BACKGROUND: Temozolomide (TMZ) resistance is a significant challenge in treating glioblastoma (GBM). Collagen remodeling has been shown to be a critical factor for therapy resistance in other cancers. This study aimed to investigate the mechanism of TMZ chemoresistance by GBM cells reprogramming collagens. METHODS: Key extracellular matrix components, including collagens, were examined in paired primary and recurrent GBM samples as well as in TMZ-treated spontaneous and grafted GBM murine models. Human GBM cell lines (U251, TS667) and mouse primary GBM cells were used for in vitro studies. RNA-sequencing analysis, chromatin immunoprecipitation, immunoprecipitation-mass spectrometry, and co-immunoprecipitation assays were conducted to explore the mechanisms involved in collagen accumulation. A series of in vitro and in vivo experiments were designed to assess the role of the collagen regulators prolyl 4-hydroxylase subunit alpha 1 (P4HA1) and yes-associated protein (YAP) in sensitizing GBM cells to TMZ. RESULTS: This study revealed that TMZ exposure significantly elevated collagen type I (COL I) expression in both GBM patients and murine models. Collagen accumulation sustained GBM cell survival under TMZ-induced stress, contributing to enhanced TMZ resistance. Mechanistically, P4HA1 directly binded to and hydroxylated YAP, preventing ubiquitination-mediated YAP degradation. Stabilized YAP robustly drove collagen type I alpha 1 ( COL1A1) transcription, leading to increased collagen deposition. Disruption of the P4HA1-YAP axis effectively reduced COL I deposition, sensitized GBM cells to TMZ, and significantly improved mouse survival. CONCLUSION P4HA1 maintained YAP-mediated COL1A1 transcription, leading to collagen accumulation and promoting chemoresistance in GBM.
Temozolomide ; Humans ; Glioblastoma/drug therapy* ; Animals ; Mice ; Cell Line, Tumor ; Drug Resistance, Neoplasm/genetics* ; YAP-Signaling Proteins ; Hydroxylation ; Dacarbazine/pharmacology* ; Adaptor Proteins, Signal Transducing/metabolism* ; Transcription Factors/metabolism* ; Collagen/biosynthesis* ; Collagen Type I/metabolism* ; Prolyl Hydroxylases/metabolism* ; Antineoplastic Agents, Alkylating/therapeutic use*

Glioma is the most common lethal tumor of the human brain. The median survival of patients with primary World Health Organization grade IV glioma is only 14.6 months. The World Health Organization classification of tumors of the central nervous system categorized gliomas into lower-grade gliomas and glioblastomas. Unlike primary glioblastoma that usually develop de novo in the elderly, secondary glioblastoma enriched with an isocitrate dehydrogenase mutant typically progresses from lower-grade glioma within 5-10 years from the time of diagnosis. Based on various evolutional trajectories brought on by clonal and subclonal alterations, the evolution patterns of glioma vary according to different theories. Some important features distinguish the normal brain from other tissues, e.g., the composition of the microenvironment around the tumor cells, the presence of the blood-brain barrier, and others. The underlying mechanism of glioma recurrence and evolution patterns of glioma are different from those of other types of cancer. Several studies correlated tumor recurrence with tumor heterogeneity and the immune microenvironment. However, the detailed reasons for the progression and recurrence of glioma remain controversial. In this review, we introduce the different mechanisms involved in glioma progression, including tumor heterogeneity, the tumor microenvironment and drug resistance, and their pre-clinical implements in clinical trials. This review aimed to provide new insights into further clinical strategies for the treatment of patients with recurrent and secondary glioma.
Aged ; Brain Neoplasms/genetics* ; Drug Resistance ; Glioblastoma ; Glioma/genetics* ; Humans ; Mutation ; Neoplasm Recurrence, Local/drug therapy* ; Tumor Microenvironment

BACKGROUND: There has been no practical guidelines for the management of patients with central nervous system (CNS) tumors in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, started to prepare guidelines for CNS tumors from February 2018. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. RESULTS: First, the maximal safe resection if feasible is recommended. After the diagnosis of a glioblastoma with neurosurgical intervention, patients aged ≤70 years with good performance should be treated by concurrent chemoradiotherapy with temozolomide followed by adjuvant temozolomide chemotherapy (Stupp's protocol) or standard brain radiotherapy alone. However, those with poor performance should be treated by hypofractionated brain radiotherapy (preferred)±concurrent or adjuvant temozolomide, temozolomide alone (Level III), or supportive treatment. Alternatively, patients aged >70 years with good performance should be treated by hypofractionated brain radiotherapy+concurrent and adjuvant temozolomide or Stupp's protocol or hypofractionated brain radiotherapy alone, while those with poor performance should be treated by hypofractionated brain radiotherapy alone or temozolomide chemotherapy if the patient has methylated MGMT gene promoter (Level III), or supportive treatment. CONCLUSION: The KSNO's guideline recommends that glioblastomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to the individual comprehensive condition of the patient.
Brain ; Central Nervous System ; Chemoradiotherapy ; Diagnosis ; Drug Therapy ; Glioblastoma ; Humans ; Korea ; Radiotherapy

PURPOSE: Glioblastoma (GBM) carries a high propensity for in-field failure despite trimodality management. Past studies have failed to show outcome improvements with dose-escalation. Herein, we examined trends and outcomes associated with dose-escalation for GBM. MATERIALS AND METHODS: The National Cancer Database was queried for GBM patients who underwent surgical resection and external-beam radiation with chemotherapy. Patients were excluded if doses were less than 59.4 Gy; dose-escalation referred to doses ≥66 Gy. Odds ratios identified predictors of dose-escalation. Univariable and multivariable Cox regressions determined potential predictors of overall survival (OS). Propensity-adjusted multivariable analysis better accounted for indication biases. RESULTS: Of 33,991 patients, 1,223 patients received dose-escalation. Median dose in the escalation group was 70 Gy (range, 66 to 89.4 Gy). The use of dose-escalation decreased from 8% in 2004 to 2% in 2014. Predictors of escalated dose were African American race, lower comorbidity score, treatment at community centers, decreased income, and more remote treatment year. Median OS was 16.2 months and 15.8 months for the standard and dose-escalated cohorts, respectively (p = 0.35). On multivariable analysis, age >60 years, higher comorbidity score, treatment at community centers, decreased education, lower income, government insurance, Caucasian race, male gender, and more remote year of treatment predicted for worse OS. On propensity-adjusted multivariable analysis, age >60 years, distance from center >12 miles, decreased education, government insurance, and male gender predicted for worse outcome. CONCLUSION: Dose-escalated radiotherapy for GBM has decreased over time across the United States, in concordance with guidelines and the available evidence. Similarly, this large study did not discern survival improvements with dose-escalation.
Bias (Epidemiology) ; Cohort Studies ; Comorbidity ; Continental Population Groups ; Drug Therapy ; Education ; European Continental Ancestry Group ; Glioblastoma ; Humans ; Insurance ; Male ; Odds Ratio ; Radiotherapy ; United States

BACKGROUND: There was no practical guideline for the management of patients with central nervous system tumor in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has developed the guideline for glioblastoma. Subsequently, the KSNO guideline for World Health Organization (WHO) grade II cerebral glioma in adults is established. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searching PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords regarding diffuse astrocytoma and oligodendroglioma of brain in adults. RESULTS: Whenever radiological feature suggests lower grade glioma, the maximal safe resection if feasible is recommended globally. After molecular and histological examinations, patients with diffuse astrocytoma, isocitrate dehydrogenase (IDH)-wildtype without molecular feature of glioblastoma should be primarily treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy (Level III) while those with molecular feature of glioblastoma should be treated following the protocol for glioblastomas. In terms of patients with diffuse astrocytoma, IDH-mutant and oligodendroglioma (IDH-mutant and 1p19q codeletion), standard brain radiotherapy and adjuvant PCV (procarbazine+lomustine+vincristine) combination chemotherapy should be considered primarily for the high-risk group while observation with regular follow up should be considered for the low-risk group. CONCLUSION: The KSNO's guideline recommends that WHO grade II gliomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors and clinical characteristics of patients.
Adult ; Astrocytoma ; Brain ; Central Nervous System ; Drug Therapy ; Drug Therapy, Combination ; Follow-Up Studies ; Glioblastoma ; Glioma ; Humans ; Isocitrate Dehydrogenase ; Korea ; Oligodendroglioma ; Radiotherapy ; World Health Organization

BACKGROUND: There was no practical guideline for the management of patients with central nervous system tumor in Korea in the past. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, developed the guideline for glioblastoma successfully and published it in Brain Tumor Research and Treatment, the official journal of KSNO, in April 2019. Recently, the KSNO guideline for World Health Organization (WHO) grade III cerebral glioma in adults has been established. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searches in PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords. Scope of the disease was confined to cerebral anaplastic astrocytoma and oligodendroglioma in adults. RESULTS: Whenever radiological feature suggests high grade glioma, maximal safe resection if feasible is globally recommended. After molecular and histological examinations, patients with anaplastic astrocytoma, isocitrate dehydrogenase (IDH)-mutant should be primary treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy whereas those with anaplastic astrocytoma, NOS, and anaplastic astrocytoma, IDH-wildtype should be treated following the protocol for glioblastomas. In terms of anaplastic oligodendroglioma, IDH-mutant and 1p19q-codeletion, and anaplastic oligodendroglioma, NOS should be primary treated by standard brain radiotherapy and neoadjuvant or adjuvant PCV (procarbazine, lomustine, and vincristine) combination chemotherapy. CONCLUSION: The KSNO's guideline recommends that WHO grade III cerebral glioma of adults should be treated by maximal safe resection if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors.
Adult ; Astrocytoma ; Brain ; Brain Neoplasms ; Central Nervous System ; Drug Therapy ; Drug Therapy, Combination ; Glioblastoma ; Glioma ; Humans ; Isocitrate Dehydrogenase ; Korea ; Lomustine ; Oligodendroglioma ; Radiotherapy ; World Health Organization

Glioblastoma is one of the most common intracranial malignant tumor and its initiation and progression are closely associated with epidermal growth factor receptor (EGFR). EGFR variant III (EGFRvIII) is a mutant EGFR and highly expressed in glioblastoma. EGFRvIII promotes the proliferation and invasiveness of glioblastoma cells and induces drug resistance by signaling networks.
Brain Neoplasms ; Cell Line, Tumor ; ErbB Receptors ; Glioblastoma ; drug therapy ; Humans ; Signal Transduction

Phantosmia is defined as the false perception of odors without any environmental odor stimulus. It is a very rare phenomenon, but it can be caused by a wide variety of conditions, such as viral or allergic rhinosinusitis, head trauma, brain tumor, migraine, temporal lobe epilepsy, stroke, and psychiatric conditions. If it is caused by a brain tumor such as glioblastoma, it can be controlled with steroids or antiepileptic drugs. Phantosmia can also be treated with surgical resection or adjuvant radiotherapy combined with chemotherapy. We report a case of glioblastoma presenting with phantosmia.
Anticonvulsants ; Brain Neoplasms ; Craniocerebral Trauma ; Drug Therapy ; Epilepsy, Temporal Lobe ; Glioblastoma* ; Migraine Disorders ; Odors ; Radiotherapy, Adjuvant ; Steroids ; Stroke

BACKGROUND: While procarbazine, CCNU (lomustine), and vincristine (PCV) has been an alternative chemotherapy option for malignant gliomas, it is worth investigating whether the combination of only procarbazine and CCNU is comparable because vincristine adds toxicity with uncertain benefit. The purpose of this study was to evaluate the feasibility of procarbazine and CCNU chemotherapy for recurrent glioblastoma multiforme (GBM) with O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation. METHODS: Eight patients with recurrent GBM following concurrent chemoradiotherapy and temozolomide (TMZ) adjuvant therapy were enrolled in this trial; they received no other chemotherapeutic agents or target therapy. They received CCNU (75 mg/m²) on day 1 and procarbazine (60 mg/m²) through days 11 and 24 every 4 weeks. The median cycle of CCNU and procarbazine was 3.5 (range: 2–6). RESULTS: One patient achieved stable disease. The median progression-free survival (PFS) with procarbazine and CCNU chemotherapy was eight weeks (range: 5–73), and the PFS rates were 25% and 12.5% at 16 and 30 weeks, respectively. The median overall survival (OS) from the initial diagnosis to death was 40 months, and the median OS from the administration of procarbazine and CCNU chemotherapy to death was 9.7 months (95% confidence interval: 6.7–12.7). Serious adverse events were found at six visits, and two cases were considered to be grade 3 toxicities. CONCLUSION: The efficacy of procarbazine and CCNU chemotherapy is not satisfactory. This study suggests the need to develop other treatment strategies for recurrent and TMZ-refractory GBM. Trial registry at ClinicalTrials.gov, NCT017337346.
Chemoradiotherapy ; Diagnosis ; Disease-Free Survival ; Drug Therapy* ; Glioblastoma* ; Glioma ; Humans ; Lomustine* ; Methylation* ; Procarbazine* ; Vincristine

Glioblastoma is a common brain tumor and the overall survival rate of the patients is very low, so it is an effective way to develop the potential chemotherapy or adjuvant chemotherapy drugs in glioblastoma treatment. As a well-known antimalarial drug, artesunate(ARTs) has clear side effects, and recently it has been reported to have antitumor effects, but rarely reported in glioblastoma. Different concentrations of ARTs were used to treat the glioblastoma cells, and then the inhibitory effect of ARTs on glioblastoma proliferation was detected by MTT assay; Ki67 immunofluorescence assay was used to detect the proliferation of cells; Soft agar experiment was used to explain the clonal formation abilities ; Flow Cytometry was used to detect the cell cycle; and Western blot assay was used to determine the expression of key cell cycle protein. MTT assay results indicated that ARTs-treated glioblastoma cell A172, U251, U87 were significantly inhibited in a time-and-dose dependent manner as compared to the control group(DMSO treatment group). Soft agar experiment showed that ARTs could significantly reduce the clonal formation ability of glioblastoma. Furthermore, Flow cytometry analysis showed that ARTs could obviously increase the cell proportion in G₀/G₁ phase and reduce the cell proportion in S phase. Western blot results showed that the expressions of cell cycle-related proteins CDK2, CDK4, cyclin D1 and cyclin B1 were all obviously down-regulated. Above all, ARTs may inhibit the proliferation of glioblastoma cells by arresting cell cycle in G₀/G₁ phase through down-regulating the expression of CDK2, CDK4, cyclin D1, cyclin B1. These results may not only provide a novel method for rediscovering and reusing ARTs but also provide a new potential drug for treating glioblastoma.
Antineoplastic Agents ; pharmacology ; Apoptosis ; Artesunate ; pharmacology ; Cell Cycle Checkpoints ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclin B1 ; metabolism ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 2 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Glioblastoma ; drug therapy ; pathology ; Humans