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Abstract Background The mechanism by which glioblastoma evades temozolomide (TMZ)-induced cytotoxicity is largely unknown. We hypothesized that mitochondria plays a role in this process. Methods RNA transcriptomes were obtained from tumor samples and online databases. Expression of different proteins was manipulated using RNA interference or gene amplification. Autophagic activity and mitochondrial metabolism was assessed in vitro using the respective cellular and molecular assays. In vivo analysis were also carried out in this study. Results High SH3GLB1 gene expression was found to be associated with higher disease grading and worse survival profiles. Single-cell transcriptome analysis of clinical samples suggested that SH3GLB1 and the altered gene levels of oxidative phosphorylation (OXPHOS) were related to subsets expressing a tumor-initiating cell signature. The SH3GLB1 protein was regulated by promoter binding with Sp1, a factor associated with TMZ resistance. Downregulation of SH3GLB1 resulted in retention of TMZ susceptibility, upregulated p62, and reduced LC3B-II. Autophagy inhibition by SH3GLB1 deficiency and chloroquine resulted in attenuated OXPHOS expression. Inhibition of SH3GLB1 in resistant cells resulted in alleviation of TMZ-enhanced mitochondrial metabolic function, such as mitochondrial membrane potential, mitochondrial respiration, and ATP production. SH3GLB1 modulation could determine tumor susceptibility to TMZ. Finally, in animal models, resistant tumor cells with SH3GLB1 knockdown became resensitized to the anti-tumor effect of TMZ, including the suppression of TMZ-induced autophagy and OXPHOS. Conclusions SH3GLB1 promotes TMZ resistance via autophagy to alter mitochondrial function. Characterizing SH3GLB1 in glioblastoma may help develop new therapeutic strategies against this disease in the future.

A 50-year-old male presented to the emergency room after experiencing sudden right upper limb facial numbness and dysphasia, followed by full recovery. A brain CT scan showed hyperdense lesions within the left hemispheric sulcus, which raised suspicion of spontaneous subarachnoid hemorrhage. A T1-weighted MRI showed multiple tiny leptomeningeal enhancements in the same area, and a digital subtraction angiography showed no signs of vascular abnormality. Cerebrospinal fluid cytology revealed atypical melanin-containing cells with minimal pleomorphism. One month later, the patient developed sixth nerve palsy, which was determined to be due to intracranial hypertension. Multiple giant nevi on the legs, trunk, and scalp were also observed. A skin biopsy showed well-defined and symmetrical proliferation of melanocytic nevus cell nests in the dermis. An open biopsy was performed due to the suspicious leptomeningeal lesions, which surprisingly revealed diffuse and thick black-colored tissue infiltration of the leptomeninges. Pathology confirmed the diagnosis of meningeal melanocytosis. A ventriculoperitoneal shunt was then placed, and the patient’s neurological symptoms gradually improved. Based on the presence of multiple giant nevi on the patient’s skin and the finding of diffuse meningeal melanocytosis during the open biopsy, the patient was diagnosed with neurocutaneous melanosis. The patient received 6 cycles triweekly of Ipilimumab and Nivolumab 8 months after initial diagnosis. Unfortunately, the disease progressed and the patient passed away 14 months after initial diagnosis.

Managing acute innominate artery (IA) dissection associated with severe stenosis is challenging due to its rarity, possible complex dissection patterns, and compromised blood flow to the brain and upper extremities. This report describes our treatment strategy for this challenging disease using the kissing stent technique. A 61-year-old man had worsening of an acute IA dissection secondary to an extension of a treated aortic dissection. Four possible treatment strategies for kissing stent placement were proposed based on different approaches (open surgical or endovascular) and accesses (trans-femoral, trans-brachial, or trans-carotid access). We chose to place two stents simultaneously via a percutaneous retrograde endovascular approach through the right brachial artery and a combined open surgical distal clamping of the common carotid artery with a retrograde endovascular approach through the carotid artery. This hybrid approach strategy highlights the three key points for maintaining safety and efficacy: (1) good guiding catheter support is obtainable through retrograde, rather than antegrade, access to the lesion, (2) concomitant cerebral and upper extremity reperfusion is guaranteed by placing kissing stents into the IA, and (3) peri-procedural cerebral emboli are prevented by surgical exposure of the common carotid artery with distal clamping.

Abstract Background Glioblastoma multiforme (GBM) is one of the most aggressive malignant brain tumors. Intracranial GBM metastases to the spine are rarely detected clinically. Secondary gliosarcomas after treatment of primary GBM are rarely described. Case presentation Herein, we report the case of a 53-year-old woman who presented to our emergency room with progressive headache and weakness on the left side. Plain computed tomography and contrast magnetic resonance imaging of the brain revealed an approximately 6.8 cm × 4.5 cm right temporoparietooccipital intraaxial cystic tumor with surrounding diffuse perifocal edema that caused midline shift toward the left. Emergency craniotomy was performed to remove the tumor, and pathological examination revealed GBM. The patient received proton beam therapy, Gliadel implantation, and oral temozolomide chemotherapy as well as targeted therapy with bevacizumab. Approximately 15 months after diagnosis, she underwent surgical resection of the right temporal recurrent tumor and was newly diagnosed as having a metastatic spinal tumor. Pathologically, the right temporal and metastatic spinal tumors were gliosarcoma and GBM, respectively. Conclusions Concurrent spinal metastasis and gliosarcomatous transformation, which are two types of GBM complications, are rare. To our knowledge, this is the first report of a case of recurrent GBM with gliosarcoma after proton bean therapy.

Abstract Background Intratumor subsets with tumor-initiating features in glioblastoma are likely to survive treatment. Our goal is to identify the key factor in the process by which cells develop temozolomide (TMZ) resistance. Methods Resistant cell lines derived from U87MG and A172 were established through long-term co-incubation of TMZ. Primary tumors obtained from patients were maintained as patient-derived xenograft for studies of tumor-initating cell (TIC) features. The cell manifestations were assessed in the gene modulated cells for relevance to drug resistance. Results Among the mitochondria-related genes in the gene expression databases, superoxide dismutase 2 (SOD2) was a significant factor in resistance and patient survival. SOD2 in the resistant cells functionally determined the cell fate by limiting TMZ-stimulated superoxide reaction and cleavage of caspase-3. Genetic inhibition of the protein led to retrieval of drug effect in mouse study. SOD2 was also associated with the TIC features, which enriched in the resistant cells. The CD133+ specific subsets in the resistant cells exhibited superior superoxide regulation and the SOD2-related caspase-3 reaction. Experiments applying SOD2 modulation showed a positive correlation between the TIC features and the protein expression. Finally, co-treatment with TMZ and the SOD inhibitor sodium diethyldithiocarbamate trihydrate in xenograft mouse models with the TMZ-resistant primary tumor resulted in lower tumor proliferation, longer survival, and less CD133, Bmi-1, and SOD2 expression. Conclusion SOD2 plays crucial roles in the tumor-initiating features that are related to TMZ resistance. Inhibition of the protein is a potential therapeutic strategy that can be used to enhance the effects of chemotherapy. Graphical abstract

Glioblastoma multiforme (GBM) is a highly malignant type of brain tumor found in humans. GBM cells reproduce quickly, and the median survival time for patients after therapy is approximately 1 year with a high relapse rate. Current therapies and diagnostic tools for GBM are limited; therefore, we searched for a more favorable therapeutic target or marker protein for both therapy and diagnosis. We used mass spectrometry (MS) analysis to identify GBM‐associated marker proteins from human plasma and GBM cell cultures. Additional plasma and 52 brain tissues obtained from patients with gliomas were used to validate the association rate of serum amyloid A1 (SAA1) in different grades of gliomas and its distribution in tumors. Microarray database analysis further validated the coefficient of SAA1 levels in gliomas. The cellular mechanisms of SAA1 in GBM proliferation and infiltration were investigated in vitro. We analyzed the correlation between SAA1 and patients' medication requirement to demonstrate the clinical effects of SAA1 in GBM. SAA1 was identified from MS analysis, and its level was revealed to be correlated with the disease grade, clinical severity, and survival rate of patients with gliomas. In vitro cultures, including GBM cells and normal astrocytes, revealed that SAA1 promotes cell migration and invasion through integrin αVβ3 to activate the Erk signaling pathway. Magnetic resonance imaging and tumor region‐specific microarray analysis identified a correlation between SAA1 and GBM cell infiltration in patients. In summary, our results demonstrate that SAA1 in combination with integrin αV and β3 can serve as an indicator of high glioblastoma risk. We also identified the cellular mechanisms of SAA1 contributing to GBM progression, which can serve as the basis for future GBM therapy.

Abstract Studies on the aberrant control of extracellular matrices (ECMs) have mainly focused on the role of malignant cells but less on that of stromal fibroblasts during cancer development. Herein, by using paired normal and prostate cancer-associated stromal fibroblasts (CAFs) derived from a coculture cell model and clinical patient samples, we demonstrated that although CAFs promoted prostate cancer growth, matrix metalloproteinase-3 (MMP-3) was lower in CAFs but elevated in prostate cancer cells relative to their normal counterparts. Furthermore, hydrogen peroxide was characterized as the central modulator for altered MMP-3 expression in prostate cancer cells and CAFs, but through different regulatory mechanisms. Treatment of CAFs but not prostate cancer cells with hydrogen peroxide directly inhibited mmp-3 promoter activity with concomitant nuclear translocation of nuclear factor-κB (NF-κB), indicating that NF-κB is the downstream pathway for the transcriptional repression of MMP-3 in CAFs. Hydrogen peroxide reduced thrombospondin 2 (an MMP-3 suppressor) expression in prostate cancer cells by upregulating microRNA-128. To the best of our knowledge, this is the first study to demonstrate the crucial role of reactive oxygen species in the switching expression of MMP-3 in stromal fibroblasts and prostate cancer cells during tumor progression, clarifying how the tumor microenvironment modulates ECM homeostasis control.

Background: Malignant gliomas (MGs) are highly chemotherapy-resistant. Temozolomide (TMZ) and carmustine (BiCNU) are alkylating agents clinically used for treating MGs. However, their effectiveness is restrained by overexpression of the DNA repair protein O 6 -methylguanine-DNA methyltransferase (MGMT) in tumors. O 6 -benzylguanine (O 6 -BG) is a nonreversible inhibitor of MGMT, it promotes the cytotoxicity of alkylating chemotherapy. The authors have developed a hybrid-structured nanofibrous membrane (HSNM) that sequentially delivers high concentrations of O 6 -BG, BiCNU, and TMZ in an attempt to provide an alternative to the current therapeutic options for MGs. Methods: The HSNMs were implanted onto the cerebral surface of pathogen-free rats following surgical craniectomy, while the in vivo release behaviors of O 6 -BG, TMZ, and BiCNU from the HSNMs were explored. Subsequently, the HSNMs were surgically implanted onto the brain surface of two types of tumor-bearing rats. The survival rate, tumor volume, malignancy of tumor, and apoptotic cell death were evaluated and compared with other treatment regimens. Results: The biodegradable HSNMs sequentially and sustainably delivered high concentrations of O 6 -BG, BiCNU, and TMZ for more than 14 weeks. The tumor-bearing rats treated with HSNMs demonstrated therapeutic advantages in terms of retarded and restricted tumor growth, prolonged survival time, and attenuated malignancy. Conclusion: The results demonstrated that O 6 -BG potentiates the effects of interstitially transported BiCNU and TMZ. Therefore, O 6 -BG may be required for alkylating agents to offer maximum therapeutic benefits for the treatment of MGMT-expressing tumors. In addition, the HSNM-supported chemoprotective gene therapy enhanced chemotherapy tolerance and efficacy. It can, therefore, potentially provide an improved therapeutic alternative for MGs.

An estrogen deficiency is the main cause of osteoporosis in postmenopausal women. In bone remodeling, estrogen receptors (ERs) can mediate estrogen-transducing signals. Methylpiperidinopyrazole (MPP) is a highly specific antagonist of ER-alpha (ERα). This study was designed to evaluate the effects of MPP on estrogen-induced energy production, subsequent osteoblast maturation, and the possible mechanisms. Exposure of primary osteoblasts isolated from neonatal rat calvarias to MPP did not affect cell morphology or survival. Estradiol can induce translocation of ERα into mitochondria from the cytoplasm. Interestingly, pretreatment of rat calvarial osteoblasts with MPP lowered estrogen-induced ERα translocation. Sequentially, estrogen-triggered expressions of mitochondrial energy production-linked cytochrome c oxidase (COX) I and COX II messenger (m)RNAs were inhibited following pretreatment with MPP. Consequently, MPP caused decreases in estrogen-triggered augmentation of the activities of mitochondrial respiratory complex enzymes and levels of cellular adenosine phosphate (ATP). During progression of osteoblast maturation, estrogen induced bone morphogenetic protein (BMP)-6 and type I collagen mRNA expressions, but MPP treatment inhibited such induction. Consequently, estrogen-induced osteoblast activation and mineralization were attenuated after exposure to MPP. Taken together, MPP suppressed estrogen-induced osteoblast maturation through decreasing chromosomal osteogenesis-related BMP-6 and type I collagen mRNA expressions and mitochondrial ATP synthesis due to inhibiting energy production-linked COX I and II mRNA expressions. MPP can appropriately be applied to evaluate estrogen-involved bioenergetics and osteoblast maturation.

Malignant glioma (MG) is extremely aggressive and highly resistant to chemotherapeutic agents. Using electrospraying, the potent chemotherapeutic agent 7-ethyl-10-hydroxycamptothecia (SN-38) was embedded into 50:50 biodegradable poly[(d,l)-lactide-co-glycolide] (PLGA) microparticles (SMPs). The SMPs were stereotactically injected into the brain parenchyma of healthy rats and intratumorally injected into F98 glioma-bearing rats for estimating the pharmacodynamics and therapeutic efficacy. SN-38 was rapidly released after injection and its local (brain tissue) concentration remained much higher than that in the blood for more than 8 weeks. Glioma-bearing rats were divided into three groups—group A (n = 13; stereotactically injected pure PLGA microparticles), group B (n = 12; stereotactically injected Gliadel wafer and oral temozolomide), and group C (n = 13; stereotactic and intratumoral introduction of SMPs). The SMPs exhibited significant therapeutic efficacy, with prolonged survival, retarded tumor growth, and attenuated malignancy. The experimental results demonstrated that SMPs provide an effective and potential strategy for the treatment of MG.

Background and Purpose: A rat model of jugular venous reflux (JVR) is widely used in studies of cerebral arteriovenous fistula, cerebral venous hypertension and chronic cerebral hypoperfusion. However, methods to validate the effectiveness of the operation are needed. Methods: We performed neck 3-dimensional time-of-flight magnetic resonance angiography (MRA) with a clinical scanner in a rat model of JVR before and after the operation. High-resolution arterial angiography of the rat neck was acquired with maximum intensity projection. Results: In the JVR model, the success of the operation was validated by enhanced venous structures on MRA. The angiogram also provided information on the height of JVR and the status of other neck vessels. Conclusions: In conclusion, neck 3-dimensional time-of-flight MRA is a useful noninvasive method for monitoring the blood flow in multiple cerebral vessels in this animal model. It also revealed the height of JVR, collateral development and changes in vessels over time in longitudinal studies. This information should be considered in the evaluation of the animal model. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Traumatic aneurysms of the anterior cerebral artery (ACA) were retrospectively reviewed in an effort to identify patients at high risk of ACA aneurysm. Methods: Blunt craniofacial trauma patients featuring vascular injuries over the region of the ACA were studied. Results: Six patients featuring eight ACA aneurysms were diagnosed between June 1992 and December 2005, inclusively. Seven aneurysms were located at nonbranched sites and one was located over the right ACA-anterior communicating artery junction. One patient died immediately of massive intracranial lobar hemorrhage (ICH). The other 5 patients experienced rebleeding during a period of from 1 to 29 days. Brain computed tomography revealed subarachnoid hemorrhage (SAH) in 1 of these 6 patients, ICH over the medial frontal area or cingulated gyrus in 4 patients, intraventricular hemorrhage (IVH) in 3 patients, and an interhemispheric subdural hematoma (SDH) in 2 patients. Conclusion: Delayed-onset deterioration of neurological deficit is the most common clinical presentation of traumatic ACA aneurysms. Midline hemorrhage such as medial frontal hemorrhage or cingulate gyrus hemorrhage, and the presence of an interhemispheric SDH associated with SAH and IVH subsequent to blunt craniofacial trauma should be further evaluated, as they pre-sent a high risk of traumatic ACA aneurysms to patients. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]