Long-term survival of patients with glioblastoma multiforme (GBM)

PDZK1 is correlated with DCE-MRI perfusion parameters in high-grade glioma

OBJECTIVE

This study investigated the relationship between PDZK1 expression and Dynamic Contrast-Enhanced MRI (DCE-MRI) perfusion parameters in High-Grade Glioma (HGG).

METHODS

Preoperative DCE-MRI scanning was performed on 80 patients with HGG to obtain DCE perfusion transfer coefficient (Ktrans), vascular plasma volume fraction (vp), extracellular volume fraction (ve), and reverse transfer constant (kep). PDZK1 in HGG patients was detected, and its correlation with DCE-MRI perfusion parameters was assessed by the Pearson method. An analysis of Cox regression was performed to determine the risk factors affecting survival, while Kaplan-Meier and log-rank tests to evaluate PDZK1's prognostic significance, and ROC curve analysis to assess its diagnostic value.

RESULTS

PDZK1 was upregulated in HGG patients and predicted poor overall survival and progression-free survival. Moreover, PDZK1 expression distinguished grade III from grade IV HGG. PDZK1 expression was positively correlated with Ktrans 90, and ve_90, and negatively correlated with kep_max, and kep_90.

CONCLUSION

PDZK1 is upregulated in HGG, predicts poor survival, and differentiates tumor grading in HGG patients. PDZK1 expression is correlated with DCE-MRI perfusion parameters.

Integration of Computational Pipeline to Streamline Efficacious Drug Nomination and Biomarker Discovery in Glioblastoma

Glioblastoma multiforme (GBM) is the deadliest, most heterogeneous, and most common brain cancer in adults. Not only is there an urgent need to identify efficacious therapeutics, but there is also a great need to pair these therapeutics with biomarkers that can help tailor treatment to the right patient populations. We built patient drug response models by integrating patient tumor transcriptome data with high-throughput cell line drug screening data as well as Bayesian networks to infer relationships between patient gene expression and drug response. Through these discovery pipelines, we identified agents of interest for GBM to be effective across five independent patient cohorts and in a mouse avatar model: among them are a number of MEK inhibitors (MEKis). We also predicted phosphoglycerate dehydrogenase enzyme (PHGDH) gene expression levels to be causally associated with MEKi efficacy, where knockdown of this gene increased tumor sensitivity to MEKi and overexpression led to MEKi resistance. Overall, our work demonstrated the power of integrating computational approaches. In doing so, we quickly nominated several drugs with varying known mechanisms of action that can efficaciously target GBM. By simultaneously identifying biomarkers with these drugs, we also provide tools to select the right patient populations for subsequent evaluation.

Effects of Tetrahydrolipstatin on Glioblastoma in Mice: MRI-Based Morphologic and Texture Analysis Correlated with Histopathology and Immunochemistry Findings-A Pilot Study

BACKGROUND

This study aimed to investigate the effects of tetrahydrolipstatin (orlistat) on heterotopic glioblastoma in mice by applying MRI and correlating the results with histopathology and immunochemistry.

METHODS

Human glioblastoma cells were injected subcutaneously into the groins of immunodeficient mice. After tumor growth of >150 mm3, the animals were assigned into a treatment group (n = 6), which received daily intraperitoneal injections of orlistat, and a control group (n = 7). MRI was performed at the time of randomization and before euthanizing the animals. Tumor volumes were calculated, and signal intensities were analyzed. The internal tumor structure was evaluated visually and with texture analysis. Western blotting and protein expression analysis were performed.

RESULTS

At histology, all tumors showed high mitotic and proliferative activity (Ki67 ≥ 10%). Reduced fatty acid synthetase expression was measured in the orlistat group (p < 0.05). Based on the results of morphologic MRI-based analysis, tumor growth remained concentric in the control group and changed to eccentric in the treatment group (p < 0.05). The largest area under the receiver operating curve of the predictors derived from the texture analysis of T2w images was for wavelet transform parameters WavEnHL_s3 and WavEnLH_s4 at 0.96 and 1.00, respectively.

CONCLUSIONS

Orlistat showed effects on heterotopically implanted glioblastoma multiforme in MRI studies of mice based on morphologic and texture analysis.

Haploinsufficiency of Adenomatous Polyposis Coli Coupled with Kirsten Rat Sarcoma Viral Oncogene Homologue Activation and P53 Loss Provokes High-Grade Glioblastoma Formation in Mice

Glioblastoma multiforme (GBM) is the most common and deadly type of brain tumor originating from glial cells. Despite decades of clinical trials and research, there has been limited success in improving survival rates. However, molecular pathology studies have provided a detailed understanding of the genetic alterations associated with the formation and progression of glioblastoma-such as Kirsten rat sarcoma viral oncogene homolog (KRAS) signaling activation (5%), P53 mutations (25%), and adenomatous polyposis coli (APC) alterations (2%)-laying the groundwork for further investigation into the biological and biochemical basis of this malignancy. These analyses have been crucial in revealing the sequential appearance of specific genetic lesions at distinct histopathological stages during the development of GBM. To further explore the pathogenesis and progression of glioblastoma, here, we developed the glial-fibrillary-acidic-protein (GFAP)-Cre-driven mouse model and demonstrated that activated KRAS and p53 deficiencies play distinct and cooperative roles in initiating glioma tumorigenesis. Additionally, the combination of APC haploinsufficiency with mutant Kras activation and p53 deletion resulted in the rapid progression of GBM, characterized by perivascular inflammation, large necrotic areas, and multinucleated giant cells. Consequently, our GBM models have proven to be invaluable resources for identifying early disease biomarkers in glioblastoma, as they closely mimic the human disease. The insights gained from these models may pave the way for potential advancements in the diagnosis and treatment of this challenging brain tumor.

Computed tomography scan radiation and brain cancer incidence

BACKGROUND

Computed tomography (CT) scans make substantial contributions to low-dose ionizing radiation exposures, raising concerns about excess cancers caused by diagnostic radiation.

METHODS

Deidentified medicare records for all Australians aged 0-19 years between 1985-2005 were linked to national death and cancer registrations to 2012. The National Cancer Institute CT program was used to estimate radiation doses to the brain from CT exposures in 1985-2005, Poisson regression was used to model the dependence of brain cancer incidence on brain radiation dose, which lagged by 2 years to minimize reverse causation bias.

RESULTS

Of 10 524 842 young Australians, 611 544 were CT-exposed before the age of 20 years, with a mean cumulative brain dose of 44 milligrays (mGy) at an average follow-up of 13.5 years after the 2-year lag period. 4472 were diagnosed with brain cancer, of whom only 237 had been CT-exposed. Brain cancer incidence increased with radiation dose to the brain, with an excess relative risk of 0.8 (95% CI 0.57-1.06) per 100 mGy. Approximately 6391 (95% CI 5255, 8155) persons would need to be exposed to cause 1 extra brain cancer.

CONCLUSIONS

For brain tumors that follow CT exposures in childhood by more than 2 years, we estimate that 40% (95% CI 29%-50%) are attributable to CT Radiation and not due to reverse causation. However, because of relatively low rates of CT exposure in Australia, only 3.7% (95% CI 2.3%-5.4%) of all brain cancers are attributable to CT scans. The population-attributable fraction will be greater in countries with higher rates of pediatric scanning.

Interstitial Photodynamic Therapy of Glioblastomas: A Long-Term Follow-up Analysis of Survival and Volumetric MRI Data

BACKGROUND

The treatment of glioblastomas, the most common primary malignant brain tumors, with a devastating survival perspective, remains a major challenge in medicine. Among the recently explored therapeutic approaches, 5-aminolevulinic acid (5-ALA)-mediated interstitial photodynamic therapy (iPDT) has shown promising results.

METHODS

A total of 16 patients suffering from de novo glioblastomas and undergoing iPDT as their primary treatment were retrospectively analyzed regarding survival and the characteristic tissue regions discernible in the MRI data before treatment and during follow-up. These regions were segmented at different stages and were analyzed, especially regarding their relation to survival.

RESULTS

In comparison to the reference cohorts treated with other therapies, the iPDT cohort showed a significantly prolonged progression-free survival (PFS) and overall survival (OS). A total of 10 of 16 patients experienced prolonged OS (≥ 24 months). The dominant prognosis-affecting factor was the MGMT promoter methylation status (methylated: median PFS of 35.7 months and median OS of 43.9 months) (unmethylated: median PFS of 8.3 months and median OS of 15.0 months) (combined: median PFS of 16.4 months and median OS of 28.0 months). Several parameters with a known prognostic relevance to survival after standard treatment were not found to be relevant to this iPDT cohort, such as the necrosis-tumor ratio, tumor volume, and posttreatment contrast enhancement. After iPDT, a characteristic structure (iPDT remnant) appeared in the MRI data in the former tumor area.

CONCLUSIONS

In this study, iPDT showed its potential as a treatment option for glioblastomas, with a large fraction of patients having prolonged OS. Parameters of prognostic relevance could be derived from the patient characteristics and MRI data, but they may partially need to be interpreted differently compared to the standard of care.

DNA5mC Regulator-Mediated Molecular Clusters and Tumor Microenvironment Signatures in Glioblastoma

Growing evidence links DNA methylation to tumor immunity. The impact of DNA methylation (5 mC) on the microenvironment surrounding tumors and immunotherapy remains to be clarified. Through clustering gene expression of 20 DNA methylation regulators, this study aimed at systematically analyzing DNA methylation regulator patterns and tumor microenvironment characteristics of TCGA-GBM patients. Various subtypes of glioblastoma exhibit different tumor microenvironments and DNA methylation patterns. Each DNA methylation modification was then assigned a DNA methylation score (DMS). High DMS was associated with a good prognosis. In contrast, the low DMS group had a relatively low survival rate. A correlation was also found between high DMS and enhanced immunotherapy efficacy in two immune checkpoint blocking treatment cohorts. To conclude, identifying DNA methylation regulation patterns may prove critical to understanding glioblastoma progression and differentiation, as well as future therapeutic targets.

An Approach to the Simultaneous Determination of a Panel of Five Biomarkers for the Early Detection of Brain Cancer Using the Stochastic Method

The simultaneous determination of heregulin-α and HER 1–4 plays an important role in brain cancer diagnosis and treatment. To date, only enzyme-linked immunosorbent assay (ELISA) or a semiquantitative colorimetric method have been used for the assay of these biomarkers; these methods are quite expensive and can only determine one biomarker in a run. Four 3D stochastic microsensors based on multi-walled carbon nanotubes enriched with gold nanoparticles and modified with inulin were designed for the simultaneous determination of heregulin-α and HER 1–4 in tumor brain tissue and whole blood samples. For the simultaneous measurement of HRG-α and HER 1–4, all sensors demonstrated low limits of determination (as fg mL−1 magnitude order), high sensitivities, and wide concentration ranges. From biological samples, high recovery values of more than 96% of analytes were obtained. The proposed sensor can detect HER 1–4 and heregulin-α in whole blood and tumor tissue samples at the same time.

Ferroptosis: A novel therapeutic strategy and mechanism of action in glioma

Glioma is the most common malignant tumor of the central nervous system and resistance is easily developed to chemotherapy drugs during the treatment process, resulting in high mortality and short survival in glioma patients. Novel therapeutic approaches are urgently needed to improve the therapeutic efficacy of chemotherapeutic drugs and to improve the prognosis of patients with glioma. Ferroptosis is a novel regulatory cell death mechanism that plays a key role in cancer, neurodegenerative diseases, and other diseases. Studies have found that ferroptosis-related regulators are closely related to the survival of patients with glioma, and induction of ferroptosis can improve glioma resistance to chemotherapy drugs. Therefore, induction of tumor cell ferroptosis may be an effective therapeutic strategy for glioma. This review summarizes the relevant mechanisms of ferroptosis, systematically summarizes the key role of ferroptosis in the treatment of glioma and outlines the relationship between ferroptosis-related ncRNAs and the progression of glioma.

An N-heterocyclic carbene iridium(III) complex as a potent anti-cancer stem cell therapeutic

Cancer stem cells (CSCs) represent a difficult to treat cellular niche within tumours due to their unique characteristics, which give them a high propensity for resistance to classical anti-cancer treatments and the ability to repopulate the tumour mass. An attribute that may be implicated in the high rates of recurrence of certain tumours. However, other characteristics specific to these cells, such as their high dependence on mitochondria, may be exploited for the development of new therapeutic agents that are effective against the niche. As such, a previously described phosphorescent N-heterocyclic carbene iridium(III) compound which showed a high level of cytotoxicity against classical tumour cell lines with mitochondria-specific effects was studied for its potential against CSCs. The results showed a significantly higher level of activity against several CSC lines compared to non-CSCs. Mitochondrial localisation and superoxide production were confirmed. Although the cell death involved caspase activation, their role in cell death was not definitive, with a potential implication of other, non-apoptotic pathways shown. A cytostatic effect of the compound was also displayed at low mortality doses. This study thus provides important insights into the mechanisms and the potential for this class of molecule in the domain of anti-CSC therapeutics.

SPTSSA Is a Prognostic Marker for Glioblastoma Associated with Tumor-Infiltrating Immune Cells and Oxidative Stress

Background. SPTSSA encodes the small subunit A of serine palmitoyltransferase. It catalyzes the formation of sphingoid long-chain base backbone of sphingolipids. Its role in glioma prognosis and tumor-infiltrating immune cells remains unclear. Methods. We analyzed SPTSSA expression and association with clinical prognosis using GEPIA and CGGA database. Then, GSEA was performed to identify relevant biological functions of SPTSSA. The correlations between SPTSSA expression and tumor immune infiltrates were investigated using CIBERSORT and TIMER. Finally, IHC and IF were performed to confirm the value of prognosis and the correlation with immune infiltration. Results. SPTSSA expression was significantly upregulated in diffuse glioma compared to normal tissues and associated with poor survival in GEPIA and CGGA database. Then, we identified biological processes and signaling pathways associated with SPTSSA expression. The result showed that SPTSSA enriched in the GO term like oxidative stress. Finally, we showed that SPTSSA expression was significantly associated with tumor-infiltrating immune cells and overall survival via IHC. Conclusion. These findings suggest that SPTSSA expression might be used as a prognostic biomarker for glioma and potential target for novel glioma therapy.

Effects of two types of exercise training on psychological well-being, sleep and physical fitness in patients with high-grade glioma (WHO III and IV)

BACKGROUND

There is evidence that regular exercise training has the potential to improve psychological well-being among cancer survivors. However, limited findings are available for individuals with high-grade glioma (HGG; WHO grade III and IV) after neurosurgery and undergoing radiochemotherapy. Given this, endurance and strengths training were employed to investigate their impact on symptoms of depression, feelings of stress and anxiety, fatigue, insomnia, and physical fitness, compared to an active control condition.

METHODS

A total of 29 patients (M = 52.07, SD = 12.45, 55.2% women) participated in this randomized controlled trial (RCT). After neurosurgical treatment and during adjuvant radiotherapy and chemotherapy or combined radiochemotherapy, patients were randomly assigned to the following conditions: Endurance training (n = 10); strengths training (n = 11); active control condition (n = 8). At baseline, three weeks and six weeks later at the end of the study physical fitness was objectively measured with a 6-min walk test (6MWT) and a handgrip test. Participants completed a series of questionnaires covering sociodemographic information, symptoms of depression, stress, anxiety, fatigue, and insomnia. Further, experts rated participants' severity of symptoms of depression.

RESULTS

Over time and compared to the strengths and active control condition, self-rated symptoms of depression, state and trait anxiety, stress and insomnia decreased in the endurance condition. Over time and compared to the endurance and active control condition, no changes on symptoms of depression, anxiety, stress, or insomnia were observed in the strengths condition. Over time and compared to the endurance and strengths condition, symptoms of depression (self-ratings), stress, insomnia and fatigue decreased in the active control condition. Fatigue increased in both exercising conditions. Over time and irrespective from the study condition, physical fitness did neither improve nor decrease.

CONCLUSIONS

The pattern of results suggests that endurance training and an active control condition improved dimensions of depression, stress, and anxiety, while mere strengths training appeared to neither improve, nor decrease dimensions of psychological functioning. Further, exercise interventions did not change physical fitness, but increased fatigue. Overall, endurance training and an active control condition appeared to favorably impact on psychological well-being among patients with high-grade glioma after neurosurgery and undergoing radiochemotherapy.

Downregulation of GPR160 inhibits the progression of glioma through suppressing epithelial to mesenchymal transition (EMT) biomarkers

BACKGROUND

Glioblastoma multiforme (GBM) is one of the most fatal types of malignant tumors, the cause of which is mostly unknown. Orphan GPCRs (GPRs) have been previously implicated in tumor growth and metastasis. Therefore, these GPRs could prove to be alternative and promising therapeutic targets for cancer treatment.

OBJECTIVE

The role of GPR160 in GBM has not yet been assessed. This study aims to explore the association of GPR160 with glioma progression and investigate its role in epithelial-to-mesenchymal transition (EMT) and metastasis.

METHODS

Changes in protein expression were assessed using western blot analysis and immunofluorescent staining assays, while mRNA expression changes were evaluated using qRT-PCR. To detect the changes in progression and metastasis, MTT, EdU proliferation, wound healing, transwell migration, and flow cytometry assays were carried out in vitro. An epithelial to mesenchymal phenotypic analysis was performed to detect EMT.

RESULTS

We demonstrated that knockdown of GPR160 inhibited proliferation, colony formation, and cell viability and promoted apoptosis. Pro-apoptotic biomarkers were upregulated, while anti-apoptotic biomarkers were downregulated. Cell lines with GPR160 knockdown (GPR160 KD) showed a slowed migration rate and decreased invasion ability. EMT mesenchymal biomarkers were downregulated in GPR160 KD cell lines, while epithelial biomarkers were upregulated.

CONCLUSION

This study provides evidence that GPR160 is a potential therapeutic target in GBM for the first time. These findings can be used to discover in detail the molecular mechanism and pathways through which GPR160 promotes glioma progression.

Nuclear medicine and radiotherapy in the clinical management of glioblastoma patients

Introduction

The aim of the narrative review was to analyse the applications of nuclear medicine (NM) techniques such as PET/CT with different tracers in combination with radiotherapy for the clinical management of glioblastoma patients.

Materials and methods

Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used.

Results

This paper contains a narrative report and a critical discussion of NM approaches in combination with radiotherapy in glioma patients.

Conclusions

NM can provide the Radiation Oncologist several aids that can be useful in the clinical management of glioblastoma patients. At the same, these results need to be validated in prospective and multicenter trials.

The Subventricular Zone in Glioblastoma: Genesis, Maintenance, and Modeling

Glioblastoma (GBM) is a malignant tumor with a median survival rate of 15-16 months with standard care; however, cases of successful treatment offer hope that an enhanced understanding of the pathology will improve the prognosis. The cell of origin in GBM remains controversial. Recent evidence has implicated stem cells as cells of origin in many cancers. Neural stem/precursor cells (NSCs) are being evaluated as potential initiators of GBM tumorigenesis. The NSCs in the subventricular zone (SVZ) have demonstrated similar molecular profiles and share several distinctive characteristics to proliferative glioblastoma stem cells (GSCs) in GBM. Genomic and proteomic studies comparing the SVZ and GBM support the hypothesis that the tumor cells and SVZ cells are related. Animal models corroborate this connection, demonstrating migratory patterns from the SVZ to the tumor. Along with laboratory and animal research, clinical studies have demonstrated improved progression-free survival in patients with GBM after radiation to the ipsilateral SVZ. Additionally, key genetic mutations in GBM for the most part carry regulatory roles in the SVZ as well. An exciting avenue towards SVZ modeling and determining its role in gliomagenesis in the human context is human brain organoids. Here we comprehensively discuss and review the role of the SVZ in GBM genesis, maintenance, and modeling.

Combined Diagnostic Accuracy of Diffusion and Perfusion MR Imaging to Differentiate Radiation-Induced Necrosis from Recurrence in Glioblastoma

We aimed to use quantitative values derived from perfusion and diffusion-weighted MR imaging (PWI and DWI) to differentiate radiation-induced necrosis (RIN) from tumor recurrence in Glioblastoma (GBM) and investigate the best parameters for improved diagnostic accuracy and clinical decision-making. Methods: A retrospective analysis of follow-up MRI with new enhancing observations was performed in histopathologically confirmed subjects of post-treated GBM, who underwent re-surgical exploration. Quantitative estimation of rCBV (relative cerebral blood volume) from PWI and three methods of apparent diffusion coefficient (ADC) estimation were performed, namely ADC R1 (whole cross-sectional area of tumor), ADC R2 (only solid enhancing lesion), and ADC R3 (central necrosis). ROC curve and logistic regression analysis was completed. A confusion matrix table created using Excel provided the best combination parameters to ameliorate false-positive and false-negative results. Results: Forty-four subjects with a mean age of 46 years (range, 19−70 years) underwent re-surgical exploration with RIN in 28 (67%) and recurrent tumor in 16 (33%) on histopathology. rCBV threshold of >3.4 had the best diagnostic accuracy (AUC = 0.93, 81% sensitivity and 89% specificity). A multiple logistic regression model showed significant contributions from rCBV (p < 0.001) and ADC R3 (p = 0.001). After analysis of confusion matrix ADC R3 > 2032 × 10−6 mm2 achieved 100% specificity with gain in sensitivity (94% vs. 56%). Conclusions: A combination of parameters had better diagnostic performance, and a stepwise combination of rCBV and ADC R3 obviated unnecessary biopsies in 10% (3/28), leading to improved clinical decision-making.

Identification of Ferroptosis-Related Biomarkers for Prognosis and Immunotherapy in Patients With Glioma

Ferroptosis is a novel type of iron- and ROS-dependent cell death and is involved in various diseases. LncRNAs are involved and play important roles in the occurrence and development of several cancers. However, researches about the role of ferroptosis-related lncRNAs in glioma are relatively rare. Here, we identified nine ferroptosis-related lncRNAs and then constructed a prognostic model by the LASSO and Cox analysis. The model could predict overall survival with high sensitivity and specificity according to ROC curves. In addition, the cell cycle, p53 signaling, apoptosis, and oxidative phosphorylation pathways were obviously enriched in the pathogenesis of glioma by gene set enrichment analysis. A nomogram was constructed by integrating several independent prognostic clinicopathological features, and it could provide a valuable predictive tool for overall survival. Furthermore, a strong correlation between these nine lncRNAs and immunotherapy was found. Glioma patients in the high-risk group had higher TMB using somatic mutation data, different immune infiltration, and higher expression of immune checkpoints, indicating these patients might benefit from immune checkpoint inhibitor therapy. In summary, these nine ferroptosis-related lncRNAs were promising biomarkers for predicting overall survival and guiding immunotherapy or future immune checkpoint inhibitor development for glioma patients.

miR-221/222 suppression induced by activation of the cAMP/PKA/CREB1 pathway is required for cAMP-induced bidirectional differentiation of glioma cells

Factors that increase cAMP levels can induce lineage-specific differentiation of glioma cells into astrocyte-like cells. However, the differentiation pattern and underlying mechanisms remain unclear. Here, we find that cAMP/protein kinase A (PKA)/cAMP responsive element binding protein 1 (CREB1)-induced miR-221/222 suppression contributes to the neuron-like differentiation of gliomas. cAMP agonists selectively induced neuron- and astrocyte-like but not oligodendrocyte-like differentiation of C6 glioma cells. PKA inhibitors and CREB1 knockout blocked neuron-like differentiation of glioma cells. cAMP inhibited miR-221/222 in a PKA/CREB1-dependent manner. Importantly, both in vitro and in vivo assays demonstrated that transcriptional suppression of miR-221/222 is required for neuronal differentiation of glioma cells. Our findings suggest that increasing cAMP levels can induce bidirectional differentiation of glioma cells. Furthermore, the miR-221/222 cluster acts as an epigenetic brake during glioma differentiation.

Challenges and Prospects for Designer T and NK Cells in Glioblastoma Immunotherapy

Glioblastoma (GBM) is the most prevalent, aggressive primary brain tumour with a dismal prognosis. Treatment at diagnosis has limited efficacy and there is no standardised treatment at recurrence. New, personalised treatment options are under investigation, although challenges persist for heterogenous tumours such as GBM. Gene editing technologies are a game changer, enabling design of novel molecular-immunological treatments to be used in combination with chemoradiation, to achieve long lasting survival benefits for patients. Here, we review the literature on how cutting-edge molecular gene editing technologies can be applied to known and emerging tumour-associated antigens to enhance chimeric antigen receptor T and NK cell therapies for GBM. A tight balance of limiting neurotoxicity, avoiding tumour antigen loss and therapy resistance, while simultaneously promoting long-term persistence of the adoptively transferred cells must be maintained to significantly improve patient survival. We discuss the opportunities and challenges posed by the brain contexture to the administration of the treatments and achieving sustained clinical responses.

18F-FET-PET-guided gross total resection improves overall survival in patients with WHO grade III/IV glioma: moving towards a multimodal imaging-guided resection

Purpose

PET using radiolabeled amino acid [¹⁸F]-fluoro-ethyl-_L-tyrosine (FET-PET) is a well-established imaging modality for glioma diagnostics. The biological tumor volume (BTV) as depicted by FET-PET often differs in volume and location from tumor volume of contrast enhancement (CE) in MRI. Our aim was to investigate whether a gross total resection of BTVs defined as < 1 cm³ of residual BTV (PET GTR) correlates with better oncological outcome.

Methods

We retrospectively analyzed imaging and survival data from patients with primary and recurrent WHO grade III or IV gliomas who underwent FET-PET before surgical resection. Tumor overlap between FET-PET and CE was evaluated. Completeness of FET-PET resection (PET GTR) was calculated after superimposition and semi-automated segmentation of pre-operative FET-PET and postoperative MRI imaging. Survival analysis was performed using the Kaplan–Meier method and the log-rank test.

Results

From 30 included patients, PET GTR was achieved in 20 patients. Patients with PET GTR showed improved median OS with 19.3 compared to 13.7 months for patients with residual FET uptake (p = 0.007; HR 0.3; 95% CI 0.12–0.76). This finding remained as independent prognostic factor after performing multivariate analysis (HR 0.19, 95% CI 0.06–0.62, p = 0.006). Other survival influencing factors such as age, IDH-mutation, MGMT promotor status, and adjuvant treatment modalities were equally distributed between both groups.

Conclusion

Our results suggest that PET GTR improves the OS in patients with WHO grade III or IV gliomas. A multimodal imaging approach including FET-PET for surgical planning in newly diagnosed and recurrent tumors may improve the oncological outcome in glioma patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11060-021-03844-1.

DNA Methylation-based Diagnostic and Prognostic Biomarkers for Glioblastoma

Glioblastomas are the most common primary central nervous system malignancy tumor in adults. Glioblastoma patients have poor prognosis, with an average survival period of approximately 14 mo after diagnosis. To date, there are a limited number of effective treatment methods for glioblastoma, and its molecular mechanisms remain elusive. In this article, we analyzed the key biomarkers and pathways in glioblastoma patients based on gene expression and DNA methylation datasets. The 60 hypomethylated/upregulated genes and 110 hypermethylated/downregulated genes were identified in GSE50923, GSE50161, and GSE116520 microarrays. Functional enrichment analyses indicated that these methylated-differentially expressed genes were primarily involved in collagen fibril organization, chemical synaptic transmission, extracellular matrix-receptor interaction, and GABAergic synapse. The hub genes were screened from a protein–protein interaction network; in selected genes, increased NMB mRNA level was associated with favorable overall survival, while elevated CHI3L1, POSTN, S100A4, LOX, S100A11, IGFBP2, SLC12A5, VSNL1, and RGS4 mRNA levels were associated with poor overall survival in glioblastoma patients. Additionally, CHI3L1, S100A4, LOX, and S100A11 expressions were negatively correlated with their corresponding methylation status. Furthermore, the receiver-operator characteristic curve analysis indicated that CHI3L1, S100A4, LOX, and S100A11 can also serve as highly specific and sensitive diagnostic biomarkers for glioblastoma patients. Collectively, our study revealed the possible methylated-differentially expressed genes and associated pathways in glioblastoma and identified four DNA methylation-based biomarkers of glioblastoma. These results may provide insight on diagnostic and prognostic biomarkers, and therapeutic targets in glioblastoma.

Glioblastoma in adolescents and young adults: An age-based comparative study from Jordan over a 17-year period

BACKGROUND

Glioblastoma (GBM) is the most common primary brain tumor. Epidemiologic studies on GBM are rarely reported in the special age group of adolescents and young adults (AYA) in comparison to other age groups. We aim to present data on GBM in Jordan, with a focus on the AYA age, including the incidence, gender, location and outcome, as well as long term survival (LTS).

METHODS

Data on GBM was requested from the Jordan Cancer Registry (JCR), and statistical analysis was performed. All data were retrospective and anonymized.

RESULTS

Eight hundred GBM cases were analyzed from 2000 to 2016 including 505 males (63.1 %). Males outnumbered females across are studied years (p-value <0.001). There were 49 pediatrics (0-14 years, 6.1 %), 125 AYA (15-39 years, 15.6 %), 358 adults (40-59 years, 44.8 %) and 268 elderly (60+ years, 33.5 %) cases. Supratentorial location predominated across all age groups (p-value <0.001). The preponderance of males and supratentorial tumors remained across the AYA age group in comparison to others. The median overall survival (OS) was 23.61 months. AYA age group had a better outcome in comparison to the adults/elderly age group (p-value< 0.001). LTS appear to be more common in the AYA age group (p-value 0.021).

CONCLUSIONS

This is the first comparative epidemiologic study of GBM in Jordan, focusing on the AYA age group. The AYA age group appears to be associated with a better outcome compared to older age groups, with more LTS compared to others.

A Novel Deep Learning Method for Recognition and Classification of Brain Tumors from MRI Images

A brain tumor is an abnormal growth in brain cells that causes damage to various blood vessels and nerves in the human body. An earlier and accurate diagnosis of the brain tumor is of foremost important to avoid future complications. Precise segmentation of brain tumors provides a basis for surgical planning and treatment to doctors. Manual detection using MRI images is computationally complex in cases where the survival of the patient is dependent on timely treatment, and the performance relies on domain expertise. Therefore, computerized detection of tumors is still a challenging task due to significant variations in their location and structure, i.e., irregular shapes and ambiguous boundaries. In this study, we propose a custom Mask Region-based Convolution neural network (Mask RCNN) with a densenet-41 backbone architecture that is trained via transfer learning for precise classification and segmentation of brain tumors. Our method is evaluated on two different benchmark datasets using various quantitative measures. Comparative results show that the custom Mask-RCNN can more precisely detect tumor locations using bounding boxes and return segmentation masks to provide exact tumor regions. Our proposed model achieved an accuracy of 96.3% and 98.34% for segmentation and classification respectively, demonstrating enhanced robustness compared to state-of-the-art approaches.

3D stochastic microsensors for molecular recognition and determination of heregulin-α in biological samples

Two 3D stochastic microsensors based on single and multi-walled carbon nanotubes modified with 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine manganese (III) chloride were proposed for the molecular recognition and determination of heregulin-α, in whole blood samples and tumour brain tissues. The proposed 3D stochastic sensors had limits of determinations of 102 fg mL^-1 and high sensitivities. The linear concentration ranges of the two 3D stochastic microsensors covered the healthy people as well as the patients confirmed with brain cancer. Determination of heregulin-α was done in whole blood and tissue samples using the screening method based on the proposed 3D stochastic microsensors as well as using the ELISA method; very good correlations were obtained between the two methods proving that the proposed method can be used in screening tests of whole blood and tumoural tissue samples for molecular recognition and determination of heregulin-α.

CircSKA3 Downregulates miR-1 Through Methylation in Glioblastoma to Promote Cancer Cell Proliferation

Background

Circular RNA circSKA3 plays an oncogenic role in breast cancer, while its role in glioblastoma (GBM) is unknown. This study aimed to explore the role of circSKA3 in GBM.

Methods

Differential expression of circSKA3 and miR-1 in GBM and adjacent non-cancer tissue samples were analyzed by RT-qPCR. GBM cells were transfected with circSKA3 expression vector or miR-1 mimic, followed by RT-qPCR to explore the potential crosstalk between them. Methylation-specific PCR (MSP) was carried out to assess the role of circSKA3 in regulating the methylation of miR-1 gene. The role of circSKA3 and miR-1 in regulating GBM cell proliferation was analyzed by CCK-8 assay.

Results

We found that circSKA3 was upregulated in GBM and inversely correlated with miR-1 across GBM tissues. High expression levels of circSKA3 and low expression levels of miR-1 were significantly correlated with the poor survival of GBM patients. In GBM cells, overexpression of circSKA3 increased the methylation of miR-1 gene and decreased the expression of miR-1. CCK-8 assay showed that overexpression of circSKA3 reduced the inhibitory effects of miR-1 on cell proliferation.

Conclusion

Therefore, circSKA3 may downregulate miR-1 through methylation in GBM to promote cancer cell proliferation.

Prognostic factors in patients with glioblastoma multiforme: focus on the pathologic variants

The aim of this study was to offer predicting factors for survival in adult patients with glioblastoma multiforme. 153 consecutive patients with high-grade glioma (WHO grade IV) were studied in Imam Reza hospital, Kermanshah University of Medical Science, Kermanshah, Iran, between April 2003 and April 2017. All patients treated with surgical resection and standard postoperative radiotherapy (54 Gy). Using the patients' charts and electronic medical records system, the following data were obtained: gender, age, Karnofsky performance status (KPS) score on admission, primary vs. secondary type, extent of surgery, tumor location, tumor size, necrosis size, use of Temozolomide (TMZ), pathology subtype, and immunohistochemistry results. Patients were followed from the time of the surgery until the death occurred. Overall survival (OS) and progression-free survival (PFS) were calculated by the Kaplan-Meier method. Survival time curves for various subgroups were compared by the log-rank test. The impact of the suggested prognostic factors on survival was evaluated by univariate and multivariate analyses. Age, gender, KPS, extent of surgery, tumor location, necrosis size, and reoperation in recurrence had not any statistically significant effect on survival. Univariate analysis revealed a significant impact on outcome for pathology subtype (PFS: P < 0.001, OS: P < 0.001), tumor type (primary vs. secondary) (PFS: P = P < 0.001, OS: P < 0.001), tumor size (PFS: P = 0.044, OS: P = 0.04), TMZ therapy (PFS: P < 0.001, OS: P < 0.001), P53 (PFS: P < 0.001, OS: P < 0.001), and Ki67 (PFS: P < 0.001, OS: P < 0.001). In multivariate analysis, independent favorable prognostic factors for survival were pathology subtype (PFS: P < 0.001, OS: P < 0.001), type (PFS: P < 0.001, OS: 0.012), TMZ (PFS: P < 0.001, OS: P < 0.001), P53 (PFS: P < 0.001, OS: P < 0.001), and Ki67 (PFS: P < 0.001, OS: P < 0.001). The results suggest that pathology subtype, primary vs. secondary type, TMZ therapy, P53, and Ki 63 may play an important role in the survival of patients with glioblastoma multiforme. There is no relationship detected between age, gender, KPS, tumor size and location, necrosis size, extent of surgery, reoperation in recurrence, and patient survival.

Surviving glioblastoma and a sense of disconnection

Given the poor prognosis of glioblastoma, little focus has been placed on the needs of long-term survivors (those alive at least two years following diagnosis). The aim of this project was to explore the lived experience of long-term survivors of glioblastoma using a qualitative approach. Long-term survivors of glioblastoma diagnosed between 1/1/2006-31/12/2016 were identified at the tertiary centre involved. Participants underwent a semi-structured qualitative interview and caregiver dyads were collected if available. Thematic analysis was undertaken where themes were gradually generated from the data alongside data collection and confirmed or contrasted as data collection proceeded. Participants were selected and interviewed until data saturation was reached at 10 interviews. The overarching theme explaining the data was a sense of disconnection, beginning with the shock of diagnosis, and evolving over time, leading survivors to feel disconnected from (1) 'who I was', redefining their work, independence and social self; (2) 'who I am', contributing to social isolation, disavowal, and anxiety and depression; and (3) 'who I could be', reassessing their future. This unique study highlights the acute emotional distress and disconnection that begins with diagnosis and its evolving impact on the lived experience. Clinicians need to consider the emotional impact of survival when managing these patients and adopt a holistic approach, including the early introduction of psychosocial support to patients and their caregivers. Further validation of these findings in a larger cohort is desirable.

Clinical characterization of glioblastoma patients living longer than 2 years: A retrospective analysis of two Italian institutions

AIM

Despite the advances in surgery and radio-chemotherapy, the prognosis of glioblastoma (GBM) remains poor with about 13% of patients alive at 24 months.

METHODS

A total of 75 long-term survivors (LTS), defined as alive at least 24 months from diagnosis, were retrospectively analyzed. Overall survival (OS) and recurrence-free-survival (RFS) were calculated and related to patient characteristics and treatment received.

RESULTS

Median age and Karnofsky performance status (KPS) were 56 years and 100%, respectively. After surgery (gross tumor resection-GTR in 62, 83% patients), all LTS received concomitant temozolomide (TMZ) with radiotherapy and 70 (93%) adjuvant TMZ. Of these, 10 (13%) discontinued TMZ prior the completion of 6 cycles, 37 (49%) received 6 cycles and 23 (31%) >6 cycles. Sixty-nine (92%) patients experienced a first tumor recurrence at a median time of 21 months. Of these, 32 (46%) were submitted to a second surgery, 34 (49%) to other no-surgical treatments and 3 (5%) only supportive care. At multivariate analysis, OS was significantly improved by second surgery after first recurrence (P = 0.0032) and by cycles of adjuvant TMZ > 6 versus ≤6 (P = 0.05). More than six cycles of TMZ significantly conditioned also first RFS (P = 0.011) and second RFS (P = 0.033).

CONCLUSION

The large majority of LTS had <65 years, had a high KPS and received GTR. OS and RFS resulted significantly related to an extended administration of adjuvant TMZ (>6 cycles) and a second surgery in case of recurrence.

Advances and trends of hydrogel therapy platform in localized tumor treatment: A review

Due to limitations of treatment and the stubbornness of infiltrative tumor cells, the outcome of conventional antitumor treatment is often compromised by a variety of factors, including severe side effects, unexpected recurrence, and massive tissue loss during the treatment. Hydrogel-based therapy is becoming a promising option of cancer treatment, because of its controllability, biocompatibility, high drug loading, prolonged drug release, and specific stimuli-sensitivity. Hydrogel-based therapy has good malleability and can reach some areas that cannot be easily touched by surgeons. Furthermore, hydrogel can be used not only as a carrier for tumor treatment agents, but also as a scaffold for tissue repair. In this review, we presented the latest researches in hydrogel applications of localized tumor therapy and highlighted the recent progress of hydrogel-based therapy in preventing postoperative tumor recurrence and improving tissue repair, thus proposing a new trend of hydrogel-based technology in localized tumor therapy. And this review aims to provide a novel reference and inspire thoughts for a more accurate and individualized cancer treatment.

LncRNA DCST1-AS1 downregulates miR-29b through methylation in glioblastoma (GBM) to promote cancer cell proliferation

INTRODUCTION

The role of DCST1-AS1 has been investigated in several types of cancer, while the role of DCST1-AS1 in glioblastoma (GBM) is unclear. This study aimed to investigate the role of DCST1-AS1 in GBM.

METHODS

GBM and paired non-tumor tissues were collected from 62 GBM patients. Expression levels of DCST1-AS1 and miR-29b in paired tissue samples were determined by RT-qPCR. The role of DCST1-AS1 in regulating the methylation of miR-29b was assessed by methylation-specific PCR (MSP). Cell proliferation was analyzed by cell proliferation assay.

RESULTS

It was observed that the upregulation of DCST1-AS1 in GBM predicted poor survival. MiR-29b was downregulated in GBM and inversely correlated with the expression of DCST1-AS1. In GBM cells, overexpression of DCST1-AS1 resulted in the downregulation of miR-29b and the increased methylation level of miR-29b gene. Overexpression of DCST1-AS1 resulted in increased cell proliferation. Moreover, Overexpression of DCST1-AS1 significantly reversed the inhibitory effects of miR-29b on cancer cell proliferation.

CONCLUSION

DCST1-AS1 may downregulate miR-29b through methylation in GBM to promote cancer cell proliferation.

Glioblastoma multiforme that unusually present with radiographic dural tails: Questioning the diagnostic paradigm with a rare case report

Glioblastoma multiforme (GBM) is both the most common as well as one of the most aggressive primary intracerebral tumors. It classically presents on magnetic resonance imaging as a heterogeneous ring-enhancing lesion in the brain parenchyma with central necrosis. This type of neoplasm can also rarely present, however, as a mass with meningeal attachment and radiographic evidence of a dural tail, which was until recently thought to be specific to meningiomas. Here we present a case of a central nervous system neoplasm that on imaging was initially suggestive of meningioma based on its presence of a dural tail. Final pathology, however, revealed desmoplastic GBM. It is, therefore, important to include GBM on the differential diagnosis of a patient presenting with a dural-based lesion on imaging, especially since the overall survival rate of GBM is much worse than that of a suspected meningioma.

Spider venom administration impairs glioblastoma growth and modulates immune response in a non-clinical model

Molecules from animal venoms are promising candidates for the development of new drugs. Previous in vitro studies have shown that the venom of the spider Phoneutria nigriventer (PnV) is a potential source of antineoplastic components with activity in glioblastoma (GB) cell lines. In the present work, the effects of PnV on tumor development were established in vivo using a xenogeneic model. Human GB (NG97, the most responsive line in the previous study) cells were inoculated (s.c.) on the back of RAG^−/− mice. PnV (100 µg/Kg) was administrated every 48 h (i.p.) for 14 days and several endpoints were evaluated: tumor growth and metabolism (by microPET/CT, using ¹⁸F-FDG), tumor weight and volume, histopathology, blood analysis, percentage and profile of macrophages, neutrophils and NK cells isolated from the spleen (by flow cytometry) and the presence of macrophages (Iba-1 positive) within/surrounding the tumor. The effect of venom was also evaluated on macrophages in vitro. Tumors from PnV-treated animals were smaller and did not uptake detectable amounts of ¹⁸F-FDG, compared to control (untreated). PnV-tumor was necrotic, lacking the histopathological characteristics typical of GB. Since in classic chemotherapies it is observed a decrease in immune response, methotrexate (MTX) was used only to compare the PnV effects on innate immune cells with a highly immunosuppressive antineoplastic drug. The venom increased monocytes, neutrophils and NK cells, and this effect was the opposite of that observed in the animals treated with MTX. PnV increased the number of macrophages in the tumor, while did not increase in the spleen, suggesting that PnV-activated macrophages were led preferentially to the tumor. Macrophages were activated in vitro by the venom, becoming more phagocytic; these results confirm that this cell is a target of PnV components. Spleen and in vitro PnV-activated macrophages were different of M1, since they did not produce pro- and anti-inflammatory cytokines. Studies in progress are selecting the venom molecules with antitumor and immunomodulatory effects and trying to better understand their mechanisms. The identification, optimization and synthesis of antineoplastic drugs from PnV molecules may lead to a new multitarget chemotherapy. Glioblastoma is associated with high morbidity and mortality; therefore, research to develop new treatments has great social relevance. Natural products and their derivatives represent over one-third of all new molecular entities approved by FDA. However, arthropod venoms are underexploited, although they are a rich source of new molecules. A recent in vitro screening of the Phoneutria nigriventer spider venom (PnV) antitumor effects by our group has shown that the venom significantly affected glioblastoma cell lines. Therefore, it would be relevant to establish the effects of PnV on tumor development in vivo, considering the complex neoplastic microenvironment. The venom was effective at impairing tumor development in murine xenogeneic model, activating the innate immune response and increasing tumor infiltrating macrophages. In addition, PnV activated macrophages in vitro for a different profile of M1. These activated PnV-macrophages have potential to fight the tumor without promoting tumorigenesis. Studies in progress are selecting the venom molecules with antitumor and immunomodulatory effects and trying to better understand their mechanisms. We aim to synthesize and carry out a formulation with these antineoplastic molecules for clinical trials. Spider venom biomolecules induced smaller and necrotic xenogeneic GB; spider venom activated the innate immune system; venom increased blood monocytes and the migration of macrophages to the tumor; activated PnV-macrophages have a profile different of M1 and have a potential to fight the tumor without promote tumorigenesis.

On PTV definition for glioblastoma based on fiber tracking of diffusion tensor imaging data

Radiotherapy (RT) is commonly applied for the treatment of glioblastoma multiforme (GBM). Following the planning target volume (PTV) definition procedure standardized in guidelines, a 20% risk of missing non-local recurrences is present. Purpose of this study was to evaluate whether diffusion tensor imaging (DTI)-based fiber tracking may be beneficial for PTV definition taking into account the prediction of distant recurrences. 56 GBM patients were examined with magnetic resonance imaging (MRI) including DTI performed before RT after resection of the primary tumor. Follow-up MRIs were acquired in three month intervals. For the seven patients with a distant recurrence, fiber tracking was performed with three algorithms and it was evaluated whether connections existed from the primary tumor region to the distant recurrence. It depended strongly on the used tracking algorithm and the used tracking parameters whether a connection was observed. Most of the connections were weak and thus not usable for PTV definition. Only in one of the seven patients with a recurring tumor, a clear connection was present. It seems unlikely that DTI-based fiber tracking can be beneficial for predicting distant recurrences in the planning of PTVs for glioblastoma multiforme.

Overexpression of Tripartite Motif-Containing 48 (TRIM48) Inhibits Growth of Human Glioblastoma Cells by Suppressing Extracellular Signal Regulated Kinase 1/2 (ERK1/2) Pathway

BACKGROUND Herein, we found that tripartite motif-containing 48 (TRIM48) was reduced in human glioblastoma (GBM) cell lines. We investigated whether and how TRIM48 functions in human GBM in vitro. MATERIAL AND METHODS Human GBM cells (U87 MG and U138 MG) were infected with lentivirus to overexpress TRIM48, and 1 human GBM cell line (T98G) was infected with siRNAs to knock down TRIM48 expression. Techniques used included cell proliferation assay, measured by CCK-8 and BrdU-ELISA method, and cell cycle assay, determined using flow cytometry. Curcumin, a specific activator of extracellular signal regulated kinases (ERK1/2), or PD98059, a specific inhibitor of ERK1/2, was used to activate or block the ERK1/2 pathway, respectively. Expression of phosphorylated (p)-ERK1/2, and its downstream targets (Cyclin D1) were measured to assess the mechanism. RESULTS Our data suggest that overexpression of TRIM48 reduces the viability of U87 MG and U138 MG and leads to cell cycle arrest (in G0-G1 phase), which is associated with blockade of the ERK1/2 pathway and reduction of Cyclin D1. In contrast, knockdown of TRIM48 resulted in the opposite effects. Interestingly, the inhibitory effect of TRIM48 overexpression on human GBM cell growth and the inactivation of ERK1/2 were significantly alleviated with additional curcumin treatment, while it the promoted the effect of siTRIM48 on human GBM cell growth, and the activation of ERK1/2 was significantly alleviated with additional PD98059 treatment. CONCLUSIONS TRIM48 suppressed the growth of human GBM cell via the prevention of ERK1/2 activation.

Over ten years overall survival in glioblastoma: A different disease?

PURPOSE

The reasons why a specific subset of glioblastoma (GBM) patients survive longer than others is still unclear. This study analyzed a cohort of long-term and very-long-term GBM survivors to determine which genetic alterations or patient's characteristics influence survival time.

METHODS

We retrospectively reviewed a cohort of GBM patients treated at our institution over the last 20 years, stratifying patients in three groups: those with a survival time ≥ 36 months and < 120 months (LTS), ≥120 months (VLTS), and < 36 months, respectively. Clinical (age, sex, focality, resection degree, Karnofsky performance status), and immunohistochemical and molecular data (Ki-67 expression and multiple genes alterations) were collected. We then utilized principal component analysis, logistic regression, and Cox proportional hazard models to identify those variables associated with survival.

RESULTS

Younger age at presentation (HR = 0.36, 95% CI 0.21-0.67, p = .001), and MGMT promoter [(MGMTp), methylated, HR = 0.57, CI 0.34-0.96, p = .034) were associated with higher odds of VLTS survival. The multivariate analysis showed how the combination of younger age (< 50 years), Ki-67 < 10%, and the coexistence of TERTp not mutated, MGMTp methylated, and IDH1/2 mutated in the same patient are also associated with higher odds of survival (HR = 0.10, CI 0.01-0.74, p = .025).

CONCLUSIONS

We confirmed younger age at presentation and MGMTp methylation as the only independent factors associated with VLTS. The exceptional survival of our VLTS patients is probably associated with different, still understudied, gene mutations, or with the coexistence of multiple factors.

Returning to work after multimodal treatment in glioblastoma patients

OBJECTIVE Although multimodal treatment for glioblastoma (GBM) has resulted in longer survival, uncertainties exist regarding health-related quality of life and functional performance. Employment represents a useful functional end point and an indicator of social reintegration. The authors evaluated the rate of patients resuming their employment and the factors related to work capacity. METHODS The authors performed a retrospective study of working-age patients treated with surgery and radiochemotherapy between 2012 and 2015. Data were collected before and after surgery and at 6, 12, 18, and 24 months. Employment was categorized according to the French Socio-Professional Groups and analyzed regarding demographic and clinical data, performance status, socio-professional category, radiological features, type, and quality of resection. RESULTS A total of 125 patients, mean age 48.2 years, were identified. The mean follow-up was 20.7 months with a median survival of 22.9 months. Overall, 21 patients (18.3%) went back to work, most on a part-time basis (61.9%). Of the patients who were alive at 6, 12, 18, and 24 months after diagnosis, 8.7%, 13.8%, 15.3%, and 28.2%, respectively, were working. Patients going back to work were younger (p = 0.03), had fewer comorbidities (p = 0.02), and had a different distribution of socio-professional groups, with more patients belonging to higher occupation categories (p = 0.02). Treatment-related symptoms (36.2%) represented one of the main factors that prevented the resumption of work. Employment was strongly associated with performance status (p = 0.002) as well as gross-total removal (p = 0.04). No statistically significant difference was found regarding radiological or molecular features and the occurrence of complications after surgery. CONCLUSIONS GBM diagnosis and treatment has a significant socio-professional impact with only a minority of patients resuming work, mostly on a part-time basis.

Trace Element Concentration Changes in Brain Tumors: A Review

Trace elements have been implicated in cancer, since the levels differ between cancerous and noncancerous tissue, different cancer types, and different malignancy grades. However, few studies have been conducted on trace element concentrations in brain tumors. Thus, this study aims to review the available literature on trace element changes related to brain tumors, and to identify gaps in the literature. A literature search was done on Google Scholar and PubMed from their start date to January 2018, using terms related to trace element concentration and brain tumors. All brain tumor types were included, and articles could be published in any year. From this search, only 11 articles on this topic could be found. Tumors had significantly higher concentrations of arsenic, thorium, lanthanum, lutetium, cerium, and gadolinium compared to control brain samples. Compared to adjacent tissue, tumor tissue indicated increased magnesium, decreased copper, and contradicting results for zinc. Furthermore, the higher the malignancy grade, the lower the calcium, cadmium, iron, phosphorus and sulfur concentration, and the higher the mercury, manganese, lead, and zinc concentrations. In conclusion, altered trace element levels differ amongst different tumor types, as well as malignancy grades. Consequently, it is impossible to compare data from these studies, and available data are still considerably inconclusive. Ideally, future studies should have a sufficient samples size, compare different tumor types, and compare tumors with adjacent healthy tissue as well as with samples from unaffected matched brains. Anat Rec, 303:1293-1299, 2020. © 2019 American Association for Anatomy.

Distinct Phenotypic Clusters of Glioblastoma Growth and Response Kinetics Predict Survival

PURPOSE

Despite the intra- and intertumoral heterogeneity seen in glioblastoma multiforme (GBM), there is little definitive data on the underlying cause of the differences in patient survivals. Serial imaging assessment of tumor growth allows quantification of tumor growth kinetics (TGK) measured in terms of changes in the velocity of radial expansion seen on imaging. Because a systematic study of this entire TGK phenotype-growth before treatment and during each treatment to recurrence -has never been coordinately studied in GBMs, we sought to identify whether patients cluster into discrete groups on the basis of their TGK.

PATIENTS AND METHODS

From our multi-institutional database, we identified 48 patients who underwent maximally safe resection followed by radiotherapy with imaging follow-up through the time of recurrence. The patients were then clustered into two groups through a k-means algorithm taking as input only the TGK before and during treatment.

RESULTS

There was a significant survival difference between the clusters ( P = .003). Paradoxically, patients among the long-lived cluster had significantly larger tumors at diagnosis ( P = .027) and faster growth before treatment ( P = .003) but demonstrated a better response to adjuvant chemotherapy ( P = .048). A predictive model was built to identify which cluster patients would likely fall into on the basis of information that would be available to clinicians immediately after radiotherapy (accuracy, 90.3%).

CONCLUSION

Dichotomizing the heterogeneity of GBMs into two populations-one faster growing yet more responsive with increased survival and one slower growing yet less responsive with shorter survival-suggests that many patients who receive standard-of-care treatments may get better benefit from select alternative treatments.

Molecular Study of Long-Term Survivors of Glioblastoma by Gene-Targeted Next-Generation Sequencing

Glioblastoma (GBM) is the most common malignant adult primary brain tumor. Despite its high lethality, a small proportion of patients have a relatively long overall survival (OS). Here we report a study of a series of 74 GBM samples from 29 long-term survivors ([LTS] OS ≥36 months) and 45 non-LTS. Using next-generation sequencing, we analyzed genetic alterations in the genes most frequently altered in gliomas. Approximately 20% of LTS had a mutation in the IDH1 or IDH2 (IDH) genes, denoting the relevance of this molecular prognostic factor. A new molecular group of GBMs harbored alterations in ATRX or DAXX genes in the absence of driver IDH or H3F3A mutations. These patients tended to have a slightly better prognosis, to be younger at diagnosis, and to present frontal or temporal tumors, and, morphologically, to present giant tumor cells. A significant fraction of LTS GBM patients had tumors with 1 or more alterations in the relevant GBM signaling pathways (RTK/PI3K, TP53 and RB1). In these patients, the PDGFRA alteration is suggested to be a favorable molecular factor. Our findings here are relevant for developing future targeted therapies and for identifying molecular prognostic factors in GBM patients.

Molecular profile of long-term survivors of glioblastoma: A scoping review of the literature

Molecular aberrations of malignancy are becoming widely recognized as important predictive and prognostic markers for treatment response and survival in oncology and have been linked to the discovery of novel treatment targets. This area of research in glioblastoma continues to evolve. The aim of this scoping review was to document the hallmark molecular characteristics of long-term survivors of glioblastoma. MEDLINE, Scopus and EMBASE were searched with core concepts: (1) glioblastoma, (2) long-term survivor and (3) molecular OR mutation. A thematic analysis was undertaken of the 18 included studies. Four main classes of characteristics were obtained: IDH mutation, MGMT methylation, other known characteristics and novel discoveries. While MGMT methylation or the combination with IDH mutation are suggested to be hallmark characteristics, there remains enough uncertainty to suggest further factors may be involved, such as CD34 expression. Further research is required to accurately describe hallmark molecular characteristics of long-term survivors to assist in defining these patients at diagnosis, preventing treatment complications and discovering novel treatments.

ENvironmental Dynamics Underlying Responsive Extreme Survivors (ENDURES) of Glioblastoma: A Multidisciplinary Team-based, Multifactorial Analytical Approach

Although glioblastoma (GBM) is a fatal primary brain cancer with short median survival of 15 months, a small number of patients survive >5 years after diagnosis; they are known as extreme survivors (ES). Because of their rarity, very little is known about what differentiates these outliers from other patients with GBM. For the purpose of identifying unknown drivers of extreme survivorship in GBM, the ENDURES consortium (ENvironmental Dynamics Underlying Responsive Extreme Survivors of GBM) was developed. This consortium is a multicenter collaborative network of investigators focused on the integration of multiple types of clinical data and the creation of patient-specific models of tumor growth informed by radiographic and histologic parameters. Leveraging our combined resources, the goals of the ENDURES consortium are 2-fold: (1) to build a curated, searchable, multilayered repository housing clinical and outcome data on a large cohort of ES patients with GBM; and (2) to leverage the ENDURES repository for new insights into tumor behavior and novel targets for prolonging survival for all patients with GBM. In this article, the authors review the available literature and discuss what is already known about ES. The authors then describe the creation of their consortium and some preliminary results.

G-quadruplex ligand RHPS4 radiosensitizes glioblastoma xenograft in vivo through a differential targeting of bulky differentiated- and stem-cancer cells

BACKGROUND

Glioblastoma is the most aggressive and most lethal primary brain tumor in the adulthood. Current standard therapies are not curative and novel therapeutic options are urgently required. Present knowledge suggests that the continued glioblastoma growth and recurrence is determined by glioblastoma stem-like cells (GSCs), which display self-renewal, tumorigenic potential, and increased radio- and chemo-resistance. The G-quadruplex ligand RHPS4 displays in vitro radiosensitizing effect in GBM radioresistant cells through the targeting and dysfunctionalization of telomeres but RHPS4 and Ionizing Radiation (IR) combined treatment efficacy in vivo has not been explored so far.

METHODS

RHPS4 and IR combined effects were tested in vivo in a heterotopic mice xenograft model and in vitro in stem-like cells derived from U251MG and from four GBM patients. Cell growth assays, cytogenetic analysis, immunoblotting, gene expression and cytofluorimetric analysis were performed in order to characterize the response of differentiated and stem-like cells to RHPS4 and IR in single and combined treatments.

RESULTS

RHPS4 administration and IR exposure is very effective in blocking tumor growth in vivo up to 65 days. The tumor volume reduction and the long-term tumor control suggested the targeting of the stem cell compartment. Interestingly, RHPS4 treatment was able to strongly reduce cell proliferation in GSCs but, unexpectedly, did not synergize with IR. Lack of radiosensitization was supported by the GSCs telomeric-resistance observed as the total absence of telomere-involving chromosomal aberrations. Remarkably, RHPS4 treatment determined a strong reduction of CHK1 and RAD51 proteins and transcript levels suggesting that the inhibition of GSCs growth is determined by the impairment of the replication stress (RS) response and DNA repair.

CONCLUSIONS

We propose that the potent antiproliferative effect of RHPS4 in GSCs is not determined by telomeric dysfunction but is achieved by the induction of RS and by the concomitant depletion of CHK1 and RAD51, leading to DNA damage and cell death. These data open to novel therapeutic options for the targeting of GSCs, indicating that the combined inhibition of cell-cycle checkpoints and DNA repair proteins provides the most effective means to overcome resistance of GSC to genotoxic insults.

Endoscopic Fluorescence-Guided Resection Increases Radicality in Glioblastoma Surgery

BACKGROUND

Several studies have proven the benefit of a greater extent of resection on progression-free survival and overall survival in glioblastoma (GBM). Possible reasons for incomplete tumor resection might be wrong interpretation of fading fluorescence or overseen fluorescent tumor tissue by a lacking line of sight between tumor tissue and the microscope.

OBJECTIVE

To evaluate if an endoscope being capable of inducing fluorescence might overcome some limitations of microscopic fluorescence-guided (FG) resection.

METHODS

5-Aminolevulinic acid (20 mg/kg) was given 4 h before surgery. Microsurgical resection of all fluorescent tissue was performed. Then, the resection cavity was scanned with the endoscope. Fluorescent tissue, not being visualized by the microscope, was additionally removed and histopathologically examined separately. Neuronavigation was used for defining the sites of additional tumor resection. All patients underwent magnetic resonance imaging within 48 h after surgery.

RESULTS

Twenty patients with GBM were operated using microscopic and endoscopic FG resection. In all patients, additional fluorescent tissue was detected with the endoscope. This tissue was completely resected in 19 patients (95%). Eloquent localization precluded complete resection in the remaining patient. In 19 patients (95%), histopathological examination confirmed tumor in the additionally resected tissue. In 19 patients (95%), complete resection was confirmed. In all patients, endoscopic FG resection reached beyond the borders of contrast-enhancing tumor.

CONCLUSION

Endoscopic FG resection of GBM allows increasing the complete resection rate substantially and therefore is a useful adjunct to microscopic FG resection.

Inhibition of Proliferation by Knockdown of Transmembrane (TMEM) 168 in Glioblastoma Cells via Suppression of Wnt/β-Catenin Pathway

Human glioblastoma multiforme (GBM) accounts for the majority of human brain gliomas. Several TMEM proteins, such as TMEM 45A, TMEM 97, and TMEM 140, are implicated in human brain gliomas. However, the roles of TMEM168 in human GBM remain poorly understood. Herein we found that mRNA levels of TMEM168 were overexpressed in GBM patients (n = 85) when compared with healthy people (n = 10), which was also supported by data from The Cancer Genome Atlas (TCGA). Kaplan–Meier analysis of Gene Expression Omnibus dataset GSE16011 suggested that enhanced TMEM168 expression was associated with shorter survival time. To investigate whether and how TMEM168 functioned in the tumorigenesis of human GBM cells, two human GBM cell lines (U87 and U373) were used for study. Lithium chloride (LiCl), an activator for Wnt/β-catenin pathway, was used for the treatment. Our data suggested that siRNA-TMEM168 (siTMEM168) prevented viability of U87 and U373 cells, induced cell cycle arrest (G₀/G₁ phase) and promoted apoptosis, and the mechanisms involved in blocking Wnt/β-catenin pathway, as evidenced by reducing expression of β-catenin, C-myc, cyclin D1, and survivin. Furthermore, the inhibited effect of siTMEM168 on human GBM cell growth was significantly alleviated with additional LiCl treatment, substantiating the involvement of the Wnt/β-catenin pathway in this process. In summary, our data demonstrated that TMEM168 may represent a therapeutic target for the treatment of human GBM.

A radiomics nomogram based on multiparametric MRI might stratify glioblastoma patients according to survival

OBJECTIVES

To construct a radiomics nomogram for the individualized estimation of the survival stratification in glioblastoma (GBM) patients using the multiregional information extracted from multiparametric MRI, which could facilitate the clinical decision-making for GBM patients.

MATERIALS AND METHODS

A total of 105 eligible GBM patients (57 in the long-term and 48 in the short-term survival groups, separated by an overall survival of 12 months) were selected from the Cancer Genome Atlas. These patients were divided into a training set (n = 70) and a validation set (n = 35). Radiomics features (n = 4000) were extracted from multiple regions of the GBM using multiparametric MRI. Then, a radiomics signature was constructed using least absolute shrinkage and selection operator regression for each patient in the training set. Combined with clinical risk factors, a radiomics nomogram was constructed based on a multivariate logistic regression model. The performance of this radiomics nomogram was assessed by calibration, discrimination, and clinical usefulness.

RESULTS

The radiomics signature consisted of 25 selected features and performed better than clinical risk factors (i.e., age, Karnofsky performance status, and treatment strategy) in survival stratification. When the radiomics signature and clinical risk factors were combined, the radiomics nomogram exhibited promising discrimination in the training (C-index, 0.971) and validation (C-index, 0.974) sets. The favorable calibration and decision curve analysis indicated the clinical usefulness of the radiomics nomogram.

CONCLUSIONS

The presented radiomics nomogram, as a non-invasive prediction tool, could exhibit a favorable predictive accuracy and provide individualized probabilities of survival stratification for GBM patients.

KEY POINTS

• Non-invasive survival stratification of GBM patients can be obtained with a radiomics nomogram. • The proposed nomogram constructed by radiomics signature selected from 4000 radiomics features, combined with independent clinical risk factors such as age, Karnofsky performance status, and treatment strategy. • The proposed radiomics nomogram exhibited good calibration and discrimination for survival stratification of GBM patients in both training (C-index, 0.971) and validation (C-index, 0.974) sets.

ALDH1A3 induces mesenchymal differentiation and serves as a predictor for survival in glioblastoma

As aldehyde dehydrogenase (ALDH) is a novel stem cell marker, increasing studies have confirmed that high ALDH activity promotes tumorigenesis and progression in cancers. Some preliminary studies have found that ALDH1A3 may play an important role in glioma malignant progression, but so far there was no conclusive conclusion. The purpose of our study was to elucidate the mechanisms by which ALDH1A3 regulated in glioma and to provide practical tools for clinical application. Aldefluor, flow cytometry sorting and qRT-PCR were performed to verify the role of ALDH1A3 in ALDH activity maintenance. Transwell, immunofluorescence, glycolytic assays, and orthotopic xenograft models were used to explore ALDH1A3 bio-functions in GBM. LASSO-COX, COX survival analysis and Kaplan–Meier analysis were used to establish the prognostic evaluation system and predict postoperative chemotherapy sensitivity of GBMs. Our integrated study found that (1) ALDH1A3 associates with mesenchymal differentiation of GBM in Eastern and Western world patients. (2) ALDH1A3 plays a critical role in ALDH activity maintenance. (3) ALDH1A3 is an activator of mesenchymal transformation in GBM. (4) ALDH1A3-derived PMT markers’ molecular signature can predict 1-, 2-, and 3-year survival rates of GBMs precisely. In conclusion, ALDH1A3 was a major contributor to ALDH activity and a key driver in triggering mesenchymal transformation in GBM. ALDH1A3-based molecular classification scheme can help to improve guidance for prognosis forecasting and individualized treatment decision making for GBM patients.