Αρχειοθήκη ιστολογίου

Κυριακή 2 Οκτωβρίου 2022

Pro-drug Nanoparticle Loaded Supramolecular Hydrogels for Drug Delivery to IDH1 Wild-Type Glioblastoma

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
A hyaluronic acid-based hydrogel with mechanical properties comparable to human brain tissue is being investigated as an implantable drug-delivery vehicle for post-surgical treatment of IDH1 wild-type glioblastoma (GBM). Hydrogels are to be loaded with polymeric pro-drug nanoparticles to enable controlled drug release and increased drug penetration through brain parenchyma for enhanced treatment of residual disease within and beyond the invasive margin.
METHOD
A panel of patient-derived glioblastoma cell lines resected from tumour core and invasive margin, have been used to generate tumour spheroids. Chemotherapeutic drug screening has been performed to select lead compounds for formulation and gel loading. Synergies of drug combinations have been studied for potential combination loading. Upcoming work will investigate nanoparticle internalisation, spheroid penetration and prodrug nanoparticle potency. Nanoparticle loaded hydrogels are then to be studied for validation of effective in vitro application.
RESULTS
Current results demonstrate that patient-derived cell lines can generate robust, reproducible tumour spheroids with diameters approx. 350-400 µm. Patient-to-patient differences in drug potencies were observed, with differences also noted between counterpart core and marginal cells from the same patients, illustrating the importance of using patient-derived cells and distinct regional cells to study heterogenous disease such as GBM. Drug combination experiments indicated synergy of topoisomerase I inhibitor (Irinotecan) with PARP inhibitor (Ola-parib). Interestingly, combination of PARP inhibition with topoisomerase II inhibitors (Doxorubicin, Etoposide) was found not synergistic.
CONCLUSION
Together, data gathered on single drug and drug-drug combinations will inform upcoming formulation and in vitro application of hydrogels planned, with eventual translation to pre-clinica l in vivo models.
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Hull’s Magic Box: Keeping Brain Tumour Biopsies “Alive” in the Lab Brings Research Opportunities for New Therapies and Earlier Diagnosis of Brain Tumour

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Assess/evaluate apoptosis in GBM samples maintained on a microfluidics system in response to GSK3368715 and other PRMT inhibitors, currently in clinical trials, with the ultimate goal of synergising with personalised patient care and precision medicine. Investigate the effect of treating GBM biopsies on-chip with PRMT inhibitors at the molecular level, including RNA and protein modifications.
METHOD
GBM biopsies are received from Hull Royal Infirmary and maintained on-chip for 8-days. They are perfused with media, at a rate of 3 μl/min, mimicking the in vivo environment and allowing real-time analysis of tumour behaviour. PRMT inhibitors, such as GSK3368715, are added to the media, in conjunction with TMZ, to determine their efficacy ex vivo using a range of techniques, such as: immunohistochemistry, cell viability assays, protein analysis and RNA-sequencing.
RESULTS
We show that PRMT inhibition increases apoptos is five-fold above the control, untreated GBM-on-chip samples. This is compounded by cell viability assays, which have indicated that cell viability in these post-chip tissues is reduced by 30% upon treatment with 1μM GSK3368715. Additionally, western blot analysis has indicated that PRMT inhibition with GSK3368715 appears to switch the methylation status of fused-in-sarcoma (FUS) protein in GBM biopsies.
CONCLUSION
These results indicate that PRMT inhibition may not only be a viable target for GBM therapy, but could also highlight a mechanism for re-sensitising MGMT-negative GBM to TMZ. This data produces an exciting argument for further research into the use of this novel inhibitor for improving prognosis for patients diagnosed with this devastating disease.
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Multifocal and Multicentric Glioblastomas: A 10 Year Single Centre Experience

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
The aims of this study are to share our experience of a large series of multifocal/multicentric glioblastomas (mGBM) and analyse the clinical, histological/molecular and neuroimaging characteristics as well as the outcomes of the patients in order to inform and contribute to future patient care.
METHOD
We conducted a retrospective single centre study of all multifocal/multicentric glioblastomas treated at our institution over a 10 year period. Data was collected from electronic patient records including patient demographics, clinical presentation, diagnostic imaging, treatment plans and histopathology/molecular findings. Time to recurrence/progression and overall survival was assessed.
RESULTS
1158 glioblastomas were treated surgically over this time period of which 121 multifocal/multicentric tumours were identified (10.4%). The median age at diagnosis was 63 years with a slight male predominance (54.5%). Half of all patients (61/121) presented with focal neurological deficits. 69% of patients underwent a craniotomy for diagnosis/debulking of the larger enhancing component of the tumour whilst 31% underwent only a biopsy. The median time to recurrence/progression was 154 days. Median length of survival was 269 days. Those who underwent craniotomy had significantly prolonged survival compared to biopsy alone 301 vs 198 days (p= 0.027) as did those who had a near total resection 401 vs 269 for subtotal resection (P=0.006) and those < 60 years (p=< 0.001). 88% of patients were IDH1 wildtype. Radiotherapy and chemotherapy confer a significant survival advantage when compared with no further treatment (p<0.001).
CONCLUSION
Near total resection of the larger enhancing component and post-operative chemo/radiotherapy can offer prolonged survival in patients with mGBM.
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Carcinomatous Meningitis Management

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Carcinomatous meningitis (CM) arises following metastatic deposition of neoplastic cells in the meninges triggering a complex series of pathological changes, typically representing a terminal complication of underlying malignancy. No uniform management strategy exists for CM patients, despite research highlighting numerous treatment modalities. We present a single centre retrospective study of CM patients managed over a ten year period, along with analysis of current and future treatment modalities for CM.
METHOD
Patient datasets were identified using diagnostic codes. Inclusion criteria were patients with malignant cells identified in CSF, or those with radiological features consistent with CM with a background of cancer and supporting clinical features. Data regarding patient symptomatology, management, and outcome were then gathered from electronic patient records.
RESULTS
Ten cases of carcinomatous meningitis were identified. The most common primary tumour site was breast (30%). The most common presenting symptoms were headache (70%), weakness (60%), vomiting (50%), and confusion (50%). Radiological evidence of CM in the form of leptomeningeal enhancement was noted in 60% of cases. Management of CM cases was variable – six patients underwent no further anti-cancer treatment, two patients underwent chemotherapy, and two patients were planned for radiotherapy. Median length of survival from time of CM diagnosis was 30 days (IQR 15 – 63).
CONCLUSION
CM patients have a poor prognosis, and significant variability exists in management. New therapeutic options are emerging, particularly in the field of targeted biologic therapies, and engagement with specialist oncology teams is recommended. Early palliative care support is essential in the management of CM patients.
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Identification of an Inflammatory Biomarker Signature in Plasma-Derived Extracellular Vesicles of Glioblastoma Patients

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Description of effective biomarkers present in biofluids could prove invaluable in GBM diagnosis. Extracellular vesicles (EVs) are essential to intercellular crosstalk in the tumour bulk and circulating EVs have been described as a potential reservoir of GBM biomarkers. Therefore, EV-based liquid biopsies have been suggested as a promising tool for GBM
METHOD
Ethical approval was obtained for a prospective study of healthy donors and consenting GBM patients at the University Hospitals Sussex (Brighton). To identify GBM specific proteins, small EVs (sEVs) were isolated from plasma samples using differential ultracentrifugation and validated through Nanoparticles tracking analysis, transmission electron microscopy and detection of known sEVs markers such as CD9, CD63, CD81 and HSP70. sEVs content was characterised through mass spectrometry and bioinformatic tools.
RESULTS
Our data indicate the presence of a GBM infl ammatory biomarker signature comprising members of the complement and regulators of inflammation and coagulation including VWF, FCGBP, C3, PROS1, and SERPINA1. Bioinformatic analysis highlighted that all potential markers exclusively identified in patient samples had already been linked with either GBM diagnosis, prognosis or associated signalling, suggesting that sEVs protein cargo could mirror the landscape of the original tumour and that selective circulating sEV-derived proteins might be used as hallmarks for GBM patients.
CONCLUSION
this study is a step forward in the development of a non-invasive liquid biopsy approach for the identification of valuable biomarkers that could significantly improve GBM diagnosis and, consequently, patients' prognosis and quality of life.
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Survival and Prognostic Factors in Melanoma Brain Metastasis (MBM) Treated With Stereotactic Radiosurgery (SRS)

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Brain metastasis is a frequent complication in melanoma, ultimately affecting 40–60% of patients with metastatic disease1. In the era of immune checkpoint and small molecule inhibitor therapy, there is a need to identify patient, tumour and treatment characteristics which may predict an improved prognosis in patients receiving stereotactic radiosurgery (SRS) for melanoma brain metastases (MBM).
METHOD
Retrospective casenote review was carried out for all patients receiving SRS, including gammaknife and cyberknife, for MBM between 2014 – 2020 at Barts Cancer Centre. Overall survival (OS) was calculated using the Kaplan-Meier method. Differences between groups were assessed using the Log-rank (Mantel-Cox) test.
RESULTS
93 patients were treated with SRS for MBM, with a median of 15 patients treated per year. The median age at treatment decision was 60 years (range 26 – 90): 59% were male; 41% female. Median num ber of lesions treated was 2 (range 1 – 15). Survival data was available for 74 patients: median overall survival for all patients was 9.5 months, with no significant survival difference by gender nor treatment year (pre-2017 vs. post-2017). However, treatment of 1-2 brain lesions carried a better prognosis compared to 3 or more lesions (median 12.2 vs. 5.7 months, p = 0.0292).
CONCLUSION
Initial analysis reveals an improved overall survival when fewer MBM are present. Further analyses will examine the impact of the following factors on patient survival: status of extracranial metastases, symptomatic vs. asymptomatic brain metastasis, intratumoral haemorrhage, systemic therapy pre- and post-SRS, and corticosteroid use during and after SRS.
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Survival Outcomes of Stereotactic Radiotherapy for Ten or More Brain Metastases

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Discrepancies exist in the use of stereotactic radiotherapy (SRT) for patients with 10 or more brain metastases. Concerns include multiple metastases being associated with poor survival and the lack of prospective data. We analysed survival outcomes of these patients in a multi-centre cohort.
METHOD
We performed a retrospective cohort study of 511 consecutive patients from three SRT centres treated for brain metastases between January 2010 - August 2021, censored in January 2022. We assessed survival post-SRT of patients with ≥10 metastases against a matched group of 5-9 and 1-4 metastases using the logrank test for statistical testing. We used a multivariate Cox model to assess the relationship between overall survival and: number of metastases; total volume; primary malignancy; use of systemic anti-cancer therapies with intracranial penetrance; controlled extracranial disease. Results with p-values <0.05 were consid ered significant.
RESULTS
Survival data was available for all patients, and for 85-100% of factors in multivariate analysis. 63 patients had ≥10 metastases (median 19). Median survival was 13.3 months, compared with 15.1 and 19.0 months for the 5-9 and 1-4 metastasis groups respectively. Differences were not statistically significant (p-value 0.14). Increasing volume of disease (HR 1.05 [1.01-1.09], p-value: 0.01), non-small cell lung cancer (HR 3.5 [1.35-9.09] p-value: 0.01) and use of systemic anti-cancer therapy with intracranial penetrance (HR 0.239 [0.105-0.547] p-value: <0.01) had a statistically significant effect on survival in multivariate analysis.
CONCLUSION
Carefully selected patients with multiple metastases have acceptable survival outcomes following SRT and this approach should be more widely considered.
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IDHwt Glioblastomas Show Opposing Resistance Mechanisms Across Patients in Response to Standard Treatment

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Glioblastoma (GBM) is the most common primary malignant brain tumour in adults. Despite aggressive treatment, a resistant tumour recurs in practically all patients. We therefore aimed to better understand the mechanisms driving this treatment resistance through investigating changes in gene expression across pairs of primary and recurrent GBM tumours.
METHOD
We generated or acquired bulk tumour RNA sequencing data for primary and first recurrent tumours from 107 patients who received standard treatment. Differential expression analysis between primary and recurrent samples found that the most dysregulated genes were involved in neurodevelopment and neurodifferentiation. We therefore used a publicly available ChIP-seq database to identify DNA binding factors for which binding sites are enriched in the promotors of genes with the largest expression changes from primary to recurrent.
RESULTS
Jumonji and AT-Rich Inter acting Domain 2 (JARID2) was the most strongly enriched for binding to promotors of dysregulated genes. 65 patients showed an up-regulation and 42 showed a down-regulation of genes bound by this protein. The same set of JARID2 bound genes were found to be dysregulated in each direction, and correlated with the largest source of variation between samples in their response to treatment. Further enrichment analyses indicated that 'Up' responders may resist treatment through reduced proliferation and increased interaction with the tumour microenvironment, whereas 'Down' responders instead rely on a shift to mesenchymal cell states.
CONCLUSION
These results indicate that GBM tumours can be split into two subtypes that transcriptionally reprogramme in different directions through treatment and may benefit from different treatment approaches.
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Neurosurgically-Applied Chemotherapy for Childhood Brain Tumours Arising in the Posterior Fossa Using a Biodegradable Paste

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
This project aims to develop a local drug delivery system for treatment of childhood medulloblastoma (MB) and atypical teratoid/rhabdoid tumours (AT/RT), malignant brain neoplasms occurring in the posterior fossa for which prognoses remains poor. Our goal is to repurpose drug compounds reported as effective against MB and AT/RT, but which either cannot cross the blood-brain-barrier (BBB) or have not been assessed for localised delivery. We have developed a novel intra-cavity drug delivery system, consisting of polymer microparticles made from poly(DL-lactic-co-glycolic acid) and poly(ethylene glycol) (PLGA/PEG) which will be employed to release drugs over several weeks.
METHOD
Cell toxicity assays were undertaken using drugs of interest against an in vitro panel of relevant MB and AT/RT cell lines. PLGA/PEG paste incorporating the drugs were prepared and release kinetics assessed.
RESULTS
IC50 values of the drugs were assessed across all cell lines and a range of potencies were observed, with optimum conditions identified as dual treatments of PG545 (heparanse inhibitor) with CHIR99021 (glycogen synthase kinase-3 inhibitor) for MB and ribavirin (anti-viral) with CHIR99021 for AT/RT. Importantly, it was noted that the drugs retained their cytotoxicity following release from PLGA/PEG. Furthermore, release kinetics were finely tuned through careful control of the composition through addition of excipients and encapsulation of drugs in nanoparticles, and a library of formulations were prepared.
CONCLUSION
A local drug delivery system for MB and AT/RT has been developed and an optimum formulation, based upon in vitro cell assays and release kinetics, has been identified for in vivo efficacy studies in orthotopic models.
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Exploring a Link Between Alzheimer’s and Glioma by Investigating SORL1 Network

alexandrossfakianakis shared this article with you from Inoreader
Abstract
AIMS
Use bioinformatics methods to identify and validate associated proteins and genes in the SORL1 network. Generate a bank of patient derived cells in association with the Royal Preston Hospital BTNW tissue bank. Explore identified targets from the bioinformatics in patient derived cells.
METHOD
Proteins and genes associated with SORL1 and SORLA were identified on GeneCards. Connectivity mapping of known and predicted interactions linked to SORL1 was explored in STRING. For clinical validation differential expression was investigated by comparing genomic data from GTEX and TCGA, available at Xenabrowser. For survival analysis Kaplan-Meier curves were generated on cBioPortal. The five most differently expressed novel targets are taken forward for laboratory experiments using western blots for protein quantification and immunocytochemistry to identify and visualise target proteins.
RESULTS
A total of 73 genes (30 from GeneCards and 43 from STRING) were obtained. 63 genes from the generated SORL1-related network were shown to be differentially expressed whilst 40 were significantly different between low-surviving patients and high-surviving patients. The top five associated proteins are CKAP4, CTNND1, FN1, HSPA12A and SORCS3. CKAP4, CTNND1 and FN1 are highly expressed in both glioma and glioblastoma, but low expressed in healthy tissue. HSPA12A is low expressed in cancerous brain tissue and highly expressed in healthy samples. SORCS3 is differentially expressed in healthy samples and glioma, but significantly low expressed glioblastoma.
CONCLUSION
This project provides insight into SORL1 molecular relationships and function in tissue, cultured cells and serum from a patient cohort including demographics, disease progression and site.
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