Background: Producing recombinant plant proteins expressed in Escherichia coli produce in high yields and in a soluble and functional form can be difficult. Under overexpression conditions, proteins frequently accumulate as insoluble aggregates (inclusion bodies) within the producing bacteria. We evaluated how the initial culture density, temperature and duration of the expression stage affect the production of some eukaryotic enzymes in E. coli. Findings: A high yield of active soluble proteins was obtained by combining early-log phase cultures and low temperatures for protein induction. When IPTG was added at OD₆₀₀ = 0.1 and cultures were maintained at 4°C for 48-72 h, the soluble protein yield was 3 fold higher than that obtained in the mid-log phase (OD₆₀₀ = 0.6). Besides, the target protein expression increased and the endogenous bacterial proteins reduced, thus making the protein purification process easier and more efficient. Conclusions: The protocol can be widely applied to proteins with a heterologous expression which was limited by loss of activity at high temperatures or by low soluble recombinant protein yield.

Glioblastoma (GBM) is the most common malignant primary tumor of the central nervous system. With no effective therapy, the prognosis for patients is terrible poor. It is highly heterogeneous and EGFR amplification is its most frequent molecular alteration. In this light, we aimed to examine the genetic heterogeneity of GBM and to correlate it with the clinical characteristics of the patients. For that purpose, we analyzed the status of EGFR and the somatic copy number alterations (CNAs) of a set of tumor suppressor genes and oncogenes. Thus, we found GBMs with high level of EGFR amplification, low level and with no EGFR amplification. Highly amplified tumors showed histological features of aggressiveness. Interestingly, accumulation of CNAs, as a measure of tumor mutational burden, was frequent and significantly associated to shortened survival. EGFR-amplified GBMs displayed both a higher number of concrete CNAs and a higher global tumor mutational burden than their no EGFR-amplified counterparts. In addition to genetic changes previously described in GBM, we found PARK2 and LARGE1 CNAs associated to EGFR amplification. The set of genes analyzed allowed us to explore relevant signaling pathways on GBM. Both PARK2 and LARGE1 are related to receptor tyrosine kinase/PI3K/PTEN/AKT/mTOR-signaling pathway. Finally, we found an association between the molecular pathways altered, EGFR amplification and a poor outcome. Our results underline the potential interest of categorizing GBM according to their EGFR amplification level and the usefulness of assessing the tumor mutational burden. These approaches would open new knowledge possibilities related to GBM biology and therapy.

Around 20% of meningiomas histologically benign may be clinically aggressive and recur. This strongly affects management of meningioma patients. There is a need to evaluate the potential aggressiveness of an individual meningioma. Additional criteria for better classification of meningiomas will improve clinical decisions as well as patient follow up strategy after surgery. The aim of this study was to determine the relationship between gene expression profiles and new metabolic subgroups of benign meningioma with potential clinical relevance. Forty benign and fourteen atypical meningioma tissue samples were included in the study. We obtained metabolic profiles by NMR and recurrence after surgery information for all of them. We measured gene expression by oligonucleotide microarray measurements on 19 of them. To our knowledge, this is the first time that distinct gene expression profiles are reported for benign meningioma molecular subgroups with clinical correlation. Our results show that metabolic aggressiveness in otherwise histological benign meningioma proceeds mostly through alterations in the expression of genes involved in the regulation of transcription, mainly the LMO3 gene. Genes involved in tumor metabolism, like IGF1R, are also differentially expressed in those meningioma subgroups with higher rates of membrane turnover, higher energy demand and increased resistance to apoptosis. These new subgroups of benign meningiomas exhibit different rates of recurrence. This work shows that benign meningioma with metabolic aggressiveness constitute a subgroup of potentially recurrent tumors in which alterations in genes regulating critical features of aggressiveness, like increased angiogenesis or cell invasion, are still no predominant. The determination of these gene expression biosignatures may allow the early detection of clinically aggressive tumors.

This work presents the development of a protocol based on the dynamic laser speckle designed to monitor the reaction of cancer cells of line MEL-RC08 to the application of the drug Colcemid in two different concentrations: 0.2 and $0.4μg/mL$. The protocol was designed using the forward scattering approach with an He-Ne laser of 632.8 nm illuminating the samples, a control, and two variations of Colcemid, being monitored along 8 h. The data were analyzed numerically in the time and in the frequency domain, and the results presented the ability of the technique to monitor the action of the drug, particularly Colcemid ($0.4μg/mL$).

Patients with nonalcoholic fatty liver disease (NAFLD) may show mild cognitive impairment (MCI). The neurological functions affected remain unclear. The aims were to: (1) Characterize the neuropsychological alterations in NAFLD patients; (2) assess the prevalence of impairment of neurological functions evaluated; (3) develop a new score for sensitive and rapid MCI detection in NAFLD; (4) assess differences in MCI features between patients with nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH); and (5) compare neuropsychological alterations in NAFLD patients with cirrhotic patients with MCI. Fifty-nine NAFLD patients and 53 controls performed psychometric tests assessing different neurological functions: PHES (Psychometric Hepatic Encephalopathy Score) battery, d2, Stroop, Oral SDMT (Symbol Digit Modalities Test), Digit Span, number-letter test, and bimanual and visual-motor coordination tests. NAFLD patients show impairment in attention, mental concentration, psychomotor speed, cognitive flexibility, inhibitory mental control, and working memory. We developed a new, rapid, and sensitive score based on the most affected parameters in NAFLD patients, unveiling that 32% of NAFLD show MCI. Prevalence was similar in NAFL (36%) or NASH (27%) patients, but lower in NAFLD than in cirrhosis (65%). MCI prevalence is significant in NAFLD patients. Psychometric testing is warranted in these patients to unveil MCI and take appropriate measures to reverse and prevent its progression.

Meningiomas add up to 25% of intracranial tumors. Although the majority is considered histologically benign, the prediction of their potential aggressiveness is still unclear. We studied the histopathology and aberrations of chromosomes 1p, 14, and 22 by FISH (fluorescence in situ hybridization) in histologically benign meningiomas of 70 patients for the purpose of defining the prognostic value of these alterations in tumoral progression and the risk of recurrence. According to the WHO histopathological criteria, the study set comprised 53 benign, 11 atypical, and 6 anaplastic meningiomas. In benign meningiomas, 25% of the cases displayed a normal karyotype, isolated monosomy 22 (36%), monosomy 22 + 1p deletion (14%), 1p deletion (10%), monosomy 22 + 14q deletion (5%), monosomy 22 + 1p deletion + 14q deletion (5%), or other alterations (5%). Grade II meningiomas presented losses in chromosome 14 in most of the cases (67%), and Grade III meningiomas showed alterations in chromosome 14 in all patients. We observed an overall relapse rate of 31%: recurrence was observed in 19% of Grade I meningiomas, 64% of Grade II, and 83% of Grade III. 9 out of 10 recurrent cases revealed abnormalities in chromosomes 1 and 14, which was a notably higher incidence compared to the series of tumors without relapse. Thus, benign meningiomas with cytogenetic alterations in chromosomes 1p and 14 may be more closely related to atypical meningiomas than benign meningiomas without these alterations, especially in terms of recurrence risk.