A Critical Overview of Targeted Therapies for Glioblastoma

Nanomaterials for Diagnosis and Treatment of Brain Cancer: Recent Updates

Brain tumors, especially glioblastoma, remain the most aggressive form of all the cancers because of inefficient diagnosis and profiling. Nanostructures, such as metallic nanostructures, silica nano-vehicles, quantum dots, lipid nanoparticles (NPs) and polymeric NPs, with high specificity have made it possible to permeate the blood–brain barrier (BBB). NPs possess optical, magnetic and photodynamic properties that can be exploited by surface modification, bio composition, contrast agents’ encapsulation and coating by tumor-derived cells. Hence, nanotechnology has brought on a revolution in the field of diagnosis and imaging of brain tumors and cancers. Recently, nanomaterials with biomimetic functions have been introduced to efficiently cross the BBB to be engulfed by deep skin tumors and cancer malignancies for imaging. The review focuses on nanotechnology-based diagnostic and imaging approaches for exploration in brain tumors and cancers. Moreover, the review also summarizes a few strategies to image glioblastoma and cancers by multimodal functional nanocomposites for more precise and accurate clinical diagnosis. Their unique physicochemical attributes, including nanoscale sizes, larger surface area, explicit structural features and ability to encapsulate diverse molecules on their surface, render nanostructured materials as excellent nano-vehicles to cross the blood–brain barrier and convey drug molecules to their target region. This review sheds light on the current progress of various kinds of nanomaterials, such as liposomes, nano-micelles, dendrimers, carbon nanotubes, carbon dots and NPs (gold, silver and zinc oxide NPs), for efficient drug delivery in the treatment and diagnosis of brain cancer.

Prognostic relevance of temporal muscle thickness as a marker of sarcopenia in patients with glioblastoma at diagnosis

OBJECTIVES

Temporal muscle thickness (TMT) is a surrogate marker of sarcopenia, correlated with survival expectancy in patients suffering from brain metastases and recurrent or treated glioblastoma. We evaluated the prognostic relevance of TMT measured on brain MRIs acquired at diagnosis in patients affected by glioblastoma.

METHODS

We retrospectively enrolled 51 patients in our Institution affected by methylated MGMT promoter, IDH1-2 wild-type glioblastoma, who underwent complete surgical resection and subsequent radiotherapy with concomitant and maintenance temozolomide, from January 1, 2015, to April 30, 2017. The last clinical/radiological follow-up date was set to September 3, 2019. TMT was measured bilaterally on reformatted post-contrast 3D MPRAGE images, acquired on our 3-T scanner no more than 2 days before surgery. The median, 25th, and 75th percentile TMT values were identified and population was subdivided accordingly; afterwards, statistical analyses were performed to verify the association among overall survival (OS) and TMT, sex, age, and ECOG performance status.

RESULTS

In our cohort, the median OS was 20 months (range 3-51). Patients with a TMT ≥ 8.4 mm (median value) did not show a statistically significant increase in OS (Cox regression model: HR 1.34, 95% CI 0.68-2.63, p = 0.403). Similarly, patients with a TMT ≥ 9.85 mm (fourth quartile) did not differ in OS compared to those with TMT ≤ 7 mm (first quartile). The statistical analyses confirmed a significant association among TMT and sex (p = 0.0186), but none for age (p = 0.642) and performance status (p = 0.3982).

CONCLUSIONS

In our homogeneous cohort of patients with glioblastoma at diagnosis, TMT was not associated with prognosis, age, or ECOG performance status.

KEY POINTS

• Temporal muscle thickness (TMT) is a surrogate marker of sarcopenia and has been correlated with survival expectancy in patients suffering from brain metastases and recurrent or treated glioblastoma. • We appraised the correlation among TMT and survival, sex, age at surgery, and performance status, measured on brain MRIs of patients affected by glioblastoma at diagnosis. • TMT did not show any significant correlation with prognosis, age at surgery, or performance status, and its usefulness might be restricted only to patients with brain metastases and recurrent or treated glioblastoma.

Targeted delivery of small noncoding RNA for glioblastoma

Aberrant expression of certain genes and microRNAs (miRNAs) has been shown to drive cancer development and progression, thus the modification of aberrant gene and miRNA expression presents an opportunity for therapeutic targeting. Ectopic modulation of a single dysregulated miRNA has the potential to revert therapeutically unfavorable gene expression in cancer cells by targeting multiple genes simultaneously. Although the use of noncoding RNA-based cancer therapy is a promising approach, the lack of a feasible delivery platform for small noncoding RNAs has hindered the development of this therapeutic modality. Recently, however, there has been an evolution in RNA nanotechnology, in which small noncoding RNA is loaded onto nanoparticles derived from the pRNA-3WJ viral RNA motif of the bacteriophage phi29. Preclinical studies have shown the capacity of this technology to specifically target tumor cells by conjugating these nanoparticles with ligands specific for cancer cells and resulting in the endocytic delivery of siRNA and miRNA inhibitors directly into the cell. Here we provide a systematic review of the various strategies, which have been utilized for miRNA delivery with a specific focus on the preclinical evaluation of promising RNA nanoparticles for glioblastoma (GBM) targeted therapy.

Injectable biomaterials for treatment of glioblastoma

Despite ongoing advancements in the field of medicine, glioblastoma multiforme (GBM) is presently incurable, making this advanced brain tumor the deadliest tumor type in the central nervous system. The primary treatment strategies for GBM (i.e. surgical resection, radiation therapy, chemotherapy, and newly incorporated targeted therapies) fail to overcome the challenging characteristics of highly aggressive GBM tumors and are presently given with the goal of increasing the quality of life for patients. With the aim of creating effective treatment solutions, research has shifted toward utilizing injectable biomaterial adjuncts to minimize invasiveness of treatment, provide spatiotemporal control of therapeutic delivery, and engage with cells through material-cell interfaces. This review aims to summarize the limitations of the current standard of care for GBM, discuss how these limitations can be addressed by local employment of injectable biomaterial systems, and highlight developments in the field of biomaterials for these applications.

Low mitochondrial DNA copy number is associated with poor prognosis and treatment resistance in glioblastoma

INTRODUCTION

Mitochondrial DNA (mtDNA) content in several solid tumors was found to be lower than in their normal counterparts. However, there is paucity of literature on the clinical significance of mtDNA content in glioblastoma and its effect on treatment response. Hence, we studied the prognostic significance of mtDNA content in glioblastoma tumor tissue and the effect of mtDNA depletion in glioblastoma cells on response to treatment.

MATERIALS AND METHODS

130 newly diagnosed glioblastomas, 32 paired newly diagnosed and recurrent glioblastomas and 35 non-neoplastic brain tissues were utilized for the study. mtDNA content in the patient tumor tissue was assessed and compared with known biomarkers and patient survival. mtDNA was chemically depleted in malignant glioma cell lines, U87, LN229. The biology and treatment response of parent and depleted cells were compared.

RESULTS

Lower range of mtDNA copy number in glioblastoma was associated with poor overall survival (p = 0.01), progression free survival (p = 0.04) and also with wild type IDH (p = 0.02). In recurrent glioblastoma, mtDNA copy number was higher than newly diagnosed glioblastoma in the patients who received RT (p = 0.01). mtDNA depleted U87 and LN229 cells showed higher survival fraction post radiation exposure when compared to parent lines. The IC50 of TMZ was also higher for mtDNA depleted U87 and LN229 cells. The depleted cells formed more neurospheres than their parent counterparts, thus showing increased stemness of mtDNA depleted cells.

CONCLUSION

Low mtDNA copy number in glioblastoma is associated with poor patient survival and treatment resistance in cell lines possibly by impacting stemness of the glioblastoma cells.

Pharmacological Modulation of Blood-Brain Barrier Permeability by Kinin Analogs in Normal and Pathologic Conditions

The blood–brain barrier (BBB) is a major obstacle to the development of effective diagnostics and therapeutics for brain cancers and other central nervous system diseases. Peptide agonist analogs of kinin B1 and B2 receptors, acting as BBB permeabilizers, have been utilized to overcome this barrier. The purpose of the study was to provide new insights for the potential utility of kinin analogs as brain drug delivery adjuvants. In vivo imaging studies were conducted in various animal models (primary/secondary brain cancers, late radiation-induced brain injury) to quantify BBB permeability in response to kinin agonist administrations. Results showed that kinin B1 (B1R) and B2 receptors (B2R) agonists increase the BBB penetration of chemotherapeutic doxorubicin to glioma sites, with additive effects when applied in combination. B2R agonist also enabled extravasation of high-molecular-weight fluorescent dextrans (155 kDa and 2 MDa) in brains of normal mice. Moreover, a systemic single dose of B2R agonist did not increase the incidence of metastatic brain tumors originating from circulating breast cancer cells. Lastly, B2R agonist promoted the selective delivery of co-injected diagnostic MRI agent Magnevist in irradiated brain areas, depicting increased vascular B2R expression. Altogether, our findings suggest additional evidence for using kinin analogs to facilitate specific access of drugs to the brain.

A facile and scalable in production non-viral gene engineered mesenchymal stem cells for effective suppression of temozolomide-resistant (TMZR) glioblastoma growth

BACKGROUND

Mesenchymal stem cells (MSCs) serve as an attractive vehicle for cell-directed enzyme prodrug therapy (CDEPT) due to their unique tumour-nesting ability. Such approach holds high therapeutic potential for treating solid tumours including glioblastoma multiforme (GBM), a devastating disease with limited effective treatment options. Currently, it is a common practice in research and clinical manufacturing to use viruses to deliver therapeutic genes into MSCs. However, this is limited by the inherent issues of safety, high cost and demanding manufacturing processes. The aim of this study is to identify a facile, scalable in production and highly efficient non-viral method to transiently engineer MSCs for prolonged and exceptionally high expression of a fused transgene: yeast cytosine deaminase::uracil phosphoribosyl-transferase::green fluorescent protein (CD::UPRT::GFP).

METHODS

MSCs were transfected with linear polyethylenimine using a cpg-free plasmid encoding the transgene in the presence of a combination of fusogenic lipids and β tubulin deacetylase inhibitor (Enhancer). Process scalability was evaluated in various planar vessels and microcarrier-based bioreactor. The transfection efficiency was determined with flow cytometry, and the therapeutic efficacy of CD::UPRT::GFP expressing MSCs was evaluated in cocultures with temozolomide (TMZ)-sensitive or TMZ-resistant human glioblastoma cell lines. In the presence of 5-fluorocytosine (5FC), the 5-fluorouracil-mediated cytotoxicity was determined by performing colometric MTS assay. In vivo antitumor effects were examined by local injection into subcutaneous TMZ-resistant tumors implanted in the athymic nude mice.

RESULTS

At > 90% transfection efficiency, the phenotype, differentiation potential and tumour tropism of MSCs were unaltered. High reproducibility was observed in all scales of transfection. The therapeutically modified MSCs displayed strong cytotoxicity towards both TMZ-sensitive and TMZ-resistant U251-MG and U87-MG cell lines only in the presence of 5FC. The effectiveness of this approach was further validated with other well-characterized and clinically annotated patient-derived GBM cells. Additionally, a long-term suppression (> 30 days) of the growth of a subcutaneous TMZ-resistant U-251MG tumour was demonstrated.

CONCLUSIONS

Collectively, this highly efficient non-viral workflow could potentially enable the scalable translation of therapeutically engineered MSC for the treatment of TMZ-resistant GBM and other applications beyond the scope of this study.

Advances in drug delivery technology for the treatment of glioblastoma multiforme

Glioblastoma multiforme (GBM) is a particularly aggressive and malignant type of brain tumor, notorious for its high recurrence rate and low survival rate. The treatment of GBM is challenging mainly because several issues associated with the GBM microenvironment have not yet been resolved. These obstacles originate from a variety of factors such as genetics, anatomy, and cytology, all of which collectively hinder the treatment of GBM. Recent advances in materials and device engineering have presented new perspectives with regard to unconventional drug administration methods for GBM treatment. Such novel drug delivery approaches, based on the clear understanding of the intrinsic properties of GBM, have shown promise in overcoming some of the obstacles. In this review, we first recapitulate the first-line therapy and clinical challenges in the current treatment of GBM. Afterwards, we introduce the latest technological advances in drug delivery strategies to improve the efficiency for GBM treatment, mainly focusing on materials and devices. We describe such efforts by classifying them into two categories, systemic and local drug delivery. Finally, we discuss unmet challenges and prospects for the clinical translation of these drug delivery technologies.

Vesiclemia: counting on extracellular vesicles for glioblastoma patients

Although rare, glioblastoma is a devastating tumor of the central nervous system characterized by a poor survival and an extremely dark prognosis, making its diagnosis, treatment, and monitoring highly challenging. Numerous studies have highlighted extracellular vesicles (EVs) as key players of tumor growth, invasiveness, and resistance, as they carry oncogenic material. Moreover, EVs have been shown to communicate locally in a paracrine way but also at remote throughout the organism. Indeed, recent reports demonstrated the presence of brain tumor-derived EVs into body fluids such as plasma and cerebrospinal fluid. Fluid-associated EVs have indeed been suspected to reflect quantitative and qualitative information about the status and fate of the tumor and can potentially act as a resource for noninvasive biomarkers that might assist in diagnosis, treatment, and follow-up of glioblastoma patients. Here, we coined the name vesiclemia to define the concentration of plasmatic EVs, an intuitive term to be directly transposed in the clinical jargon.

Modulating microenvironments for treating glioblastoma

Purpose of review

This review focuses on the development and progression of glioblastoma through the brain and glioma microenvironment. Specifically we highlight how the tumor microenvironment contributes to the hallmarks of cancer in hopes of offering novel therapeutic options and tools to target this microenvironment.

Recent findings

The hallmarks of cancer, which represent elements of cancers that contribute to the disease's malignancy, yet elements within the brain tumor microenvironment, such as other cellular types as well as biochemical and biophysical cues that can each uniquely affect tumor cells, have not been well-described in this context and serve as potential targets for modulation.

Summary

Here, we highlight how the brain tumor microenvironment contributes to the progression and therapeutic response of tumor cells. Specifically, we examine these contributions through the lens of Hanahan & Weinberg's Hallmarks of Cancer in order to identify potential novel targets within the brain that may offer a means to treat brain cancers, including the deadliest brain cancer, glioblastoma.

Personalized and translational approach for malignant brain tumors in the era of precision medicine: the strategic contribution of an experienced neurosurgery laboratory in a modern neurosurgery and neuro-oncology department

Personalized medicine (PM) aims to optimize patient management, taking into account the individual traits of each patient. The main purpose of PM is to obtain the best response, improving health care and lowering costs. Extending traditional approaches, PM introduces novel patient-specific paradigms from diagnosis to treatment, with greater precision. In neuro-oncology, the concept of PM is well established. Indeed, every neurosurgical intervention for brain tumors has always been highly personalized. In recent years, PM has been introduced in neuro-oncology also to design and prescribe specific therapies for the patient and the patient's tumor. The huge advances in basic and translational research in the fields of genetics, molecular and cellular biology, transcriptomics, proteomics, and metabolomics have led to the introduction of PM into clinical practice. The identification of a patient's individual variation map may allow to design selected therapeutic protocols that ensure successful outcomes and minimize harmful side effects. Thus, clinicians can switch from the "one-size-fits-all" approach to PM, ensuring better patient care and high safety margin. Here, we review emerging trends and the current literature about the development of PM in neuro-oncology, considering the positive impact of innovative advanced researches conducted by a neurosurgical laboratory.

The Role of RNA and DNA Aptamers in Glioblastoma Diagnosis and Therapy: A Systematic Review of the Literature

Glioblastoma (GBM) is the most lethal primary brain tumor of the central nervous system in adults. Despite advances in surgical and medical neuro-oncology, the median survival is about 15 months. For this reason, initial diagnosis, prognosis, and targeted therapy of GBM represent very attractive areas of study. Aptamers are short three-dimensional structures of single-stranded nucleic acids (RNA or DNA), identified by an in vitro process, named systematic evolution of ligands by exponential enrichment (SELEX), starting from a partially random oligonucleotide library. They bind to a molecular target with high affinity and specificity and can be easily modified to optimize binding affinity and selectivity. Thanks to their properties (low immunogenicity and toxicity, long stability, and low production variability), a large number of aptamers have been selected against GBM biomarkers and provide specific imaging agents and therapeutics to improve the diagnosis and treatment of GBM. However, the use of aptamers in GBM diagnosis and treatment still represents an underdeveloped topic, mainly due to limited literature in the research world. On these bases, we performed a systematic review aimed at summarizing current knowledge on the new promising DNA and RNA aptamer-based molecules for GBM diagnosis and treatment. Thirty-eight studies from 2000 were included and investigated. Seventeen involved the use of aptamers for GBM diagnosis and 21 for GBM therapy. Our findings showed that a number of DNA and RNA aptamers are promising diagnostic and therapeutic tools for GBM management.

Low Fraction Size Re-irradiation for Large Volume Recurrence of Glial Tumours

The aim of the present study was to evaluate the efficacy of re-irradiation (re-RT) in patients with advanced local relapses of glial tumours and to define the factors influencing the result of the hyper-fractionated external beam therapy on progression after primary management. We have analysed the data of 55 patients with brain tumours (GBM: 28) on progression, who were re-irradiated between January 2007 and December 2018. The mean volume of the recurrent tumour was 118 cm³, and the mean planning target volume (PTV) was 316 cm³, to which 32 Gy was delivered in 20 fractions at least 7.7 months after the first radiotherapy, using 3D conformal radiotherapy (CRT) or intensity modulated radiotherapy (IMRT). The median overall survival (mOS) from the re-RT was 8.4 months, and the 6-month and the 12-month OS rate was 64% and 31%, respectively. The most important factors by univariate analysis, which significantly improved the outcome of re-RT were the longer time interval between the diagnosis and second radiotherapy (p = 0.029), the lower histology grade (p = 0.034), volume of the recurrent tumour (p = 0.006) and Karnofsky performance status (KPS) (p = 0.009) at the re-irradiation. Our low fraction size re-irradiation ≥ 8 months after the first radiotherapy proved to be safe and beneficial for patients with large volume recurrent glial tumours.

Identification of Glioma Cancer Stem Cell Characteristics Based on Weighted Gene Prognosis Module Co-Expression Network Analysis of Transcriptome Data Stemness Indices

Glioma is the most common primary brain tumor in humans and the most deadly. Stem cells, which are characterized by therapeutic resistance and self-renewal, play a critical role in glioma, and therefore the identification of stem cell-related genes in glioma is important. In this study, we collected and evaluated the epigenetically regulated-mRNA expression-based stemness index (EREG-mRNAsi) of The Cancer Genome Atlas (TCGA, http://www.ncbi.nlm.nih.gov/ ) for glioma patient samples, corrected through tumor purity. After EREG-mRNAsi correction, glioma pathological grade and survival were analyzed. The differentially expressed gene (DEG) co-expression network was constructed by weighted gene co-expression network analysis (WGCNA) in TCGA glioma samples to find modules of interest and key genes. Gene ontology (GO) and pathway-enrichment analysis were performed to identify the function of significant genetic modules. Protein-protein interaction (PPI) and co-expression network analysis of key genes was performed for further analysis. In this experiment, we found that corrected EREG-mRNAsi was significantly up-regulated in glioma samples and increased with glioma grade, with G4 having the highest stemness index. Patients with higher corrected EREG-mRNAsi scores had worse overall survival. Fifty-one DEGs in the brown gene module were found to be positively related to EREG-mRNAsi via WGCNA. GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that chromosome segregation and cell cycle molecular function were the major functions in key DEGs. Among these key DEGs, BUB1 showed high connectivity and co-expression, and also high connectivity in PPI. Fifty-one key genes were verified to play a critical role in glioma stem cells. These genes may serve as primary therapeutic targets to inhibit the activity of glioma stem cells.

Protein Palmitoylation Regulates Cell Survival by Modulating XBP1 Activity in Glioblastoma Multiforme

Glioblastoma multiforme (GBM) almost invariably acquires an invasive phenotype, resulting in limited therapeutic options. Protein palmitoylation markedly affects tumorigenesis and malignant progression in GBM. The role of protein palmitoylation in GBM, however, has not been systematically reported. This study aimed to investigate the effect of protein palmitoylation on GBM cell survival and the cell cycle. In this study, most palmitoyltransferases were upregulated in GBM and its cell lines, and protein palmitoylation participated in signaling pathways controlling cell survival and the GBM cell cycle. Inhibition of protein palmitoylation with substrate-analog inhibitors, that is, 2-bromopalmitate, cerulenin, and tunicamycin, induced G₂ cell cycle arrest and cell death in GBM cells through enhanced endoplasmic reticulum (ER) stress. These effects are primarily attributed to the palmitoylation inhibitors activating pro-apoptotic pathways and ER stress signals. Further analysis revealed was the accumulation of SUMOylated XBP1 (X-box binding protein 1) and its transcriptional repression, along with a reduction in XBP1 palmitoylation. Taken together, the present results indicate that protein palmitoylation plays an important role in the survival of GBM cells, further providing a potential therapeutic strategy for GBM.

Comparative study of preclinical mouse models of high-grade glioma for nanomedicine research: the importance of reproducing blood-brain barrier heterogeneity

The clinical translation of new nanoparticle-based therapies for high-grade glioma (HGG) remains extremely poor. This has partly been due to the lack of suitable preclinical mouse models capable of replicating the complex characteristics of recurrent HGG (rHGG), namely the heterogeneous structural and functional characteristics of the blood-brain barrier (BBB). The goal of this study is to compare the characteristics of the tumor BBB of rHGG with two different mouse models of HGG, the ubiquitously used U87 cell line xenograft model and a patient-derived cell line WK1 xenograft model, in order to assess their suitability for nanomedicine research.

Method: Structural MRI was used to assess the extent of BBB opening in mouse models with a fully developed tumor, and dynamic contrast enhanced MRI was used to obtain values of BBB permeability in contrast enhancing tumor. H&E and immunofluorescence staining were used to validate results obtained from the in vivo imaging studies.

Results: The extent of BBB disruption and permeability in the contrast enhancing tumor was significantly higher in the U87 model than in rHGG. These values in the WK1 model are similar to those of rHGG. The U87 model is not infiltrative, has an entirely abnormal and leaky vasculature and it is not of glial origin. The WK1 model infiltrates into the non-neoplastic brain parenchyma, it has both regions with intact BBB and regions with leaky BBB and remains of glial origin.

Conclusion: The WK1 mouse model more accurately reproduces the extent of BBB disruption, the level of BBB permeability and the histopathological characteristics found in rHGG patients than the U87 mouse model, and is therefore a more clinically relevant model for preclinical evaluations of emerging nanoparticle-based therapies for HGG.

Enhanced Anti-Glioma Efficacy by Borneol Combined With CGKRK-Modified Paclitaxel Self-Assembled Redox-Sensitive Nanoparticles

The serious therapeutic obstacles to glioma treatment include poor penetration across the blood-brain barrier (BBB) and low accumulation of therapeutic drugs at tumor sites. In this study, borneol combined with CGKRK peptide (a ligand of the heparan sulfate which overexpress on the glioma cells) modified paclitaxel prodrug self-assembled redox-responsive nanoparticles (CGKRK-PSNPs) were hypothesized to enhance the BBB penetration ability and active tumor targeting efficiency, respectively. The resulting CGKRK-PSNPs possessed a spherical shape with a small particle size (105.61 ± 1.53 nm) and high drug loading for PTX (54.18 ± 1.13%). The drug release behavior proved that CGKRK-PSNPs were highly sensitive to glutathione (GSH) redox environment. The in vitro cell experiments suggested that CGKRK-PSNPs significantly increased the cellular uptake and cytotoxicity of U87MG cells, meanwhile CGKRK-PSNPs showed the low cytotoxicity against BCEC cells. Combined with borneol, CGKRK-PSNPs exhibited enhanced transportation across in vitro BBB model. In intracranial U87MG glioma-bearing nude mice, the higher accumulation of CGKRK-PSNPs combined with borneol was observed through real-time fluorescence image. Moreover, the in vivo anti-glioma results confirmed that CGKRK-PSNPs combined with borneol could improve the anti-glioma efficacy with the prolonged medium survival time (39 days). In conclusion, the collaborative strategy of CGKRK-PSNPs combined with borneol provided a promising drug delivery routine for glioblastoma therapy.

Nucleobindin-2 Promotes the Growth and Invasion of Glioblastoma

Background: Glioblastoma is one of the most malignant tumors in the brain with high mortality. In recent years, immunotherapy and targeted therapy show great prospects in the treatments for glioblastoma, whereas more effective therapeutic targets are still urgently needed to be developed. Nucleobindin-2 (NUCB2) is the precursor protein of nesfatin-1, which have a variety of metabolic functions, such as food intake and temperature regulation. In recent years, the potential link between NUCB2 and the development of multiple cancer was gradually revealed; however, the effects of NUCB2 on the progression of glioblastoma are still unclear. Methods: Immunohistochemical assays were performed to explore the NUCB2 expression levels in 94 samples of glioblastoma and corresponding nontumor tissues; patients were divided into NUCB2 high expression group and low expression group. Clinical analysis related to the clinical features, the potential link between NUCB2 expression levels, and clinical features were analyzed; the effects of NUCB2 on cell proliferation and invasion of glioblastoma were detected through colony formation and MTT assay, and transwell assay respectively. The possible effects of NUCB2 on tumor growth and metastasis were measured in mice. Results: In this study, we demonstrated that NUCB2 over-expression was correlated with the high degree of recurrence of patients with glioblastoma. Further, we also revealed that NUCB2 promoted cell proliferation and invasion of glioblastoma in vitro and promoted the growth and metastasis of glioblastoma in mice. Conclusion: This study provided evidence that NUCB2 might be a novel therapeutic target of glioblastoma.

Trends in glioblastoma: outcomes over time and type of intervention: a systematic evidence based analysis

INTRODUCTION

Despite aggressive treatment with chemoradiotherapy and maximum surgical resection, survival in patients with glioblastoma (GBM) remains poor. Ongoing efforts are aiming to prolong the lifespan of these patients; however, disparities exist in reported survival values with lack of clear evidence that objectively examines GBM survival trends. We aim to describe the current status and advances in the survival of patients with GBM, by analyzing median overall survival through time and between treatment modalities.

METHODS

A systematic review was conducted according to PRISMA guidelines to identify articles of newly diagnosed glioblastoma from 1978 to 2018. Full-text glioblastoma papers with human subjects, ≥ 18 years old, and n ≥ 25, were included for evaluation.

RESULTS

The central tendency of median overall survival (MOS) was 13.5 months (2.3-29.6) and cumulative 5-year survival was 5.8% (0.01%-29.1%), with a significant difference in survival between studies that predate versus postdate the implementation of temozolomide and radiation, [12.5 (2.3-28) vs 15.6 (3.8-29.6) months, P < 0.001]. In clinical trials, bevacizumab [18.2 (10.6-23.0) months], tumor treating fields (TTF) [20.7 (20.5-20.9) months], and vaccines [19.2 (15.3-26.0) months] reported the highest central measure of median survival.

CONCLUSION

Coadministration with radiotherapy and temozolomide provided a statistically significant increase in survival for patients suffering from glioblastoma. However, the natural history for GBM remains poor. Therapies including TTF pooled values of MOS and provide means of prolonging the survival of GBM patients.

Development of an Immune Infiltration-Related Prognostic Scoring System Based on the Genomic Landscape Analysis of Glioblastoma Multiforme

Introduction: Glioblastoma multiforme (GBM) is the most common deadly brain malignancy and lacks effective therapies. Immunotherapy acts as a promising novel strategy, but not for all GBM patients. Therefore, classifying these patients into different prognostic groups is urgent for better personalized management.

Materials and Methods: The Cell type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm was used to estimate the fraction of 22 types of immune-infiltrating cells, and least absolute shrinkage and selection operator (LASSO) Cox regression analysis was performed to construct an immune infiltration-related prognostic scoring system (IIRPSS). Additionally, a quantitative predicting survival nomogram was also established based on the immune risk score (IRS) derived from the IIRPSS. Moreover, we also preliminarily explored the differences in the immune microenvironment between different prognostic groups.

Results: There was a total of 310 appropriate GBM samples (239 from TCGA and 71 from CGGA) included in further analyses after CIBERSORT filtering and data processing. The IIRPSS consisting of 17 types of immune cell fractions was constructed in TCGA cohort, the patients were successfully classified into different prognostic groups based on their immune risk score (p = 1e-10). What's more, the prognostic performance of the IIRPSS was validated in CGGA cohort (p = 0.005). The nomogram also showed a superior predicting value. (The predicting AUC for 1-, 2-, and 3-year were 0.754, 0.813, and 0.871, respectively). The immune microenvironment analyses reflected a significant immune response and a higher immune checkpoint expression in high-risk immune group.

Conclusion: Our study constructed an IIRPSS, which maybe valuable to help clinicians select candidates most likely to benefit from immunological checkpoint inhibitors (ICIs) and laid the foundation for further improving personalized immunotherapy in patients with GBM.

Downregulation of SNRPG induces cell cycle arrest and sensitizes human glioblastoma cells to temozolomide by targeting Myc through a p53-dependent signaling pathway

Objective: Temozolomide (TMZ) is commonly used for glioblastoma multiforme (GBM) chemotherapy. However, drug resistance limits its therapeutic effect in GBM treatment. RNA-binding proteins (RBPs) have vital roles in posttranscriptional events. While disturbance of RBP-RNA network activity is potentially associated with cancer development, the precise mechanisms are not fully known. The SNRPG gene, encoding small nuclear ribonucleoprotein polypeptide G, was recently found to be related to cancer incidence, but its exact function has yet to be elucidated. Methods:SNRPG knockdown was achieved via short hairpin RNAs. Gene expression profiling and Western blot analyses were used to identify potential glioma cell growth signaling pathways affected by SNRPG. Xenograft tumors were examined to determine the carcinogenic effects of SNRPG on glioma tissues. Results: The SNRPG-mediated inhibitory effect on glioma cells might be due to the targeted prevention of Myc and p53. In addition, the effects of SNRPG loss on p53 levels and cell cycle progression were found to be Myc-dependent. Furthermore, SNRPG was increased in TMZ-resistant GBM cells, and downregulation of SNRPG potentially sensitized resistant cells to TMZ, suggesting that SNRPG deficiency decreases the chemoresistance of GBM cells to TMZ via the p53 signaling pathway. Our data confirmed that SNRPG suppression sensitizes GBM cells to TMZ by targeting Myc via the p53 signaling cascade. Conclusions: These results indicated that SNRPG is a probable molecular target of GBM and suggested that suppressing SNRPG in resistant GBM cells might be a substantially beneficial method for overcoming essential drug resistance.

Potential implications of hydrogen peroxide in the pathogenesis and therapeutic strategies of gliomas

Glioma is the most common type of primary brain tumor, and it has a high mortality rate. Currently, there are only a few therapeutic approaches for gliomas, and their effects are unsatisfactory. Therefore, uncovering the pathogenesis and exploring more therapeutic strategies for the treatment of gliomas are urgently needed to overcome the ongoing challenges. Cellular redox imbalance has been shown to be associated with the initiation and progression of gliomas. Among reactive oxygen species (ROS), hydrogen peroxide (H₂O₂) is considered the most suitable for redox signaling and is a potential candidate as a key molecule that determines the fate of cancer cells. In this review, we discuss the potential cellular and molecular roles of H₂O₂ in gliomagenesis and explore the potential implications of H₂O₂ in radiotherapy and chemotherapy and in the ongoing challenges of current glioma treatment. Moreover, we evaluate H₂O₂ as a potential redox sensor and potential driver molecule of nanocatalytic therapeutic strategies for glioma treatment.

Inhibition of Metabolic Shift can Decrease Therapy Resistance in Human High-Grade Glioma Cells

The high-grade brain malignancy, glioblastoma multiforme (GBM), is one of the most aggressive tumours in central nervous system. The developing resistance against recent therapies and the recurrence rate of GBMs are extremely high. In spite several new ongoing trials, GBM therapies could not significantly increase the survival rate of the patients as significantly. The presence of inter- and intra-tumoral heterogeneity of GBMs arise the problem to find both the pre-existing potential resistant clones and the cellular processes which promote the adaptation mechanisms such as multidrug resistance, stem cell-ness or metabolic alterations, etc. In our work, the in situ metabolic heterogeneity of high-grade human glioblastoma cases were analysed by immunohistochemistry using tissue-microarray. The potential importance of the detected metabolic heterogeneity was tested in three glioma cell lines (grade III-IV) using protein expression analyses (Western blot and WES Simple) and therapeutic drug (temozolomide), metabolic inhibitor treatments (including glutaminase inhibitor) to compare the effects of rapamycin (RAPA) and glutaminase inhibitor combinations in vitro (Alamar Blue and SRB tests). The importance of individual differences and metabolic alterations were observed in mono-therapeutic failures, especially the enhanced Rictor expressions after different mono-treatments in correlation to lower sensitivity (temozolomide, doxycycline, etomoxir, BPTES). RAPA combinations with other metabolic inhibitors were the best strategies except for RAPA+glutaminase inhibitor. These observations underline the importance of multi-targeting metabolic pathways. Finally, our data suggest that the detected metabolic heterogeneity (the high mTORC2 complex activity, enhanced expression of Rictor, p-Akt, p-S6, CPT1A, and LDHA enzymes in glioma cases) and the microenvironmental or treatment induced metabolic shift can be potential targets in combination therapy. Therefore, it should be considered to map tissue heterogeneity and alterations with several cellular metabolism markers in biopsy materials after applying recently available or new treatments.

Recurrent or Refractory High-Grade Gliomas Treated by Convection-Enhanced Delivery of a TGFβ2-Targeting RNA Therapeutic: A Post-Hoc Analysis with Long-Term Follow-Up

Background. OT101 is a first-in-class RNA therapeutic designed to abrogate the immunosuppressive actions of transforming growth factor beta 2 (TGFβ2). Here, we report our post-hoc analysis of the single-agent activity of OT101 in adult patients with recurrent and/or refractory (R/R) high-grade gliomas. Methods. In a Phase 2 clinical trial (ClinicalTrials.gov, NCT00431561), OT101 was administered to 89 R/R high-grade glioma (HGG) (anaplastic astrocytoma/AA: 27; glioblastoma multiforme/GBM: 62) patients with an intratumoral catheter using a convection enhanced delivery (CED) system. Seventy-seven patients (efficacy population; GBM: 51; AA: 26) received at least the intended minimum number of four OT101 treatment cycles. Response determinations were based on central review of magnetic resonance imaging (MRI) scans according to the McDonald criteria. Standard statistical methods were applied for the analysis of data. Findings. Nineteen patients had a complete response (CR) or partial response (PR) following a slow but robust size reduction of their target lesions (median time for 90% reduction of the baseline tumor volume = 11.7 months, range: 4.9-57.7 months). The mean log reduction of the tumor volume was 2.2 ± 0.4 (median = 1.4: range: 0.4-4.5) logs. In addition, seven patients had a stable disease (SD) lasting ≥6 months. For the combined group of 26 AA/GBM patients with favorable responses, the median progression-free survival (PFS) of 1109 days and overall survival (OS) of 1280 days were significantly better than the median PFS (p < 0.00001) and OS (p < 0.00001) of the non-responders among the 89 patients or the 77-patient efficacy population. Conclusion. Intratumorally administered OT101 exhibits clinically meaningful single-agent activity and induces durable CR/PR/SD in R/R HGG patients.

Enhancing Radiotherapeutic Effect With Nanoparticle-Mediated Radiosensitizer Delivery Guided By Focused Gamma Rays In Lewis Lung Carcinoma-Bearing Mouse Brain Tumor Models

Background

Targeting radiosensitizer-incorporated nanoparticles to a tumor could allow for less normal tissue toxicity with more efficient drug release, thus improving the efficacy and safety of radiation treatment. The aim of this study was to improve tumor-specific delivery and bioavailability of a nanoparticle-mediated radiosensitizer in mouse brain tumor models.

Methods

A pH-sensitive nanoparticle, chitoPEGAcHIS, was conjugated to recombinant peptide HVGGSSV that could bind to tax-interaction protein 1 (TIP-1) as a radiation-inducible receptor. Then the c-Jun N-terminal kinase (JNK) inhibitor, SP600125 was incorporated into this copolymer to fabricate a HVGGSSV-chitoPEGAcHIS-SP600125 (HVSP-NP) nanoradiosensitizer. In vitro and in vivo radiation treatment were performed using a Gamma Knife unit. The tumor targetability of HVSP-NP was estimated by optical bioluminescence. Synergistic therapeutic effects of radiation treatment and HVSP-NP were investigated in Lewis lung carcinoma (LLC) cell-bearing mouse brain tumor models.

Results

The SP600125 JNK inhibitor effectively reduced DNA damage repair to irradiated LLC cells. A pH sensitivity assay indicated that HVSP-NP swelled at acidic pH and increased in diameter, and its release rate gradually increased. Optical bioluminescence assay showed that radiation induced TIP-1 expression in mouse brain tumor and that the nanoradiosensitizer selectively targeted irradiated tumors. Radiation treatment with HVSP-NP induced greater apoptosis and significantly inhibited tumor growth compared to radiation alone.

Conclusion

As a novel nanoradiosensitizer, HVSP-NP was found to be able to selectively target irradiated tumors and significantly increase tumor growth delay in LLC-bearing mouse brain tumor models. This research shows that delivering a pH-sensitive nanoradiosensitizer to a brain tumor in which TIP-1 is induced by radiation can result in improved radiosensitizer-release in an acidic microenvironment of tumor tissue and in created synergistic effects in radiation treatment.

Contrast-to-Dose Relationship of Gadopiclenol, an MRI Macrocyclic Gadolinium-based Contrast Agent, Compared with Gadoterate, Gadobenate, and Gadobutrol in a Rat Brain Tumor Model

Background Detection of cerebral lesions at MRI may benefit from a chemically stable and more sensitively detected gadolinium-based contrast agent (GBCA). Gadopiclenol, a macrocyclic GBCA with at least twofold higher relaxivity, is currently undergoing clinical trials in humans. Purpose To determine the relationship between MRI contrast enhancement and the injected dose of gadopiclenol in a glioma rat model compared with those of conventional GBCA at label dose. Materials and Methods Between April and July 2012, 32 rats implanted with C6 glioma received two intravenous injections at a 24-hour interval. The injections were randomly selected among five doses of gadopiclenol (0.025, 0.05, 0.075, 0.1, and 0.2 mmol/kg) and three reference GBCAs (gadoterate meglumine, gadobutrol, and gadobenate dimeglumine) at 0.1 mmol/kg. MRI tumor enhancement was assessed on T1-weighted images before and up to 30 minutes after injection. Two blinded radiologists visually and qualitatively scored contrast enhancement, border delineation, and visualization of tumor morphology. Quantitatively, variations in contrast-to-noise ratio (ΔCNR) between tumor and contralateral parenchyma were calculated at each time point and were compared for each treatment at 5 minutes by using a mixed model after normality test. Results A total of 24 rats underwent the complete protocol (n = 5-7 per group). A linear dose-dependent ΔCNR relationship was observed between 0.025 and 0.1 mmol/kg for gadopiclenol (R ² = 0.99). No difference in ΔCNR was observed between the three reference GBCAs (P ≥ .55). Gadopiclenol resulted in twofold higher ΔCNR at 0.1 mmol/kg (P < .001 vs gadobutrol and gadoterate, P = .002 vs gadobenate) and similar ΔCNR at 0.05 mmol/kg (P = .56, P > .99, and P = .44 compared with gadobutrol, gadobenate, and gadoterate, respectively). For both readers, 0.05 mmol/kg of gadopiclenol improved contrast enhancement, border delineation, and visualization of tumor morphology (scores > 3 compared with scores between 2 and 3 for the marketed GBCA). Conclusion Gadopiclenol at 0.05 mmol/kg yielded comparable change in contrast-to-noise ratio and morphologic characterization of brain tumors compared with gadobenate, gadoterate, or gadobutrol at 0.1 mmol/kg. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Tweedle in this issue.

Circular RNA USP1 regulates the permeability of blood-tumour barrier via miR-194-5p/FLI1 axis

Recent studies indicate circular RNAs are related to dysregulation of vascular endothelial cell function, yet the underlying mechanisms have remained elusive. Here, we characterized the functional role of circular RNA USP1 (circ‐USP1) in the regulation of the blood‐tumour barrier (BTB) permeability and the potential mechanisms. In the current study, the circ‐USP1 expressing level was up‐regulated in glioma cerebral microvascular endothelial cells (GECs) of the BTB model in vitro. Knockdown of circ‐USP1 disrupted the barrier integrity, increased its permeability as well as reduced tight junction‐related protein claudin‐5, occludin and ZO‐1 expressions in GECs. Bioinformatic prediction and luciferase assay indicated that circ‐USP1 bound to miR‐194‐5p and suppressed its activity. MiR‐194‐5p contributed to circ‐USP1 knockdown‐induced increase of BTB permeability via targeting and down‐regulating transcription factor FLI1. Furthermore, FLI1 regulated the expressions of claudin‐5, occludin and ZO‐1 in GECs through binding to their promoter regions. Single or combined treatment of circ‐USP1 and miR‐194‐5p effectively promoted anti‐tumour drug doxorubicin across BTB to induce apoptosis of glioma cells. Overall, this present study identified the crucial regulation of circ‐USP1 on BTB permeability via miR‐194‐5p/FLI1 axis‐mediated regulation of tight junction proteins, which might facilitate the development of therapeutics against human gliomas.

Evaluation of the Betulinic Acid-Cisplatin conjugate APC and its precursor DE9B for the treatment of human malignant glioma

Despite the existence of multimodal therapy concepts, glioblastoma remains a tumor type with one of the worst prognoses. In particular, the poor prognosis is due to the lack of therapeutic efficacy of chemical agents and irradiation in hypoxic tumor areas. New therapeutic strategies could improve the treatment of glioblastoma. In this study, we investigated the therapeutic efficacy of a conjugate of cisplatin (DDP), a widely used chemotherapeutic agent, and betulinic acid (BA), a natural product from plane tree bark, in glioblastoma cells under different oxygen conditions. We investigated the effects of the BA-DDP conjugate κN',N''-{3-acetyloxy-BA-28-[2-(2-aminoethyl)aminoethyl]amide} dichlorido platinum(II) (APC) and its precursor 3-acetyloxy-BA-28-[2-(2-aminoethyl)aminoethyl]amide (DE9B) on cytotoxicity, cell growth, apoptosis, migration and radiosensitivity compared to BA or DDP alone under different oxygen conditions. Based on the EC₅₀ values, the precursor DE9B exhibited the strongest cytotoxic effects of the analyzed chemotherapeutic agents. The BA-DDP conjugate APC achieved a moderate cytotoxic effect in glioma cells. Both of the newly developed agents induced cell growth delay, apoptosis and inhibition of migration. Furthermore, additive effects could be achieved in combination with irradiation. In contrast to those of BA and DDP, the cell biological effects of APC and DE9B were not influenced by the oxygen concentration. In this study, the linking of BA and DDP did not produce a compound with additive therapeutic effects on glioblastoma cell lines in vitro. Nevertheless, the results of this study suggest that the precursor DE9B is an effective BA derivative for the treatment of glioblastoma in vitro.

Dissecting and rebuilding the glioblastoma microenvironment with engineered materials

Glioblastoma (GBM) is the most aggressive and common form of primary brain cancer. Several decades of research have provided great insight into GBM progression; however, the prognosis remains poor with a median patient survival time of ~ 15 months. The tumour microenvironment (TME) of GBM plays a crucial role in mediating tumour progression and thus is being explored as a therapeutic target. Progress in the development of treatments targeting the TME is currently limited by a lack of model systems that can accurately recreate the distinct extracellular matrix composition and anatomic features of the brain, such as the blood-brain barrier and axonal tracts. Biomaterials can be applied to develop synthetic models of the GBM TME to mimic physiological and pathophysiological features of the brain, including cellular and ECM composition, mechanical properties, and topography. In this Review, we summarize key features of the GBM microenvironment and discuss different strategies for the engineering of GBM TME models, including 2D and 3D models featuring chemical and mechanical gradients, interfaces and fluid flow. Finally, we highlight the potential of engineered TME models as platforms for mechanistic discovery and drug screening as well as preclinical testing and precision medicine.

Systematic Profiling of Alternative mRNA Splicing Signature for Predicting Glioblastoma Prognosis

Emerging evidence suggests that alternative splicing (AS) is modified in cancer and is associated with cancer progression. Systematic analysis of AS signature in glioblastoma (GBM) is lacking and is greatly needed. We profiled genome-wide AS events in 498 GBM patients in TCGA using RNA-seq data, and splicing network and prognostic predictor were built by integrated bioinformatics analysis. Among 45,610 AS events in 10,434 genes, we detected 1,829 AS events in 1,311 genes, and 1,667 AS events in 1,146 genes that were significantly associated with overall survival and disease-free survival of GBM patients, respectively. Five potential feature genes, S100A4, ECE2, CAST, ASPH, and LY6K, were discovered after network mining as well as correlation analysis between AS and gene expression, most of which were related to carcinogenesis and development. Multivariate survival model analysis indicated that these five feature genes could classify the prognosis at AS event and gene expression level. This report opens up a new avenue for exploration of the pathogenesis of GBM through AS, thus more precisely guiding clinical treatment and prognosis judgment.

Specific Glioma Prognostic Subtype Distinctions Based on DNA Methylation Patterns

DNA methylation is an important regulator of gene expression and may provide an important basis for effective glioma diagnosis and therapy. Here, we explored specific prognosis subtypes based on DNA methylation status using 653 gliomas from The Cancer Genome Atlas (TCGA) database. Five subgroups were distinguished by consensus clustering using 11,637 cytosines preceding a guanosine (CpGs) that significantly influenced survival. The specific DNA methylation patterns were correlated with age, tumor stage, and prognosis. Additionally, weighted gene co-expression network analysis (WGCNA) analysis of CpG sites revealed that 11 of them could distinguish the samples into high- and low-methylation groups and could classify the prognostic information of samples after cluster analysis of the training set samples using the hierarchical clustering algorithm. Similar results were obtained from the test set and 12 glioma patients. Moreover, in vitro experiments revealed an inverse relationship between methylation level and migration ability or insensitivity to temozolomide (or radiotherapy) of glioma cells based on the final prognostic predictor. Thus, these results suggested that the model constructed in this study could provide guidance for clinicians regarding the prognosis of various epigenetic subtypes.

Neural Stem Cells of the Subventricular Zone as the Origin of Human Glioblastoma Stem Cells. Therapeutic Implications

Human glioblastoma is the most aggressive type of primary malignant brain tumors. Standard treatment includes surgical resection followed by radiation and chemotherapy but it only provides short-term benefits and the prognosis of these brain tumors is still very poor. Glioblastomas contain a population of glioma stem cells (GSCs), with self-renewal ability, which are partly responsible for the tumor resistance to therapy and for the tumor recurrence after treatment. The human adult subventricular zone contains astrocyte-like neural stem cells (NSCs) that are probably reminiscent of the radial glia present in embryonic brain development. There are numerous molecules involved in the biology of subventricular zone NSCs that are also instrumental in glioblastoma development. These include cytoskeletal proteins, telomerase, tumor suppressor proteins, transcription factors, and growth factors. Interestingly, genes encoding these molecules are frequently mutated in glioblastoma cells. Indeed, it has been recently shown that NSCs in the subventricular zone are a potential cell of origin that contains the driver mutations of human glioblastoma. In this review we will describe common features between GSCs and subventricular zone NSCs, and we will discuss the relevance of this important finding in terms of possible future therapeutic strategies.

ARL3 is downregulated and acts as a prognostic biomarker in glioma

BACKGROUND

Glioma is the most common primary malignant brain tumor in adults with a poor prognosis. ARL3 is a member of the ARF family, and plays a key role in ciliary function and lipid-modified protein trafficking. ARL3 has been reported to be involved in ciliary diseases, in which it affects kidney and photoreceptor development. However, the functional role of ARL3 in cancer remains unknown. In this study, we aimed to explore ARL3 expression and its roles in glioma prognosis.

METHODS

RT-PCR and immunohistochemistry were performed to examine the expression level of ARL3 in glioma samples. Data from The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA) and Repository for Molecular Brain Neoplasia Data (REMBRANDT) databases were employed to investigate ARL3 expression and its roles in glioma prognosis. A nomogram for predicting 3- or 5-year survival was established using Cox proportional hazards regression. Finally, gene ontology (GO) analysis, gene set enrichment analysis (GSEA), and gene set variation analysis (GSVA) were performed to explore the biological function.

RESULTS

ARL3 expression was downregulated in glioma, and associated with poor prognosis in glioma patients. The C-indexes, areas under the ROC curve and calibration plots of the nomogram indicated an effective predictive performance for glioma patients. In addition, GO and pathway analyses suggested the involvement of ARL3 in angiogenesis and immune cell infiltration in the microenvironment.

CONCLUSIONS

Low ARL3 expression predicted poor prognosis and contributed to antiangiogenesis and the proportion of infiltrating immune cells in the GBM microenvironment. Thus, ARL3 may be a prognostic marker and therapeutic target for glioma.

Systemic Delivery of Monoclonal Antibodies to the Central Nervous System for Brain Tumor Therapy

As an essential component of immunotherapy, monoclonal antibodies (mAbs) have emerged as a class of powerful therapeutics for treatment of a broad range of diseases. For central nervous system (CNS) diseases, however, the efficacy remains limited due to their inability to enter the CNS. A platform technology is reported here that enables effective delivery of mAbs to the CNS for brain tumor therapy. This is achieved by encapsulating the mAbs within nanocapsules that contain choline and acetylcholine analogues; such analogues facilitate the penetration of the nanocapsules through the brain-blood barrier and the delivery of mAbs to tumor sites. This platform technology uncages the therapeutic power of mAbs for various CNS diseases that remain poorly treated.

Discovery of a pyrimidine compound endowed with antitumor activity

Recently, some synthetic nitrogen-based heterocyclic molecules, such as PJ34, have shown pronounced antitumor activity. Therefore, we designed and synthesized new derivatives characterized by a nitrogen-containing scaffold and evaluated their antiproliferative properties in tumor cells. We herein report the effects of three newly synthesized compounds on cell lines from three different human cancers: triple-negative breast cancer, colon carcinoma and glioblastoma. We found that two of these compounds did not affect proliferation, while the third significantly inhibited replication of the three cell lines. Moreover, this third molecule at 20 μM led to the upregulation of p21 and p27 and blockage of the cell cycle at G0/G1; in addition, it induced apoptosis in all three cell lines when used at higher concentrations (30-50 μM). The results demonstrate that this compound is a potent inhibitor of replication, an inducer of apoptosis and a negative regulator of cell cycle progression for cancer cells of different histotypes. Our data suggest a potential role for this new molecule as an interesting and powerful tool for new approaches in treating various cancers.