Yukihiro Wakabayashi

Up-regulation of Urokinase-type Plasminogen Activator and its Receptor Correlates with Enhanced Invasion Activity of Human Glioma Cells Mediated by Transforming Growth Factor-α or Basic Fibroblast Growth Factor

Glioblastoma multiforme is a highly malignant tumor that is extremely refractory to therapy. One reason is its highly invasive nature into brain tissue. Metalloproteinases and their inhibitors, plasminogen activators (PA) and their inhibitors and cathepsins are thought to be involved in invasion by tumor cells. In this study, we determined if the urokinase-type plasminogen activator (uPA) and/or the urokinase-type plasminogen activator receptor (uPAR) were responsible for the invasion activity of a human glioma cell line. We determined the invasion activity of a human glioma U251 cell line using an in vitro invasion assay system. A 2.4- to 5.8-fold increase in invasion activity was observed in the presence of basic fibroblast growth factor (bFGF) or transforming growth factor (TGF)-α. Northern blot analysis showed that bFCF and TGF-α treatment was associated with increases in cellular mRNA levels of uPA and uPAR. Zymographic activity correlated to mRNA levels of uPA and uPAR. Addition of an anti-uPAR monoclonal antibody significantly inhibited the invasion activity induced by bFGF- and TGF-α. Irsogladine, an inhibitor of uPA synthesis, also blocked the invasion activity. These observations suggest that uPA and its receptor have a role in the invasion process of human gliomas.

Sleep cycle in patients in a state of permanent unconsciousness

Since the recent diagnostic criteria for persistent vegetative state (PVS) require the presence of a sleep-wake cycle, certain patients in similar conditions should be excluded from PVS. Since the diagnosis of PVS might correlate with legal issues, an accurate definition is necessary. To clarify the clinical significance of a sleep-wake cycle, 12 patients in a state of permanent unconsciousness after brain damage were clinically and electrophysiologically reviewed. In addition to routine EEG, evoked potentials and MRI, the simultaneous recordings of EEG and patients by videotape were performed for 24 hours. Four patients who showed severe brain stem damage did not show a sleep-wake cycle. In the other eight patients, a sleep-wake cycle was observed. However, among these patients there was no obvious difference in their clinical status. Although these data suggest that the presence of a sleep-wake cycle might reflect the brain stem damage, it is considered that the presence of a sleep-wake cycle might be unnecessary for the diagnostic criteria for PVS. Further study of various forms of brain damage will provide better understanding of the significance of the presence of a sleep-wake cycle.

Dual Pathways to Tubular Morphogenesis of Vascular Endothelial Cells by Human Glioma Cells : Vascular Endothelial Growth Factor/Basic Fibroblast Growth Factor and Interleukin-8

In this study, we examined whether human glioma cells are angiogenic in a model using human microvascular endothelial cells, and also which factor is responsible for the glioma‐dependent angiogenesis. Tubular morphogenesis in type I collagen gel by human microvascular endothelial cells was stimulated in the presence of 10 and 100 ng/ml of vascular endothelial growth factor (VEGF), 10 ng/ml basic fihroblast growth factor (bFGF) and 10 ng/ml of interleukin‐8 (IL‐8). Tube formation of the microvascular endothelial cells was assayed in the glioma cell lines IN157 and IN301, co‐cultured using the double chamber method. IN301 cells had much higher levels of VEGF, bFGF and transforming growth factor‐(mRNA than IN157 cells, whereas the two had similar levels of transforming growth factor‐Alfa mRNA. By contrast, IN157 cells had much higher levels of IL‐8 mRNA than IN301 cells. IN301‐dependent tubular morphogenesis was inhibited by anti‐VEGF or anti‐bFGF antibody, and the inhibition was almost complete when anti‐VEGF and anti‐bFGF antibodies were present. On the other hand, IN157‐dependent tubular morphogenesis was inhibited by anti‐IL‐8 antibody, but not by anti‐VEGF or anti‐bFGF antibodies. These findings demonstrated dual paracrine controls of tumor angiogenesis by human glioma cells. One is mediated through VEGF and/or bFGF, and the other, through IL‐8.

Inhibition of tubular morphogenesis in human microvascular endothelial cells by co-culture with chondrocytes and involvement of transforming growth factor β: a model for avascularity in human cartilage

Tube formation in collagen gel was induced in human omental microvascular endothelial (HOME) cells in the presence of epidermal growth factor (EGF) or transforming growth factor-alpha (TGF-alpha). TGF-alpha enhanced the expression of the tissue type plasminogen activator (t-PA) gene, whereas TGF-beta increased the expression of the PA inhibitor-1 (PAI-1) gene and inhibited that of the t-PA gene. TGF-beta inhibited the tube formation of HOME cells in type I collagen gel that was enhanced in response to TGF-alpha. We have recently established an angiogenesis model in vitro in which vascular endothelial cells on type I collagen gel in an inner chamber are co-cultured with other types of cells in an outer chamber. Here we examined whether the EGF/TGF-alpha-induced tube formation in HOME cells was modulated by human chondrocytes co-culture in the outer chamber. TGF-alpha-dependent tube formation of HOME cells was inhibited when human chondrocytes were co-cultured in the outer chamber. This chondrocyte-induced inhibition of tube formation was partly abrogated by co-administration of anti-TGF-beta antibody. These findings suggest that TGF-beta is partly involved in the human chondrocyte-dependent inhibition of tube formation by human microvascular endothelial cells. This is the first model system demonstrating that avascularity of human chondrocytes is partly due to TGF-beta family produced from them.

The exogenous control of transfected c-fos gene expression and angiogenesis in cells implanted into the rat brain

Previously, we established a stable transfectant, Nf-1, from normal rat kidney (NRK) fibroblasts transfected with a human metallothionein II A (hMT-IIA) promoter/human genomic c-fos fusion gene to produce c-Fos protein. Since the hMT-IIA promoter can be activated by heavy metals, the level of human c-fos gene expression can be increased by addition of heavy metals to the culture medium of Nf-1 cells and the anchorage-independent growth of Nf-1 in soft agar is markedly enhanced in the presence of transforming growth factor-beta (TGF-beta) and epidermal growth factor (EGF). In this study, we found that the hMT-IIA promoter can be activated by zinc, resulting in the elevation of fused c-fos gene expression in Nf-1 cells. We transplanted NRK and Nf-1 cells into the striatum of the rat brain and investigated whether expression of the human c-fos gene could be modified in the brain by exogenous zinc. After 8 weeks, we found that the Nf-1 cells could survive in the rat brain without any immunosuppression and grafts of Nf-1 induced angiogenesis when zinc was administered. Such implants enhanced the expression of c-fos mRNA by zinc. These results indicated that the transplanted cells continued expressing the c-fos transgene when the rats were given drinking water containing zinc, resulting in the promotion of cell growth and of neovascularization. This study will present a useful animal model of gene therapy by control of transgene expression in the brain.

An adult case of cerebral malakoplakia successfully cured by treatment with antibiotics, bethanechol and ascorbic acid

Cerebral malakoplakia is a very rare chronic inflammatory disease. We herein report the case of a 49-year-old female who presented with a slowly progressive speech disturbance and right hemiparesis. Computed tomography and magnetic resonance imaging showed irregular enhanced mass lesions with numerous scattered areas of calcification in the left insula, thalamus and basal ganglia. Histopathologically, the biopsy specimen showed basophilic laminated inclusion bodies and intracellular and extracellular calculospherules, usually with a typical targetoid appearance (Michaelis-Gutmann bodies). Treatment with antibiotics, bethanechol and ascorbic acid improved her symptoms in association with a decrease in the abnormal calcification and enhancement. The cerebral malakoplakia mimicked a brain tumor in terms of the patients clinical course and neuroradiological image findings; however, it was successfully cured with medical treatment. This case provides evidence that the pathogenesis of cerebral malakoplakia is deeply tied to bacterial infection and that medical treatment is effective in cases of this disease.

Evidence of apoptotic procedure in deafferented striatum after cortical injury in young adult rats

In denervated striatum after excitotoxic cortical lesion in young adult rats, apoptotic cells, though quite few, were observed by TUNEL 2 weeks after surgery. Also, prominent expressions of p53 were observed at the same time. These data indicate that apoptotic procedure may be involved in the denervation-induced degeneration even in young adults.

Utility and Efficacy of a Rigid Endoscope for Recurrent Huge Chronic Subdural Hematoma: Case Report

An 83-year-old male patient was admitted to our hospital due to consciousness disturbance. Computed tomography demonstrated a huge chronic subdural hematoma on the left side. The thickness was 4 cm, and the cingulate gyrus was herniated to the right side. Blood examination showed that prothrombin time and activated partial thromboplastin time were normal. Bleeding time was slightly prolonged at 3 minutes 30 seconds. Emergency surgery was performed on admission. Three weeks after the first surgery, the patient became progressively drowsy and feeding was slow. Repeated computed tomographic scans demonstrated recurrence. At the second surgery, we used the 70-degree rigid endoscope (Storz, Germany) to obtain a direct view of the clot and bleeding site. We removed the clot and washed out the cavity with saline. Six months after the second surgery, there has not been any recurrence of the chronic subdural hematoma. In Japan, many aged patients with ischemic heart disease or cerebral infarction have been treated with anticoagulative agent and/or antithrombotic agent. We need to carefully monitor patients receiving antithrombotic therapy or anticoagulation therapy. Special training in the care of such patients is needed for support staff to prevent falls. For aged patients, minimally invasive surgery such as endoscope-assisted surgery may be effective for thick or intractable chronic subdural hematoma.

Malignant Glioma Occurring in the Damaged Brain After Craniotomy: Posttraumatic Brain Tumors: A Review

It is very rare for malignant gliomas to occur after aneurysmal surgery. However, we report 2 cases of malignant gliomas, which occurred after craniotomies. A 67-year-old man was admitted because of right facial palsy due to a left frontal tumor. Ten years previously, the patient suffered a subarachnoid hemorrhage due to a ruptured left A3 portion aneurysm. He had motor aphasia and right hemiplasia caused by an infarction of the left anterior and middle cerebral arterial area due to vasospasm. Magnetic resonance imaging now revealed an enhancing tumor protruding into the infarction area. The histologic diagnosis was glioblastoma multiforme. A 66-year-old woman was admitted because of symptomatic epilepsy due to a left frontal tumor. Fourteen years previously, the patient suffered from left occulomotor nerve paralysis due to a left unruptured internal carotid-posterior communicating artery aneurysm. Neck clipping was performed, and a postoperative hemorrhage in the left frontal lobe was observed. Magnetic resonance imaging now revealed an enhancing tumor in the same region. The pathologic diagnosis was anaplastic oligosatrocytoma. These tumors occurred in the injured brain, which occurs as a complication after a craniotomy. We discuss the pathology and probable factors predisposing patients to develop malignant gliomas in areas of brain trauma.

Stereotactic radiosurgery for aggressive papillary tumor of the temporal bone: case report

BACKGROUND Papillary tumors of the temporal bone are very rare neoplasms that show locally aggressive behavior though they have low-grade histologic features. The best treatment for these tumors is a radical resection. However, if the tumor is very large, local invasiveness and hypervascularity can prevent surgeons from achieving a complete resection. As an additional treatment for the residual tumor, it remains controversial whether radiation therapy has any role. CASE DESCRIPTION The authors describe a 53-year-old woman who suffered from left-sided tinnitus, hearing loss, and diplopia due to a large aggressive papillary tumor of the temporal bone. Radiosurgery was very effective for the tumor, which had regrown a few years after conventional radiation therapy and chemotherapy. CONCLUSIONS The authors conclude that radiosurgery should be considered as an option for the treatment of aggressive papillary tumor of the temporal bone.