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Redox Biology Jul 2024Temozolomide (TMZ) is a widely utilized chemotherapy treatment for patients with glioblastoma (GBM), although drug resistance constitutes a major therapeutic hurdle....
Temozolomide (TMZ) is a widely utilized chemotherapy treatment for patients with glioblastoma (GBM), although drug resistance constitutes a major therapeutic hurdle. Emerging evidence suggests that ferroptosis-mediated therapy could offer an appropriate alternative treatment option against cancer cells that are resistant to certain drugs. However, recurrent gliomas display robust ferroptosis resistance, although the precise mechanism of resistance remains elusive. In the present work, we report that proline rich protein 11 (PRR11) depletion significantly sensitizes GBM cells to TMZ by inducing ferroptosis. Mechanistically, PRR11 directly binds to and stabilizes dihydroorotate dehydrogenase (DHODH), which leads to glioma ferroptosis-resistant in a DHODH-dependent manner in vivo and in vitro. Furthermore, PRR11 inhibits HERC4 and DHODH binding, by suppressing the recruitment of E3 ubiquitin ligase HERC4 and polyubiquitination degradation of DHODH at the K306 site, which maintains DHODH protein stability. Importantly, downregulated PRR11 increases lipid peroxidation and alters DHODH-mediated mitochondrial morphology, thereby promoting ferroptosis and increasing TMZ chemotherapy sensitivity. In conclusion, our results reveal a mechanism via which PRR11 drives ferroptosis resistance and identifies ferroptosis induction and TMZ as an attractive combined therapeutic strategy for GBM.
Topics: Humans; Ferroptosis; Glioblastoma; Temozolomide; Drug Resistance, Neoplasm; Cell Line, Tumor; Mice; Dihydroorotate Dehydrogenase; Animals; Gene Expression Regulation, Neoplastic; Brain Neoplasms
PubMed: 38838551
DOI: 10.1016/j.redox.2024.103220 -
Cancer Research Communications Jun 2024Glioblastoma (GBM) is the deadliest adult brain cancer. Under the current standard of care, almost all patients succumb to the disease and novel treatments are urgently...
UNLABELLED
Glioblastoma (GBM) is the deadliest adult brain cancer. Under the current standard of care, almost all patients succumb to the disease and novel treatments are urgently needed. Recognizing that GBMs are addicted to cholesterol, past clinical trials have repurposed statins against GBM but failed. The purpose of this study was to test whether treatments that upregulate the cholesterol biosynthesis pathway in GBM would generate a metabolic vulnerability that can be exploited using statins and to determine the underlying mechanisms.Effects of radiotherapy and temozolomide or dopamine receptor antagonists on the mevalonate pathway in GBM were assessed in vitro and in vivo. The impact of statins on self-renewal of glioma stem cells and median survival was studied. Branches of the mevalonate pathway were probed to identify relevant effector proteins.Cells surviving combination treatments that converge in activating the immediate early response, universally upregulated the mevalonate pathway and increased stemness of GBM cells through activation of the Rho-GTPase Rac-1. Activation of the mevalonate pathway and Rac-1 was inhibited by statins, which led to improved survival in mouse models of glioblastoma when combined with radiation and drugs that target the glioma stem cell pool and plasticity of glioma cells.We conclude that a combination of dopamine receptor antagonists and statins could potentially improve radiotherapy outcome and warrants further investigation.
SIGNIFICANCE
Combination therapies that activate the mevalonate pathway in GBM cells after sublethal treatment enhance self-renewal and migratory capacity through Rac-1 activation, which creates a metabolic vulnerability that can be further potentially exploited using statins.
Topics: Glioblastoma; Mevalonic Acid; Humans; Animals; rac1 GTP-Binding Protein; Mice; Brain Neoplasms; Cell Line, Tumor; Temozolomide; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Neoplasm Recurrence, Local; Xenograft Model Antitumor Assays; Neoplastic Stem Cells; Signal Transduction; Dopamine Antagonists
PubMed: 38837899
DOI: 10.1158/2767-9764.CRC-24-0049 -
Oncology Research 2024The dysregulation of Isocitrate dehydrogenase (IDH) and the subsequent production of 2-Hydroxyglutrate (2HG) may alter the expression of epigenetic proteins in Grade 4...
The interplay mechanism between IDH mutation, MGMT-promoter methylation, and PRMT5 activity in the progression of grade 4 astrocytoma: unraveling the complex triad theory.
BACKGROUND
The dysregulation of Isocitrate dehydrogenase (IDH) and the subsequent production of 2-Hydroxyglutrate (2HG) may alter the expression of epigenetic proteins in Grade 4 astrocytoma. The interplay mechanism between IDH, O-6-methylguanine-DNA methyltransferase (-promoter methylation, and protein methyltransferase proteins-5 ( activity, with tumor progression has never been described.
METHODS
A retrospective cohort of 34 patients with G4 astrocytoma is classified into IDH-mutant and IDH-wildtype tumors. Both groups were tested for -promoter methylation and through methylation-specific and gene expression PCR analysis. Inter-cohort statistical significance was evaluated.
RESULTS
Both IDH-mutant WHO grade 4 astrocytomas (n = 22, 64.7%) and IDH-wildtype glioblastomas (n = 12, 35.3%) had upregulated gene expression except in one case. Out of the 22 IDH-mutant tumors, 10 (45.5%) tumors showed -promoter methylation and 12 (54.5%) tumors had unmethylated . All IDH-wildtype tumors had unmethylated . There was a statistically significant relationship between -promoter methylation and IDH in G4 astrocytoma (-value = 0.006). Statistically significant differences in progression-free survival (PFS) were also observed among all G4 astrocytomas that expressed and received either temozolomide (TMZ) or TMZ plus other chemotherapies, regardless of their IDH or -methylation status (-value=0.0014). Specifically, IDH-mutant tumors that had upregulated activity and -promoter methylation, who received only TMZ, have exhibited longer PFS.
CONCLUSIONS
The relationship between , -promoter, and IDH is not tri-directional. However, accumulation of D2-hydroxyglutarate (2-HG), which partially activates 2-OG-dependent deoxygenase, may not affect their activities. In IDH-wildtype glioblastomas, the 2HG-2OG pathway is typically inactive, leading to upregulation. TMZ alone, compared to TMZ-plus, can increase PFS in upregulated tumors. Thus, using a inhibitor in G4 astrocytomas may help in tumor regression.
Topics: Humans; Protein-Arginine N-Methyltransferases; Tumor Suppressor Proteins; Promoter Regions, Genetic; DNA Repair Enzymes; DNA Modification Methylases; DNA Methylation; Isocitrate Dehydrogenase; Male; Female; Astrocytoma; Disease Progression; Middle Aged; Mutation; Adult; Retrospective Studies; Brain Neoplasms; Neoplasm Grading; Aged; Temozolomide; Gene Expression Regulation, Neoplastic
PubMed: 38827324
DOI: 10.32604/or.2024.051112 -
Scientific Reports May 2024Radiotherapy is the standard treatment for glioblastoma (GBM), but the overall survival rate for radiotherapy treated GBM patients is poor. The use of adjuvant and...
Radiotherapy is the standard treatment for glioblastoma (GBM), but the overall survival rate for radiotherapy treated GBM patients is poor. The use of adjuvant and concomitant temozolomide (TMZ) improves the outcome; however, the effectiveness of this treatment varies according to MGMT levels. Herein, we evaluated whether MGMT expression affected the radioresponse of human GBM, GBM stem-like cells (GSCs), and melanoma. Our results indicated a correlation between MGMT promoter methylation status and MGMT expression. MGMT-producing cell lines ACPK1, GBMJ1, A375, and MM415 displayed enhanced radiosensitivity when MGMT was silenced using siRNA or when inhibited by lomeguatrib, whereas the OSU61, NSC11, WM852, and WM266-4 cell lines, which do not normally produce MGMT, displayed reduced radiosensitivity when MGMT was overexpressed. Mechanistically lomeguatrib prolonged radiation-induced γH2AX retention in MGMT-producing cells without specific cell cycle changes, suggesting that lomeguatrib-induced radiosensitization in these cells is due to radiation-induced DNA double-stranded break (DSB) repair inhibition. The DNA-DSB repair inhibition resulted in cell death via mitotic catastrophe in MGMT-producing cells. Overall, our results demonstrate that MGMT expression regulates radioresponse in GBM, GSC, and melanoma, implying a role for MGMT as a target for radiosensitization.
Topics: Humans; Glioblastoma; Tumor Suppressor Proteins; DNA Repair Enzymes; Melanoma; DNA Modification Methylases; Cell Line, Tumor; Radiation Tolerance; Neoplastic Stem Cells; Promoter Regions, Genetic; DNA Methylation; DNA Repair; DNA Breaks, Double-Stranded; Gene Expression Regulation, Neoplastic; Temozolomide; Brain Neoplasms; Purines
PubMed: 38811596
DOI: 10.1038/s41598-024-61240-x -
Acta Cirurgica Brasileira 2024To evaluate the chemotherapeutic activity of temozolomide counter to mammary carcinoma.
PURPOSE
To evaluate the chemotherapeutic activity of temozolomide counter to mammary carcinoma.
METHODS
In-vitro anticancer activity has been conducted on MCF7 cells, and mammary carcinoma has been induced in Wistar rats by introduction of 7, 12-Dimethylbenz(a)anthracene (DMBA), which was sustained for 24 weeks. Histopathology, immunohistochemistry, cell proliferation study and apoptosis assay via TUNEL method was conducted to evaluate an antineoplastic activity of temozolomide in rat breast tissue.
RESULTS
IC50 value of temozolomide in MCF7 cell has been obtained as 103 μM, which demonstrated an initiation of apoptosis. The temozolomide treatment facilitated cell cycle arrest in G2/M and S phase dose dependently. The treatment with temozolomide suggested decrease of the hyperplastic abrasions and renovation of the typical histological features of mammary tissue. Moreover, temozolomide therapy caused the downregulation of epidermal growth factor receptor, extracellular signal-regulated kinase, and metalloproteinase-1 expression and upstream of p53 and caspase-3 proliferation to indicate an initiation of apoptotic events.
CONCLUSIONS
The occurrence of mammary carcinoma has been significantly decreased by activation of apoptotic pathway and abrogation of cellular propagation that allowable for developing a suitable mechanistic pathway of temozolomide in order to facilitate chemotherapeutic approach.
Topics: Temozolomide; Animals; Apoptosis; Female; ErbB Receptors; Rats, Wistar; Antineoplastic Agents, Alkylating; Matrix Metalloproteinase 1; Cell Proliferation; Dacarbazine; Breast Neoplasms; Humans; MCF-7 Cells; Extracellular Signal-Regulated MAP Kinases; Immunohistochemistry; Reproducibility of Results; Rats; Mammary Neoplasms, Experimental
PubMed: 38808816
DOI: 10.1590/acb391624 -
Targeting ARNT attenuates chemoresistance through destabilizing p38α-MAPK signaling in glioblastoma.Cell Death & Disease May 2024Glioblastoma (GBM) is the most aggressive and lethal brain tumor in adults. This study aimed to investigate the functional significance of aryl hydrocarbon receptor...
Glioblastoma (GBM) is the most aggressive and lethal brain tumor in adults. This study aimed to investigate the functional significance of aryl hydrocarbon receptor nuclear translocator (ARNT) in the pathogenesis of GBM. Analysis of public datasets revealed ARNT is upregulated in GBM tissues compared to lower grade gliomas or normal brain tissues. Higher ARNT expression correlated with the mesenchymal subtype and poorer survival in GBM patients. Silencing ARNT using lentiviral shRNAs attenuated the proliferative, invasive, and stem-like capabilities of GBM cell lines, while ARNT overexpression enhanced these malignant phenotypes. Single-cell RNA sequencing uncovered that ARNT is highly expressed in a stem-like subpopulation and is involved in regulating glycolysis, hypoxia response, and stress pathways. Mechanistic studies found ARNT activates p38 mitogen-activated protein kinase (MAPK) signaling to promote chemoresistance in GBM cells. Disrupting the ARNT/p38α protein interaction via the ARNT PAS-A domain restored temozolomide sensitivity. Overall, this study demonstrates ARNT functions as an oncogenic driver in GBM pathogenesis and represents a promising therapeutic target.
Topics: Humans; Glioblastoma; Aryl Hydrocarbon Receptor Nuclear Translocator; Drug Resistance, Neoplasm; Cell Line, Tumor; Brain Neoplasms; MAP Kinase Signaling System; Animals; Cell Proliferation; Mitogen-Activated Protein Kinase 14; Mice; Gene Expression Regulation, Neoplastic; Temozolomide; Mice, Nude; Signal Transduction
PubMed: 38806469
DOI: 10.1038/s41419-024-06735-1 -
PloS One 2024Pheochromocytoma, or paraganglioma (PPGL), is a tumor that arises from catecholamine-producing chromaffin cells of the adrenal medulla or paraganglion. Systemic therapy,...
Evaluation of pharmacokinetics, safety, and efficacy of [211At] meta-astatobenzylguanidine ([211At] MABG) in patients with pheochromocytoma or paraganglioma (PPGL): A study protocol.
BACKGROUND
Pheochromocytoma, or paraganglioma (PPGL), is a tumor that arises from catecholamine-producing chromaffin cells of the adrenal medulla or paraganglion. Systemic therapy, such as the combination of cyclophosphamide, vincristine, and dacarbazine or therapeutic radiopharmaceuticals such as [131I] meta-iodobenzylguanidine (MIBG), may be administered in cases of locally advanced tumors or distant metastases. However, the current therapies are limited in terms of efficacy and implementation. [211At] meta-astatobenzylguanidine (MABG) is an alpha-emitting radionuclide-labeled ligand that has demonstrated remarkable tumor-reducing effects in preclinical studies, and is expected to have a high therapeutic effect on pheochromocytoma cells.
METHODS
We are currently conducting an investigator-initiated first-in-human clinical trial to evaluate the pharmacokinetics, safety, and efficacy of [211At] MABG. Patients with locally unresectable or metastatic PPGL refractory to standard therapy and scintigraphically positive [123I] MIBG aggregation are being recruited, and a 3 + 3 dose escalation design was adopted. The initial dose of [211At] MABG is 0.65 MBq/kg, with a dose escalation in a 1:2:4 ratio in each cohort. Dose-limiting toxicity is observed for 6 weeks after a single bolus dose of [211At] MABG, and the patients are observed for 3 months to explore safety and efficacy profiles. The primary endpoint is dose-limiting toxicity to determine both maximum tolerated and recommended doses. The secondary endpoints include radiopharmacokinetics, urinary radioactive excretion rate, urinary catecholamine response rate, objective response rate, progression free survival, [123I] MIBG scintigraphy on reducing tumor accumulation, and quality of life.
TRIALS REGISTRATION
jRCT2021220012 registered on 17 June 2022.
Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Adrenal Gland Neoplasms; Guanidines; Paraganglioma; Pheochromocytoma; Radiopharmaceuticals; Treatment Outcome; Clinical Trials, Phase I as Topic
PubMed: 38805424
DOI: 10.1371/journal.pone.0303623 -
Photodiagnosis and Photodynamic Therapy Feb 2024For malignant glioma, intraoperative photodynamic therapy (PDT) using talaporfin sodium is a powerful tool for local tumor control, when gross total removal is...
BACKGROUND
For malignant glioma, intraoperative photodynamic therapy (PDT) using talaporfin sodium is a powerful tool for local tumor control, when gross total removal is performed. However, the efficacy of PDT for non-totally resectable malignant glioma has not been clearly confirmed. Therefore, the purpose of this study was to clarify the usefulness of PDT using talaporfin sodium for non-totally resectable malignant glioma.
METHODS
Eighteen patients with malignant glioma (16 new onset, 2 recurrent) in whom gross total removal was judged to be difficult from the images obtained before surgery were evaluated. Fifteen patients had glioblastoma (14 newly diagnosed, 1 recurrent), and 3 patients had anaplastic oligodendroglioma (2 newly diagnosed, 1 recurrent). The whole resection cavity was subjected to PDT during the surgery. For newly diagnosed glioblastoma, postoperative therapy involved the combined use of radiation and temozolomide. Bevacizumab treatment was also started at an early stage after surgery.
RESULTS
In some patients, reduction of the residual tumor was observed at an early stage of chemoradiotherapy after the surgery, suggesting the positive effect of PDT. Recurrence occurred in 15 of the 18 patients during the course of treatment. Distant recurrence occurred in 8 of these 15 patients, despite good local tumor control. In the 14 patients with newly diagnosed glioblastoma, the median progression-free survival was almost 10.5 months, and the median overall survival was almost 16.9 months.
CONCLUSIONS
PDT for malignant glioma is expected to slightly improve local tumor control for non-totally resectable lesions.
Topics: Humans; Photochemotherapy; Male; Female; Photosensitizing Agents; Porphyrins; Middle Aged; Glioma; Aged; Adult; Brain Neoplasms; Neoplasm Recurrence, Local; Temozolomide
PubMed: 38787766
DOI: 10.1016/j.pdpdt.2023.103869 -
Journal of Cancer Research and Clinical... May 2024Previous research has shown that both temozolomide (TMZ) and PD-1/L1 inhibitors (PD-1/L1) alone exhibit certain potential in the treatment of non-small cell lung cancer...
OBJECTIVE
Previous research has shown that both temozolomide (TMZ) and PD-1/L1 inhibitors (PD-1/L1) alone exhibit certain potential in the treatment of non-small cell lung cancer (NSCLC) with brain metastases (BM), in this study, we will explore combining the two in order to seek new effective treatment options for NSCLC with BM.
MATERIAL AND METHODS
During 2021.1 to 2023.12, we collected the date of these pretreated-NSCLC with BM who accept the treatment of TMZ and PD-1/L1, the objective response ratio (ORR), progression-free survival (PFS) and overall survival (OS) were set as the primary endpoint, meanwhile, the toxicity of such regimen was also recorded.
RESULTS
About 42 patients are enrolled, our primary analysis demonstrated that the ORR of such regimen toward NSCLC with BM was 26.19%, with Approximate intracranial and extracranial lesion ORR was 6% and 20% respectively, the DCR was about 64.29%, the mean PFS and OS was about 4 m and 8.5 m. Further analysis indicated that the efficiency correlated with the diagnosis-Specific Graded Prognostic Assessment (ds-GPA) score. Moreover, the toxicity can also be tolerated, indicating the application potential of such regimen against NSCLC with BM.
CONCLUSIONS
Our results exhibited that with tolerated toxicity, the combination of TMZ and PD-1/L1 shows promising efficiency against NSCLC with BM, this would be of great significance for the treatment of NSCLC with brain metastasis. However, due to the limitation of sample and retrospective property, the real value of such regimen needed to be further confirmed in the future.
Topics: Humans; Temozolomide; Carcinoma, Non-Small-Cell Lung; Brain Neoplasms; Lung Neoplasms; Retrospective Studies; Male; Middle Aged; Female; Aged; Immune Checkpoint Inhibitors; Adult; Antineoplastic Combined Chemotherapy Protocols; Programmed Cell Death 1 Receptor; B7-H1 Antigen
PubMed: 38780840
DOI: 10.1007/s00432-024-05808-0 -
Theranostics 2024The large-scale genomic analysis classifies glioblastoma (GBM) into three major subtypes, including classical (CL), proneural (PN), and mesenchymal (MES) subtypes. Each...
The large-scale genomic analysis classifies glioblastoma (GBM) into three major subtypes, including classical (CL), proneural (PN), and mesenchymal (MES) subtypes. Each of these subtypes exhibits a varying degree of sensitivity to the temozolomide (TMZ) treatment, while the prognosis corresponds to the molecular and genetic characteristics of the tumor cell type. Tumors with MES features are predominantly characterized by the NF1 deletion/alteration, leading to sustained activation of the RAS and PI3K-AKT signaling pathways in GBM and tend to acquire drug resistance, resulting in the worst prognosis compared to other subtypes (PN and CL). Here, we used the CRISPR/Cas9 library screening technique to detect TMZ-related gene targets that might play roles in acquiring drug resistance, using overexpressed KRAS-G12C mutant GBM cell lines. The study identified a key therapeutic strategy to address the chemoresistance against the MES subtype of GBM. The CRISPR-Cas9 library screening was used to discover genes associated with TMZ resistance in the U87-KRAS (U87-MG which is overexpressed KRAS-G12C mutant) cells. The patient-derived GBM primary cell line TBD0220 was used for experimental validations in vivo and in vitro. Chromatin isolation by RNA purification (ChIRP) and chromatin immunoprecipitation (ChIP) assays were used to elucidate the silencing mechanism of tumor suppressor genes in the MES-GBM subtype. The small-molecule inhibitor EPIC-0412 was obtained through high-throughput screening. Transmission electron microscopy (TEM) was used to characterize the exosomes (Exos) secreted by GBM cells after TMZ treatment. Blood-derived Exos-based targeted delivery of siRNA, TMZ, and EPIC-0412 was optimized to tailor personalized therapy in vivo. Using the genome-wide CRISPR-Cas9 library screening, we found that the ERBIN gene could be epigenetically regulated in the U87-KRAS cells. ERBIN overexpression inhibited the RAS signaling and downstream proliferation and invasion effects of GBM tumor cells. EPIC-0412 treatment inhibited tumor proliferation and EMT progression by upregulating the ERBIN expression both in vitro and in vivo. Genome-wide CRISPR-Cas9 screening also identified RASGRP1(Ras guanine nucleotide-releasing protein 1) and VPS28(Vacuolar protein sorting-associated protein 28) genes as synthetically lethal in response to TMZ treatment in the U87-KRAS cells. We found that RASGRP1 activated the RAS-mediated DDR pathway by promoting the RAS-GTP transformation. VPS28 promoted the Exos secretion and decreased intracellular TMZ concentration in GBM cells. The targeted Exos delivery system encapsulating drugs and siRNAs together showed a powerful therapeutic effect against GBM in vivo. We demonstrate a new mechanism by which ERBIN is epigenetically silenced by the RAS signaling in the MES subtype of GBM. Restoration of the ERBIN expression with EPIC-0412 significantly inhibits the RAS signaling downstream. RASGRP1 and VPS28 genes are associated with the promotion of TMZ resistance through RAS-GDP to RAS-GTP transformation and TMZ efflux, as well. A quadruple combination therapy based on a targeted Exos delivery system demonstrated significantly reduced tumor burden in vivo. Therefore, our study provides new insights and therapeutic approaches for regulating tumor progression and TMZ resistance in the MES-GBM subtype.
Topics: Glioblastoma; Temozolomide; Humans; Drug Resistance, Neoplasm; CRISPR-Cas Systems; Cell Line, Tumor; Animals; Exosomes; Mice; Brain Neoplasms; Carcinogenesis; Mice, Nude; Xenograft Model Antitumor Assays
PubMed: 38773970
DOI: 10.7150/thno.92703