• Journal of Korean Neurosurgical Society
• /
• v.48 no.5
• /
• pp.445-447
• /
• 2010

Pilomyxoid astrocytoma (PMA) is a newly recognized variant of a pilocytic astrocytoma. This report describes a case of a pilomyxoid astrocytoma that occurred in the opticohypothalamus. The patient was a 18-year-old girl who complained decreased visual acuity and visual field over a period of two years. Magnetic resonance imaging (MRI) showed an irregular lobulated tumor with heterogeneous enhancement at the suprasellar region involving the hypothalamus. The mass was partially removed via the subfrontal approach. Its pathology was confirmed to be PMA. Adjuvant chemotherapy with cisplatin and vincristine was started following tumor resection. After four cycles, the mass showed a partial response to the chemotherapy. Although long-term outcome is yet to be determined, the administration of combined cisplatin and vincristine treatment seems to be an effective regimen for a pilomyxoid astrocytoma.

• Interdisciplinary Bio Central
• /
• v.5 no.1
• /
• pp.1.1-1.8
• /
• 2013

High quality publicly-available transcriptomic data representing relationships in gene expression across a diverse set of biological conditions is used as a context network to explore transcriptomics of the CNS. The context network, 18367Hu-matrix, contains pairwise Pearson correlations for 22,215 human genes across18,637 human tissue samples1. To do this, we compute a network derived from biological samples from CNS cells and tissues, calculate clusters of co-expressed genes from this network, and compare the significance of these to clusters derived from the larger 18367Hu-matrix network. Sorting and visualization uses the publicly available software, MetaOmGraph (http://www.metnetdb.org/MetNet_MetaOm-Graph.htm). This identifies genes that characterize particular disease conditions. Specifically, differences in gene expression within and between two designations of glial cancer, astrocytoma and glioblastoma, are evaluated in the context of the broader network. Such gene groups, which we term outlier-networks, tease out abnormally expressed genes and the samples in which this expression occurs. This approach distinguishes 48 subnetworks of outlier genes associated with astrocytoma and glioblastoma. As a case study, we investigate the relationships among the genes of a small astrocytoma-only subnetwork. This astrocytoma-only subnetwork consists of SVEP1, IGF1, CHRNA3, and SPAG6. All of these genes are highly coexpressed in a single sample of anaplastic astrocytoma tumor (grade III) and a sample of juvenile pilocytic astrocytoma. Three of these genes are also associated with nicotine. This data lead us to formulate a testable hypothesis that this astrocytoma outlier-network provides a link between some gliomas/astrocytomas and nicotine.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.1
• /
• pp.68-70
• /
• 2010

We report a case of intracranial dissemination developing approximately 4 months after partial removal of a spinal cord anplastic astrocytoma in a 22-year-old male. He presented with paraplegia on initial admission at a local hospital. Spinal magnetic resonance (MR) images disclosed multiple intramedullary lesions at the T3-11. The tumor was partially removed. The final histologic diagnosis was anaplastic astrocytoma. Four months after the operation, he was admitted with the symptoms of headache and deterioration of consciousness. MR images showed enhanced lesions in the anterior horn of the left lateral ventricle, and septum pellucidum. He underwent computed tomography-guided stereotactic biopsy and histological appearance was consistent with anaplastic astrocytoma. The clinical course indicates that the tumor originated in the spinal cord and extended into the subarachnoid space, first the spinal canal and later intracranial.

• Journal of Korean Neurosurgical Society
• /
• v.45 no.6
• /
• pp.381-385
• /
• 2009

The first case of intracranial metastases of a cervical intramedullary low-grade astrocytoma without malignant transformation in adult is presented in this report. Seven years ago, a 45 year-old male patient underwent biopsy to confirm pathologic characteristics and received craniocervical radiation and chemotherapy for a grade II astrocytoma in the cervical spinal cord. Two years later, posterior fusion was necessary for progressive kyphosis in the cervical spine. He was well for approximately 7 years after the primary surgery. Two months ago, he presented with partial weakness and incoordination with gait difficulty. MRI Scan demonstrated multiple small lesions in the cerebellar vermis and left hemisphere. After suboccipital craniectomy and posterior cervical exposure, the small masses in the cerebellar vermis and hemispheres were excised to a large extent by guidance of an intraoperative navigation system. The tumor at the cervical and brain lesions was classified as an astrocytoma (WHO grade II). When a patient with low-grade astrocytoma in the spinal cord has new cranial symptoms after surgery, radiaton, and chemotherapy, the possibility of its metastasis should be suspected because it can spread to the intracranial cavity even without malignant transformation as shown in this case.

• Radiation Oncology Journal
• /
• v.10 no.2
• /
• pp.163-169
• /
• 1992

A retrospective analysis was performed on 53 patients with brain malignant astrocytoma and glioblastoma multiforme treated with surgical resection and postoperative radiotherapy in the period between January 1980 and June 1991. There were 13 patients with malignant astrocytoma, 40 patients with glioblastoma multiforme. Survival rates were analyzed according to histologic grade, age, performance status, extent of surgical resection, tumor location, symptom duration, total radiation dose and addition of chemo­therapy after radiation therapy. 5 year actuarial survival rate for malignant astrocytoma was $29.4\%$, for glioblastoma multiforme was $2.8\%$. Histologic grade, age, performance status, total radiation dose were statistitically significant prognostic factors.

• Journal of Yeungnam Medical Science
• /
• v.7 no.2
• /
• pp.167-172
• /
• 1990

Astrocytoma in the thalamus is not so frequent in incidence (1%). Moreover, bilateral thalamic tumor is rare. Certain tumors of the thalamus are considered resectable but most of thalamic tumors are thought to be untouchable. Bilateral thalamic astrocytoma with hydrocephalus was diagnosed by stereotactic biopsy and ventriculo-peritoneal shunt operation was done with result of improvement. We report a case of astrocytoma in the bilateral thalamus with literature review.

• Journal of Korean Neurosurgical Society
• /
• v.60 no.3
• /
• pp.375-379
• /
• 2017

Midbrain gliomas are relatively rare neoplasms with a generally benign prognosis, with dissemination or metastasis not previously reported. We describe here a woman, in whom magnetic resonance imaging scans showed hydrocephalus and a tegmental lesion in the upper aqueduct. Endoscopic third ventriculostomy and biopsy were performed; during surgery, a second small lesion was observed in the infundibular recess. Histologically, the two lesions had the characteristics of low grade astrocytoma, suggesting that the midbrain astrocytoma may have been disseminated via the cerebral spinal fluid to the infundibular recess. Postoperatively this patient received radiotherapy for nearly one month. Although patients with these tumors are not usually administered adjunctive therapy, radiation and, combined modality therapy, including surgery, radiotherapy, and chemotherapy, may be beneficial in patients with midbrain gliomas with dissemination.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.4
• /
• pp.485-490
• /
• 2000

Objective : To study the expression of apoptosis and bcl-2 in the astrocytic tumors. Patients and Methods : A total of thirty-eight astrocytomas(9 cases in low grade astrocytoma, 12 cases in anaplastic astrocytoma and 17 cases in glioblastoma) are included in this study. Immunohistochemical stain for bcl-2 using monoclonal antibody, in situ end labelling technique for apoptosis were used. Results : The malignant group(anaplastic astrocytoma and glioblastoma) showed significantly higher apoptosis positive index(PI) compared to the benign group(low grade astrocytoma)(1.35 vs 0.14). However apoptosis PI and bcl-2 PI were not significantly different among three groups. Correlation between apoptosis PI and bcl-2 PI was not statistically significant(p=0.58). Conclusion : This result suggest that apoptosis PI and bcl-2 PI are not related the degree of malignancy in astrocytic neoplasm, but apoptosis PI in malignant group was higher possibly due to greater DNA damage.

• Journal of Korean Neurosurgical Society
• /
• v.56 no.3
• /
• pp.261-264
• /
• 2014

We report perfusion weighted imaging (PWI) findings of nonenhanced anaplastic astrocytoma in a 30-year-old woman. Brain magnetic resonance imaging showed a nonenhanced brain tumor with mild peritumoral edema on the right medial frontal lobe and right genu of corpus callosum, suggesting a low-grade glioma. However, PWI showed increased relative cerebral blood volume, relative cerebral blood flow, and permeability of nonenhanced brain tumor compared with contralateral normal brain parenchyma, suggesting a high-grade glioma. After surgery, final histopathological analysis revealed World Health Organization grade III anaplastic astrocytoma. This case demonstrates the importance of PWI for preoperative evaluation of nonenhanced brain tumors.

• Biomedical Science Letters
• /
• v.12 no.3
• /
• pp.131-137
• /
• 2006

RGS is a negative regulator of G-protein signaling and can be identified by the presence of a conserved $120{sim}125$ amino acid motif, which is referred to as the RGS box. A number of RGSs are induced in response to a wide variety of stimuli. Increased levels of RGSs lead to significant decreases in GPCR responsiveness. To obtain further evidence of a role of RGS proteins in rat C6 astrocytoma cells, we first determined the expression profile of RGS-specific mRNA in C6 cells using reverse transcription-polymerase chain reaction (RT-PCR) with a poly dT18 primer and transcript-specific primers. We found that RGS2, RGS3, RGS6, RGS9, RGS10, RGS12, and RGS16 were differentially expressed in C6 astrocytoma cells. The highest expression rate was found for RGS3, followed by RGS16, RGS10 and RGS9, whereas the expression level for RGS2 was barely detectable. We next assessed whether forskolin regulated the expression of RGSs expressed in C6 astrocytoma cells. The present study found that forskolin dose-dependently stimulated the expression of RGS2 transcripts. This up-regulation of RGS2 gene was abrogated by H-89, potent and broad-spectrum protein kinase A (PKA) inhibitors. Actinomycin D completely inhibited the up-regulation of RGS2 gene induced by forskolin $(10{\mu}M)$, indicating that the regulation of RGS2 gene is controlled at the transcriptional level. In addition, forskolin did significantly activate transcriptional cAMP response element (CRE) in either HEK 293 cells or C6 cells and did not modulate the $NF-{\kappa}B$ and AP-l activity as measured by luciferase reporter gene assay. Finally, forskolin induced the expression of RGS2 mRNA in C6 astrocytoma cells, which depend on the PKA pathway and CRE transcriptional pathways.