-
IUBMB Life Mar 2022Cancer accounted for nearly 10 million deaths in 2020 and is the second leading cause of death worldwide. The chemotherapeutic agents that are in clinical practice... (Review)
Review
Cancer accounted for nearly 10 million deaths in 2020 and is the second leading cause of death worldwide. The chemotherapeutic agents that are in clinical practice possess a broad range of severe adverse effects towards vital organs which emphasizes the importance of the discovery of new therapeutic agents or repurposing of existing drugs for the treatment of human cancers. Pyrimethamine is an antiparasitic drug used for the treatment of malaria and toxoplasmosis with a well-documented excellent safety profile. In the last 5 years, numerous efforts have been made to explore the anticancer potential of pyrimethamine in in vitro and in vivo preclinical models and to repurpose it as an anticancer agent. The studies have demonstrated that pyrimethamine inhibits oncogenic proteins such as STAT3, NF-κB, DX2, MAPK, DHFR, thymidine phosphorylase, telomerase, and many more in a different types of cancer models. Moreover, pyrimethamine has been reported to work in synergy with other anticancer agents, such as temozolomide, to induce apoptosis of tumor cells. Recently, the results of phase-1/2 clinical trials demonstrated that pyrimethamine administration reduces the expression of STAT3 signature genes in tumor tissues of chronic lymphocytic leukemia patients with a good therapeutic response. In the present article, we have reviewed most of the published articles related to the antitumor effects of pyrimethamine in malignancies of breast, liver, lung, skin, ovary, prostate, pituitary, and leukemia in in vitro and in vivo settings. We have also discussed the pharmacokinetic profile and results of clinical trials obtained after pyrimethamine treatment. From these studies, we believe that pyrimethamine has the potential to be repurposed as an anticancer drug.
Topics: Antineoplastic Agents; Apoptosis; Female; Humans; Neoplasms; Pyrimethamine; Temozolomide
PubMed: 34921584
DOI: 10.1002/iub.2590 -
Neurology India 2022
Topics: Antineoplastic Agents, Alkylating; Cell Line, Tumor; Glioblastoma; Humans; Melanoma; Skin Neoplasms; Temozolomide
PubMed: 35263941
DOI: 10.4103/0028-3886.338725 -
CNS Neuroscience & Therapeutics Nov 2023Glioblastoma multiforme (GBM) is the deadliest glioma and its resistance to temozolomide (TMZ) remains intractable. Long non-coding RNAs (lncRNAs) play crucial roles in...
AIMS
Glioblastoma multiforme (GBM) is the deadliest glioma and its resistance to temozolomide (TMZ) remains intractable. Long non-coding RNAs (lncRNAs) play crucial roles in that and this study aimed to investigate underlying mechanism of HOXD-AS2-affected temozolomide sensitivity in glioblastoma.
METHODS
We analyzed and validated the aberrant HOXD-AS2 expression in glioma specimens. Then we explored the function of HOXD-AS2 in vivo and in vitro and a clinical case was also reviewed to examine our findings. We further performed mechanistic experiments to investigate the mechanism of HOXD-AS2 in regulating TMZ sensitivity.
RESULTS
Elevated HOXD-AS2 expression promoted progression and negatively correlated with prognosis of glioma; HOXD-AS2 attenuated temozolomide sensitivity in vitro and in vivo; The clinical case also showed that lower HOXD-AS2 sensitized glioblastoma to temozolomide; STAT3-induced HOXD-AS2 could interact with IGF2BP2 protein to form a complex and sequentially upregulate STAT3 signaling, thus forming a positive feedback loop regulating TMZ sensitivity in glioblastoma.
CONCLUSION
Our study elucidated the crucial role of the HOXD-AS2-STAT3 positive feedback loop in regulating TMZ sensitivity, suggesting that this could be provided as a potential therapeutic candidate of glioblastoma.
Topics: Humans; Temozolomide; Glioblastoma; Feedback; Drug Resistance, Neoplasm; Cell Line, Tumor; Brain Neoplasms; MicroRNAs; Antineoplastic Agents, Alkylating; Gene Expression Regulation, Neoplastic; RNA-Binding Proteins; STAT3 Transcription Factor
PubMed: 37308741
DOI: 10.1111/cns.14277 -
International Journal of Biological... 2023Gliomas are the most aggressive type of malignant brain tumors. Recent studies have demonstrated that the existence of glioma stem cells (GSCs) is critical for glioma...
Gliomas are the most aggressive type of malignant brain tumors. Recent studies have demonstrated that the existence of glioma stem cells (GSCs) is critical for glioma recurrence, metastasis, and chemo- or radio-therapy resistance. Temozolomide (TMZ) has been used as an initial therapy for gliomas. However, the overall survival time is still limiting due to the lack of effective targets and treatment options. Therefore, identifying novel biomarkers for gliomas, especially for GSCs, is important to improve the clinical outcome in the future. In this study, we identify a human-specific long non-coding RNA (lncRNA, ENSG00000250377), termed GSCAR (glioma stem cell associated lncRNA), which is highly expressed in glioma cancerous tissues and cell lines. We reveal that GSCAR positively correlates with tumor grade. Glioma patients with GSCAR high expression exhibit shortened overall survival time, compared to patients with GSCAR low expression. Furthermore, we show that GSCAR knockdown by shRNAs or antisense oligonucleotide (ASO) reduces tumor cell proliferation, migration and xenograft tumor formation abilities. Mechanistic study shows that GSCAR acts as a ceRNA (competing endogenous RNA) for miR-6760-5p to promote the expression of oncogene SRSF1 (serine and arginine rich splicing factor 1). In addition, GSCAR mediates the protein complex formation between DHX9 (DExH-Box helicase 9) and IGF2BP2 (insulin-like growth factor 2 mRNA-binding protein 2), leading to the stabilization of SOX2 (sex-determining region Y-box 2) mRNA and then the transcriptional activation of GSCAR. Depleting GSCAR reduces SOX2 expression and GSC self-renewal ability, but promotes tumor cell responses to TMZ. These findings uncover that GSCAR/miR-6760-5p/SRSF1 axis and GSCAR/DHX9-IGF2BP2/SOX2 positive feedback loop are critical for glioma progression, which could be used as prognostic biomarkers and therapeutic targets in the future.
Topics: Humans; RNA, Long Noncoding; MicroRNAs; Glioma; Temozolomide; Cell Proliferation; Neoplastic Stem Cells; RNA, Messenger; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; RNA-Binding Proteins; SOXB1 Transcription Factors; Serine-Arginine Splicing Factors
PubMed: 37063420
DOI: 10.7150/ijbs.80873 -
Journal of Neuro-oncology Jan 2021Glioblastoma (GBM) has a survival rate of around 2 years with aggressive current standard of care. While other tumors have responded favorably to trials combining... (Review)
Review
INTRODUCTION
Glioblastoma (GBM) has a survival rate of around 2 years with aggressive current standard of care. While other tumors have responded favorably to trials combining immunotherapy and chemotherapy, GBM remains uniformly deadly with minimal increases in overall survival. GBM differ from others due to being isolated behind the blood brain barrier, increased heterogeneity and mutational burden, and immunosuppression from the brain environment and tumor itself.
METHODS
We have reviewed clinical and preclinical studies investigating how different doses (dose intense (DI) and metronomic) and timing of immunotherapy following TMZ treatment can eradicate tumor cells, alter tumor mutational burden, and change immune cells.
RESULTS
Recent clinical trials with standard of care (SoC), DI and metronomic TMZ regimes are no able to completely eradicate GBM. Elevated TMZ levels in DI treatment can overcome MGMT resistance but may result in hypermutation of surviving tumor cells. Higher levels of TMZ will also generate a higher degree of lymphopenia compared to SoC and metronomic regimes in preclinical studies.
CONCLUSION
The different levels of lymphopenia and tumor eradication discussed in this review suggest possible beneficial pairings between immunotherapy and TMZ treatment. Treatments resulting in profound lymphopenia will allow for expansion of vaccine specific T cells or of CAT T cells. Clinical and preclinical studies are currently comparing different combinations of TMZ and immunotherapy timing to treat GBM through a balance between tumor killing and immune cell expansion. More frequent immune monitoring time points in ongoing clinical trials are crucial for further development of these combinations.
Topics: Antineoplastic Agents, Alkylating; Brain Neoplasms; Cell Line, Tumor; Glioblastoma; Humans; Immunotherapy; Lymphopenia; Temozolomide; Treatment Outcome
PubMed: 32813186
DOI: 10.1007/s11060-020-03598-2 -
Cells Aug 2022Glioblastoma (GBM) is the most common and highly lethal type of brain tumor, with poor survival despite advances in understanding its complexity. After current standard... (Review)
Review
Glioblastoma (GBM) is the most common and highly lethal type of brain tumor, with poor survival despite advances in understanding its complexity. After current standard therapeutic treatment, including tumor resection, radiotherapy and concomitant chemotherapy with temozolomide, the median overall survival of patients with this type of tumor is less than 15 months. Thus, there is an urgent need for new insights into GBM molecular characteristics and progress in targeted therapy in order to improve clinical outcomes. The literature data revealed that a number of different signaling pathways are dysregulated in GBM. In this review, we intended to summarize and discuss current literature data and therapeutic modalities focused on targeting dysregulated signaling pathways in GBM. A better understanding of opportunities for targeting signaling pathways that influences malignant behavior of GBM cells might open the way for the development of novel GBM-targeted therapies.
Topics: Brain Neoplasms; Glioblastoma; Humans; Signal Transduction; Temozolomide
PubMed: 36010607
DOI: 10.3390/cells11162530 -
Cancer Biology & Therapy Dec 2024GBM is one of the most malignant tumor in central nervous system. The resistance to temozolomide (TMZ) is inevitable in GBM and the characterization of TMZ resistance...
GBM is one of the most malignant tumor in central nervous system. The resistance to temozolomide (TMZ) is inevitable in GBM and the characterization of TMZ resistance seriously hinders clinical treatment. It is worthwhile exploring the underlying mechanism of aggressive invasion and TMZ resistance in GBM treatment. Bioinformatic analysis was used to analyze the association between RND1 and a series of EMT-related genes. Colony formation assay and cell viability assay were used to assess the growth of U87 and U251 cells. The cell invasion status was evaluated based on transwell and wound-healing assays. Western blot was used to detect the protein expression in GBM cells. Treatment targeted RND1 combined with TMZ therapy was conducted in nude mice to evaluate the potential application of RND1 as a clinical target for GBM. The overexpression of RND1 suppressed the progression and migration of U87 and U251 cells. RND1 knockdown facilitated the growth and invasion of GBM cells. RND1 regulated the EMT of GBM cells via inhibiting the phosphorylation of AKT and GSK3-β. The promoted effects of RND1 on TMZ sensitivity was identified both and . This research demonstrated that the overexpression of RND1 suppressed the migration and EMT status by downregulating AKT/GSK3-β pathway in GBM. RND1 enhanced the TMZ sensitivity of GBM cells both and . Our findings may contribute to the targeted therapy for GBM and the understanding of mechanisms of TMZ resistance in GBM.
Topics: Animals; Mice; Temozolomide; Glioblastoma; Glycogen Synthase Kinase 3; Proto-Oncogene Proteins c-akt; Mice, Nude; Epithelial-Mesenchymal Transition
PubMed: 38444223
DOI: 10.1080/15384047.2024.2321770 -
Neurochemistry International Oct 2021Glioblastoma remains one of the most challenging and devastating cancers, with only a very small proportion of patients achieving 5-year survival. The current standard... (Review)
Review
Glioblastoma remains one of the most challenging and devastating cancers, with only a very small proportion of patients achieving 5-year survival. The current standard of care consists of surgery, followed by radiation therapy with concurrent and maintenance chemotherapy with the alkylating agent temozolomide. To date, this drug is the only one that provides a significant survival benefit, albeit modest, as patients end up acquiring resistance to this drug. As a result, tumor progression and recurrence inevitably occur, leading to death. Several factors have been proposed to explain this resistance, including an upregulated antioxidant system to keep the elevated intracellular ROS levels, a hallmark of cancer cells, under control. In this review, we discuss the mechanisms of chemoresistance -including the important role of glioblastoma stem cells-with emphasis on antioxidant defenses and how agents that impair redox balance (i.e.: sulfasalazine, erastin, CB-839, withaferin, resveratrol, curcumin, chloroquine, and hydroxychloroquine) might be advantageous in combined therapies against this type of cancer.
Topics: Animals; Antineoplastic Agents, Alkylating; Antioxidants; Brain Neoplasms; Drug Resistance, Neoplasm; Glioblastoma; Humans; Neoplastic Stem Cells; Reactive Oxygen Species; Temozolomide
PubMed: 34274381
DOI: 10.1016/j.neuint.2021.105136 -
Current Oncology (Toronto, Ont.) Feb 2023Outcomes for patients with high-grade glioma remain poor. Temozolomide (TMZ) is the only drug approved for first-line treatment of glioblastoma multiforme, the most... (Review)
Review
Outcomes for patients with high-grade glioma remain poor. Temozolomide (TMZ) is the only drug approved for first-line treatment of glioblastoma multiforme, the most aggressive form of glioma. Chronotherapy highlights the potential benefit of timed TMZ administration. This is based on pre-clinical studies of enhanced TMZ-induced glioma cytotoxicity dependent on circadian, oscillating expression of key genes involved in apoptosis, DNA damage repair, and cell-cycle mediated cell death. The current systematic review's primary aim was to evaluate the efficacy and toxicity of TMZ chronotherapy. A systemic review of literature following PRISMA guidelines looking at clinical outcomes on TMZ chronotherapy on gliomas was performed. The search in the English language included three databases (PubMed, EMBASE, and Cochrane) and five conferences from 1946 to April 2022. Two independent reviewers undertook screening, data extraction, and risk-of-bias assessment. A descriptive analysis was conducted due to limited data. Of the 269 articles screened, two unique studies were eligible and underwent abstraction for survival and toxicity findings. Both studies-one a retrospective cohort study (n = 166) and the other a prospective randomized feasibility study (n = 35)-were conducted by the same academic group and suggested a trend for improved overall survival, but possibly increased toxicity when TMZ was administered in the morning (vs. evening). There was limited evidence suggesting possible therapeutic value from administering TMZ in the morning, which may be consistent with the pre-clinical observations of the importance of the timing of TMZ administration in vitro. Larger, pragmatic, prospective randomized controlled trials are needed to ascertain the value of TMZ chronotherapy to provide optimized and equitable care for this population.
Topics: Humans; Temozolomide; Retrospective Studies; Prospective Studies; Brain Neoplasms; Glioma; Chronotherapy; Randomized Controlled Trials as Topic
PubMed: 36826108
DOI: 10.3390/curroncol30020147 -
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