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Japanese Journal of Clinical Oncology Aug 2022Optimizing the management of elderly patients with glioblastoma is an ongoing task in neuro-oncology. The number of patients with this tumor type is gradually increasing... (Review)
Review
Optimizing the management of elderly patients with glioblastoma is an ongoing task in neuro-oncology. The number of patients with this tumor type is gradually increasing with the aging of the population. Although available data and practice recommendations remain limited, the current strategy is maximal safe surgical resection followed by radiotherapy in combination with temozolomide. However, survival is significantly worse than that in the younger population. Surgical resection provides survival benefit in patients with good performance status. Hypofractionated radiotherapy decreases toxicities while maintaining therapeutic efficacy, thus improving treatment adherence and subsequently leading to better quality of life. The intensity of these treatments should be balanced with patient-specific factors and consideration of quality of life. This review discusses the current optimal management in terms of efficacy and safety, as well as future perspectives.
Topics: Aged; Antineoplastic Agents, Alkylating; Brain Neoplasms; Glioblastoma; Humans; Quality of Life; Temozolomide
PubMed: 35552425
DOI: 10.1093/jjco/hyac075 -
International Journal of Molecular... Feb 2023Nitrosamines occur widespread in food, drinking water, cosmetics, as well as tobacco smoke and can arise endogenously. More recently, nitrosamines have been detected as... (Review)
Review
Nitrosamines occur widespread in food, drinking water, cosmetics, as well as tobacco smoke and can arise endogenously. More recently, nitrosamines have been detected as impurities in various drugs. This is of particular concern as nitrosamines are alkylating agents that are genotoxic and carcinogenic. We first summarize the current knowledge on the different sources and chemical nature of alkylating agents with a focus on relevant nitrosamines. Subsequently, we present the major DNA alkylation adducts induced by nitrosamines upon their metabolic activation by CYP450 monooxygenases. We then describe the DNA repair pathways engaged by the various DNA alkylation adducts, which include base excision repair, direct damage reversal by MGMT and ALKBH, as well as nucleotide excision repair. Their roles in the protection against the genotoxic and carcinogenic effects of nitrosamines are highlighted. Finally, we address DNA translesion synthesis as a DNA damage tolerance mechanism relevant to DNA alkylation adducts.
Topics: Nitrosamines; DNA Damage; Alkylation; DNA Repair; Alkylating Agents; DNA Adducts
PubMed: 36902118
DOI: 10.3390/ijms24054684 -
Lipids in Health and Disease Aug 2023Glioblastoma (GBM) is a highly aggressive and lethal brain tumor with limited treatment options, such as the chemotherapeutic agent, temozolomide (TMZ). However, many... (Review)
Review
Glioblastoma (GBM) is a highly aggressive and lethal brain tumor with limited treatment options, such as the chemotherapeutic agent, temozolomide (TMZ). However, many GBM tumors develop resistance to TMZ, which is a major obstacle to effective therapy. Recently, dysregulated lipid metabolism has emerged as an important factor contributing to TMZ resistance in GBM. The dysregulation of lipid metabolism is a hallmark of cancer and alterations in lipid metabolism have been linked to multiple aspects of tumor biology, including proliferation, migration, and resistance to therapy. In this review, we aimed to summarize current knowledge on lipid metabolism in TMZ-resistant GBM, including key metabolites and proteins involved in lipid synthesis, uptake, and utilization, and recent advances in the application of metabolomics to study lipid metabolism in GBM. We also discussed the potential of lipid metabolism as a target for novel therapeutic interventions. Finally, we highlighted the challenges and opportunities associated with developing these interventions for clinical use, and the need for further research to fully understand the role of lipid metabolism in TMZ resistance in GBM. Our review suggests that targeting dysregulated lipid metabolism may be a promising approach to overcome TMZ resistance and improve outcomes in patients with GBM.
Topics: Humans; Temozolomide; Glioblastoma; Antineoplastic Agents, Alkylating; Lipid Metabolism; Brain Neoplasms; Drug Resistance, Neoplasm; Cell Line, Tumor; Xenograft Model Antitumor Assays
PubMed: 37537607
DOI: 10.1186/s12944-023-01881-5 -
Current Opinion in Chemical Biology Oct 2023Per- and polysulfides are sulfane sulfur species produced inside living cells, in organisms as diverse as bacteria, plants and humans, but their biological roles remain... (Review)
Review
Per- and polysulfides are sulfane sulfur species produced inside living cells, in organisms as diverse as bacteria, plants and humans, but their biological roles remain to be fully understood. Unfortunately, due to their reactivity, per- and polysulfides are easily altered, interconverted or lost during the processing and analysis of biological material. Thus, all current analytical methods make use of alkylating agents, to quench reactivity of hydropersulfides and hydropolysulfides and also to prevent free thiols from attacking sulfur chains in hydropolysulfides and dialkyl polysulfides. However, recent findings reveal that alkylating agents can also destroy per- and polysulfides, to varying degrees, depending on the choice of alkylating agent. Here, we discuss the challenges associated with the alkylation of per- and polysulfides, the single most important step for their preservation and detection in biological samples.
Topics: Humans; Alkylating Agents; Sulfides; Sulfur; Sulfhydryl Compounds
PubMed: 37473483
DOI: 10.1016/j.cbpa.2023.102368 -
Biomedicine & Pharmacotherapy =... Sep 2023Glioblastoma (GBL) is the most common (60-70% of primary brain tumours) and the most malignant of the glial tumours. Although current therapies remain palliative, they... (Review)
Review
Glioblastoma (GBL) is the most common (60-70% of primary brain tumours) and the most malignant of the glial tumours. Although current therapies remain palliative, they have been proven to prolong overall survival. Within an optimal treatment regimen (incl. surgical resection, radiation therapy, and chemotherapy) temozolomide as the current anti-GBL first-line chemotherapeutic has increased the median overall survival to 14-15 months, and the percentage of patients alive at two years has been reported to rise from 10.4% to 26.5%. Though, the effectiveness of temozolomide chemotherapy is limited by the serious systemic, dose-related side effects. Therefore, the ponderation regarding novel treatment methods along with innovative formulations is crucial to emerging the therapeutic potential of the widely used drug simultaneously reducing the drawbacks of its use. Herein the complex temozolomide application restrictions present at different levels of therapy as well as, the currently proposed strategies aimed at reducing those limitations are demonstrated. Approaches increasing the efficacy of anti-GBL treatment are addressed. Our paper is focused on the most recent developments in the field of nano/biomaterials-based systems for temozolomide delivery and their functionalization towards more effective blood-brain-barrier crossing and/or tumour targeting. Appropriate designing accounting for the physical and chemical features of formulations along with distinct routes of administration is also discussed. In addition, considering the multiple resistance mechanisms, the molecular heterogeneity and the evolution of tumour the purposely selected delivery methods, the combined therapeutic approaches and specifically focused on GBL cells therapies are reviewed.
Topics: Humans; Temozolomide; Dacarbazine; Brain Neoplasms; Glioblastoma; Glioma; Antineoplastic Agents, Alkylating
PubMed: 37459661
DOI: 10.1016/j.biopha.2023.115174 -
In Vivo (Athens, Greece) 2021Care is often palliative when patients are not fit and complete resection of glioblastomas cannot be achieved. This study aimed to identify predictors of survival after...
BACKGROUND/AIM
Care is often palliative when patients are not fit and complete resection of glioblastomas cannot be achieved. This study aimed to identify predictors of survival after palliative radiotherapy.
PATIENTS AND METHODS
Thirty-one patients irradiated after biopsy or incomplete resection of primary glioblastoma were retrospectively analyzed. Median total dose, dose per fraction and equivalent dose in 2 Gy fractions (EQD2) were 45.0 Gy, 3.0 Gy and 46.0 Gy, respectively. Median number of fractions was 15, median treatment time 3 weeks. Ten patients received temozolomide. Six factors were evaluated for survival including location of glioblastoma, Karnofsky performance score (KPS), gender, age, EQD2 and temozolomide.
RESULTS
KPS ≥60 showed a trend for improved survival (p=0.141). For other factors including EQD2, no significant association with survival was found.
CONCLUSION
Patients with a KPS ≤50 have a poor survival prognosis and appear good candidates for short-course radiotherapy. Selected patients with better KPS may be considered for more aggressive treatments.
Topics: Antineoplastic Agents, Alkylating; Brain Neoplasms; Glioblastoma; Humans; Prognosis; Retrospective Studies; Temozolomide
PubMed: 33402500
DOI: 10.21873/invivo.12282 -
International Journal of Circumpolar... Dec 2023Glioblastoma (GBM), WHO grade IV, is the most common primary malignant brain tumour among adults with a devastating overall survival of 14-22 months. Standard...
Glioblastoma (GBM), WHO grade IV, is the most common primary malignant brain tumour among adults with a devastating overall survival of 14-22 months. Standard treatment of GBM includes maximum safe resection, radiotherapy plus concomitant and adjuvant temozolomide (TMZ), given over a period of approximately 9 months. Treatment and follow-up for Greenlandic patients with GBM are managed at Rigshospitalet (RH), Copenhagen. Greenlandic GBM patients, therefore, travel back and forth to RH, often unaccompanied, and challenged by cognitive failure or other symptoms from their disease and/or treatment. Few Greenlandic patients are diagnosed with GBM annually, but considering the poor prognosis and short remaining lifespan, it would be preferable to limit their travels. TMZ is administrated as capsules. Health personnel at Queen Ingrid's Hospital (DIH), Nuuk, are trained in treating other oncological diseases and handling side effects. Hence, it could be investigated whether administration of adjuvant TMZ at DIH could be feasible after personnel education as well as economic consideration and compensation, in close collaboration with neuro oncologists at RH. In this article, we describe the Greenlandic cancer treatment, and the typical workflow from diagnosis of GBM to treatment to progression.
Topics: Adult; Humans; Glioblastoma; Antineoplastic Agents, Alkylating; Dacarbazine; Chemotherapy, Adjuvant; Brain Neoplasms; Temozolomide
PubMed: 37992407
DOI: 10.1080/22423982.2023.2285077 -
Acta Haematologica 2020The gut microbiota plays a significant role in health and disease, including cancer development and treatment. The importance of the gut microbiota in the efficacy and... (Review)
Review
The gut microbiota plays a significant role in health and disease, including cancer development and treatment. The importance of the gut microbiota in the efficacy and toxicity of novel therapies and immunotherapy is increasingly recognized. Plasma cells in multiple myeloma have the potential to survive in the gastrointestinal tract for long periods of time. The nature of the gut microbiota impacts the degree of antigen stimulation of these cells and may play a role in mutation development and clonal evolution. Furthermore, myeloma therapies such as proteasome inhibitors and alkylating agents, commonly used to treat patients, are frequently associated with gastrointestinal adverse events. Herein we review the gut microbiota and its role in hematopoiesis, pathogenesis of myeloma, and efficacy/toxicity of anti-myeloma therapies.
Topics: Antineoplastic Agents, Alkylating; Cytokines; Gastrointestinal Microbiome; Humans; Multiple Myeloma; NF-kappa B; Plasma Cells; Proteasome Inhibitors; Signal Transduction
PubMed: 31311009
DOI: 10.1159/000500976 -
Journal of Natural Products Jan 2022Glioblastoma multiforme (GBM) is the most aggressive cancer originating in the brain, with a median survival of 12 months. Most patients do not respond to or develop...
Glioblastoma multiforme (GBM) is the most aggressive cancer originating in the brain, with a median survival of 12 months. Most patients do not respond to or develop resistance to the only effective chemotherapeutic drug, temozolomide (TMZ), used to treat gliomas. Novel treatment methods are critically needed. Cyclotides are plant peptides that may be promising adjuvants to TMZ chemotherapy. They exhibit antitumor activity and chemosensitize cells to doxorubicin in breast cancer studies. During this research, we optimized cyclotide isolation techniques, and several cyclotides (CyO2, CyO13, kalata B1, and varv peptide A) exhibited dose-dependent cytotoxicity in MTT assays with IC values of 2.15-7.92 μM against human brain astrocytoma cells (U-87 MG) and human bone marrow derived neuroblastoma cells (SH-SY5Y). CyO2 and varv peptide A increased TMZ-induced cell death in U-87 MG cultures alone and when coexposed with CyO2 or varv peptide A plus TMZ. Phase contrast microscopy of glioblastoma cells exposed to cyclotides alone and coexposed to TMZ indicated shrunken, granular cells with blebbing, and the most pronounced effects were observed with coexposure treatments of cyclotides and TMZ. Cumulative results provide the proof-of-concept that cyclotides may enhance TMZ chemotherapy, and pharmacokinetic investigations of cyclotides are warranted with respect to GBM.
Topics: Animals; Antineoplastic Agents, Alkylating; Brain Neoplasms; Cell Line, Tumor; Cell Survival; Cyclotides; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Glioblastoma; Humans; Mice; Proof of Concept Study; Temozolomide; Xenograft Model Antitumor Assays
PubMed: 35044783
DOI: 10.1021/acs.jnatprod.1c00595 -
Frontiers in Bioscience (Landmark... Sep 2023O6-methylguanine-DNA-methyltransferase (MGMT) is a DNA repair enzyme, which reverses the alkylation of guanine O6 through directtransfer of the methyl group, maintains... (Review)
Review
O6-methylguanine-DNA-methyltransferase (MGMT) is a DNA repair enzyme, which reverses the alkylation of guanine O6 through directtransfer of the methyl group, maintains the gene stability and avoids tumor occurrence. Studies have shown that gene methylation, polymorphism and protein expression are involved in the process of various tumor development, such as colon cancer, gastric carcinoma, etc. gene promotes methylation, protein expression and enzyme activity from various tissues, which resultsin different effects on the prognosis of patients. MGMT promoter methylation is a positive factor for the prognosis of Glioblastoma (GBM), which can prolong overall survival and progression-free survival, reduce the resistance of tumor cells to temozolomide treatment, and improve the prognosis. The treatment of tumors based on MGMT focuses on three aspects: targeting MGMT to increase the sensitivity of alkylated drug therapy in tumors, immunotherapy combined with alkylated agents on tumor treatment, and treatment for patients with MGMT promoter non-methylation. Similarly, a number of studies have targeted MGMT to reduce alkylated agent resistance in other systems. Although numerous studies on MGMT in tumors have been reported, there are problems that need to be solved, such as selection and consensus of MGMT promoter methylation detection methods (CpG detection sites, cut-off value) and the treatment of MGMT non-methylated GBM patients, especially elderly patients. In this review, we describe the regulation of MGMT expression and its role inchemotherapy, especially in gliomas. Further studies exploring new methods targeting MGMT with better curative effect and less toxicity are advocated. We anticipate that these developments will be progressive and sufficiently used for clinical application.
Topics: Humans; Antineoplastic Agents, Alkylating; Brain Neoplasms; Dacarbazine; DNA; DNA Methylation; DNA Repair Enzymes; Glioblastoma; O(6)-Methylguanine-DNA Methyltransferase
PubMed: 37796680
DOI: 10.31083/j.fbl2809197