58 research outputs found

    Immune system-related changes in preclinical GL261 glioblastoma under TMZ treatment : Explaining MRSI-based nosological imaging findings with RT-PCR analyses

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    Altres ajuts: Centro de Investigación Biomédica en Red-Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN [http://www.ciber-bbn.es/en, accessed on 18 March 2021], CB06/01/0010). UAB Predoctoral training programme (14ª Convocatoria PIF-19612, predoctoral fellowships for P.C.-P.). 2018 XARDI 00016/IU68-013944 (XarTEC SALUT).Glioblastomas (GB) are brain tumours with poor prognosis even after aggressive therapy. Previous work suggests that magnetic resonance spectroscopic imaging (MRSI) could act as a biomarker of efficient immune system attack onto GB, presenting oscillatory changes. Glioma-associated microglia/macrophages (GAMs) constitute the most abundant non-tumour cell type within the GB and can be polarised into anti-tumour (M1) or pro-tumour (M2) phenotypes. One of the mechanisms to mediate immunosuppression in brain tumours is the interaction between programmed cell death-1 ligand 1 (PD-L1) and programmed cell death-1 receptor (PD-1). We evaluated the subpopulations of GAMs in responding and control GB tumours to correlate PD-L1 expression to GAM polarisation in order to explain/validate MRSI-detected findings. Mice were evaluated by MRI/MRSI to assess the extent of response to treatment and with qPCR for GAMs M1 and M2 polarisation analyses. M1/M2 ratios and PD-L1 expression were higher in treated compared to control tumours. Furthermore, PD-L1 expression was positively correlated with the M1/M2 ratio. The oscillatory change in the GAMs prevailing population could be one of the key causes for the differential MRSI-detected pattern, allowing this to act as immune system activity biomarker in future work

    Platinum-Based Nanoformulations for Glioblastoma Treatment : The Resurgence of Platinum Drugs?

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    Current therapies for treating Glioblastoma (GB), and brain tumours in general, are inefficient and represent numerous challenges. In addition to surgical resection, chemotherapy and radiotherapy are presently used as standards of care. However, treated patients still face a dismal prognosis with a median survival below 15-18 months. Temozolomide (TMZ) is the main chemotherapeutic agent administered; however, intrinsic or acquired resistance to TMZ contributes to the limited efficacy of this drug. To circumvent the current drawbacks in GB treatment, a large number of classical and non-classical platinum complexes have been prepared and tested for anticancer activity, especially platinum (IV)-based prodrugs. Platinum complexes, used as alkylating agents in the anticancer chemotherapy of some malignancies, are though often associated with severe systemic toxicity (i.e., neurotoxicity), especially after long-term treatments. The objective of the current developments is to produce novel nanoformulations with improved lipophilicity and passive diffusion, promoting intracellular accumulation, while reducing toxicity and optimizing the concomitant treatment of chemo-/radiotherapy. Moreover, the blood-brain barrier (BBB) prevents the access of the drugs to the brain and accumulation in tumour cells, so it represents a key challenge for GB management. The development of novel nanomedicines with the ability to (i) encapsulate Pt-based drugs and pro-drugs, (ii) cross the BBB, and (iii) specifically target cancer cells represents a promising approach to increase the therapeutic effect of the anticancer drugs and reduce undesired side effects. In this review, a critical discussion is presented concerning different families of nanoparticles able to encapsulate platinum anticancer drugs and their application for GB treatment, emphasizing their potential for increasing the effectiveness of platinum-based drugs

    Advances in Preclinical/Clinical Glioblastoma Treatment: Can Nanoparticles Be of Help?

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    Simple Summary As one of the most lethal human cancers, glioblastoma treatment is a real challenge because of several resistance mechanisms, including limited drug entry into the central nervous system through the blood-brain barrier and the vast heterogeneity of this family of tumors. In the development of precision medicine, various nanoconstructs are being proposed to cross the BBB, specifically target GB tumors, release the therapeutic cargo in a controlled manner, and reduce therapeutic resistance. This review summarizes the different families of nanoparticles and approaches followed so far pursuing these aims. Glioblastoma multiforme (GB) is the most aggressive and frequent primary malignant tumor in the central nervous system (CNS), with unsatisfactory and challenging treatment nowadays. Current standard of care includes surgical resection followed by chemotherapy and radiotherapy. However, these treatments do not much improve the overall survival of GB patients, which is still below two years (the 5-year survival rate is below 7%). Despite various approaches having been followed to increase the release of anticancer drugs into the brain, few of them demonstrated a significant success, as the blood brain barrier (BBB) still restricts its uptake, thus limiting the therapeutic options. Therefore, enormous efforts are being devoted to the development of novel nanomedicines with the ability to cross the BBB and specifically target the cancer cells. In this context, the use of nanoparticles represents a promising non-invasive route, allowing to evade BBB and reducing systemic concentration of drugs and, hence, side effects. In this review, we revise with a critical view the different families of nanoparticles and approaches followed so far with this aim

    Protein kinase CK2 content in GL261 mouse glioblastoma

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    Glioblastoma (GBM) is the most prevalent and aggressive human glial tumour with a median survival of 14-15 months. Temozolomide (TMZ) is the standard chemotherapeutic choice for GBM treatment. Unfortunately, chemoresistence always ensues with concomitant tumour regrowth. Protein kinase CK2 (CK2) contributes to tumour development, proliferation, and suppression of apoptosis in cancer and it is overexpressed in human GBM. Targeting CK2 in GBM treatment may benefit patients. With this translational perspective in mind, we have studied the CK2 expression level by Western blot analysis in a preclinical model of GBM: GL261 cells growing orthotopically in C57BL/6 mice. The expression level of the CK2 catalytic subunit (CK2α) was higher in tumour (about 4-fold) and in contralateral brain parenchyma (more than 2-fold) than in normal brain parenchyma (p < 0.05). In contrast, no significant changes were found in CK2 regulatory subunit (CK2β) expression, suggesting an increased unbalance of CK2α/CK2β in GL261 tumours with respect to normal brain parenchyma, in agreement with a differential role of these two subunits in tumours

    DCE@urLAB: a dynamic contrast-enhanced MRI pharmacokinetic analysis tool for preclinical data

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    Background DCE@urLAB is a software application for analysis of dynamic contrast-enhanced magnetic resonance imaging data (DCE-MRI). The tool incorporates a friendly graphical user interface (GUI) to interactively select and analyze a region of interest (ROI) within the image set, taking into account the tissue concentration of the contrast agent (CA) and its effect on pixel intensity. Results Pixel-wise model-based quantitative parameters are estimated by fitting DCE-MRI data to several pharmacokinetic models using the Levenberg-Marquardt algorithm (LMA). DCE@urLAB also includes the semi-quantitative parametric and heuristic analysis approaches commonly used in practice. This software application has been programmed in the Interactive Data Language (IDL) and tested both with publicly available simulated data and preclinical studies from tumor-bearing mouse brains. Conclusions A user-friendly solution for applying pharmacokinetic and non-quantitative analysis DCE-MRI in preclinical studies has been implemented and tested. The proposed tool has been specially designed for easy selection of multi-pixel ROIs. A public release of DCE@urLAB, together with the open source code and sample datasets, is available at http://www.die.upm.es/im/archives/DCEurLAB/ webcite

    Intranasal Administration of Catechol-Based Pt(IV) Coordination Polymer Nanoparticles for Glioblastoma Therapy

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    Cisplatin has been described as a potent anticancer agent for decades. However, in the case of glioblastomas, it is only considered a rescue treatment applied after the failure of second-line treatments. Herein, based on the versatility offered by coordination chemistry, we engineered nanoparticles by reaction of a platinum (IV) prodrug and iron metal ions showing in vitro dual pH- and redox-sensitivity, controlled release and comparable cytotoxicity to cisplatin against HeLa and GL261 cells. In vivo intranasal administration in orthotopic preclinical GL261 glioblastoma tumor-bearing mice demonstrated increased accumulation of platinum in tumors, leading in some cases to complete cure and prolonged survival of the tested cohort. This was corroborated by a magnetic resonance imaging follow-up, thus opening new opportunities for intranasal glioblastoma therapies while minimizing side effects. The findings derived from this research showed the potentiality of this approach as a novel therapy for glioblastoma treatment

    Development of a predictor for human brain tumors based on gene expression values obtained from two types of microarray technologies

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    Development of molecular diagnostics that can reliably differentiate amongst different subtypes of brain tumors is an important unmet clinical need in postgenomics medicine and clinical oncology. A simple linear formula derived from gene expression values of four genes (GFAP, PTPRZ1, GPM6B, and PRELP) measured from cDNA microarrays (n=35) have distinguished glioblastoma and meningioma cases in a previous study. We herein extend this work further and report that the above predictor formula showed its robustness when applied to Affymetrix microarray data acquired prospectively in our laboratory (n=80) as well as publicly available data (n=98). Importantly, GFAP and GPM6B were both retained as being significant in the predictive model upon using the Affymetrix data obtained in our laboratory, whereas the other two predictor genes were SFRP2 and SLC6A2. These results collectively indicate the importance of the expression values of GFAP and GPM6B genes sampled from the two types of microarray technologies tested. The high prediction accuracy obtained in these instances demonstrates the robustness of the predictors across microarray platforms used. This result would require further validation with a larger population of meningioma and glioblastoma cases. At any rate, this study paves the way for further application of gene signatures to more stringent biopsy discrimination challenges. © 2010, Mary Ann Liebert, Inc.This work was funded by the EU-funded grants eTUMOUR (FP6-2002-LIFESCIHEALTH503094),HealthAgents (IST-2004-27214) and the Spanish grant MEDIVO2 (SAF 2005-03650). CIBER-BNN is an initiative of ‘‘Instituto de Salud Carlos III’’ (ISCIII, Spain).Peer Reviewe

    Synthesis and Validation of a Bioinspired Catechol-Functionalized Pt(IV) Prodrug for Preclinical Intranasal Glioblastoma Treatment

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    Simple Summary Glioblastoma (GB) is a type of brain cancer with a poor prognosis and few improvements in its treatment. One of the greatest difficulties in GB therapy lies in the fact that most of the drugs with high anticancer potential do not reach the brain and exert high therapeutic activity while minimizing side effects. To overcome these limitations, we focused on a catechol-based Pt(IV) prodrug (able to reverse cisplatin in a cellular environment) with the intention of repurposing Pt-based drugs as GB chemotherapeutic agents. Our in vitro results have corroborated the therapeutic effect of the synthesized complexes as comparable to cisplatin, and in vivo studies have demonstrated the potential of nose-to-brain delivery of this Pt(IV) prodrug for GB treatment. Glioblastoma is the most malignant and frequently occurring type of brain tumors in adults. Its treatment has been greatly hampered by the difficulty to achieve effective therapeutic concentration in the tumor sites due to its location and the blood-brain barrier. Intranasal administration has emerged as an alternative for drug delivery into the brain though mucopenetration, and rapid mucociliary clearance still remains an issue to be solved before its implementation. To address these issues, based on the intriguing properties of proteins secreted by mussels, polyphenol and catechol functionalization has already been used to promote mucopenetration, intranasal delivery and transport across the blood-brain barrier. Thus, herein we report the synthesis and study of complex 1, a Pt(IV) prodrug functionalized with catecholic moieties. This complex considerably augmented solubility in contrast to cisplatin and showed a comparable cytotoxic effect on cisplatin in HeLa, 1Br3G and GL261 cells. Furthermore, preclinical in vivo therapy using the intranasal administration route suggested that it can reach the brain and inhibit the growth of orthotopic GL261 glioblastoma. These results open new opportunities for catechol-bearing anticancer prodrugs in the treatment for brain tumors via intranasal administration

    UTILIZATION OF SUSTAINED LOW EFFICIENCY DIALYSIS IN CRITICAL PACIENTS: EXPERIENCE IN THE HOSPITAL DE CLÍNICAS – UFPR

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    Background: Sustained Low Efficiency Dialysis (SLED), a hybrid therapy of replacement renal function, has been introduced as an alternative of intermittent and continuous dialysis methods in acute renal failure. Aim: To demonstrate the experience of using SLED in patients admitted at Intensive Care Unit (ICU) and Semi-Intensive Care-Unit (SICU) of the Hospital de Clínicas of Universidade Federal do Paraná between April/2013 and October/2014. Methods: Data were collected from medical records of patients admitted to the ICU and SICU submitted to SLED by GENIUS System®, with eight hours session. The following demographic data were included: gender, age, presence of diabetes mellitus (DM), hypertension and chronic kidney disease (CKD), use of vasoactive drugs and mechanical ventilation. It was obtained plasma levels of urea, creatinine, sodium, potassium, phosphorus, magnesium, bicarbonate, glucose, oxygen saturation and oxygen and carbon dioxide partial pressure, in three stages: before, during the 4th hour and after the procedure (8th hour). Results: 41 SLED were performed in 17 patients, 8 women. 88% were under mechanical ventilation and use of vasoactive drugs. The mortality rate in hospital was 76%. Regarding to the presence of comorbidities, 35% of patients had DM, almost 60%, hypertension, and 17%, CKD. Medium percentage urea reduction was 62% ±8.4. Phosphorus (mg/dL) levels had significant reduction between first (4.09 ± 2.28) and eighth hour of treatment (2.03 ±1.04), p value<0.05. Conclusion: SLED technique was an effective and safe alternative to the traditional renal replacement therapy, with need of phosphorus replacement during treatment due to hypophosphatemia observed in most cases   Introdução: A Diálise Prolongada de Baixa Eficiência (DPBE), terapia híbrida de substituição da função renal, surgiu como alternativa aos métodos intermitentes e contínuos de diálise na insuficiência renal aguda. Objetivo: Demonstrar a experiência com a DPBE no tratamento de pacientes da Unidade de Terapia Intensiva (UTI) e do Centro de Terapia Semi-Intensiva (CTSI) do Hospital de Clínicas da Universidade Federal do Paraná (HC-UFPR) entre Abril/2013 e Outubro/2014. Materiais e Métodos: As informações foram coletadas dos prontuários de pacientes da UTI/CTSI, submetidos à DPBE (sistema GENIUS®) com duração de 8 horas. Incluíram-se dados demográficos como: sexo, idade, presença de diabetes mellitus (DM), hipertensão arterial sistêmica (HAS) e doença renal crônica (DRC), uso de drogas vasoativas (DVA) e de ventilação mecânica (VM). Foram obtidas dosagens plasmáticas de ureia, creatinina, sódio, potássio, fósforo, magnésio, bicarbonato, glicose, saturação de O2 e pressão parcial de O2 e de CO2 em três momentos: antes, na 4ª hora e após o procedimento (8ª hora). Resultados: 41 DPBE foram realizadas em 17 pacientes, 8 mulheres. 88% estavam em VM e DVA. A taxa de mortalidade no internamento foi de 76%. 35% apresentavam DM, quase 60%, HAS, e em torno de 17%, DRC. O percentual médio de redução de ureia (%) foi de 62 ± 8,4. O fósforo (mg/dL) reduziu significativamente entre primeira (4,09l ± 2,28) e oitava horas (2,03 ± 1,04), p<0,05. Conclusão: A DPBE demonstrou-se efetiva e segura em relação à diálise convencional, havendo necessidade de reposição de fósforo durante o tratamento devido à hipofosfatemia observada na maioria dos casos.                

    Non-invasive grading of astrocytic tumours from the relative contents of myo-inositol and glycine measured by in vivo MRS

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    Altres ajuts: INTERPRET (EU-IST1999-10310). This work was also partially funded by the Centro de Investigación Biomédica en Red - Bioingeniería, Biomateriales y Nanomedicina, which is an initiative of the Instituto de Salud Carlos III (Spain) co-funded by EU FEDER funds.MRI and MRS are established methodologies for evaluating intracranial lesions. One MR spectral feature suggested for in vivo grading of astrocytic tumours is the apparent myo-Inositol (mI) intensity (ca 3.55ppm) at short echo times, although glycine (gly) may also contribute in vivo to this resonance. The purpose of this study was to quantitatively evaluate the mI + gly contribution to the recorded spectral pattern in vivo and correlate it with in vitro data obtained from perchloric acid extraction of tumour biopsies. Patient spectra (n = 95) at 1.5T at short (20-31 ms) and long (135-136 ms) echo times were obtained from the INTERPRET MRS database (http://gabrmn.uab.es/interpretvalidateddb/). Phantom spectra were acquired with a comparable protocol. Spectra were automatically processed and the ratios of the (mI + gly) to Cr peak heights ((mI + gly)/Cr) calculated. Perchloric acid extracts of brain tumour biopsies were analysed by high-resolution NMR at 9.4T. The ratio (mI + gly)/Cr decreased significantly with astrocytic grade in vivo between low-grade astrocytoma (A2) and glioblastoma multiforme (GBM). In vitro results displayed a somewhat different tendency, with anaplastic astrocytomas having significantly higher (mI + gly)/Cr than A2 and GBM. The discrepancy between in vivo and in vitro data suggests that the NMR visibility of glycine in glial brain tumours is restricted in vivo
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