Glioma-derived cancer stem cells are hypersensitive to proteasomal inhibition.

Although proteasome inhibitors (PIs) are used as anticancer drugs to treat various cancers, their relative therapeutic efficacy on stem cells vs. bulk cancers remains unknown. Here, we show that stem cells derived from gliomas, GSCs, are up to 1,000-fold more sensitive to PIs (IC50, 27-70 nM) compared with their differentiated controls (IC50, 47 to ¼100 µM). The stemness of GSCs correlates to increased ubiquitination, whose misregulation readily triggers apoptosis. PI-induced apoptosis of GSCs is independent of NF-κB but involves the phosphorylation of c-Jun N-terminal kinase as well as the transcriptional activation of endoplasmic reticulum (ER) stress-associated proapoptotic mediators. In contrast to the general notion that ER stress-associated apoptosis is signaled by prolonged unfolded protein response (UPR), GSC-selective apoptosis is instead counteracted by the UPR ATF3 is a key mediator in GSC-selective apoptosis. Pharmaceutical uncoupling of the UPR from its downstream apoptosis sensitizes GSCs to PIs in vitro and during tumorigenesis in mice. Thus, a combinational treatment of a PI with an inhibitor of UPR-coupled apoptosis may enhance targeting of stem cells in gliomas.

Restoration of miR-29b exerts anti-cancer effects on glioblastoma.

BACKGROUND: Glioblastoma multiforme (GBM) is known as one of the most fatal forms of cancer. MicroRNAs have been widely implicated in the regulation of mammalian development and pathogenesis. The brain-enriched miR-29 subfamilies are known to be exclusively expressed in the developing brain, and they are aberrantly down-regulated in GBM. This study aims to elucidate the role of miR-29b in GBM development and the feasibility of therapeutic targeting using conjugated nanoparticles. METHODS: After confirmation of miR-29b expression levels in GBM tissues by analysis of open source data, the anticancer effect of miR-29b was tested by the introduction of syn-hsa-miR-29b-3p in the A172 GBM cell line. In vitro studies of cell viability and apoptosis and ex vivo study using GBM tissue slice cultures from 3 patients and nanoparticle delivery of miR-29b were performed. RESULTS: We discovered an increase in apoptotic cell populations with the introduction of miR-29b in the GBM cell line. An established human-derived GBM tissue slice culture system confirmed the anticancer effect of miR-29b-conjugated nanoparticles. Using PCR array, we found that exogenous miR-29b inhibits the expression of COL1A2, COL3A1, COL4A1, ELN, ITGA11, MMP24, and SPARC, which mediates an anticancer effect. CONCLUSIONS: miR-29b may serve as a putative therapeutic molecule when its expression is restored using a nanoparticle delivery system in GBM.

Factors Associated with Clinical Outcomes in Patients with Primary Intraventricular Hemorrhage.

BACKGROUND Primary intraventricular hemorrhage (PIVH) is an uncommon type of intracerebral hemorrhage. Owing to its rarity, the clinical and radiological factors affecting outcomes in patients with PIVH have not been widely studied. MATERIAL AND METHODS We retrospectively reviewed 112 patients (mean age 53 years) treated for PIVH at our institution from January 2004 to December 2014. Clinical and radiological parameters were analyzed 3 months after initial presentation to identify factors associated with clinical outcomes, as assessed by the Glasgow Outcome Scale (favorable ≥4, unfavorable <4). RESULTS Of the 99 patients who underwent angiography, causative vascular abnormalities were found in 46%, and included Moyamoya disease, arteriovenous malformation, and cerebral aneurysm. At 3 months after initial presentation, 64% and 36% of patients were in the favorable and unfavorable outcome groups, respectively. The mortality rate was 19%. However, most survivors had no or mild deficits. Age, initial Glasgow Coma Scale (GCS) score, simplified acute physiology score (SAPS II), modified Graeb score, and various radiological parameters reflecting ventricular dilatation were significantly different between the groups. Specifically, a GCS score of less than 13 (p=0.015), a SAPS II score of less than 33 (p=0.039), and a dilated fourth ventricle (p=0.043) were demonstrated to be independent predictors of an unfavorable clinical outcome. CONCLUSIONS In this study we reveal independent predictors of poor outcome in primary intraventricular hemorrhage patients, and show that nearly half of the patients in our study had predisposing vascular abnormalities. Routine angiography is recommended in the evaluation of PIVH to identify potentially treatable etiologies, which may enhance long-term prognosis.

Reactive oxygen species production has a critical role in hypoxia-induced Stat3 activation and angiogenesis in human glioblastoma.

Glioblastoma is the most aggressive primary brain tumor with hypoxia-associated morphologic features including pseudopalisading necrosis and endothelial hyperplasia. It has been known that hypoxia can activate signal transducer and activator of transcription 3 (Stat3) and subsequently induce angiogenesis. However, the molecular mechanism underlying hypoxia-induced Stat3 activation has not been defined. In this study, we explored the possible implication of reactive oxygen species (ROS) in hypoxia-driven Stat3 activation in human glioblastoma. We found that hypoxic stress increased ROS production as well as Stat3 activation and that ROS inhibitors (diphenyleneiodonium, rotenone and myxothiazol) and an antioxidant (N-acetyl-L-cysteine) blocked Stat3 activation under hypoxic conditions. To determine a major route of ROS production, we tested whether nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4) is involved in hypoxia-induced ROS production. Nox4 expression was found to be increased at both mRNA and protein levels in hypoxic glioblastoma cells. In addition, siRNA-mediated knockdown of Nox4 expression abolished hypoxia induced Stat3 activation and vascular endothelial growth factor expression, which is associated with tumor cells' ability to trigger tube formation of endothelial cells in vitro. Our findings indicate that elevated ROS production plays a crucial role for Stat3 activation and angiogenesis in hypoxic glioblastoma cells.

Expression of astrocyte elevated gene-1 (AEG-1) in human meningiomas and its roles in cell proliferation and survival.

Astrocyte elevated gene-1 (AEG-1) has recently been proposed to be involved in tumor development, invasion, and metastasis in several human cancers. However, the functional importance of AEG-1 expression in human meningioma has not been determined. We investigate the level of AEG-1 expression by quantitative reverse transcription PCR, immunohistochemistry analysis, and western blotting in various human meningioma tissues and cells. To determine the suppressive effect of AEG-1 on meningioma progression, we inhibited AEG-1 expression using small interfering RNA and examined cell proliferation, apoptosis, colony formation and tumorigenicity in a mouse xenograft model. AEG-1 expression was frequently elevated at both mRNA and protein levels in meningioma tumor tissues and in meningioma-derived cells as well. This elevation was more commonly observed in high-grade tumors than in benign ones. The knockdown of AEG-1 led to a decrease in overall cell proliferation, as well as anchorage-independent growth of malignant meningioma. In addition, apoptotic cell death occurred in AEG-1 depleted meningioma cells through p-Akt and Bcl-2 suppression. Furthermore, a mouse xenograft meningioma model showed that inhibition of AEG-1 expression significantly decreased tumor growth. Altogether, these data show that the elevation of AEG-1 contributes to the malignant progression of meningiomas, suggesting that AEG-1 could be a novel therapeutic target against human meningiomas.

Romo1 is associated with ROS production and cellular growth in human gliomas.

Romo1 is a mitochondrial protein whose elevated expression is commonly observed in various types of human cancers. However, the expression status of Romo1 and its implication in the pathogenesis of human glioblastoma (GBM) remain largely undefined. To understand the role of Romo1 in the progression of GBM, we explored its expression in a series of GBM tissues and cell lines and determined its effect on ROS production, cell proliferation, and tumor growth. Romo1 was frequently overexpressed at the mRNA level in both primary tumors and cell lines and its elevation was more commonly observed in high grade tumors versus low grade tumors. Romo1 expression was associated with ROS production and its knockdown led to a marked reduction of in vitro cellular growth and anchorage-independent growth of GBM. Consistently, Romo1 depletion induced a G2/M arrest of the cell cycle that was accompanied with accumulation of phospho-cdc2. Furthermore, a mouse xenograft assay revealed that Romo1 depletion significantly decreased tumor formation and growth. Therefore, our data demonstrate that Romo1 upregulation is a common event in human GBMs and contributes to the malignant tumor progression, suggesting that Romo1 could be a new therapeutic target for human GBM.

Prognostic Factors of Clinical Outcomes in Patients with Spontaneous Thalamic Hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) is a well-known condition, but ICH restricted to the thalamus is less widely studied. We investigated the prognostic factors of thalamic ICHs. MATERIAL AND METHODS: Seventy patients from January 2009 to November 2014 were retrospectively reviewed. Patients who demonstrated spontaneous ICH primarily affecting the thalamus on initial brain computed tomography (CT) were enrolled. Patients were categorized into 2 groups based on their Glasgow Outcome Scale (GOS) scores. Various presumptive prognostic factors were analyzed to investigate relationships between various clinical characteristics and outcomes. RESULTS: Of the enrolled patients, 39 showed a GOS of 4-5, and were categorized as the good outcome group, while another 31 patients showed a GOS of 1-3 and were categorized as the poor outcome group. Initial GCS score, calculated volume of hematoma, presence of intraventricular hemorrhage (IVH), coexisting complications, hydrocephalus, performance of external ventricular drainage, and modified Graeb's scores of patients with IVH were significantly different between the 2 groups. In multivariate analysis, among the factors above, initial GCS score (P=0.002, Odds ratio [OR]=1.761, Confidence interval [CI]=1.223-2.536) and the existence of systemic complications (P=0.015, OR=0.059, CI=0.006-0.573) were independently associated with clinical outcomes. Calculated hematoma volume showed a borderline relationship with outcomes (P=0.079, OR=0.920, CI=0.839-1.010). CONCLUSIONS: Initial GCS score and the existence of systemic complications were strong predictive factors for prognosis of thalamic ICH. Calculated hematoma volume also had predictive value for clinical outcomes.

Forkhead box M1 is regulated by heat shock factor 1 and promotes glioma cells survival under heat shock stress.

The forkhead box M1 (FoxM1) is a key transcription factor regulating multiple aspects of cell biology. Prior studies have shown that FoxM1 is overexpressed in a variety of human tumors, including brain tumor, and plays a critical role in cancer development and progression. In this study we found that FoxM1 was up-regulated by heat shock factor 1 (HSF1) under heat shock stress condition in multiple cell lines. Knockdown of HSF1 with HSF1 siRNA or inhibition of HSF1 with a HSF1 inhibitor abrogated heat shock-induced expression of FoxM1. Genetic deletion of HSF1 in mouse embryo fibroblast cells also abolished heat shock stress-induced FoxM1 expression. Moreover, we showed that HSF1 directly bound to FoxM1 promoter and increased FoxM1 promoter activity. Furthermore, we demonstrated that FoxM1 was required for the G(2)-M phase progression through regulating Cdc2, Cdc20, and Cdc25B under a mild heat shock stress but enhanced cell survival under lethal heat shock stress condition. Finally, in human glioblastoma specimens, FoxM1 overexpression correlated with elevated HSF1 expression. Our results indicate that FoxM1 is regulated by HSF1 and is critical for HSF1-mediated heat shock response. We demonstrated a novel mechanism of stress resistance controlled by HSF1 and a new HSF-FoxM1 connection that mediates cellular thermotolerance.

Risk factors of delayed surgical evacuation for initially nonoperative acute subdural hematomas following mild head injury.

BACKGROUND: Although the majority of patients with minimal acute subdural hematomas (aSDHs) can be managed conservatively, some require delayed aSDH evacuation due to hematoma enlargement. This study was designed to determine the risk factors associated with delayed hematoma enlargement leading to surgery in patients with aSDHs who did not initially require surgical intervention. METHODS: From 2002 to 2012, 98 patients were treated for nonoperative aSDHs following mild head injury (Glasgow Coma Scale scores of 13-15). The outcome variables were radiographic evidence of SDH enlargement on serially obtained computed tomography (CT) images and later surgical evacuation. Univariate and multivariate analyses were applied to both the demographic and initial radiographic features to identify risk factors for SDH progression and surgery. RESULTS: Overall, 64 patients (65 %) revealed minimal SDH or spontaneous hematoma resolution (conservative group) with conservative management at their last follow-up CT scan. The remaining 34 patients (35 %) received delayed hematoma evacuation (delayed surgery group) a median of 17 days after the head trauma. There were no significant differences between the two groups for baseline characteristics, including age, injury type, degree of brain atrophy, prior history of antithrombotic drugs, and coagulopathy. The presence of cerebral contusions and subarachnoid hemorrhages was more common in the conservative group (p = 0.003 and p = 0.003, respectively). On multivariate analysis, hematoma volume (p = 0.01, odds ratio [OR] = 1.094, 95 % confidence interval [CI] = 1.021-1.173) and degree of midline shift (p = 0.01, OR = 1.433, 95 % CI = 1.088-1.888) on the initial CT scan were independently associated with delayed hematoma evacuation. CONCLUSIONS: A critical proportion of patients with minimal aSDHs occurring after mild head injury can progress over several weeks and require hematoma evacuation. Especially patients with a large initial SDH volume and accompanying midline shift require careful monitoring of hematoma progression.

Primary Intracranial Ewing Sarcoma With an Unusual Presentation: A Case Report.

Primary extraosseous intracranial Ewing sarcoma (ES) is an extremely rare disease, limited to the pediatric population, that primarily originates in the skull. Here, we present an unusual case of adult Ewing's sarcoma originating from the brain parenchyma. The 50-year-old male patient visited our hospital with severe headache lasting 3 weeks. MRI presented 6.1×6.2×5.2 cm sized heterogeneously enhanced mass containing peritumoral edema in the right frontal lobe. The patient underwent right frontal craniotomy, at which time the gray and red masses adhered to the surrounding brain parenchyma. The mass was completely resected using neuronavigation and electrophysiological monitoring. Histopathological examination revealed ES-compatible findings of small round cell tumor and CD-99 positive membranous immunostaining. Next generation sequencing revealed translocation and fusion of EWSR1 and FLI1, consistent with a confirmed diagnosis of ES. Consequently, the patient underwent postoperative radiotherapy. The present case revealed adult primary intracranial ES arising from the frontal lobe. Although its etiology remains poorly understood, intraparenchymal ES should be included in the differential diagnosis of parenchymal brain tumors.

Corrigendum: Clinical feasibility of miniaturized Lissajous scanning confocal laser endomicroscopy for indocyanine green-enhanced brain tumor diagnosis.

[This corrects the article DOI: 10.3389/fonc.2022.994054.].

A prospective multicenter assessor blinded pilot study using confocal laser endomicroscopy for intraoperative brain tumor diagnosis.

In this multi-center, assessor-blinded pilot study, the diagnostic efficacy of cCeLL-Ex vivo, a second-generation confocal laser endomicroscopy (CLE), was compared against the gold standard frozen section analysis for intraoperative brain tumor diagnosis. The study was conducted across three tertiary medical institutions in the Republic of Korea. Biopsy samples from newly diagnosed brain tumor patients were categorized based on location and divided for permanent section analysis, frozen section analysis, and cCeLL-Ex vivo imaging. Of the 74 samples from 55 patients, the majority were from the tumor core (74.3%). cCeLL-Ex vivo exhibited a relatively higher diagnostic accuracy (89.2%) than frozen section analysis (86.5%), with both methods showing a sensitivity of 92.2%. cCeLL-Ex vivo also demonstrated higher specificity (70% vs. 50%), positive predictive value (PPV) (95.2% vs. 92.2%), and negative predictive value (NPV) (58.3% vs. 50%). Furthermore, the time from sample preparation to diagnosis was notably shorter with cCeLL-Ex vivo (13 min 17 s) compared to frozen section analysis (28 min 28 s) (p-value < 0.005). These findings underscore cCeLL-Ex vivo's potential as a supplementary tool for intraoperative brain tumor diagnosis, with future studies anticipated to further validate its clinical utility.

Interferon regulatory factor 7 regulates glioma stem cells via interleukin-6 and Notch signalling.

Inflammatory microenvironment signalling plays a crucial role in tumour progression (i.e. cancer cell proliferation, survival, angiogenesis and metastasis) in many types of human malignancies. However, the role of inflammation in brain tumour pathology remains poorly understood. Here, we report that interferon regulatory factor 7 is a crucial regulator of brain tumour progression and heterogeneity. Ectopic expression of interferon regulatory factor 7 in glioma cells promotes tumorigenicity, angiogenesis, microglia recruitment and cancer stemness in vivo and in vitro through induction of interleukin 6, C-X-C motif chemokine 1 and C-C motif chemokine 2. In particular, interferon regulatory factor 7-driven interleukin 6 plays a pivotal role in maintaining glioma stem cell properties via Janus kinase/signal transducer and activator of transcription-mediated activation of Jagged-Notch signalling in glioma cells and glioma stem cells derived from glioma patients. Accordingly, the short hairpin RNA-mediated depletion of interferon regulatory factor 7 in glioma stem cells markedly suppressed interleukin 6-Janus kinase/signal transducer and activator of transcription-mediated Jagged-Notch-signalling pathway, leading to decreases in glioma stem cell marker expression, tumoursphere-forming ability, and tumorigenicity. Furthermore, in a mouse model of wound healing, depletion of interferon regulatory factor 7 suppressed tumour progression and decreased cellular heterogeneity. Finally, interferon regulatory factor 7 was overexpressed in patients with high-grade gliomas, suggesting its potential as an independent prognostic marker for glioma progression. Taken together, our findings indicate that interferon regulatory factor 7-mediated inflammatory signalling acts as a major driver of brain tumour progression and cellular heterogeneity via induction of glioma stem cell genesis and angiogenesis.

The significance of decompressive craniectomy for older patients with traumatic brain injury: a propensity score matching analysis from large multi-center data.

The efficacy of decompressive craniectomy (DC) for traumatic brain injury (TBI) have been investigated in two recent randomized clinical trials (RCTs) and DC is recommended as an optional treatment for improving overall survival compared to medical treatment. However, the two RCTs enrolled extremely young adults, and the efficacy of DC in older adults remains questionable. Therefore, to identify the efficacy of DC in older adults, we compared patients who received medical care with those who underwent DC after propensity score matching (PSM). From the Korea Multi-center Traumatic Brain Injury Database, 443 patients identified as having intracranial hypertension and a necessity of DC were retrospectively enrolled. The patients were classified into the DC (n = 375) and non-DC (n = 68) groups according to operation records. The PSM was conducted to match the patients in the DC group with those receiving medical care (non-DC). After PSM, the newly matched group (DC, n = 126) was compared with patients without DC (non-DC, n = 63). The mean difference in the logit of the propensity scores (LPS) was 0.00391 and the mean age of enrolled patients were 65 years. The results of the comparative analyses after PSM showed that the 6-month mortality rate of the non-DC group was higher than that of the DC group (61.9% vs. 51.6%, p = 0.179). In terms of favorable outcomes (modified Rankin Scale [mRS] score < 4), the DC group showed a lower rate of favorable mRS scores (11.9% vs. 17.5%, p = 0.296) than the non-DC group.

Recurrence of Rathke's Cleft Cyst Following Surgery and Histopathological Considerations for Recurrence: A Case Presentation.

Recurrence of Rathke's cleft cysts (RCC) following surgery is not uncommon. We present a 33-year-old male patient with chronic headache and visual disturbances whose MRI showed mostly cystic, suprasellar mass with peripheral enhancement. Endoscopic extended transsphenoidal approach and tumor resection was performed and RCC was pathologically confirmed postoperatively. Early recurrence was first suspected at 3 months following surgery, and his serial MRIs showed a recurred mass without associated clinical symptoms. Upon further histopathological study, extensive squamous metaplasia and high Ki-67 were seen. Also, in this study, we discuss important factors associated with cyst recurrence following surgery.

The Study of a Validated Assessment Scale for a Localized Submental Fat Volume.

BACKGROUND: This aim of this study was to develop an objective tool for rating submental fat applied to Koreans. METHODS: The study was conducted between April 2019 and October 2019. A total of 92 subjects were enrolled in the study. Clinical photos of the subjects were categorized using validated CR-SMFRS by three plastic surgeons and one dermatologist. The categorized photos were then shown to six different plastic surgeons for evaluation. RESULTS: The Cohen's kappa value for the six raters were 0.830, 0.742, 0.703, 0.907, 0.862, and 0.793 with statistical significance (p < 0.001). ICC value was between 0.860 and 0.966 (p < 0.001). Since the Cohen's value and ICC were above 0.6 for all raters, the ratings performed by all six raters were used in the analysis. The ICC values between raters were between 0.899 and 0.902. CONCLUSIONS: We came up with a set of reference photos that can be used for submental fat rating scale applicable to Korean subjects. LEVEL OF EVIDENCE: II.

Comparison of cerebrospinal fluid biomarkers between idiopathic normal pressure hydrocephalus and subarachnoid hemorrhage-induced chronic hydrocephalus: a pilot study.

BACKGROUND: We examined the cerebrospinal fluid (CSF) markers of subarachnoid hemorrhage (SAH)-induced and idiopathic normal pressure hydrocephalus (INPH) to investigate the pathophysiology and mechanism of communicating hydrocephalus compared to obstructive hydrocephalus. MATERIAL/METHODS: We obtained CSF samples from 8 INPH, 10 SAH-induced hydrocephalus, and 6 unmatched patients with non-hemorrhagic obstructive hydrocephalus during their ventriculoperitoneal shunt operations. Transforming growth factor (TGF)-ß1, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), and total tau in the CSF were analyzed via enzyme-linked immunosorbent assay. RESULTS: The mean VEGF levels in the CSF of patients with SAH-induced hydrocephalus, INPH, and obstructive hydrocephalus were 239 ± 131, 239 ± 75, and 163 ± 122 pg/mL, respectively. The total tau concentrations in the CSF of the groups were 1139 ± 1900, 325 ± 325, and 1550 ± 2886 pg/mL, respectively. TNF-α values were 114 ± 34, 134 ± 38, and 55 ± 16 pg/mL, respectively. TGF-ß1 values were 953 ± 430, 869 ± 447, and 136 ± 63 pg/mL, respectively. A significant difference in TNF-α and TGF-ß1 levels was observed only between SAH-induced and chronic obstructive hydrocephalus, and between INPH and chronic obstructive hydrocephalus (p<0.01). CONCLUSIONS: No significant differences in the 4 CSF biomarker levels were observed between INPH and SAH-induced hydrocephalus, whereas CSF TNF-α and TGF-ß1 levels were increased compared to those in patients with chronic obstructive hydrocephalus. Post-SAH hydrocephalus and INPH are probably more destructive to neural tissues, and then stimulate the inflammatory reaction and healing process, compared with obstructive hydrocephalus.

XAF1 directs glioma response to temozolomide through apoptotic transition of autophagy by activation of ATM-AMPK signaling.

Background: X-linked inhibitor of apoptosis-associated factor 1 (XAF1) is a tumor suppressor that is commonly inactivated in multiple human cancers. However, its role in the pathogenesis and therapeutic response of glioma is poorly characterized. Methods: XAF1 activation by temozolomide (TMZ) and its effect on TMZ cytotoxicity were defined using luciferase reporter, flow cytometry, and immunofluorescence assays. Signaling mechanism was analyzed using genetic and pharmacologic experiments. In vivo studies were performed in mice to validate the role of XAF1 in TMZ therapy. Results: Epigenetic alteration of XAF1 is frequent in cell lines and primary tumors and contributes to cancer cell growth. XAF1 transcription is activated by TMZ via JNK-IRF-1 signaling to promote apoptosis while it is impaired by promoter hypermethylation. In tumor cells expressing high O 6-methylguanine-DNA methyltransferase (MGMT), XAF1 response to TMZ is debilitated. XAF1 facilitates TMZ-mediated autophagic flux to direct an apoptotic transition of protective autophagy. Mechanistically, XAF1 is translocated into the mitochondria to stimulate reactive oxygen species (ROS) production and ataxia telangiectasia mutated (ATM)-AMP-activated protein kinase (AMPK) signaling. A mutant XAF1 lacking the zinc finger 6 domain fails to localize in the mitochondria and activate ROS-ATM-AMPK signaling and autophagy-mediated apoptosis. XAF1-restored xenograft tumors display a reduced growth rate and enhanced therapeutic response to TMZ, which is accompanied with activation of ATM-AMPK signaling. XAF1 expression is associated with overall survival of TMZ treatment patients, particularly with low MGMT cancer. Conclusions: This study uncovers an important role for the XAF1-ATM-AMPK axis as a linchpin to govern glioma response to TMZ therapy.