Down-regulation of MDR1 by Ad-DKK3 via Akt/NFκB pathways augments the anti-tumor effect of temozolomide in glioblastoma cells and a murine xenograft model.

BACKGROUND: Glioblastoma multiforme (GBM) is the most malignant of brain tumors. Acquired drug resistance is a major obstacle for successful treatment. Earlier studies reported that expression of the multiple drug resistance gene (MDR1) is regulated by YB-1 or NFκB via the JNK/c-Jun or Akt pathway. Over-expression of the Dickkopf (DKK) family member DKK3 by an adenovirus vector carrying DKK3 (Ad-DKK3) exerted anti-tumor effects and led to the activation of the JNK/c-Jun pathway. We investigated whether Ad-DKK3 augments the anti-tumor effect of temozolomide (TMZ) via the regulation of MDR1. METHODS: GBM cells (U87MG and U251MG), primary TGB105 cells, and mice xenografted with U87MG cells were treated with Ad-DKK3 or TMZ alone or in combination. RESULTS: Ad-DKK3 augmentation of the anti-tumor effects of TMZ was associated with reduced MDR1 expression in both in vivo and in vitro studies. The survival of Ad-DKK3-treated U87MG cells was inhibited and the expression of MDR1 was reduced. This was associated with the inhibition of Akt/NFκB but not of YB-1 via the JNK/c-Jun- or Akt pathway. CONCLUSIONS: Our results suggest that Ad-DKK3 regulates the expression of MDR1 via Akt/NFκB pathways and that it augments the anti-tumor effects of TMZ in GBM cells.

Blocking COX-2 induces apoptosis and inhibits cell proliferation via the Akt/survivin- and Akt/ID3 pathway in low-grade-glioma.

Approximately half of surgically-treated patients with low-grade-glioma (LGG) suffer recurrence or metastasis. Currently there is no effective drug treatment. While the selective COX-2 inhibitor celecoxib showed anti-neoplastic activity against several malignant tumors, its effects against LGG remain to be elucidated. Ours is the first report that the expression level of COX-2 in brain tissue samples from patients with LGG and in LGG cell lines is higher than in the non-neoplastic region and in normal brain cells. We found that celecoxib attenuated LGG cell proliferation in a dose-dependent manner. It inhibited the generation of prostaglandin E2 and induced apoptosis and cell-cycle arrest. We also show that celecoxib hampered the activation of the Akt/survivin- and the Akt/ID3 pathway in LGGs. These findings suggest that celecoxib may have a promising therapeutic potential and that the early treatment of LGG patients with the drug may be beneficial.

Congenital craniopharyngioma treated by radical surgery: case report and review of the literature.

PURPOSE: Craniopharyngiomas are 5-10 % of all pediatric tumors, but are seldomly encountered in the perinatal period. Only seven instances of a truly antenatal diagnosis of a congenital craniopharyngioma that subsequently underwent radical surgery have been reported. We present the case of a patient who received the diagnosis of a suprasellar tumor during the prenatal period and received radical surgery. METHODS: We report a case of a neonatal craniopharyngioma treated surgically. RESULTS: The pregnancy progressed uneventfully until a routine ultrasound at 37 weeks of gestation showed a 15 × 15 mm high echoic mass in the center of the fetal head. Neonatal Gd-enhanced T1-weighted MRI at 5 days of life showed a homogenously enhanced mass (16×22×15 mm) in the sellar and suprasellar lesion. As the tumor showed rapid growth at the 3rd month of life, the patient underwent a surgical treatment and the mass was totally removed. Three years later, the physical and mental development of the patient was normal, and Gd-MRI studies showed no tumor recurrence. CONCLUSION: The present case is the eighth case of a truly antenatal diagnosis of a craniopharyngioma that underwent successful radical surgery. Craniopharyngioma is a benign tumor and thought to be a slow growing tumor in childhood. The results of radical surgery were very poor, and the mortality and morbidity rates were high in the previous reports due to the huge size of tumor at operation. The present case demonstrated the rapid growth in short interval of Gd-MRI. This is the first report of tumor kinetics of congenital craniopharyngioma with previous reports. The calculated tumor doubling time in our case was 37 days.

Improvement of Plasma Biomarkers after Switching Stroke Patients from Other Angiotensin II Type I Receptor Blockers to Olmesartan.

BACKGROUND: Managing hypertension is crucial for preventing stroke recurrence. Some stroke patients experience resistant hypertension. In our experimental stroke model, olmesartan increased the expression of angiotensin (Ang) II converting enzyme-2. We hypothesized that switching to olmesartan affects biomarkers and the blood pressure (BP) in stroke patients whose BP is insufficiently controlled by standard doses of Ang II type I receptor blockers (ARBs) other than olmesartan. METHODS: We recruited 25 patients to study our hypothesis. All had a history of stroke or silent cerebral infarction. We switched them to olmesartan (10-40 mg per day) for 12 weeks and determined their plasma level of Ang-(1-7), peroxiredoxin, oxidized low-density lipoprotein (oxLDL)/ß-2-glycoprotein I (ß2GPI) complex, adiponectin, high mobility group box 1 (HMGB1), and tumor necrosis factor-α (TNFα) and recorded their BP before and after olmesartan treatment. RESULTS: After switching the patients to olmesartan, their plasma level of Ang-(1-7) as a vasoprotective indicator and adiponectin regulating metabolic syndrome was increased, and peroxiredoxin and the oxLDL/ß2GPI complex indicating its antioxidative stress and its proatherogenicity were lower than their baseline. This suggests that olmesartan may be more effective than other ARBs to improve these conditions. Neither HMGB1 nor TNFα reflecting an inflammatory response was affected, suggesting that the anti-inflammatory effects of olmesartan are similar to those of other ARBs. The recommended BP (<140/90) was obtained in 10 of the 25 patients after switching to olmesartan. No adverse events occurred. CONCLUSIONS: Switching from other ARBs to olmesartan may be a promising therapeutic option in patients with resistant hypertension.

Atypical teratoid rhabdoid tumor in the cavernous sinus of a toddler presenting with oculomotor nerve palsy.

INTRODUCTION: Atypical teratoid rhabdoid tumor (ATRT) is a rare, highly malignant, and aggressive tumor of infancy. Although the prognosis of ATRT has been extremely poor, recently, the first prospective study for ATRT demonstrated improvement of prognosis. On the other hands, oculomotor nerve palsy is rare in children and the most frequent etiology is congenital. To our knowledge, only a few ATRT cases presenting with oculomotor nerve palsy have been reported, but ATRT originating from the cavernous sinus (CS) has not yet been reported. CASE REPORT: An 18-month-old girl with right oculomotor nerve palsy was admitted, and a small mass in the right CS was detected with brain MRI. Although she received steroid pulse therapy and antimicrobial therapy, the mass continued to enlarge. One month after admission, the mass was partially resected and diagnosed as ATRT. Multimodal therapy including anthracycline-based chemotherapy, intrathecal therapy, and cranial irradiation was performed. Twenty-nine months after resection, she was alive without tumor relapse, but the oculomotor nerve palsy persisted. CONCLUSION: This is the first reported case of ATRT located in the CS presenting with oculomotor nerve palsy. This case was successfully treated with partial removal of the tumor, a new chemotherapy regimen for ATRT and cranial X-ray irradiation.

Usefulness of Palliative Prognostic Index, Objective Prognostic Score, and Neutrophil-Lymphocyte Ratio/Albumin Ratio As Prognostic Indicators for Patients Without Cancer Receiving Home-Visit Palliative Care: A Pilot Study at a Community General Hospital.

Background: Although the palliative prognostic index (PPI), objective prognostic score (OPS), and neutrophil-lymphocyte ratio/albumin ratio (NLR/Alb) are well-known prognostic indicators for cancer patients, they do not provide clarity when it comes to predicting prognosis in patients without cancer who receive home-visit palliative care. Objective: The aim of this study was to determine whether PPI, OPS, and NLR/Alb can predict prognosis for patients without cancer who received home-visit palliative care. Design: This is a retrospective study. Setting/Subjects: We recruited 58 patients without cancer who received home-visit palliative care from Tokushima Prefectural Kaifu Hospital, Japan, and died at home or at the hospital within seven days of admission between January 2009 and March 2023. Measurements: The PPI, OPS, and NLR/Alb of the study patients were evaluated at regular intervals, and statistical analysis was performed on the relationship between these indices and the time to death. Results: Simple regression analysis showed that PPI, OPS, and NLR/Alb were negatively correlated with the period until death (p < 0.001). The survival curves of the groups classified according to PPI, OPS, and NLR/Alb were significantly stratified. The predictive capacities of PPI, OPS, and NLR/Alb for death within 21 days were as follows: PPI (area under the curve [AUC]: 0.71; sensitivity: 59%; specificity: 68%), OPS (AUC: 0.73; sensitivity: 88%; specificity: 47%), and NLR/Alb (AUC: 0.72; sensitivity: 72%; specificity: 73%). Conclusions: PPI, OPS, and NLR/Alb were useful in predicting the survival period and short-term prognosis within 21 days for patients without cancer who received home-visit palliative care.

[Differential diagnosis of and therapy for anaplastic astroblastoma: case report and review of the literature].

Astroblastomas are rare glial tumors. We report a case of 33-year-old woman with high-grade astroblastoma with hypervascularity. She had a one-month history of right visual disturbance and papillar edema. MRI revealed a lobulated mass with cysts and flow voids in the right superficial frontal lobe, a phenomenon described as "bubbly appearance". Right carotid angiography demonstrated marked tumor stain and early venous filling. MR spectroscopy showed an increase in myoinositol and the choline/creatine ratio, and decreased N-acetyl aspartate. The lipid and lactate level was not increased. The well-circumscribed tumor was totally resected. Histological examination showed perivascular pseudorosettes and hyalinization of blood vessels with high cellularity, anaplastic nuclear features, focal necrosis, mitosis, and endothelial proliferation. Immunohistochemically, glial fibrillary acidic protein and S-100 protein were intensely positive and the MIB-1 labeling index was high(20%)in the tumor cells. Based on these findings, a diagnosis of high-grade astroblastoma was made. The patient received postoperative radiotherapy and chemotherapy with temozolomide and suffered no relapse in the course of 3 years after surgery. Characteristically, astroblastomas manifest a "bubbly appearance" and a lobulated mass on MRI scans. As these tumors tend to be hypervascular, angiograms are useful for designing the operative strategy. However, their low-or high grade is difficult to ascertain preoperatively based on MRI-, MRS-, and DSA findings. The standard therapy for high-grade astroblastoma is total resection and postoperative radiation therapy. As the incidence of tumor recurrence is high, we recommend additional chemotherapy with TMZ.

Activation of signal transducer and activator of transcription-3 by a peroxisome proliferator-activated receptor gamma agonist contributes to neuroprotection in the peri-infarct region after ischemia in oophorectomized rats.

BACKGROUND AND PURPOSE: The role of the phosphorylated signal transducer and activator of transcription-3 (p-STAT3) after cerebral ischemia by the peroxisome proliferator-activated receptor γ (PPARγ) agonist pioglitazone (PGZ) remains controversial. Whether the increase in p-STAT3 by estrogen is mediated by the estrogen receptor α is also obscure. We examined the role of p-STAT3, PPARγ, and estrogen receptor α against ischemic brain damage after PGZ treatment. METHODS: Female Wistar rats subjected or not subjected to bilateral oophorectomy were injected with 1.0 or 2.5 mg/kg PGZ 2 days, 1 day, and 1 hour before 90-minute middle cerebral artery occlusion-reperfusion and compared with vehicle-control rats. RESULTS: The cortical infarct size was larger in ovariectomized than in nonovarietomized rats; it was reduced by PGZ treatment. Inversely with the reduction of the infarct size, PPARγ, and p-STAT3 but not estrogen receptor α in the peri-infarct area were increased in PGZ-treated compared with vehicle-control rats. The increase in PPARγ and p-STAT3 was associated with the transactivation of antiapoptotic and survival genes and the reduction of caspase-3 in this area. Inhibitors of PPARγ or STAT3 abolished the PGZ-induced neuroprotection and the increase in p-STAT3. More importantly, p-STAT3 increased by PGZ was bound to PPARγ and the complex translocated to the nucleus to dock to the response element through p-STAT3. CONCLUSIONS: Our findings suggest that the activation in the peri-infarct region of p-STAT3 and PPARγ by PGZ is essential for neuroprotection after ischemia and that PGZ may be of benefit even in postmenopausal stroke patients.

Pathologic diversity of glioneuronal tumor with neuropil-like islands: a histological and immunohistochemical study with a special reference to isocitrate dehydrogenase 1 (IDH1) in 5 cases.

Glioneuronal tumor with neuropil-like islands (GTNI) is featured by "neuropil-like islands (NIs)" within dominating astroglial components. Isocitrate dehydrogenase (IDH) mutations, particularly IDH1 R132H (G395A), are found in WHO Grade II and III diffuse gliomas as well as secondary, but not primary, glioblastomas. We reviewed 5 cases of GTNI, and assessed histology and immunohistochemistry with various antibodies, including those for IDH1 R132H, as well as direct DNA sequencing for IDH1 G395A. NIs were variable in morphology, and constantly synaptophysin-positive and glial fibrillary acidic protein-negative. The glioma components were primary glioblastoma in 2 cases, anaplastic astrocytoma in 1 and anaplastic oligoastrocytoma in 2. The IDH1 R132H was expressed in the 2 cases with oligoastrocytoma: In 1, NIs and the astrocytoma-like area as well as the oligodendroglioma-like area were positive. In the other, only the oligodendrogliomalike area was positive. The mutation analysis performed on the latter case with DNA separately sampled from the oligodendroglioma- like area and the astrocytoma-like area detected IDH1 G395A in both areas. We have shown diverse pathologic aspects of GTNI. Also, we have shown that the expression of IDH1 R132H in GTNI is largely concordant with that in diffuse gliomas, and that it can be dependent on each histologic component although the mutant IDH1 gene is ubiquitously present within the tumor.

Statins promote the growth of experimentally induced cerebral aneurysms in estrogen-deficient rats.

BACKGROUND AND PURPOSE: The pathogenesis of cerebral aneurysms is linked to inflammation, degradation of the extracellular matrix, and vascular wall apoptosis. Statins exert pleiotropic effects on the vasculature, independent of their cholesterol-lowering properties. To explore the detailed pathogenesis of cerebral aneurysms, we examined their progression in a rat model and studied whether statins prevent their initiation and growth. METHODS: Cerebral aneurysms were induced in female rats subjected to hypertension, increased hemodynamic stress, and estrogen deficiency. The development of aneurysm was assessed morphologically on corrosion casts. The effects of pravastatin (5, 25, or 50 mg/kg per day) and of simvastatin (5 mg/kg per day) on their aneurysms were studied. Human brain endothelial cells were also used to determine the effects of pravastatin. RESULTS: Pravastatin (5 mg/kg per day) reduced endothelial damage and inhibited aneurysm formation; there was an association with increased endothelial nitric oxide synthase (eNOS) levels and a decrease in human brain endothelial cell adhesion molecules. Unexpectedly, 25 mg/kg per day and 50 mg/kg per day pravastatin and 5 mg/kg per day simvastatin promoted aneurysmal growth, and high-dose pravastatin induced aneurysmal rupture. The deleterious effects exerted by these statins were associated with an increase in apoptotic caspase-3 levels and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells, suggesting that statins exert bidirectional effects. CONCLUSIONS: Our results provide the first evidence that cerebral aneurysm growth is partly associated with apoptosis and issue a warning that statins exert bidirectional effects on cerebral aneurysms. Additional intensive research is necessary to understand better their mechanisms and to identify patients in whom the administration of statins may elicit deleterious effects.

Promyelocytic leukemia protein induces apoptosis due to caspase-8 activation via the repression of NFkappaB activation in glioblastoma.

Promyelocytic leukemia (PML) protein plays an essential role in the induction of apoptosis; its expression is reduced in various cancers. As the functional roles of PML in glioblastoma multiforme (GBM) have not been clarified, we assessed the expression of PML protein in GBM tissues and explored the mechanisms of PML-regulated cell death in GBM cells. We examined the PML mRNA level and the expression of PML protein in surgical GBM specimens. PML-regulated apoptotic mechanisms in GBM cells transfected with plasmids expressing the PML gene were examined. The protein expression of PML was significantly lower in GBM than in non-neoplastic tissues; approximately 10% of GBM tissues were PML-null. The PML mRNA levels were similar in both tissue types. The overexpression of PML activated caspase-8 and induced apoptosis in GBM cells. In these cells, PML decreased the expression of transactivated forms of NFkappaB/p65, and c-FLIP gene expression was suppressed. Therefore, PML-induced apoptosis resulted from the suppression of the transcriptional activity of NFkappaB/p65. PML overexpression decreased phosphorylated IkappaBalpha and nuclear NFkappaB/p65 and increased the expression of the suppressor of cytokine signaling (SOCS-1). A proteasome inhibitor blocked the reduction of activated p65 by PML. The reduction of PML is associated with the pathogenesis of GBM. PML induces caspase-8-dependent apoptosis via the repression of NFkappaB activation by which PML facilitates the proteasomal degradation of activated p65 and the sequestration of p65 with IkappaBalpha in the cytoplasm. This novel mechanism of PML-regulated apoptosis may represent a therapeutic target for GBM.

Boron neutron capture therapy for newly diagnosed glioblastoma.

PURPOSE: The efficacy, safety, and dose distribution of neutron capture therapy (NCT) were evaluated in 15 patients with newly diagnosed glioblastoma. METHODS AND MATERIALS: Seven patients received intraoperative NCT (protocol-1) and eight patients received external beam NCT (protocol-2). Sulfhydryl borane (5 g/body) was administered intravenously. Additionally, p-dihydroxyboryl-phenylalanine (250 mg/kg) was given in protocol-2. The external beam NCT was combined with fractionated photon irradiation. RESULTS: Four of 15 patients were alive at analysis for a mean follow-up time from diagnosis of 23.0M. Twelve of the 15 patients were followed up for more than one year, and 10 (83.3%) of the 12 patients maintained their Karnofsky Performance Status (KPS; 90 in eight patients and 100 in two patients) at 12 months. The median overall survival and the time to tumor progression (TTP) for all patients were 25.7 and 11.9 M, respectively. There was no difference in TTP between the protocol-1 (12.0 M) and protocol-2 (11.9 M). The 1- and 2-year survival rates were 80.0% and 53.3%, respectively. Three protocol-1 patients and one protocol-2 patient suffered transient orbital swelling accompanied by double vision (Grade 2); one of the three protocol-1 patients suffered post-epileptic brain swelling (Grade 4) requiring surgical intervention. CONCLUSION: It is suggested that NCT is effective for survival of newly diagnosed glioblastoma with acceptable adverse effects. Because of the limitation of the present NCT pilot study without the contemporary control arm, it is unconvincing whether the neutron capture reaction led to distinct survival benefits, and further optimized studies on less invasive external beam NCT in large series of patients are warranted.

Primary anaplastic pleomorphic xanthoastrocytoma with widespread neuroaxis dissemination at diagnosis--a pediatric case report and review of the literature.

We report a 5 year-old boy with primary anaplastic pleomorphic xanthoastrocytoma (PXA) with whole neuroaxis dissemination at diagnosis who experienced the sudden onset of generalized convulsion. Head- and spinal magnetic resonance imaging (MRI) showed widespread gadolinium (Gd)-enhanced lesions extending to the bilateral frontal- and medial temporal lobes and the spinal cord. Subsequent MRI study demonstrated that the lesion size increased without any neurological deterioration. Under a histopathologic diagnosis of anaplastic PXA he underwent adjuvant chemotherapy consisting of 12 cycles of carboplatin and vincristine. The patient is alive without any neurological deficits; follow-up MRI showed that the lesions remained stable during 18 months of chemotherapy. We report a very rare pediatric case of primary anaplastic PXA with dissemination involving the entire neuroaxis at the time of diagnosis.

REIC/Dkk-3 induces cell death in human malignant glioma.

The progression of glioma to more malignant phenotypes results from the stepwise accumulation of genetic alterations and the consequent disruption of the apoptotic pathway and augmentation of survival signaling. REIC/Dkk-3, a member of the human Dickkopf (Dkk) family, plays a role as a suppressor of the growth of several human cancers; however, to date it has not been identified in brain tumors. We compared the gene and protein expression of REIC/Dkk-3 in human malignant glioma and normal brain tissues using quantitative real-time PCR, Western blotting, and immunohistochemistry. We also performed small interfering REIC/Dkk-3 (siREIC/Dkk-3) knockdown and REIC/Dkk-3 overexpression experiments to examine the role of REIC/Dkk-3 in human malignant glioma cells in vitro. In brain tissue from patients with malignant glioma, the gene and protein expression of REIC/Dkk-3 was lower than in normal brain tissue and was related to the malignancy grade. In the primary glioblastoma cell line, REIC/Dkk-3 transfection led to apoptosis owing to the activation of phosphorylated JUN, caspase-9, and caspase-3 and the reduction of beta-catenin; in REIC/Dkk-3 knockdown experiments, cell growth was augmented. Our results suggest that REIC/Dkk-3 regulates the growth and survival of these cells in a caspase-dependent and -independent way via modification of the Wnt signaling pathway. Our work is the first documentation that the gene and protein expression of REIC/Dkk-3 is down-regulated in human malignant glioma. Our demonstration of the mechanisms underlying REIC/Dkk-3-induced cell death indicates that REIC/Dkk-3 plays a pivotal role in the biology of human malignant glioma and suggests that REIC/Dkk-3 is a promising candidate for molecular target therapy.

Diagnostic Performance of Arterial Spin Labeling for Grading Nonenhancing Astrocytic Tumors.

PURPOSE: We evaluated the utility of arterial spin labeling (ASL) imaging of tumor blood flow (TBF) for grading non-enhancing astrocytic tumors. MATERIALS AND METHODS: Thirteen non-enhancing astrocytomas were divided into high-grade (n = 7) and low-grade (n = 6) groups. Both ASL and conventional sequences were acquired using the same magnetic resonance machine. Intratumoral absolute maximum TBF (TBFmax), absolute mean TBF (TBFmean), and corresponding values normalized to cerebral blood flow (TBFmax and TBFmean ratios) were measured. The Mann-Whitney U test and receiver operating characteristic (ROC) curve analysis were used to assess the accuracy of TBF variables for tumor grading. RESULTS: Compared with low-grade astrocytoma, high-grade astrocytoma exhibited significantly greater absolute TBFmax (90.93 ± 24.96 vs 46.94 ± 20.97 ml/100 g/min, P < 0.001), TBFmean (58.75 ± 19.89 vs 31.16 ± 17.63 ml/100 g/min, P < 0.001), TBFmax ratio (3.34 ± 1.22 vs 1.35 ± 0.5, P < 0.001), and TBFmean ratio (2.15 ± 0.94 vs 0.88 ± 0.41, P < 0.001). The TBFmax ratio yielded the highest diagnostic accuracy (sensitivity 100%, specificity 86.3%), while absolute TBFmean yielded the lowest accuracy (sensitivity 85.7%, specificity 70.1%) by ROC analysis. CONCLUSION: Parameters from ASL perfusion imaging, particularly TBFmax ratio, may be useful for distinguishing high-grade from low-grade astrocytoma in cases with equivocal conventional MRI findings.

Postoperative Hematoma Requiring Recraniotomy in 1149 Consecutive Patients With Intracranial Tumors.

BACKGROUND: The reported 30-day mortality rate after brain tumor surgery is 2.2% to 2.9%, with a postoperative hematoma (POH) as the most frequent cause of death. OBJECTIVE: To investigate the risk factors for a POH requiring a recraniotomy after brain tumor surgery in a large, contemporary, single-institution consecutive series. METHODS: We included 1149 patients who underwent surgery for intracranial tumors at the Tokushima University Hospital from 1997 to 2014. The patient charts were retrospectively studied from our prospectively collected database. We analyzed the risk factors, type of hemorrhage, time to reoperation, and outcomes. RESULTS: The incidence of a POH requiring a recraniotomy was 2.09%. Among the patients with a POH requiring a recraniotomy, 12.5% died within 30 days of the first surgery. The incidence of a POH requiring a recraniotomy significantly correlated with the incidence of a hemangioblastoma, infratentorial tumors, and a prolonged operative time (>10 h), but not with the patient age or sex, surgical procedure (biopsy or craniotomy), surgical type (primary or secondary), bleeding volume, or intraoperative blood transfusion requirement. A recraniotomy for a POH was performed in 54% of the patients just after the first operation, and within 24 h for 79% of the patients. The clinical status at the time of discharge deteriorated in 52% of the patients. CONCLUSION: Hemangioblastomas, infratentorial tumors, and an operative time exceeding 10 h were significantly correlated with an increased risk of a POH; these factors were responsible for 12.5% of the 30-day surgical mortality rate.

Differences In High-Intensity Signal Volume Between Arterial Spin Labeling And Contrast-Enhanced T1-Weighted Imaging May Be Useful For Differentiating Glioblastoma From Brain Metastasis.

PURPOSE: To determine whether differences in tumor volume between arterial spin labeling (ASL) and contrast-enhanced T1-weighted MR images (CE+T1WI) can help differentiate glioblastoma (GBM) from brain metastasis. MATERIALS AND METHODS: Patients with a diagnosis of GBM (n=25) or brain metastasis (n=13) were examined by both conventional and ASL MR imaging. Volumes of interest with high signal intensity on ASL and CE+T1WI were defined using three dimensional analysis software. Tumor volume difference (ASL-CE) and tumor volume ratio (ASL/CE) were obtained. Absolute maximal tumor blood flow (TBF) and TBF ratio (normalized to white matter) were also measured. The Mann-Whitney U test and receiver operating characteristic curve analysis were performed to compare measurements between the tumor groups. RESULTS: Both tumor volume difference and tumor volume ratio were significantly higher in GBM than in metastasis. Both TBF and TBF ratio were higher for GBM than for metastasis, but the differences were not significant. CONCLUSION: The difference in tumor volume as measured by ASL high signal intensity and CE+T1WI might be useful for differentiating GBM from metastasis, whereas ASL-derived TBF is insufficient. J. Med. Invest. 64: 58-63, February, 2017.

Characteristics of medical students who would like to be a generalist physician and contribute to remote area medicine.

We administered a questionnaire to 5th grade medical students to examine the effect of community-based clinical practice on their attitudes to remote area medicine and their course after the graduation. Data from 192 students were obtained. The intensity of students' attitudes was estimated by using visual analogue scale. The intensities of the interest and a sense of fulfillment in remote area medicine were significantly increased after the practice. A significantly lower level of the intensity to become a generalist than that to become a specialist was seen in the students with low intensity in a sense of fulfillment. The percentages of the students who answered that they can work for 5 years or more in remote area were significantly lower in students with low intensity of a sense of fulfillment than in those with high intensity. A significantly higher percentage in students who worked at a familiar prefecture to them after the graduation was seen in female than in male. This study shows that the community-based practice is meaningful in increasing motivation which desire to work in remote area medicine, and that the motivation may affect their course after the graduation. J. Med. Invest. 64: 210-216, August, 2017.

Design and Synthesis of Novel Anti-metastatic Hypoxic Cytotoxin TX-2137 Targeting AKT Kinase.

BACKGROUND: The hypoxic microenvironment plays a crucial role in the malignant progression of tumor cells. Moreover, AKT, a serine/threonine kinase, is activated by various extracellular growth factors and is important for cell growth, survival, and motility of leukocytes, fibroblasts, endothelial cells, and tumor cells. Therefore, we aimed to design an anti-metastatic hypoxic cytotoxin which has inhibitory effects on AKT. RESULTS: TX-2137 was designed and synthesized based on the structural similarity of a preexisting AKT1/2 kinase inhibitor and a hypoxic cytotoxin tirapazamine. TX-2137 effectively reduced the expression of phosphorylated AKT and matrix metalloproteinase 9 (MMP9) and showed strong inhibition of the proliferation of B16-F10, HT-1080, and MKN-45 cells. In addition, TX-2137 exhibited hypoxia-selective cytotoxicity towards A549 cells and inhibited liver metastasis of B16-F10 cells in a xenograft chick embryo model in the same way as doxorubicin. CONCLUSION: TX-2137 may be a potent lead compound in the development of a novel anti-metastatic AKT kinase inhibitor.

Boron neutron capture therapy using mixed epithermal and thermal neutron beams in patients with malignant glioma-correlation between radiation dose and radiation injury and clinical outcome.

PURPOSE: To clarify the correlation between the radiation dose and clinical outcome of sodium borocaptate-based intraoperative boron neutron capture therapy in patients with malignant glioma. METHODS AND MATERIALS: The first protocol (P1998, n = 8) prescribed a maximal gross tumor volume (GTV) dose of 15 Gy. In 2001, a dose-escalated protocol was introduced (P2001, n = 11), which prescribed a maximal vascular volume dose of 15 Gy or, alternatively, a clinical target volume (CTV) dose of 18 Gy. RESULTS: The GTV and CTV doses in P2001 were 1.1-1.3 times greater than those in P1998. The maximal vascular volume dose of those with acute radiation injury was 15.8 Gy. The mean GTV and CTV dose in long-term survivors with glioblastoma was 26.4 and 16.5 Gy, respectively. A statistically significant correlation between the GTV dose and median survival time was found. In the 11 glioblastoma patients in P2001, the median survival time was 19.5 months and 1- and 2-year survival rate was 60.6% and 37.9%, respectively. CONCLUSION: Dose escalation contributed to the improvement in clinical outcome. To avoid radiation injury, the maximal vascular volume dose should be <12 Gy. For long-term survival in patients with glioblastoma after boron neutron capture therapy, the optimal mean dose of the GTV and CTV was 26 and 16 Gy, respectively.