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Science Advances Jun 2024Poor prognosis and drug resistance in glioblastoma (GBM) can result from cellular heterogeneity and treatment-induced shifts in phenotypic states of tumor cells,...
Poor prognosis and drug resistance in glioblastoma (GBM) can result from cellular heterogeneity and treatment-induced shifts in phenotypic states of tumor cells, including dedifferentiation into glioma stem-like cells (GSCs). This rare tumorigenic cell subpopulation resists temozolomide, undergoes proneural-to-mesenchymal transition (PMT) to evade therapy, and drives recurrence. Through inference of transcriptional regulatory networks (TRNs) of patient-derived GSCs (PD-GSCs) at single-cell resolution, we demonstrate how the topology of transcription factor interaction networks drives distinct trajectories of cell-state transitions in PD-GSCs resistant or susceptible to cytotoxic drug treatment. By experimentally testing predictions based on TRN simulations, we show that drug treatment drives surviving PD-GSCs along a trajectory of intermediate states, exposing vulnerability to potentiated killing by siRNA or a second drug targeting treatment-induced transcriptional programs governing nongenetic cell plasticity. Our findings demonstrate an approach to uncover TRN topology and use it to rationally predict combinatorial treatments that disrupt acquired resistance in GBM.
Topics: Humans; Neoplastic Stem Cells; Gene Regulatory Networks; Drug Resistance, Neoplasm; Glioma; Gene Expression Regulation, Neoplastic; Temozolomide; Brain Neoplasms; Cell Line, Tumor; Glioblastoma
PubMed: 38848360
DOI: 10.1126/sciadv.adj7706 -
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 -
Cellular and Molecular Biology... Jun 2024This study aimed to explore the regulatory effects and associated mechanisms of adiponectin on apoptosis and proliferation in the LN18 glioma cell line through the AMPK...
This study aimed to explore the regulatory effects and associated mechanisms of adiponectin on apoptosis and proliferation in the LN18 glioma cell line through the AMPK and Akt signaling pathways. Additionally, we sought to elucidate the impact of adiponectin on the chemosensitivity of the LN18 glioma cell line to temozolomide (TMZ). The proliferation rate of glioma cells treated with adiponectin was assessed using the cholecystokinin (CCK8) assay. The Western blot analysis was employed to assess the expression of p-Akt, p-AMPK, p-mTOR, cleaved caspase3, Bax, Cyclin D1, and Cyclin B1 following adiponectin treatment. Cell apoptosis was quantified using AnnexinV/PI flow cytometry, while changes in the cell cycle were detected using PI staining flow cytometry. The findings revealed that adiponectin upregulates p-AMPK expression and downregulates p-mTOR expression in the PTEN wild-type glioma cell line LN18, with no discernible effect on p-Akt expression. Moreover, adiponectin inhibits the proliferation rate of the PTEN wild-type glioma cell line LN18, enhances the expression of cleaved caspase3 and Bax, and significantly elevates the apoptosis rate, as evidenced by AnnexinV/PI flow cytometry. Adiponectin was observed to suppress the expression of Cyclin D1 and Cyclin B1, increase the number of cells in the G1 phase, and promote autophagy. Additionally, adiponectin augments the expression of Beclin1 and the ratio of LC3II/I in the PTEN wild-type glioma cell line LN18, while decreasing p62 expression. In conclusion, this study posits that adiponectin holds therapeutic promise for glioma treatment. Furthermore, adiponectin enhances the inhibitory effect of TMZ on the proliferation rate of LN18 cells when treated with 0.1 mM and 1 mM TMZ. These results collectively suggest that adiponectin impedes proliferation, encourages apoptosis and autophagy in the LN18 glioma cell line, and heightens its sensitivity to the chemotherapeutic drug TMZ.
Topics: Adiponectin; Apoptosis; Humans; Glioma; Autophagy; Cell Proliferation; Cell Line, Tumor; Temozolomide; Proto-Oncogene Proteins c-akt; TOR Serine-Threonine Kinases; Signal Transduction; AMP-Activated Protein Kinases
PubMed: 38836664
DOI: 10.14715/cmb/2024.70.6.27 -
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 -
Current Radiopharmaceuticals 2024Exposure to physical contamination during chemotherapy, including non-ionizing electromagnetic fields, raises concerns about the widespread sources of exposure to this...
BACKGROUND
Exposure to physical contamination during chemotherapy, including non-ionizing electromagnetic fields, raises concerns about the widespread sources of exposure to this type of radiation. Glioblastoma multiforme (GBM) is an aggressive central nervous system tumor that is hard to treat due to resistance to drugs such as temozolomide (TMZ).
OBJECTIVE
Electromagnetic fields (EMF) and haloperidol (HLP) may have anticancer effects. In this study, we investigated the effects of TMZ, HLP, and EMF on GBM cell lines and analyzed the association between non-ionizing radiation and the risk of change in drug performance.
METHODS
Cell viability and reactive oxygen species (ROS) generation were measured by MTT and NBT assay, respectively. Then, the expression levels of breast cancer-resistant protein (BCRP), Bax, Bcl2, Nestin, vascular endothelial growth factor (VEGF) genes, and P53, Bax, and Bcl2 Proteins were evaluated by real-time PCR and western blot.
RESULTS
Co-treatment of GBM cells by HLP and TMZ enhanced apoptosis in T-98G and A172 cells by increasing the expression of P53 and Bax and decreasing Bcl-2. Interestingly, exposure of GBM cells to EMF decreased apoptosis in the TMZ+HLP group.
CONCLUSION
In conclusion, EMF reduced the synergistic effect of TMZ and HLP. This hypothesis that patients who are treated for brain tumors and suffer from depression should not be exposed to EMF is proposed in the present study. There appears to be an urgent need to reconsider exposure limits for low-frequency magnetic fields, based on experimental and epidemiological research, the relationship between exposure to non-ionizing radiation and adverse human health effects.
Topics: Humans; Apoptosis; Nestin; Temozolomide; Haloperidol; Vascular Endothelial Growth Factor A; ATP Binding Cassette Transporter, Subfamily G, Member 2; Cell Line, Tumor; Electromagnetic Fields; Cell Survival; Neoplasm Proteins; Glioblastoma; Reactive Oxygen Species; Brain Neoplasms; Antineoplastic Agents, Alkylating; Glioma
PubMed: 38817005
DOI: 10.2174/0118744710258350230921065159 -
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