Advantages and drawbacks of dexamethasone in glioblastoma multiforme

Immunotherapy for glioblastoma: current state, challenges, and future perspectives

Glioblastoma (GBM) is an aggressive and lethal type of brain tumor in human adults. The standard of care offers minimal clinical benefit, and most GBM patients experience tumor recurrence after treatment. In recent years, significant advancements have been made in the development of novel immunotherapies or other therapeutic strategies that can overcome immunotherapy resistance in many advanced cancers. However, the benefit of immune-based treatments in GBM is limited because of the unique brain immune profiles, GBM cell heterogeneity, and immunosuppressive tumor microenvironment. In this review, we present a detailed overview of current immunotherapeutic strategies and discuss the challenges and potential molecular mechanisms underlying immunotherapy resistance in GBM. Furthermore, we provide an in-depth discussion regarding the strategies that can overcome immunotherapy resistance in GBM, which will likely require combination therapies.

Recent update on anti-tumor mechanisms of valproic acid in glioblastoma multiforme

Glioblastoma multiforme (GBM) is a malignant tumor of the brain that is considered to be incurable. Currently, surgical removal of tumors, chemotherapy with temozolomide, and radiation treatment remain established options for treatment. Nevertheless, the prognosis of those with GBM continues to be poor owing to the inherent characteristics of tumor growth and spread, as well as the resistance to treatment. To effectively deal with the present circumstances, it is vital to do extensive study to understand GBM thoroughly. The following piece provides a concise overview of the most recent advancements in using valproic acid, an antiseizure medication licensed by the FDA, for treating GBM. In this review, we outline the most recent developments of valproic acid in treating GBM, as well as its fundamental mechanisms and practical consequences. Our goal is to provide a greater understanding of the clinical use of valproic acid as a potential therapeutic agent for GBM.

Fibrotic response to anti-CSF-1R therapy potentiates glioblastoma recurrence

Glioblastoma recurrence is currently inevitable despite extensive standard-of-care treatment. In preclinical studies, an alternative strategy of targeting tumor-associated macrophages and microglia through CSF-1R inhibition was previously found to regress established tumors and significantly increase overall survival. However, recurrences developed in ∼50% of mice in long-term studies, which were consistently associated with fibrotic scars. This fibrotic response is observed following multiple anti-glioma therapies in different preclinical models herein and in patient recurrence samples. Multi-omics analyses of the post-treatment tumor microenvironment identified fibrotic areas as pro-tumor survival niches that encapsulated surviving glioma cells, promoted dormancy, and inhibited immune surveillance. The fibrotic treatment response was mediated by perivascular-derived fibroblast-like cells via activation by transforming growth factor β (TGF-β) signaling and neuroinflammation. Concordantly, combinatorial inhibition of these pathways inhibited treatment-associated fibrosis, and significantly improved survival in preclinical trials of anti-colony-stimulating factor-1 receptor (CSF-1R) therapy.

Advances in gene therapy for high-grade glioma: a review of the clinical evidence

INTRODUCTION

High-grade glioma (HGG) is one of the most deadly and difficult cancers to treat. Despite intense research efforts, there has not been a significant breakthrough in treatment outcomes since the early 2000's. Anti-glioma gene therapy has demonstrated promise in preclinical studies and is under investigation in numerous clinical trials.

AREAS COVERED

This manuscript reviews the current landscape of clinical trials exploring gene therapy treatment of HGG. Using information from clinicaltrials.gov, all trials initiated within the past 5 years (2018-2023) as well as other important trials were cataloged and reviewed. This review discusses trial details, innovative methodologies, and concurrent pharmacological interventions. The review also delves into the subtypes of gene therapy used, trends over time, and future directions.

EXPERT OPINION

Trials are in the early stages (phase I or II), and there are reports of clinical efficacy in published results. Synergistic effects utilizing immunotherapy within or alongside gene therapy are emerging as a promising avenue for future breakthroughs. Considerable heterogeneity exists across trials concerning administration route, vector selection, drug combinations, and intervention timing. Earlier intervention in newly diagnosed HGG and avoidance of corticosteroids may improve efficacy in future trials. The results from ongoing trials demonstrate promising potential for molding the future landscape of HGG care.

In vivo evaluation of efficacy and safety of Coagulansin-A in treating arthritis

The current study aimed to determine the safety and efficacy of Coag-A through in vivo analysis in CFA induced mice model. Treatment of CFA induced arthritis in mice with Coagulansin-A (10 mg/kg i.p. daily for 28 days), a withanolide obtained from Withania coagulans, as well as standard drug treatment with Dexamethasone (5 mg/kg i.p) was provided. The effect of Coag-A on body weight, relative organ weight, hematology, serum biochemistry, survival rate, oxidative stress markers, and antioxidant enzymes was evaluated. The liver and kidney histopathology were also assessed to ascertain its safety profile. Treatment of arthritic mice with Coag-A considerably improved body weight, relative organ weight of liver, kidney, and spleen, ameliorated hematology and serum biochemistry, and increased survival and antioxidant potential. Coag-A was found to be safer with fewer adverse effects showing hepato-protective, nephroprotective, and anti-inflammatory effect. It also significantly (p < 0.001) improved histopathology of CFA-induced mice when compared with Dexa. In conclusion, compared to dexamethasone, Coag-A has demonstrated a greater therapeutic benefit and fewer side effects in the treatment of arthritis against the CFA-induced model.

Harnessing the capacity of phytochemicals to enhance immune checkpoint inhibitor therapy of cancers: A focus on brain malignancies

Brain cancers, particularly glioblastoma multiforme (GBM), are challenging health issues with frequent unmet aspects. Today, discovering safe and effective therapeutic modalities for brain tumors is among the top research interests. Immunotherapy is an emerging area of investigation in cancer treatment. Since immune checkpoints play fundamental roles in repressing anti-cancer immunity, diverse immune checkpoint inhibitors (ICIs) have been developed, and some monoclonal antibodies have been approved clinically for particular cancers; nevertheless, there are significant concerns regarding their efficacy and safety in brain tumors. Among the various tools to modify the immune checkpoints, phytochemicals show good effectiveness and excellent safety, making them suitable candidates for developing better ICIs. Phytochemicals regulate multiple immunological checkpoint-related signaling pathways in cancer biology; however, their efficacy for clinical cancer immunotherapy remains to be established. Here, we discussed the involvement of immune checkpoints in cancer pathology and summarized recent advancements in applying phytochemicals in modulating immune checkpoints in brain tumors to highlight the state-of-the-art and give constructive prospects for future research.

Exploring Gut Microbiota Alterations with Trimethoprim-Sulfamethoxazole and Dexamethasone in a Humanized Microbiome Mouse Model

Along with the standard therapies for glioblastoma, patients are commonly prescribed trimethoprim-sulfamethoxazole (TMP-SMX) and dexamethasone for preventing infections and reducing cerebral edema, respectively. Because the gut microbiota impacts the efficacy of cancer therapies, it is important to understand how these medications impact the gut microbiota of patients. Using mice that have been colonized with human microbiota, this study sought to examine how TMP-SMX and dexamethasone affect the gut microbiome. Two lines of humanized microbiota (HuM) Rag1-/- mice, HuM1Rag and HuM2Rag, were treated with either TMP-SMX or dexamethasone via oral gavage once a day for a week. Fecal samples were collected pre-treatment (pre-txt), one week after treatment initiation (1 wk post txt), and three weeks post-treatment (3 wk post txt), and bacterial DNA was analyzed using 16S rRNA-sequencing. The HuM1Rag mice treated with TMP-SMX had significant shifts in alpha diversity, beta diversity, and functional pathways at all time points, whereas in the HuM2Rag mice, it resulted in minimal changes in the microbiome. Likewise, dexamethasone treatment resulted in significant changes in the microbiome of the HuM1Rag mice, whereas the microbiome of the HuM2Rag mice was mostly unaffected. The results of our study show that routine medications used during glioblastoma treatment can perturb gut microbiota, with some microbiome compositions being more sensitive than others, and these treatments could potentially affect the overall efficacy of standard-of-care therapy.

Impact of glioma peritumoral edema, tumor size, and tumor location on alternating electric fields (AEF) therapy in realistic 3D rat glioma models: a computational study

Objective.Alternating electric fields (AEF) therapy is a treatment modality for patients with glioblastoma. Tumor characteristics such as size, location, and extent of peritumoral edema may affect the AEF strength and distribution. We evaluated the sensitivity of the AEFs in a realistic 3D rat glioma model with respect to these properties.Approach.The electric properties of the peritumoral edema were varied based on calculated and literature-reported values. Models with different tumor composition, size, and location were created. The resulting AEFs were evaluated in 3D rat glioma models.Main results.In all cases, a pair of 5 mm diameter electrodes induced an average field strength >1 V cm-1. The simulation results showed that a negative relationship between edema conductivity and field strength was found. As the tumor core size was increased, the average field strength increased while the fraction of the shell achieving >1.5 V cm-1decreased. Increasing peritumoral edema thickness decreased the shell's mean field strength. Compared to rostrally/caudally, shifting the tumor location laterally/medially and ventrally (with respect to the electrodes) caused higher deviation in field strength.Significance.This study identifies tumor properties that are key drivers influencing AEF strength and distribution. The findings might be potential preclinical implications.

An autologous ex vivo model for exploring patient-specific responses to viro-immunotherapy in glioblastoma

Oncolytic virus (OV) clinical trials have demonstrated remarkable efficacy in subsets of patients with glioblastoma (GBM). However, the lack of tools to predict this response hinders the advancement of a more personalized application of OV therapy. In this study, we characterize an ex vivo co-culture system designed to examine the immune response to OV infection of patient-derived GBM neurospheres in the presence of autologous peripheral blood mononuclear cells (PBMCs). Co-culture conditions were optimized to retain viability and functionality of both tumor cells and PBMCs, effectively recapitulating the well-recognized immunosuppressive effects of GBM. Following OV infection, we observed elevated secretion of pro-inflammatory cytokines and chemokines, including interferon γ, tumor necrosis factor α, CXCL9, and CXCL10, and marked changes in immune cell activation markers. Importantly, OV treatment induced unique patient-specific immune responses. In summary, our co-culture platform presents an avenue for personalized screening of viro-immunotherapies in GBM, offering promise as a potential tool for future patient stratification in OV therapy.

The immunological landscape of peripheral blood in glioblastoma patients and immunological consequences of age and dexamethasone treatment

Background

Glioblastomas manipulate the immune system both locally and systemically, yet, glioblastoma-associated changes in peripheral blood immune composition are poorly studied. Age and dexamethasone administration in glioblastoma patients have been hypothesized to limit the effectiveness of immunotherapy, but their effects remain unclear. We compared peripheral blood immune composition in patients with different types of brain tumor to determine the influence of age, dexamethasone treatment, and tumor volume.

Methods

High-dimensional mass cytometry was used to characterise peripheral blood mononuclear cells of 169 patients with glioblastoma, lower grade astrocytoma, metastases and meningioma. We used blood from medically-refractory epilepsy patients and healthy controls as control groups. Immune phenotyping was performed using FlowSOM and t-SNE analysis in R followed by supervised annotation of the resulting clusters. We conducted multiple linear regression analysis between intracranial pathology and cell type abundance, corrected for clinical variables. We tested correlations between cell type abundance and survival with Cox-regression analyses.

Results

Glioblastoma patients had significantly fewer naive CD4+ T cells, but higher percentages of mature NK cells than controls. Decreases of naive CD8+ T cells and alternative monocytes and an increase of memory B cells in glioblastoma patients were influenced by age and dexamethasone treatment, and only memory B cells by tumor volume. Progression free survival was associated with percentages of CD4+ regulatory T cells and double negative T cells.

Conclusion

High-dimensional mass cytometry of peripheral blood in patients with different types of intracranial tumor provides insight into the relation between intracranial pathology and peripheral immune status. Wide immunosuppression associated with age and pre-operative dexamethasone treatment provide further evidence for their deleterious effects on treatment with immunotherapy.

Prolonged use of temozolomide leads to increased anxiety and decreased content of aggrecan and chondroitin sulfate in brain tissues of aged rats

Chemotherapy with temozolomide (TMZ) is an essential part of anticancer therapy used for malignant tumors (mainly melanoma and glioblastoma); however, the long-term effects on patient health and life quality are not fully investigated. Considering that tumors often occur in elderly patients, the present study was conducted on long-term (4 months) treatment of adult Wistar rats (9 months old, n=40) with TMZ and/or dexamethasone (DXM) to investigate potential behavioral impairments or morphological and molecular changes in their brain tissues. According to the elevated plus maze test, long-term use of TMZ affected the anxiety of the adult Wistar rats, although no significant deterioration of brain morphology or cellular composition of the brain tissue was revealed. The expression levels of all studied heparan sulfate (HS) proteoglycans (HSPGs) (syndecan-1, syndecan-3, glypican-1 and HSPG2) and the majority of the studied chondroitin sulfate (CS) proteoglycans (CSPGs) (decorin, biglycan, lumican, brevican, neurocan aggrecan, versican, Cspg4/Ng2, Cspg5 and phosphacan) were not affected by TMZ/DXM, except for neurocan and aggrecan. Aggrecan was the most sensitive proteoglycan to TMZ/DXM treatment demonstrating downregulation of its mRNA and protein levels following TMZ (-10-fold), DXM (-45-fold) and TMZ-DXM (-80-fold) treatment. HS content was not affected by TMZ/DXM treatment, whereas CS content was decreased 1.5-2.5-fold in the TMZ- and DXM-treated brain tissues. Taken together, the results demonstrated that treatment of adult Wistar rats with TMZ had long-term effects on the brain tissues, such as decreased aggrecan core protein levels and CS chain content and increased anxiety of the experimental animals.

Palliative Care and Care Partner Support in Neuro-oncology

ABSTRACT

The journey for a patient with a brain tumor and their loved ones can be extremely challenging due to the high burden of physical symptoms and the emotional distress caused by the diagnosis. Optimizing quality of life by addressing symptoms and reducing this emotional distress can improve treatment tolerance and outcomes and alleviate care partner distress and burden. Symptoms in patients with central nervous system (CNS) tumors can vary in onset and intensity, ranging from headaches, seizures, and focal weakness to emotional distress and cognitive dysfunction. Additionally, care partners may demonstrate distress due to the high burden of care and need appropriate support structures and access to resources to alleviate this stress. Evidence-based recommendations are unfortunately limited given the lack of high-quality research in this area, but patients living with CNS tumors and their loved ones can benefit from early and routine symptom identification and management, compassionate and transparent communication, and practical guidance for the future. These principles are part of palliative care, a field of medicine focused on alleviating suffering in patients with serious, chronic illness. Clinicians involved in the care of patients with CNS tumors must be educated in these important primary palliative care principles. This article focuses on key symptom management, strategies for high-quality communication, a discussion of advance care planning, and an overview of end-of-life care.

CXCR2-Blocking Has Context-Sensitive Effects on Rat Glioblastoma Cell Line Outgrowth (S635) in an Organotypic Rat Brain Slice Culture Depending on Microglia-Depletion (PLX5622) and Dexamethasone Treatment

In glioblastoma (GBM), the interplay of different immune cell subtypes, cytokines, and/or drugs shows high context-dependencies. Interrelations between the routinely applied dexamethasone (Dex) and microglia remain elusive. Here, we exploited rat organotypic brain slice co-cultures (OBSC) to examine the effects on a rat GBM cell line (S635) outgrowth resulting from the presence of Dex and pretreatment with the colony-stimulating factor receptor 1 (CSF1-R) inhibitor PLX5622: in native OBSC (without PLX5622-pretreatment), a diminished S635 spheroid outgrowth was observable, whereas Dex-treatment enhanced outgrowth in this condition compared to PLX5622-pretreated OBSC. Screening the supernatants of our model with a proteome profiler, we found that CXCL2 was differentially secreted in a Dex- and PLX5622-dependent fashion. To analyze causal interrelations, we interrupted the CXCL2/CXCR2-axis: in the native OBSC condition, CXCR2-blocking resulted in increased outgrowth, in combination with Dex, we found potentiated outgrowth. No effect was found in the PLX5622-pretreated. Our method allowed us to study the influence of three different factors-dexamethasone, PLX5622, and CXCL2-in a well-controlled, simplified, and straight-forward mechanistic manner, and at the same time in a more realistic ex vivo scenario compared to in vitro studies. In our model, we showed a GBM outgrowth enhancing synergism between CXCR2-blocking and Dex-treatment in the native condition, which was levelled by PLX5622-pretreatment.

Synergistic effects of flavonoids and paclitaxel in cancer treatment: a systematic review

Paclitaxel is a natural anticancer compound with minimal toxicity, the capacity to stabilize microtubules, and high efficiency that has remained the standard of treatment alongside platinum-based therapy as a remedy for a variety of different malignancies. In contrast, polyphenols such as flavonoids are also efficient antioxidant and anti-inflammatory and have now been shown to possess potent anticancer properties. Therefore, the synergistic effects of paclitaxel and flavonoids against cancer will be of interest. In this review, we use a Boolean query to comprehensively search the well-known Scopus database for literature research taking the advantage of paclitaxel and flavonoids simultaneously while treating various types of cancer. After retrieving and reviewing the intended investigations based on the input keywords, the anticancer mechanisms of flavonoids and paclitaxel and their synergistic effects on different targets raging from cell lines to animal models are discussed in terms of the corresponding involved signaling transduction. Most studies demonstrated that these signaling pathways will induce apoptotic / pro-apoptotic proteins, which in turn may activate several caspases leading to apoptosis. Finally, it can be concluded that the results of this review may be beneficial in serving as a theoretical foundation and reference for future studies of paclitaxel synthesis, anticancer processes, and clinical applications involving different clinical trials.

Alpha-Lipoic Acid, Auraptene, and Particularly Their Combination Prevent the Metastasis of U87 Human Glioblastoma Cells

Background

The primary malignant brain tumor glioblastoma multiforme (GBM) is most commonly detected in individuals over 60 years old. The standard therapeutic approach for GBM is radiotherapy combined with temozolomide. Recently, herbal products, such as alpha-lipoic acid (ALA) and auraptene (AUR), have shown promising anticancer effects on various cancer cells and animal models. However, it is not well understood how ALA, AUR, and their combination in GBM work to combat cancer. Thus, the purpose of this study was to investigate the antimetastatic effects of the ALA-AUR combination on U87 human glioblastoma cells.

Methods

The inhibitory effects of ALA, AUR, and the ALA/AUR combination on the migration and metastasis of U87 cells were evaluated using a wound healing test and gelatin zymography. The expression levels of matrix metalloproteinase MMP-2 and MMP-9 were assessed at the transcriptional and translational levels using quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting, respectively.

Results

Our findings revealed that combination therapy reduced cell migration and metastasis, which was indicated by the reduction in MMP-2/-9 expression both at mRNA and protein levels, as well as their enzymatic activity in U87 cells.

Conclusion

This study demonstrated that the combination of ALA and AUR effectively inhibited the migration and metastasis of U87 cells. Thus, given their safety and favorable specifications, the combination of these drugs can be a promising candidate for GBM treatment as primary or adjuvant therapy.

Dexamethasone Inhibits Heparan Sulfate Biosynthetic System and Decreases Heparan Sulfate Content in Orthotopic Glioblastoma Tumors in Mice

Glioblastoma (GB) is an aggressive cancer with a high probability of recurrence, despite active chemoradiotherapy with temozolomide (TMZ) and dexamethasone (DXM). These systemic drugs affect the glycosylated components of brain tissue involved in GB development; however, their effects on heparan sulfate (HS) remain unknown. Here, we used an animal model of GB relapse in which SCID mice first received TMZ and/or DXM (simulating postoperative treatment) with a subsequent inoculation of U87 human GB cells. Control, peritumor and U87 xenograft tissues were investigated for HS content, HS biosynthetic system and glucocorticoid receptor (GR, Nr3c1). In normal and peritumor brain tissues, TMZ/DXM administration decreased HS content (5-6-fold) but did not affect HS biosynthetic system or GR expression. However, the xenograft GB tumors grown in the pre-treated animals demonstrated a number of molecular changes, despite the fact that they were not directly exposed to TMZ/DXM. The tumors from DXM pre-treated animals possessed decreased HS content (1.5-2-fold), the inhibition of HS biosynthetic system mainly due to the -3-3.5-fold down-regulation of N-deacetylase/N-sulfotransferases (Ndst1 and Ndst2) and sulfatase 2 (Sulf2) expression and a tendency toward a decreased expression of the GRalpha but not the GRbeta isoform. The GRalpha expression levels in tumors from DXM or TMZ pre-treated mice were positively correlated with the expression of a number of HS biosynthesis-involved genes (Ext1/2, Ndst1/2, Glce, Hs2st1, Hs6st1/2), unlike tumors that have grown in intact SCID mice. The obtained data show that DXM affects HS content in mouse brain tissues, and GB xenografts grown in DXM pre-treated animals demonstrate attenuated HS biosynthesis and decreased HS content.

Urolithin B loaded in cerium oxide nanoparticles enhances the anti-glioblastoma effects of free urolithin B in vitro

Glioblastoma multiforme (GBM) is the most aggressive kind of malignant primary brain tumor in humans. Given the limitation of Conventional therapeutic strategy, the development of nanotechnology and natural product therapy seems to be an effective method enhancing the prognosis of GBM patients. In this research, cell viability, mRNA expressions of various apoptosis-related genes apoptosis, and generation of reactive oxygen species (ROS) in human U-87 malignant GBM cell line (U87) treated with Urolithin B (UB) and CeO₂-UB. Unlike CeO₂-NPs, both UB and CeO₂-UB caused a dose-dependent decrease in the viability of U87 cells. The half-maximal inhibitory concentration values of UB and CeO₂-UB were 315 and 250 μM after 24 h, respectively. Moreover, CeO₂-UB exerted significantly higher effects on U87 viability, P53 expression, and ROS generation. Furthermore, UB and CeO2-UB increased the accumulation of U87 cells in the SUB-G1 population, decreased the expression of cyclin D1, and increased the Bax/Bcl2 ratio expression. Collectively, these data indicate that CeO₂-UB exhibited more substantial anti-GBM effects than UB. Although further in vivo investigations are needed, these results proposed that CeO₂-NPs could be utilized as a potential novel anti-GBM agent after further studies.

The Effect of Steroid and Mannitol Combination Treatment on Postoperative Rehabilitation of Multiple Metacarpal Bone Fractures

Background and Objectives: The expedient resolution of postoperative soft tissue edema is particularly important in hand surgery. Prolonged edema and pain become an obstacle to postoperative rehabilitation, delay return to daily life, and in severe cases, lead to a permanent decrease in range of motion. Based on the common physiology between postoperative hand swelling and complex regional pain syndrome (CRPS), we sought to determine if postoperative mannitol and steroid administration to multiple metacarpal bone fracture patients effectively reduces hand swelling and pain and is beneficial for hand rehabilitation. Materials and Methods: From March 2015 to February 2019, 21 patients who received closed pinning for multiple metacarpal fractures were included in a retrospective cohort study. The control group (n = 11) underwent a routine recovery, while the treatment group (n = 10) received dexamethasone and mannitol injections for five days postoperatively. Serial changes in the degree of pain and fingertip-to-palm distance (FPD) were measured in both groups. The duration from surgery to the initiation of rehabilitation and time to full grip was also compared. Results: Compared to the control, the treatment group showed a faster alleviation of pain scores from the postoperative fifth day (2.91 versus 1.80, p = 0.013), and faster recovery of FPD from postoperative two weeks (3.27 versus 1.90, p = 0.002). Time to physical therapy initiation (6.73 versus 3.80 days, p = 0.002) and full grip achievement (42.46 versus 32.70 days, p = 0.002) were also faster in the treatment group. Conclusions: The steroid-mannitol combination treatment for multiple metacarpal bone fracture patients in the acute postoperative phase promoted the reduction of hand edema and pain, leading to the earlier initiation of physical therapy, rapid improvement in joint motion, and faster achievement of full grip.

Psidium guajava induces cytotoxicity in human malignant glioblastoma cell line: Role of reactive oxygen species

One of the deadliest types of CNS primary brain cancers is glioblastoma multiforme (GBM), and the survival rate of patients is about 7.2%. The standard treatment for GBM is surgical interventions followed by temozolomide. We investigated for the first time, the cytotoxic impacts of Psidium guajava (P. guajava) on the U87 GBM cell line. We measured cell toxicity through the MTT test following 24 h, 48 h, and 72 h treatment with different concentrations of fruit and seed hydroalcoholic extracts of P. guajava (25-400 μg/ml). Lipid peroxidation assay, reactive oxygen species (ROS) production, and apoptosis rate were evaluated 24 h after treatment by extracts of P. guajava. Moreover, to determine the Bax/Bcl-2 and NF-κB genes expression, we performed a real-time polymerase chain reaction (RT-PCR). Our finding demonstrated that 50-400 μg/ml of P. guajava extracts dose-dependently decreased the viability of U87 cells. Also, treatment by extracts increased lipid peroxidation, ROS production, and apoptosis in a dose-dependent manner. Moreover, the RT-PCR demonstrated an up-regulation in Bax\Bcl-2 and NF-κB. Thus, P. guajava inhibited the proliferation of U87 GBM cells and increased apoptosis probably through Bax/Bcl-2 and NF-κB regulation.

Recent advances in glioblastoma multiforme therapy: A focus on autophagy regulation

Despite conventional treatment options including chemoradiation, patients with the most aggressive primary brain tumor, glioblastoma multiforme (GBM), experience an average survival time of less than 15 months. Regarding the malignant nature of GBM, extensive research and discovery of novel treatments are urgently required to improve the patients' prognosis. Autophagy, a crucial physiological pathway for the degradation and recycling of cell components, is one of the exciting targets of GBM studies. Interventions aimed at autophagy activation or inhibition have been explored as potential GBM therapeutics. This review, which delves into therapeutic techniques to block or activate autophagy in preclinical and clinical research, aims to expand our understanding of available therapies battling GBM.