Co-Culture Models: Key Players in In Vitro Neurotoxicity, Neurodegeneration and BBB Modeling Studies.

The biological barriers existing in the human body separate the blood circulation from the interstitial fluid in tissues. The blood-brain barrier (BBB) isolates the central nervous system from the bloodstream, presenting a dual role: the protection of the human brain against potentially toxic/harmful substances coming from the blood, while providing nutrients to the brain and removing metabolites. In terms of architectural features, the presence of junctional proteins (that restrict the paracellular transport) and the existence of efflux transporters at the BBB are the two major in vivo characteristics that increase the difficulty in creating an ideal in vitro model for drug permeability studies and neurotoxicity assessments. The purpose of this work is to provide an up-to-date literature review on the current in vitro models used for BBB studies, focusing on the characteristics, advantages, and disadvantages of both primary cultures and immortalized cell lines. An accurate analysis of the more recent and emerging techniques implemented to optimize the in vitro models is also provided, based on the need of recreating as closely as possible the BBB microenvironment. In fact, the acceptance that the BBB phenotype is much more than endothelial cells in a monolayer has led to the shift from single-cell to multicellular models. Thus, in vitro co-culture models have narrowed the gap between recreating as faithfully as possible the human BBB phenotype. This is relevant for permeability and neurotoxicity assays, and for studies related to neurodegenerative diseases. Several studies with these purposes will be also presented and discussed.

Domain and cell type-specific immunolocalisation of voltage-gated potassium channels in the mouse striatum.

Diverse classes of voltage-gated potassium channels (Kv) are integral to the variety of electrical activity patterns that distinguish different classes of neurons in the brain. A feature of their heterogenous expression patterns is the highly precise manner in which specific cell types target their location within functionally specialised sub-cellular domains. Although Kv expression profiles in cortical brain regions are widely reported, their immunolocalisation in sub-cortical areas such as the striatum, and in associated diseases such as Parkinson's disease (PD), remain less well described. Therefore, the broad aims of this study were to provide a high resolution immunolocalisation analysis of various Kv subtypes within the mouse striatum and assess their potential plasticity in a model of PD. Immunohistochemistry and confocal microscopy revealed that immunoreactivity for Kv1.1, 1.2 and 1.4 overlapped to varying degrees with excitatory and inhibitory axonal marker proteins suggesting these Kv subtypes are targeted to axons innervating striatal medium spiny neurons (MSNs). Immunoreactivity for Kv1.3 strongly overlapped with signal for mitochondrial marker proteins in MSN somata and dendrites. Kv1.5 immunoreactivity was expressed in parvalbumin-immunopositive neurons whereas Kv1.6 was located in cells immunopositive for microglia. Signal for Kv2.1 was concentrated on the somatic and proximal dendritic plasma membrane of MSNs, whilst immunoreactivity for Kv4.2 was targeted to their distal dendritic regions. Finally, striatal Kv2.1 expression, at both the mRNA and protein levels, was decreased in alpha-synuclein overexpressing mice, yet increased in alpha-synuclein knockout mice, compared to wild-type counterparts. The data indicate a variety of Kv expression patterns that are distinctive to the striatum and susceptible to pathology that mirrors PD. Furthermore, these findings advance our understanding of the molecular diversity of various striatal cell types, and potentially have implications for the homeostatic changes of MSN excitability during associated medical conditions such as PD.

Parosteal lipoma of the radius with posterior interosseous nerve palsy.

Parosteal lipoma is a rare benign soft tissue mesenchymal tumour that may impair limb motor function when located adjacent to neurovascular structures. We report a case of a woman in her 80s with a long-standing lesion in the forearm and consequent sensory and motor function changes. She was admitted for an elective excision of the lipoma. Postoperative evolution was favourable, with marked improvement of limb function. Our aim in sharing this case is to create awareness of these rare deep-seated lipomas that might originate nerve palsy and should therefore be excised as soon as possible to avoid neurological damage.

Investigating Glioblastoma Response to Hypoxia.

Glioblastoma (GB) is the most common and deadly type of primary malignant brain tumor with an average patient survival of only 15-17 months. GBs typically have hypoxic regions associated with aggressiveness and chemoresistance. Using patient derived GB cells, we characterized how GB responds to hypoxia. We noted a hypoxia-dependent glycolytic switch characterized by the up-regulation of HK2, PFKFB3, PFKFB4, LDHA, PDK1, SLC2A1/GLUT-1, CA9/CAIX, and SLC16A3/MCT-4. Moreover, many proangiogenic genes and proteins, including VEGFA, VEGFC, VEGFD, PGF/PlGF, ADM, ANGPTL4, and SERPINE1/PAI-1 were up-regulated during hypoxia. We detected the hypoxic induction of invasion proteins, including the plasminogen receptor, S100A10, and the urokinase plasminogen activator receptor, uPAR. Furthermore, we observed a hypoxia-dependent up-regulation of the autophagy genes, BNIP-3 and DDIT4 and of the multi-functional protein, NDRG1 associated with GB chemoresistance; and down-regulation of EGR1 and TFRC (Graphical abstract). Analysis of GB patient cohorts' revealed differential expression of these genes in patient samples (except SLC16A3) compared to non-neoplastic brain tissue. High expression of SLC2A1, LDHA, PDK1, PFKFB4, HK2, VEGFA, SERPINE1, TFRC, and ADM was associated with significantly lower overall survival. Together these data provide important information regarding GB response to hypoxia which could support the development of more effective treatments for GB patients.

The Transcriptomic Landscape of Gastric Cancer: Insights into Epstein-Barr Virus Infected and Microsatellite Unstable Tumors.

BACKGROUND: Epstein-Barr Virus (EBV) positive and microsatellite unstable (MSI-high) gastric cancer (GC) are molecular subgroups with distinctive molecular profiles. We explored the transcriptomic differences between EBV+ and MSI-high GCs, and the expression of current GC immunotherapy targets such as PD-1, PD-L1, CTLA4 and Dies1/VISTA. METHODS: Using Nanostring Technology and comparative bioinformatics, we analyzed the expression of 499 genes in 46 GCs, classified either as EBV positive (EBER in situ hybridization) or MSI-high (PCR/fragment analysis). PD-L1 protein expression was assessed by immunohistochemistry. RESULTS: From the 46 GCs, 27 tested MSI-high/EBV-, 15 tested MSS/EBV+ and four tested MSS/EBV-. The Nanostring CodeSet could segregate GCs according to MSI and, to a lesser extent, EBV status. Functional annotation of differentially expressed genes associated MSI-high/EBV- GCs with mitotic activity and MSS/EBV+ GCs with immune response. PD-L1 protein expression, evaluated in stromal immune cells, was lower in MSI-high/EBV- GCs. High mRNA expression of PD-1, CTLA4 and Dies1/VISTA and distinctive PD-1/PD-L1 co-expression patterns (PD-1high/PD-L1low, PD-1high/PDL1high) were associated with MSS/EBV+ molecular subtype and gastric cancer with lymphoid stroma (GCLS) morphological features. CONCLUSIONS: EBV+ and MSI-high GCs present distinct transcriptomic profiles. GCLS/EBV+ cases frequently present co-expression of multiple immunotherapy targets, a finding with putative therapeutic implications.

The Role of Hypoxia in Glioblastoma Invasion.

Glioblastoma multiforme (GBM), a grade IV astrocytoma, is the most common and deadly type of primary malignant brain tumor, with a patient's median survival rate ranging from 15 to 17 months. The current treatment for GBM involves tumor resection surgery based on MRI image analysis, followed by radiotherapy and treatment with temozolomide. However, the gradual development of tumor resistance to temozolomide is frequent in GBM patients leading to subsequent tumor regrowth/relapse. For this reason, the development of more effective therapeutic approaches for GBM is of critical importance. Low tumor oxygenation, also known as hypoxia, constitutes a major concern for GBM patients, since it promotes cancer cell spreading (invasion) into the healthy brain tissue in order to evade this adverse microenvironment. Tumor invasion not only constitutes a major obstacle to surgery, radiotherapy, and chemotherapy, but it is also the main cause of death in GBM patients. Understanding how hypoxia triggers the GBM cells to become invasive is paramount to developing novel and more effective therapies against this devastating disease. In this review, we will present a comprehensive examination of the available literature focused on investigating how GBM hypoxia triggers an invasive cancer cell phenotype and the role of these invasive proteins in GBM progression.

Laryngeal chondrosarcoma--ten years of experience.

INTRODUCTION: Laryngeal involvement by cartilaginous tumors is rare. However, although accounting for only 1% of laryngeal tumor pathology, they are the most frequently occurring non-epithelial neoplasms. The most probable location is the endolaryngeal surface of the cricoid cartilage. Their symptoms are variable, depending on the size and location, and may include hoarseness, stridor, and dyspnea. Treatment is based on surgical excision. Some centers take into account the degree of differentiation and whether it is a case of relapse when deciding to perform a radical resection. AIM: To evaluate this disease in a sample of the Portuguese population. METHODS: A review of the medical records from 2002 to 2012 by assessment of clinical processes was performed. Data on demographics, clinical treatments, and outcomes were collected. RESULTS: Six patients were included in the study. Five of them underwent total laryngectomy, and in one case, partial excision of the thyroid cartilage was performed. None of the patients had either metastases or tumor-related death. CONCLUSION: Laryngeal chondrosarcomas remain a rare disease of unknown etiology, with slow and insidious symptoms. The treatment is surgical, with favorable prognosis, and metastases rarely occur. The main concern regards their propensity to relapse.

Laryngeal chondrosarcoma - Ten years of experience / Condrossarcoma da laringe - 10 anos de casuística

INTRODUCTION: Laryngeal involvement by cartilaginous tumors is rare. However, although accounting for only 1% of laryngeal tumor pathology, they are the most frequently occurring non-epithelial neoplasms. The most probable location is the endolaryngeal surface of the cricoid cartilage. Their symptoms are variable, depending on the size and location, and may include hoarseness, stridor, and dyspnea. Treatment is based on surgical excision. Some centers take into account the degree of differentiation and whether it is a case of relapse when deciding to perform a radical resection. AIM: To evaluate this disease in a sample of the Portuguese population. METHODS: A review of the medical records from 2002 to 2012 by assessment of clinical processes was performed. Data on demographics, clinical treatments, and outcomes were collected. RESULTS: Six patients were included in the study. Five of them underwent total laryngectomy, and in one case, partial excision of the thyroid cartilage was performed. None of the patients had either metastases or tumor-related death. CONCLUSION: Laryngeal chondrosarcomas remain a rare disease of unknown etiology, with slow and insidious symptoms. The treatment is surgical, with favorable prognosis, and metastases rarely occur. The main concern regards their propensity to relapse. .

INTRODUÇÃO: O acometimento laríngeo por tumores cartilaginosos é raro. No entanto, apesar de representarem 1% da patologia tumoral laríngea, são as neoplasias não epiteliais mais frequentes. Localizam-se mais frequentemente na face endolaríngea da cartilagem cricóide. Tem sintomatologia variável consoante o tamanho e a localização, podendo incluir disfonia, estridor e dispneia. O tratamento é essencialmente cirúrgico. Alguns centros levam em conta o grau de diferenciação e de se tratar ou não de recidiva, quando da decisão de ressecção mais ou menos radical. OBJETIVO: Avaliar esta patologia numa amostra da população portuguesa. MÉTODO: Revisão da casuística no intervalo de tempo 2002-2012, através de consulta dos processos clínicos. Foram coligidos os dados demográficos e clínicos relevantes, os tratamentos efetuados e os resultados. RESULTADOS: Foram incluídos seis pacientes. Cinco foram submetidos à laringectomia total e um foi submetido à excisão da asa esquerda da cartilagem tiroide. Nenhum apresentou metástases ou morte relacionada com o tumor. CONCLUSÃO: Os condrossarcomas laríngeos permanecem como patologia rara, de etiologia desconhecida, com crescimento lento e clínica insidiosa. O tratamento é cirúrgico, com prognóstico favorável, com a metastização a ocorrer raramente. A maior preocupação decorre da sua propensão à recidiva. .

Cochlear implant rehabilitation outcomes in Waardenburg syndrome children.

OBJECTIVES: The purpose of this study was to review the outcomes of children with documented Waardenburg syndrome implanted in the ENT Department of Centro Hospitalar de Coimbra, concerning postoperative speech perception and production, in comparison to the rest of non-syndromic implanted children. METHODS: A retrospective chart review was performed for children congenitally deaf who had undergone cochlear implantation with multichannel implants, diagnosed as having Waardenburg syndrome, between 1992 and 2011. Postoperative performance outcomes were assessed and confronted with results obtained by children with non-syndromic congenital deafness also implanted in our department. Open-set auditory perception skills were evaluated by using European Portuguese speech discrimination tests (vowels test, monosyllabic word test, number word test and words in sentence test). Meaningful auditory integration scales (MAIS) and categories of auditory performance (CAP) were also measured. Speech production was further assessed and included results on meaningful use of speech Scale (MUSS) and speech intelligibility rating (SIR). RESULTS: To date, 6 implanted children were clinically identified as having WS type I, and one met the diagnosis of type II. All WS children received multichannel cochlear implants, with a mean age at implantation of 30.6±9.7months (ranging from 19 to 42months). Postoperative outcomes in WS children were similar to other nonsyndromic children. In addition, in number word and vowels discrimination test WS group showed slightly better performances, as well as in MUSS and MAIS assessment. CONCLUSIONS: Our study has shown that cochlear implantation should be considered a rehabilitative option for Waardenburg syndrome children with profound deafness, enabling the development and improvement of speech perception and production abilities in this group of patients, reinforcing their candidacy for this audio-oral rehabilitation method.