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1.
Int J Mol Sci ; 24(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37686174

RESUMO

Glioblastoma (GBM) is the most common primary brain malignancy in adults. Despite multimodal treatment that involves maximal safe resection, concurrent chemoradiotherapy, and tumour treatment for supratentorial lesions, the prognosis remains poor. The current median overall survival is only <2 years, and the 5-year survival is only 7.2%. Thioredoxin domain-containing protein 11 (TXNDC11), also known as EF-hand binding protein 1, was reported as an endoplasmic reticulum stress-induced protein. The present study aimed to elucidate the prognostic role of TXNDC11 in GBM. We evaluated the clinical parameters and TXNDC11 scores in gliomas from hospitals. Additionally, proliferation, invasion, migration assays, apoptosis, and temozolomide (TMZ)-sensitivity assays of GBM cells were conducted to evaluate the effects of short interfering RNA (siRNA) on these processes. In addition, these cells were subjected to Western blotting to detect the expression levels of N-cadherin, E-cadherin, and Cyclin D1. High levels of TXNDC11 protein expression were significantly associated with World Health Organization (WHO) high-grade tumour classification and poor prognosis. Multivariate analysis revealed that in addition to the WHO grade, TXNDC11 protein expression was also an independent prognostic factor of glioma. In addition, TXNDC11 silencing inhibited proliferation, migration, and invasion and led to apoptosis of GBM cells. However, over-expression of TXNDC11 enhanced proliferation, migration, and invasion. Further, TXNDC11 knockdown downregulated N-cadherin and cyclin D1 expression and upregulated E-cadherin expression in GBM cells. Knock-in TXNDC11 return these. Finally, in vivo, orthotopic xenotransplantation of TXNDC11-silenced GBM cells into nude rats promoted slower tumour growth and prolonged survival time. TXNDC11 is a potential oncogene in GBMs and may be an emerging therapeutic target.


Assuntos
Glioblastoma , Glioma , Animais , Ratos , Caderinas , Ciclina D1 , Glioma/genética , Tiorredoxinas/genética , Humanos
2.
Environ Toxicol ; 38(9): 2143-2154, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37283489

RESUMO

Organophosphate pesticides (OPs), which are among the most widely used synthetic chemicals for the control of a wide variety of pests, are however associated with various adverse reactions in animals and humans. Chlorpyrifos, an OP, has been shown to cause various health complications due to ingestion, inhalation, or skin absorption. The mechanisms underlying the adverse effect of chlorpyrifos on neurotoxicity have not been elucidated. Therefore, we aimed to determine the mechanism of chlorpyrifos-induced cytotoxicity and to examine whether the antioxidant vitamin E (VE) ameliorated these cytotoxic effects using DBTRG-05MG, a human glioblastoma cell line. The DBTRG-05MG cells were treated with chlorpyrifos, VE, or chlorpyrifos plus VE and compared with the untreated control cells. Chlorpyrifos induced a significant decrease in cell viability and caused morphological changes in treated cultures. Furthermore, chlorpyrifos led to the increased production of reactive oxygen species (ROS) accompanied by a decrease in the level of reduced glutathione. Additionally, chlorpyrifos induced apoptosis by upregulating the protein levels of Bax and cleaved caspase-9/caspase-3 and by downregulating the protein levels of Bcl-2. Moreover, chlorpyrifos modulated the antioxidant response by increasing the protein levels of Nrf2, HO-1, and NQO1. However, VE reversed the cytotoxicity and oxidative stress induced by chlorpyrifos treatment in DBTRG-05MG cells. Overall, these findings suggest that chlorpyrifos causes cytotoxicity through oxidative stress, a process that may play an important role in the development of chlorpyrifos-associated glioblastoma.


Assuntos
Antioxidantes , Clorpirifos , Inseticidas , Vitamina E , Animais , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Apoptose , Clorpirifos/toxicidade , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Vitamina E/farmacologia , Inseticidas/toxicidade , Linhagem Celular Tumoral , Caspase 9/metabolismo , Caspase 3/metabolismo
3.
Toxicon ; 221: 106957, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36374720

RESUMO

Mycotoxins are secondary metabolites produced by various kinds of fungi that can induce disease in humans. The fungal species Penicillium expansum produces patulin (C7H6O4), a polyketide lactone mycotoxin found in fruits. Patulin is classified as noncarcinogen; however, recently, it has been associated with harmful effects on the central nervous system. Patulin's toxic action has been established in various brain models; however, its effect on human glioblastoma remains elusive. This study explores whether patulin induces cytotoxicity through oxidative stress in DBTRG-05MG human glioblastoma cells. This study also evaluates whether the antioxidant N-acetylcysteine (NAC) protects against patulin-induced cytotoxicity. In DBTRG-05MG cells, patulin concentration (10-60 µM) dependently induced cytotoxicity. Concerning oxidative stress, patulin (10 and 20 µM) increased the production of intracellular reactive oxygen species (ROS) but depleted reduced glutathione (GSH) contents and regulated the expressions of antioxidant-related proteins (Nrf2 and HO-1). Furthermore, patulin induced cytotoxicity via modulation of apoptosis-related protein expressions (Bax, cleaved caspase-9, and cleaved caspase-3). These cytotoxic responses were partially reversed via pretreatment with NAC (10 µM). In summary, these data help us understand the toxicology of patulin in human glioblastoma and evaluate whether NAC could clinically reduce patulin-affected brain damage.


Assuntos
Glioblastoma , Patulina , Humanos , Patulina/toxicidade , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
4.
Quant Imaging Med Surg ; 12(1): 558-567, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34993101

RESUMO

BACKGROUND: Susceptibility-weighted imaging (SWI) is sensitive to the accumulation of paramagnetic substances, such as hemorrhage and increased venous vasculature, both being frequently found in high-grade tumors. The purpose of this retrospective study is to differentiate high-grade and low-grade astrocytoma by objectively measuring quantitative intra-tumoral susceptibility signals (qITSS) on SWI. METHODS: Precontrast SWI and 3D contrast-enhanced T1WI of 65 patients with astrocytoma were collected at 1.5 Tesla. All tumors were histologically confirmed and classified into two groups: high grade (WHO grade III and IV, n=50) and low grade (WHO grade II, n=15). After manual delineation of the tumor on T1WI, normalized contrast (NC) was calculated voxel by voxel within the tumor by using the concept of contrast to noise ratio. Thresholding on NC was applied to detect qITSS, and the volumetric percentage of qITSS can be obtained for each tumor. Two-sample t-test was applied to examine significant difference of qITSS percentage between high-grade and low-grade astrocytoma for different NC thresholds, ranging from 4 to 20. Receiver operating characteristic analysis was performed to evaluate the performance of differentiation. RESULTS: P value was less than 0.01 for a large range of NC thresholds [4-20], reflecting significant difference of qITSS percentage between high-grade and low-grade astrocytoma. The area under the receiver operating characteristic curve was larger than 0.9 at NC thresholds from 8 to 16 and peaks at 0.949 with a NC threshold of 14. It was shown that astrocytoma grading by qITSS percentage is successful for a wide range of NC threshold, demonstrating robustness on threshold selection. CONCLUSIONS: Without relying on the selection of slice position and at the same time providing objective identification of hypointense signal in SWI, the qITSS percentage can be used to distinguish high-grade and low-grade astrocytoma reliably.

5.
World Neurosurg ; 158: 205-209, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34839047

RESUMO

OBJECTIVE: Ependymomas are rare central nervous system tumors. The current treatment strategy is gross total tumor removal. Whether adjuvant therapy will be beneficial is controversial. We retrospectively analyzed 3 cases of World Health Organization (WHO) grade III posterior fossa anaplastic ependymomas treated with different treatment modalities. We aimed to identify possible treatment options for infratentorial WHO grade III anaplastic ependymoma in adults. METHODS: We performed a retrospective analysis of 3 patients diagnosed with infratentorial anaplastic ependymomas in our institution from 2016 to 2020. The demographic data were documented. This case series of 3 patients does not meet the Department of Health and Human Services definition of research and does not need Institutional Review Board approval. All patients' informed consents have been obtained. RESULTS: One patient underwent subtotal tumor resection combined with adjuvant radiotherapy and Gamma Knife radiosurgery while the other 2 patients underwent gross total tumor removal combined with Gamma Knife radiosurgery or adjuvant radiotherapy. Tumors recurred in the first patient 20 months later, while the other 2 patents did not develop recurrence. The modified Rankin scale scores of these patients were 1, 0, and 0. All patients are followed up with regular magnetic resonance imaging at our facility. CONCLUSIONS: The strategy for treating WHO grade III anaplastic ependymomas is controversial, but gross total tumor resection remains the key element. Adjuvant stereotactic radiosurgery after tumor removal might be considered if radiotherapy is not an option. The role of chemotherapy is unclear, and the use of chemotherapy should be tailored to individual patients.


Assuntos
Ependimoma , Neoplasias Infratentoriais , Adulto , Ependimoma/diagnóstico por imagem , Ependimoma/cirurgia , Humanos , Neoplasias Infratentoriais/diagnóstico por imagem , Neoplasias Infratentoriais/cirurgia , Radioterapia Adjuvante , Estudos Retrospectivos
6.
Surg Neurol Int ; 11: 414, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33365177

RESUMO

BACKGROUND: Intracranial solitary fibrous tumor/hemangiopericytoma (HPC) is a rare and aggressive tumor. We conducted this retrospective study to investigate the outcome of patients after treatment, the efficacy of postoperative adjuvant radiotherapy, and the factors not conducive to total resection. METHODS: We conducted a retrospective review of the medical records of patients harboring fresh intracranial solitary fibrous tumor/HPC treated from January 2009 to December 2019 in our hospital. We reviewed their clinical presentations, radiologic appearances, tumor size and location, extent of resection, estimate intraoperative blood loss, treatment modalities and results, and duration of follow-up. RESULTS: There were seven consecutive patients (three males and four females). The ages of the patients at the time of diagnosis ranged from 35 to 77 years (mean: 52.86 years). Five patients (71.43%) got tumor bigger than 5 cm in dimension and only 1 patient (14.29%) underwent gross total tumor resection in the first operation without complication. Five patients (71.43%) underwent postoperative adjuvant radiotherapy. Follow-up period ranged from 4.24 to 123.55 months and the median follow-up period was 91.36 months. Three patients had favorable outcome with Glasgow Outcome Scale (GOS) equal to 4; four patients had unfavorable outcome with GOS equal to 2 or 3. No mortality was happened. CONCLUSION: Gross total tumor resection in the initial surgery is very important to achieve a better outcome. Massive intraoperative bleeding and venous sinus or major vessels adjoining are factors not conducive to total resection. Radiotherapy can be administered as adjuvant therapy for cases showing an aggressive phenotype or not treated with gross total resection.

7.
Eur J Radiol ; 117: 56-61, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31307653

RESUMO

PURPOSE: The purpose of this retrospective study was to investigate the differentiation of abscess and necrotic tumors, using susceptibility-weighted imaging (SWI) and apparent diffusion coefficients (ADC) either separated or combined. METHODS: Imaging was performed on 26 patients with pyogenic brain abscesses, 31 patients with rim-enhancing glioblastomas, and 21 patients with rim-enhancing metastases. The degree of intralesional susceptibility signal (ILSS) was independently assessed by three observers. Average ADC in the lesion core was calculated. After receiver operating characteristic (ROC) analysis, the area under the ROC curve was compared using three different analytical models (ILSS, ADC, and ILSS-ADC combined) to differentiate abscess from the two rim-enhancing necrotic tumors. RESULTS: The ILSS-ADC combined model had greater area under the ROC curves than ILSS or ADC used alone. In this study, the ILSS-ADC combined model showed 100% diagnostic accuracy differentiating abscesses from glioblastoma. The ADC model and the ILSS-ADC combined model performed equally well in distinguishing abscesses from metastases. CONCLUSION: It is concluded that SWI and ADC are complementary, and the combination of SWI and ADC may improve results compared with the use of only one model. Validation by an independent cohort is the next necessary step to broaden its applicability in routine clinical settings.


Assuntos
Abscesso Encefálico/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Glioblastoma/diagnóstico por imagem , Necrose/diagnóstico por imagem , Adulto , Idoso , Abscesso Encefálico/patologia , Neoplasias Encefálicas/patologia , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/patologia , Estudos Retrospectivos
8.
Pestic Biochem Physiol ; 157: 152-160, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153463

RESUMO

Malathion, one of commonly used organophosphate insecticides, has a wide range of toxic actions in different models. However, the effect of this compound on Ca2+ homeostasis and its related cytotoxicity in glial cells is elusive. This study examined whether malathion evoked intracellular Ca2+ concentration ([Ca2+]i) rises and established the relationship between Ca2+ signaling and cytotoxicity in normal human astrocytes, rat astrocytes and human glioblastoma cells. The data show that malathion induced concentration-dependent [Ca2+]i rises in Gibco® Human Astrocytes (GHA cells), but not in DI TNC1 normal rat astrocytes and DBTRG-05MG human glioblastoma cells. In GHA cells, this Ca2+ signal response was reduced by removing extracellular Ca2+. In Ca2+-free medium, pretreatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin abolished malathion-induced [Ca2+]i rises. Conversely, incubation with malathion abolished thapsigargin-induced [Ca2+]i rises. Inhibition of phospholipase C (PLC) with U73122 also blocked malathion-induced [Ca2+]i rises. In Ca2+-containing medium, malathion-induced [Ca2+]i rises was inhibited by store-operated Ca2+ channel blockers (2-APB, econazole or SKF96365) and the protein kinase C (PKC) inhibitor GF109203X. Malathion (5-25 µM) concentration-dependently caused cytotoxicity in GHA, DI TNC1 and DBTRG-05MG cells. This cytotoxic effect was partially prevented by prechelating cytosolic Ca2+ with BAPTA-AM (a selective Ca2+ chelator) only in GHA cells. Together, in GHA but not in DI TNC1 and DBTRG-05MG cells, malathion induced [Ca2+]i rises by inducing PLC-dependent Ca2+ release from the endoplasmic reticulum and Ca2+ entry via PKC-sensitive store-operated Ca2+ channels. Furthermore, malathion induced Ca2+-associated cytotoxicity, suggesting that Ca2+ chelating may have a protective effect on malathion-induced cytotoxicity in normal human astrocytes.


Assuntos
Cálcio/metabolismo , Malation/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quelantes , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Humanos , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ratos
9.
Case Rep Surg ; 2018: 1382680, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29992076

RESUMO

INTRODUCTION: Glioblastoma multiforme (GBM), the most common primary malignant brain tumor in adults, is characterized by extensive heterogeneity in its clinicopathological presentation. A primary brain tumor with both astrocytic differentiation and neuronal immunophenotype features is rare. Here, we report a long-term survival patient who presented this rare form of GBM in the disease course. PRESENTATION OF CASE: A 23-year-old woman, presenting with rapidly progressive headache and right-side weakness, was diagnosed with brain tumor over the left basal ganglion. She underwent the first craniectomy for tumor removal, and histopathology revealed classic GBM. Tumor recurrence occurred 8 years later. Another gross total resection was performed and pathology revealed GBM with the oligodendroglioma component (GBM-O). Due to disease progression, she received debulking surgery the following year. The third pathology revealed glioblastoma with primitive neuroectodermal tumor-like component (GBM-PNET). DISCUSSION: GBM-PNETs are collision tumors with both neuronal and glial components. They are rare, and a few case reports have suggested that these tumors are associated with favorable outcomes but a higher risk of cerebrospinal fluid dissemination. CONCLUSION: We report a patient who developed the distinct pathologic variants of classic GBM, GBM-O, and GBM-PNET, throughout the disease course. Young age, aggressive surgical resection, and pathologic and genetic features may have contributed to the long-term survival of the patient.

10.
Surg Neurol Int ; 9: 127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30034918

RESUMO

BACKGROUND: Giant cell tumor of bone originating from the connective tissue within the bone marrow is benign but locally aggressive lesion. In all, 90% of the cases involve the epiphysis of long bones and less than 2% involve the skull. Giant cell tumors of the skull occur most frequently in the sphenoid and temporal bones, and very rarely in the ethmoid, frontal, parietal, and occipital bones. We would like to share a case of giant cell tumor of bone arising from the left orbital roof with involving ethmoid sinus, which was diagnosed to be a meningioma before surgery. CASE DESCRIPTION: A 32-year-old lady presented to us with the chief complain of left proptosis, diplopia, and left eye soreness without decline of visual acuity for about 2 months. Her orbital magnetic resonance imaging (MRI) disclosed a mass lesion located in the left frontal base, orbital roof, and upper medial orbital region with adjacent dural-tail sign favoring meningioma. She underwent a left supraorbital pterional craniotomy with the gross total removal of tumor and dura reconstruction. Histology examination of the tumor showed a picture of giant cell tumor of bone. Considering giant cell tumor of bone is locally aggressive, postoperative adjuvant therapy with Denosumab was introduced after full explanation. CONCLUSION: Standard treatments of skull-base giant cell tumors have yet to be established due to small number of cases reported in the literature. The standard treatment of giant cell tumor of bone is complete resection of the tumor.

11.
Environ Toxicol ; 32(12): 2440-2454, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28804952

RESUMO

Propofol (2,6-diisopropylphenol), one of the extensively and commonly used anesthetic agents, has been shown to affect the biological behavior of various models. Previous researches have shown that propofol-induced cytotoxicity might cause anticancer effect in different cells. However, the mechanisms underlying the effect of propofol on cytotoxicity is still elusive in human glioblastoma cells. The aims of this study were to evaluate effects of propofol on cytotoxicity, cell cycle distribution and ROS production, and establish the relationship between oxidative stress and cytotoxicity in GBM 8401 human glioblastoma cells and DI TNC1 rat astrocytes. Propofol (20-30 µM) concentration-dependently induced cytotoxicity, cell cycle arrest, and increased ROS production in GBM 8401 cells but not in DI TNC1 cells. In GBM 8401 cells, propofol induced G2/M phase cell arrest, which affected the CDK1, cyclin B1, p53, and p21 protein expression levels. Furthermore, propofol induced oxygen stresses by increasing O2- and H2 O2 levels but treatment with the antioxidant N-acetylcysteine (NAC) partially reversed propofol-regulated antioxidative enzyme levels (superoxide dismutase, catalase, and glutathione peroxidase). Most significantly, propofol induced apoptotic effects by decreasing Bcl-2 but increasing Bax, cleaved caspase-9/caspase-3 levels, which were partially reversed by NAC. Moreover, the pancaspase inhibitor Z-VAD-FMK also partially prevented propofol-induced apoptosis. Together, in GBM 8401 cells but not in DI TNC1 cells, propofol activated ROS-associated apoptosis that involved cell cycle arrest and caspase activation. These findings indicate that propofol not only can be an anesthetic agent which reduces pain but also has the potential to be used for the treatment of human glioblastoma.


Assuntos
Antineoplásicos/farmacologia , Astrócitos/efeitos dos fármacos , Propofol/farmacologia , Acetilcisteína/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Astrócitos/citologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Inibidores de Caspase/farmacologia , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Glioblastoma , Humanos , Ratos , Espécies Reativas de Oxigênio/metabolismo
12.
Food Chem Toxicol ; 107(Pt A): 280-292, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28689919

RESUMO

Researches have been conducted to explore the biological effect of gastrodin, a natural compound extracted from the rhizome of Gastrodia elata Blume, in different models. However, the effects of gastrodin on cytotoxicity, cell cycle distribution and oxidative stress in glia cells have not been explored. The aim of this study was to investigate the cytotoxic effect of gastrodin and its mechanisms in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes. In DBTRG-05MG cells but not in CTX TNA2 cells, gastrodin (20-30 µM) induced cytotoxicity, G2/M phase cell cycle arrest and apoptosis. Regarding oxidative stress, gastrodin (20-30 µM) elevated intracellular ROS levels but reduced GSH levels. Treatment with the antioxidant NAC (10 µM) partially reversed gastrodin-altered antioxidant enzymes levels. Furthermore, gastrodin induced mitochondria-associated apoptosis. The apoptotic effects evoked by gastrodin were partially inhibited by the antioxidant NAC and the pancaspase inhibitor Z-VAD-FMK. Together, in DBTRG-05MG cells, but not in CTX TNA2 cells, gastrodin activated ROS-associated mitochondrial apoptotic pathways that involved cell cycle arrest. These data provide insight into the molecular mechanisms governing the ability of gastrodin to induce cytotoxicity in human glioblastoma cells and further suggest that gastrodin is a new potential agent for the treatment of human gliblasoma.


Assuntos
Apoptose/efeitos dos fármacos , Álcoois Benzílicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Gastrodia/química , Glioblastoma/tratamento farmacológico , Glucosídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Linhagem Celular Tumoral , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/fisiopatologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Rizoma/química , Proteína Supressora de Tumor p53/genética
13.
Chin J Physiol ; 60(3): 174-182, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28629211

RESUMO

Methoxsalen is a natural compound found in many seed plants. The effect of methoxsalen on Ca²âº- related physiology in human osteosarcoma is unclear. This study investigated the effect of methoxsalen on cytosolic free Ca²âº concentrations ([Ca²âº]i) in MG63 human osteosarcoma cells. Methoxsalen induced [Ca²âº]i rises concentration-dependently. Methoxsalen-induced Ca²âº entry was confirmed by Mn²âº-induced quench of fura-2 fluorescence. This Ca²âº entry was suppressed by nifedipine, econazole, and SKF96365. In Ca²âº-free medium, incubation with the endoplasmic reticulum Ca²âº pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) inhibited methoxsalen-evoked [Ca²âº]i rises by 96%. In contrast, incubation with methoxsalen abolished BHQ-evoked [Ca²âº]i rises. Inhibition of phospholipase C (PLC) with U73122 abolished methoxsalen-induced [Ca²âº]i rises. Methoxsalen was cytotoxic at 300-700 µM in a concentration-dependent fashion. Chelating cytosolic Ca²âº with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/acetoxymethyl ester (BAPTA/AM) did not prevent methoxsalen-induced cytotoxicity. Collectively, our data suggest that in MG63 cells, methoxsalen induced [Ca²âº]i rises by evoking PLC-dependent Ca²âº release from the endoplasmic reticulum, and Ca²âº entry via store-operated Ca²âº entry. Methoxsalen also induced Ca²âº- disassociated cell death.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Metoxaleno/farmacologia , Osteossarcoma/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Fura-2/metabolismo , Humanos , Fosfolipases Tipo C/metabolismo
14.
Toxicology ; 370: 1-19, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27640744

RESUMO

Cytochalasin B, a cell-permeable mycotoxin isolated from the fungus Phoma spp., shows a wide range of biological effects, among which its potent antitumor activity has raised great interests in different models. However, the cytotoxic activity of cytochalasin B and its underlying mechanisms have not been elucidated in breast cells. This study examined the effect of cytochalasin B on MCF 10A human breast epithelial cells and ZR-75-1 human breast cancer cells. Cytochalasin B (10-20µM) concentration-dependently induced cytotoxicity, cell cycle arrest, and [Ca2+]i rises in ZR-75-1 cells but not in MCF 10A cells. In ZR-75-1 cells, cytochalasin B triggered G2/M phase arrest through the modulation of CDK1, cyclin B1, p53, p27 and p21 expressions. The Ca2+ signal response induced by cytochalasin B was reduced by removing extracellular Ca2+ and was inhibited by the store-operated Ca2+ channel blocker 2-APB and SKF96365. In Ca2+-free medium, cytochalasin B induced Ca2+ release through thapsigargin-sensitive endoplasmic reticulum stores. Moreover, cytochalasin B increased H2O2 levels but reduced GSH levels. The apoptotic effects evoked by cytochalasin B were partially inhibited by prechelating cytosolic Ca2+ with BAPTA-AM and the antioxidant NAC. Together, in ZR-75-1 cells but not in MCF 10A cells, cytochalasin B activated Ca2+-associated mitochondrial apoptotic pathways that involved G2/M phase arrest and ROS signaling. Furthermore, cytochalasin B induced [Ca2+]i rises by releasing Ca2+ from the endoplasmic reticulum and causing Ca2+ influx through 2-APB or SKF96365-sensitive store-operated Ca2+ entry. Our findings provide new insights into the possible application of cytochalasin B in human breast cancer therapy.


Assuntos
Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Citocalasina B/farmacologia , Células Epiteliais/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Mama/citologia , Neoplasias da Mama/tratamento farmacológico , Proteína Quinase CDC2 , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina B1/genética , Ciclina B1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peróxido de Hidrogênio/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Chem Biol Interact ; 252: 61-73, 2016 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-27060209

RESUMO

Gallic acid, a polyhydroxylphenolic compound, is widely distributed in various plants, fruits and foods. It has been shown that gallic acid passes into blood brain barrier and reaches the brain tissue of middle cerebral artery occlusion rats. However, the effect of gallic acid on Ca(2+) signaling in glia cells is unknown. This study explored whether gallic acid affected Ca(2+) homeostasis and induced Ca(2+)-associated cytotoxicity in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes. Gallic acid (20-40 µM) concentration-dependently induced cytotoxicity and intracellular Ca(2+) level ([Ca(2+)]i) increases in DBTRG-05MG cells but not in CTX TNA2 cells. In DBTRG-05MG cells, the Ca(2+) response was decreased by half by removal of extracellular Ca(2+). In Ca(2+)-containing medium, gallic acid-induced Ca(2+) entry was inhibited by store-operated Ca(2+) channel inhibitors (2-APB, econazole and SKF96365). In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin abolished gallic acid-induced [Ca(2+)]i increases. Conversely, incubation with gallic acid also abolished thapsigargin-induced [Ca(2+)]i increases. Inhibition of phospholipase C with U73122 abolished gallic acid-induced [Ca(2+)]i increases. Gallic acid significantly caused cytotoxicity in DBTRG-05MG cells, which was partially prevented by prechelating cytosolic Ca(2+) with BAPTA-AM. Moreover, gallic acid activated mitochondrial apoptotic pathways that involved ROS production. Together, in DBTRG-05MG cells but not in CTX TNA2 cells, gallic acid induced [Ca(2+)]i increases by causing Ca(2+) entry via 2-APB, econazole and SKF96365-sensitive store-operated Ca(2+) entry, and phospholipase C-dependent release from the endoplasmic reticulum. This Ca(2+) signal subsequently evoked mitochondrial pathways of apoptosis that involved ROS production.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Cálcio/metabolismo , Ácido Gálico/farmacologia , Glioblastoma/tratamento farmacológico , Animais , Astrócitos/metabolismo , Neoplasias Encefálicas/metabolismo , Cátions Bivalentes/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/metabolismo , Homeostase/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
16.
Int J Surg Case Rep ; 14: 23-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26209757

RESUMO

INTRODUCTION: Primary central nervous lymphoma(PCNSL) is a rare form of non-Hodgkin lymphoma confined to the central nervous system. Most of the lesions are supratentorial and periventricular, often involving deep structures such as corpus callosum and basal ganglion. Isolated intraventricular lymphoma is rare and only a few case reports. We report, to the best of our knowledge, the seventh case of isolated PCNSL in the fourth ventricle in an immunocompetent patient. PRESENTATION OF CASE: A 61-year-old male presenting with 3 months of headache and dizziness followed with unsteady gait for days. The MR imaging of brain revealed a homogeneously enhancing lesion occupying almost the whole 4th ventricle.The tumor was removed subtotally via suboccipital craniotomy. Histopathology revealed the lesion be a diffuse large B-cell lymphoma. DISCUSSION: PCNSL is an important consideration in the differential diagnosis of intracranial mass lesion. The unusual location in surgically accessible fourth ventricle in posterior fossa, the isolation of the tumor may present a compelling indication for surgical resection. CONCLUSION: We suggest that primary lymphoma should be considered with homogenous lesions of the 4th ventricle. Also aggressive surgical resection in this surgically accessible location, instead of biopsy only, is rational.

18.
Eur Radiol ; 25(5): 1413-20, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25465712

RESUMO

OBJECTIVES: To investigate the feasibility of using susceptibility-weighted imaging (SWI) to discriminate abscesses and necrotic tumours. METHODS: Twenty-one patients with pyogenic abscesses, 21 patients with rim-enhancing glioblastomas and 23 patients with rim-enhancing metastases underwent SWI. Intralesional susceptibility signal (ILSS) was analyzed employing both qualitative (QL) and semi-quantitative (SQ) methods. Logistic regression models and receiver operating characteristic analysis were used to demonstrate the discriminating power. RESULTS: In QL analysis, ILSSs were seen in 12 of 21 abscesses, in 20 of 21 glioblastomas, and in 16 of 23 metastases. In SQ analysis, a low degree of ILSS (85.8 %) was in the majority of abscesses and a high degree of ILSS (76.2 %) was in the majority of glioblastomas. SQ model was significantly better than QL model in distinguishing abscesses from glioblastomas (P < .001). A derived ILSS cutoff grade of 1 or less was quantified as having a sensitivity of 85.7 %, specificity of 90.5 %, accuracy of 88.1 %, PPV of 90.0 %, and NPV of 86.4 % in distinguishing abscesses from glioblastomas. CONCLUSIONS: A high-grade ILSS may help distinguish glioblastomas from abscesses and necrotic metastatic brain tumours. The lack of ILSS or low-grade ILSS can be a more specific sign in the imaging diagnosis of abscesses. KEY POINTS: • ILSS of SWI can contribute to differential diagnosis of rim-enhanced mass. • Low-grade ILSS can be a more specific sign in abscesses. • High-grade ILSS may help distinguish necrotic glioblastomas from abscesses. • ILSS spreads across the four ILSS categories in metastases.


Assuntos
Abscesso Encefálico/diagnóstico , Neoplasias Encefálicas/diagnóstico , Encéfalo/patologia , Glioblastoma/diagnóstico , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/patologia , Diagnóstico Diferencial , Diagnóstico por Imagem , Estudos de Viabilidade , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/diagnóstico , Necrose/patologia , Variações Dependentes do Observador , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Toxicol Lett ; 232(1): 122-32, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25455450

RESUMO

Eugenol, a natural phenolic constituent of clove oil, has a wide range of applications in medicine as a local antiseptic and anesthetic. However, the effect of eugenol on human glioblastoma is unclear. This study examined whether eugenol elevated intracellular free Ca(2+) levels ([Ca(2+)]i) and induced apoptosis in DBTRG-05MG human glioblastoma cells. Eugenol evoked [Ca(2+)]i rises which were reduced by removing extracellular Ca(2+). Eugenol-induced [Ca(2+)]i rises were not altered by store-operated Ca(2+) channel blockers but were inhibited by the PKC inhibitor GF109203X and the transient receptor potential channel melastatin 8 (TRPM8) antagonist capsazepine. In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) abolished eugenol-induced [Ca(2+)]i rises. The phospholipase C (PLC) inhibitor U73122 significantly inhibited eugenol-induced [Ca(2+)]i rises. Eugenol killed cells which were not reversed by prechelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA-AM). Eugenol induced apoptosis through increasing reactive oxygen species (ROS) production, decreasing mitochondrial membrane potential, releasing cytochrome c and activating caspase-9/caspase-3. Together, in DBTRG-05MG cells, eugenol evoked [Ca(2+)]i rises by inducing PLC-dependent release of Ca(2+) from the endoplasmic reticulum and caused Ca(2+) influx possibly through TRPM8 or PKC-sensitive channels. Furthermore, eugenol induced the mitochondrial apoptotic pathway.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Eugenol/farmacologia , Glioblastoma/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteína Quinase C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Canais de Cátion TRPM/efeitos dos fármacos , Canais de Cátion TRPM/metabolismo , Fatores de Tempo , Fosfolipases Tipo C/metabolismo
20.
Surg Neurol Int ; 5(Suppl 4): S170-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25071942

RESUMO

BACKGROUND: The medulla oblongata is the lower half of the brainstem. It contains the cardiac, respiratory, vomiting, and vasomotor centers and deals with autonomic functions such as breathing, heartbeat, and blood pressure. Primary medulla oblongata germinoma is very rare and less than 20 cases have been reported in the English literature. CASE DESCRIPTION: A 22-year-old female without any particular past medical history presented to us in October 2012 with the chief complaint of dyspnea and frequent choking for 1 month. Neurological examination revealed lower cranial nerve palsies and nystagmus. Her brain computed tomography (CT) and brain magnetic resonance imaging (MRI) demonstrated a mass lesion at the dorsal surface of medulla oblongata with extension into the inferior fourth ventricle and foramen magnum. She underwent bilateral suboccipital craniotomy and C1 laminoplasty with the grossly total resection of the tumor. The histological examination of the tumor proved germinoma. Postoperative adjuvant radiotherapy was arranged. The latest brain MRI and whole spine MRI done 1 year after surgery showed neither residual nor recurrent tumor in the whole axis. She is regularly followed-up at our outpatient department and is doing well except having left vocal cord palsy, which occurred before surgery. CONCLUSION: Medulloblastoma, ependymoma, glioma, hemangioblastoma, and cavernous angioma are common intraaxial tumors in the medulla oblongata and fourth ventricle. Intracranial germ cell tumors originate from extragonadal seminal cells and have been found in 0.4-3.4% of patients with primary central nervous system (CNS) tumors in Western countries, while the incidence is reported to be 5-8 times greater in Japan and the Far East. Although germinoma of medulla oblongata is rare and difficult to diagnose preoperatively, it should be included in the differential diagnosis of medulla masses with fourth ventricle extension, especially in Asian population.

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