. In the present work we show how Bozepinib [(RS)-2,6-dichloro-9-[1-(p-nitrobenzenesulfonyl)-1,2,3,5-tetrahydro-4,1-benzoxazepin-3-yl]-9H-purine], a small anti-tumor compound, demonstrated selectivity on cancer cells and showed an inhibitory effect over kinases involved in carcinogenesis, proliferation and angiogenesis. The cytotoxic effects of Bozepinib were observed in both breast and colon cancer cells expressing different receptor patterns. Bozepinib inhibited HER-2 signaling pathway and JNK and ERKs kinases. In addition, Bozepinib has an inhibitory effect on AKT and VEGF together with anti-angiogenic and anti-migratory activities. Moreover, the modulation of pathways involved in tumorigenesis by Bozepinib was also evident in microarrays analysis. Interestingly, Bozepinib inhibited both mamo- and colono-spheres formation and eliminated ALDH+ CSCs subpopulations at a low micromolar range similar to Salinomycin. Bozepinib induced the down-regulation of c-MYC, β-CATENIN and SOX2 proteins and the up-regulation of the GLI-3 hedgehog-signaling repressor. Finally, Bozepinib shows in vivo anti-tumor and anti-metastatic efficacy in xenotransplanted nude mice without presenting sub-acute toxicity. These findings support further studies on the therapeutic potential of Bozepinib in cancer patients.