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Hironori Fujisawa

Publications and source records attributed to Hironori Fujisawa.

18 recordsLinked to original sources

Identification of biomarkers from mass spectrometry data using a "common" peak approach.

BACKGROUND: Proteomic data obtained from mass spectrometry have attracted great interest for the detection of early-stage cancer. However, as mass spectrometry data are high-dimensional, identification of biomarkers is a key problem. RESULTS: This paper proposes the use of "common" peaks in data as biomarkers. Analysis is conducted as follows: data preprocessing, identification of biomarkers, and application of AdaBoost to construct a classification function. Informative "common" peaks are selected by AdaBoost. AsymBoost is also examined to balance false negatives and false positives. The effectiveness of the approach is demonstrated using an ovarian cancer dataset. CONCLUSION: Continuous covariates and discrete covariates can be used in the present approach. The difference between the result for the continuous covariates and that for the discrete covariates was investigated in detail. In the example considered here, both covariates provide a good prediction, but it seems that they provide different kinds of information. We can obtain more information on the structure of the data by integrating both results.

Algorithms↗

C-kit gene mutation: common and widely distributed in intracranial germinomas.

OBJECT: Of the intracranial germ cell tumors (IGCTs), 10% of germinomas and most nongerminomatous tumors remain refractory to multimodality therapy. The authors investigated the mutation of c-kit and the expression of its product KIT in IGCTs to identify tumors susceptible to imatinib mesylate, a synthetic agent targeting KIT. METHODS: The authors investigated 26 IGCTs, including 13 germinomas, five mixed germ cell tumors (MGCTs), four immature teratomas (ITs), and two each of yolk sac tumors and choriocarcinomas. These tumors were examined for the expression of KIT and CD34 by immunohistochemical analysis, and for mutations in exons 2, 8 to 11, 13, and 17 of c-kit. Strong KIT expression was found in the cell membrane of germinomas (100%) and germinomatous cells of MGCTs (80%), as well as in the cytoplasm of epithelial and smooth-muscle cells of ITs. The membranous expression of CD34 was found in the nongerminomatous tumor cells and the chondrocytes of MGCTs (60%), ITs (100%), and a choriocarcinoma (50%), but not in germinomas and germinomatous cells. A total of five missense mutations distributed in exons 2, 11, 13, and 17 of c-kit were detected in three (23%) of the 13 germinomas. The novel mutations E73K, T96M (both in exon 2), and A636V (in exon 13) were detected in a single tumor. The presence or type of c-kit mutation was not correlated with patient prognosis. CONCLUSIONS: Immunohistochemical analysis of KIT expression is useful for the diagnosis of germinoma. This study may help in clarifying the pathogenesis of IGCTs and in identifying tumors susceptible to drugs targeting KIT.

Adolescent↗

Genotypes at chromosome 22q12-13 are associated with HIV-1-exposed but uninfected status in Italians.

OBJECTIVE: Despite multiple and repeated exposures to HIV-1, some individuals possess no detectable HIV genome and show T-cell memory responses to the viral antigens. HIV-1-reactive mucosal IgA detected in such uninfected individuals suggests their possible immune resistance against HIV. We tested if the above HIV-1-exposed but uninfected status was associated with genetic markers other than a homozygous deletion of the CCR5 gene. METHODS: Based on our mapping in chromosome 15 of a gene controlling the production of neutralizing antibodies in a mouse retrovirus infection, we genotyped 42 HIV-1-exposed but uninfected Italians at polymorphic loci in the syntenic segment of human chromosome 22, and compared them with 49 HIV-1-infected and 47 uninfected healthy control individuals by a closed testing procedure. RESULTS: A significant association was found between chromosome 22q12-13 genotypes and a putative dominant locus conferring anti-HIV-1 immune responses in the exposed but uninfected individuals. Distributions of linkage disequilibrium across chromosome 22 also differed between the exposed but uninfected and two other phenotypic groups. CONCLUSIONS: The data indicated the presence of a new genetic factor associated with the HIV-1-exposed but uninfected status.

Animals↗

Cluster analysis and association study of structured multilocus genotype data.

We propose an algorithm for testing association using structured multilocus genotype data. The algorithm implements the clustering of the data by a hierarchical clustering technique and a k-means algorithm. After clustering, the program analyzes all the clusters together using the Mantel-Haenszel (MH) test, by which common associations in the clusters are examined. To use the MH test, the number of subpopulations has to be determined. A method of cross-validation (CV) and the k-means algorithm are applied for estimating the number of subpopulations. The algorithm described was implemented in the computer program POPSTRUCT. In the simulation study, we found that when the two groups with different marker allele frequencies were combined, an inflation of the type I errors was observed. The inflation was more marked when the differences in the marker allele frequencies were larger, the difference in the minor allele frequencies at the disease locus was larger, and the genotype relative risk associated with the disease locus was higher. Our simulation study indicated that the MH test was efficient for decreasing type I errors and increasing the power compared with any test performed on each cluster. Then, we compared the results of STRUCTURE, a model-based method, and POPSTRUCT, a distance-based method. When two subgroups with different allele frequencies were mixed together at a high fixed ratio, POPSTRUCT was superior to STRUCTURE in classifying the combined population into the accurate clusters, each of which reflects one of the original groups.

Algorithms↗

Cyclin D1 is overexpressed in atypical teratoid/rhabdoid tumor with hSNF5/INI1 gene inactivation.

OBJECT: Although atypical teratoid/rhabdoid tumor (AT/RT) is known to generate through inactivation of the hSNF5/INI1 gene on chromosome 22q, the downstream molecular mechanism remains unclear. We histologically and molecularly reviewed our pediatric brain tumors for unrecognized AT/RTs and evaluated the role of cyclin D1, a potential molecular target of hSNF5/INI1. METHODS: We analyzed 16 tumors under three years of age: seven medulloblastomas, three anaplastic ependymomas (E IIIs), two each of supratentorial primitive neuroectodermal tumors (sPNETs) and choroid plexus carcinomas (CPCs), and one each of neuroblastoma and pineoblastoma. Immunohistochemistry for glial fibrillary acidic protein, vimentin, epithelial membrane antigen, smooth muscle actin and cyclin D1 was performed. Polymerase chain reaction (PCR)-single-strand conformation polymorphism analysis with direct sequencing, differential PCR and microsatellite analysis were conducted for hSNF5/INI1mutation, homozygous deletion and loss of heterozygosity (LOH) on 22q, respectively. Because of the presence of rhabdoid cells and the polyimmunophenotypic features, the diagnosis was revised to AT/RT in five (31%) tumors, namely, two E IIIs and one each of medulloblastoma, CPC and pineoblastoma. Three of them harbored such hSNF5/INI1 aberrations as germline single base deletion (492/6 delC) and missense mutation (C157T) together with LOH 22q or homozygous deletion. Cyclin D1 was overexpressed in those three tumors but not in the two that lacked hSNF5/INI1 inactivation. CONCLUSION: AT/RT can be misdiagnosed as a variety of tumors, including ependymoma that potentially harbors LOH 22q. Our data indicate that cyclin D1 is a target of hSNF5/INI1in primary tumors.

Central Nervous System Neoplasms↗

CT arteriography for orbital tumors: diagnostic and surgical value.

The aim of this study is to investigate the efficacy of dynamic computed tomography (CT) during selective angiography (CT-arteriography) of orbital tumors in the evaluation of intratumoral vascular anatomy, feeding artery territory, and histological diagnosis. Among 35 consecutive cases with various orbital lesions, those cases showing tumor staining or pooling of the contrast medium on digital subtraction angiography (DSA) were evaluated by CT-arteriography (n = 14). The information obtained by CT-arteriography was compared with that provided by enhanced MRI (n = 31) and dynamic MRI (n = 21), in which the contrast medium was injected intravenously. In addition to the visualization of fine vascular anatomy, CT-arteriography emphasized areas of nodular enhancement and non-enhancing cystic/necrotic components as well as the intratumoral feeding arteries. Patterns of CT-arteriography were categorized into three subgroups: homogeneous enhancement (benign lymphoid lesion), partial enhancement (schwannomas and carcinomas), and patchy multinodular enhancement (specific for cavernous angiomas). In addition, CT-arteriography with selective arterial catheterization clearly delineated the feeding artery territories. CT-arteriography, with a minimal dose of contrast medium, can offer significant advantages over intravenously injected dynamic neuroimaging, and provides additional valuable preoperative information about the orbital tumor under investigation.

Adult↗

Correlation of gamma-catenin expression with good prognosis in medulloblastomas.

OBJECT: Medulloblastoma is a malignant cerebellar tumor of childhood and is difficult to cure due to frequent cerebrospinal fluid dissemination. Amplification of the c-myc gene (4%) and messenger (mRNA) overexpression (50%) are known to be adverse prognostic indicators. Because mRNA overexpression cannot be explained by gene amplification alone, mechanisms other than gene amplification are postulated. Molecules on the Wnt signal pathway in primary tumors were examined. METHODS: Immunohistochemical and cytogenetic examinations of beta- and gamma-catenin, c-myc, N-myc, and cyclin D1 in 24 primary medulloblastomas were conducted, and their clinical relevance was evaluated. Cytoplasmic/membranous staining of beta- and gamma-catenin was detected in 19 (79%) and nine (37%) cases, respectively, and nuclear expression of cyclin D1 and c-myc was detected in six (25%) and 21 (83%) cases, respectively. The expression levels of gamma-catenin in Western blot analysis and immunohistochemistry were similar. By differential polymerase chain reaction, c-myc and N-myc were amplified separately in two large cell/anaplastic medulloblastomas. No cyclin D1 amplification, or beta- or gamma-catenin mutations were found. Kaplan-Meier analysis revealed no dissemination at diagnosis (Chang Grade M0) and gamma-catenin expression was correlated with good prognosis (p = 0.0002 and 0.003, respectively). Expression of gamma-catenin was also significant in the M0 group (p = 0.022). Expression of cyclin D1 showed a trend toward adverse outcome (p = 0.057) and all patients in whom cyclin D1 expression was found died of disease. CONCLUSIONS: Expression of gamma-catenin is of great prognostic value and its immunohistochemistry may be useful for further stratification of treatment. Cyclin D expression may have the potential to be an adverse prognostic indicator.

Adolescent↗

[Successful treatment of Cushing disease with the sphenoid sinus of conchal type: usefulness of inferior petrosal sinus sampling and STEALTH navigation system: a case report].

We report a case of Cushing disease whose microadenoma was not identified by MRI with dynamic study and whose sphenoid sinus was conchal in type. Venous sampling test in the bilateral inferior petrosal sinus demonstrated ACTH hypersecretion on the right side. The patient underwent transsphenoidal surgery. A poorly pneumatized sphenoid sinus was drilled effectively, guided by the STEALTH navigation system. After the first operation, the patient's serum ACTH concentration was still high, suggesting that tumor removal was incomplete. Then she underwent the second operation and the residual tumor was completely removed with the assistance of the STEALTH navigation system again. Postoperatively, her serum ACTH concentration dropped below 5 pg/ml. In this case, inferior petrosal sinus sampling was extremely helpful for the diagnosis of Cushing disease, and operations were able to be performed safely using the neuronavigation system in drilling of the incompletely pneumatized sphenoid sinus.

Adenoma↗

Autologous amnion graft for repair of myelomeningocele: technical note and clinical implication.

OBJECTIVE AND IMPORTANCE: Amniotic membrane can be used as autologous reconstruction graft material when aseptically obtained. We introduce here a novel repair technique using autologous amnion graft, and report a case presentation of myelomeningocele successfully treated with this graft material. TECHNIQUE: Amniotic membrane, which was composed of amnion and chorion, was aseptically harvested at cesarean section. Removing chorionic tissue, amnion containing monolayer of amniotic epithelial cells and underlining fibrous tissue was isolated. After the procedure of reconstruction of neural and meningeal elements, the membrane was placed as onlay autograft over the reconstructed neural structure followed by suture of undermined skin flap without any myocutaneous flap transfer technique or fascial transposition from paraspinal muscles. RESULTS: The postoperative healing process of the wound was excellent. CONCLUSION: Autograft of amniotic tissue has no risks of rejection, foreign body reaction, or transmission of slow virus infection to reconstruct the lesion of newborn patient. Amnion autograft would be a biologic rationale to promote wound healing, being applied as a part of a variety of pediatric neurosurgical procedure.

Adult↗

Recurrent intracranial solitary fibrous tumor with cerebrospinal fluid dissemination. Case report.

Solitary fibrous tumor (SFT) is a benign and rare neoplasm. To date, only 37 patients with intracranial SFTs have been reported. Although a number of the tumors were recurrent and some later underwent malignant transformation, none of these lesions progressed to cerebrospinal fluid (CSF) dissemination. In this paper the authors report a case of SFT in which the lesion recurred several times and ultimately was disseminated by the CSF. The patient was a 63-year-old woman with multiple intracranial and spinal tumors. Fifteen years before this presentation, at the age of 48 she had been hospitalized for resection of a falcotentorial tumor. During the ensuing 15 years she underwent multiple surgeries and sessions of radiation therapy for recurrent lesions. The exclusive location of her tumors in the subarachnoid space at the end of this 15-year period indicate CSF dissemination of the tumor. The tumor that was resected when the patient was 48 years old and the latest resected lesion were analyzed by performing immunohistological CD34, epithelial membrane antigen, vimentin, S100 protein, and reticulin staining, and determining the MIB-1 labeling index (LI). Most of the results were identical, and both tumors were diagnosed as SFT according to a staining pattern that showed a strong and diffuse positive reaction for CD34. Nevertheless, the authors noted that the MIB-1 LI increased from less than 1% in the original tumor to 13% in the latest tumor. The increased proliferation of MIB-1 indicates that the malignant transformation could have occurred during tumor recurrence with CSF dissemination.

Antigens, CD34↗

Molecular analysis of the rhabdoid predisposition syndrome in a child: a novel germline hSNF5/INI1 mutation and absence of c-myc amplification.

The authors report a case of the rhabdoid predisposition syndrome (RPS) secondary to a germline hSNF5/INI1 mutation, whose brain tumor was originally unclassified but finally diagnosed as an atypical teratoid/rhabdoid tumor (AT/RT) by molecular analysis. A 7-month-old infant presented with hydrocephalus secondary to a huge pineal tumor and subsequently developed a renal rhabdoid tumor. The histology of the brain tumor was initially undetermined; however, an AT/RT was strongly suspected because of her clinical course. Mutational screening of the hSNF5/INI1 gene by heteroduplex and direct sequence analysis detected a missense mutation at codon 53 (CGA --> TGA, arginine --> stop) in both tumors, as well as in normal tissue of the kidney. Polymerase chain reaction (PCR)-based microsatellite analysis showed in both tumors allelic loss on chromosome arm 22q to which the hSNF5/INI1 gene maps. c-myc amplification was examined by differential PCR but not detected. Histologic review of the brain tumor by immunohistochemistry confirmed focal expression of epithelial membrane antigen and smooth muscle actin. These findings suggest that the brain tumor was really an AT/RT as a component of RPS secondary to a germline hSNF5/INI1 mutation. The present mutation has never been reported in the literature.

Brain Neoplasms↗

Oxidized galectin-1 stimulates the migration of Schwann cells from both proximal and distal stumps of transected nerves and promotes axonal regeneration after peripheral nerve injury.

Oxidized galectin-1 has recently been identified as a key factor that plays important roles in initial axonal growth in injured peripheral nerves. The aim of this study was to investigate the effects of oxidized galectin-1 on regeneration of rat spinal nerves using acellular autografts (containing no viable cells) and allografts (containing no cell membranes) with special attention to the relationship between axonal regeneration and Schwann cell migration. Immunohistochemically, endogenous galectin-1 was expressed in dorsal root ganglion (DRG) neurons, spinal cord motoneurons, and axons and Schwann cells in normal sciatic nerves. Administration of oxidized recombinant human galectin-1 (rh-gal-lox, 5 ng/ml) in autograft model promoted axonal regeneration from motoneurons as well as from DRG neurons; this was confirmed by a fluorogold tracer study (p < 0.05). Anti-rh-gal-1 antibody (30 microg/ml) strongly inhibited axonal regrowth (p < 0.05). Pretreatment of allografts with rh-gal-lox stimulated the migration of Schwann cells not only from proximal stumps but also from distal stumps into the grafts, resulting in accelerated axonal regeneration (p < 0.05). Moreover, Schwann cell migration preceded the axonal growth in the presence of exogenous rh-gal-lox in the grafts. These results strongly suggest that local administration of exogenous rh-gal-lox promotes the migration of Schwann cells followed by axonal regeneration from both motor and sensory neurons, resulting in acceleration of neuronal repair. This technique may also be of value in the repair of human nerves.

Animals↗

Frequent LOH at chromosome 12q22-23 and Apaf-1 inactivation in glioblastoma.

Glioblastoma (GB) often has loss of heterozygosity on the chromosomes, 1p, 10p, 10q, 11p, 17p, 19q, 22q, and several others. In the case of chromosome 12q, however, it remains to be seen whether LOH occurs. Apaf-1, the apoptotic protease activating factor-1, located at chromosome 12q22-23, is a major effecter of the p53 mediated apoptosis pathway, and Apaf-1 inactivation due to chromosome 12q22-23 LOH and hypermethylation may be involved in some of the neoplasms in malignancy. However, little is known about the frequency of the 12q22-23 LOH or the state of Apaf-1 in GB. To elucidate their involvement in GB, we analyzed a series of 33 GBs for chromosome 12q22-23 LOH, Apaf-1 mRNA expression, and Apaf-1 protein expression, using microsatellite analysis, reverse transcription (RT)-PCR analysis, and immunohistochemical (IHC) analysis, respectively. We also evaluated if and how the 12q22-23 LOH correlated with the p53 gene mutation and EGFR gene amplification. Chromosome 12q22-23 LOH was detected in 14 (42%) of 33 cases. Among the examined cases with LOH at 12q22-23, a low expression of Apaf-1 mRNA was detected in 9 (69%) of 13 cases, and a low expression of Apaf-1 protein was detected in 12 (86%) of 14 cases. The 12q22-23 LOH was significantly correlated with low expression of mRNA and protein (p<0.05, p<0.001 respectively). The p53 gene mutation and EGFR gene amplification were found in 13 cases (39%) and 8 cases (24%), respectively, and these gene alterations were inversely correlated. However, 12q22-23 LOH had no correlations with the p53 gene mutation or EGFR gene amplification. Six of 9 GBs (67%) with neither p53 gene mutation nor EGFR gene amplification tested positive for 12q22-23 LOH. These GBs are likely to belong to another subset independent from the 2 common genetic subsets in GB (one with p53 gene mutation and without EGFR gene amplification, and the other with EGFR gene amplification and without p53 gene mutation). Twenty-three (70%) out of the 33 GBs with the 12q22-23 LOH also tested positive for Apaf-1 inactivation or p53 gene mutation. This high frequency of alterations in the apoptosis-associated factors prompts a speculation that abrogation of the Apaf-1 and p53 mediated apoptosis pathway may play an important role in the tumorigenesis of GB.

Adult↗

Metastasis of breast cancer to intracranial meningioma: case report.

Metastasis of systemic cancer to intracranial tumors is a rare event. The authors report a case of 49-year-old woman with such occurrence, whose breast cancer metastasized to a preexisting parasagittal meningioma at a postoperative interval of 1.5 years. She was admitted to our hospital because of progressive right hemiparesis. Magnetic resonance imaging revealed newly emerged perifocal edema and inhomogeneous contrast enhancement of the meningioma. High choline/creatine ratio and lactate/lipid peak on proton magnetic resonance spectroscopy suggested malignancy. She underwent a tumor resection, and pathologic examination revealed intratumoral metastasis of breast cancer in a transitional meningioma. Immunoreactivity of E-cadherin was detected in both meningioma and breast cancer cells. It is suggested that abrupt appearance of symptoms, inhomogeneous enhancement, and perifocal edema of meningioma is a sign of intratumoral metastasis from systemic cancers.

Bone Neoplasms↗

A novel fibroblast growth factor receptor 2 mutation in Crouzon syndrome associated with Chiari type I malformation and syringomyelia.

OBJECT: It has been reported that due to premature synostosis of the lambdoid suture in the first 24 months of life, more than 70% of patients with Crouzon syndrome concurrently suffer from chronic tonsillar herniation (Chiari Type I malformation) and some (20%) associated syringomyelia. The goal of the present study was to examine mutations in the fibroblast growth factor receptor (FGFR) genes in Crouzon syndrome and its related conditions. METHODS: Five patients were studied: three with Crouzon syndrome (one sporadic and two familial), one with sporadic Chiari I with syringomyelia, and one with unilateral lambdoid synostosis. Deoxyribonucleic acid was screened for FGFR1-3 mutations by using single-strand conformational polymorphism and subsequent direct sequencing. Two types of missense mutations were detected in the FGFR2 gene, Cys342Trp (1205, TGC --> TGG) in a patient with sporadic Crouzon syndrome and Tyr281Cys (1021, TAC --> TGC) in two siblings (brother and sister) with familial Crouzon syndrome, respectively. The former has been reported only in sporadic cases but the latter has not previously been identified. A polymorphism in the FGFR3 gene, Asn294Asn (882, AAT --> AAC), was also detected in three patients. No mutation was found in the patient with sporadic Chiari I with syringomyelia. CONCLUSIONS: The FGFR2 missense mutation was detected in Crouzon syndrome but not in sporadic Chiari I with syringomyelia or lambdoid synostosis. A novel FGFR2 mutation, Tyr281Cys, was found in familial Crouzon syndrome with Chiari I and syringomyelia. It may be informative to look for this in patients with Crouzon syndrome and associated syringomyelia.

Adolescent↗

Genetic differences between neurocytoma and dysembryoplastic neuroepithelial tumor and oligodendroglial tumors.

OBJECT: Because of their histological similarities, it is occasionally difficult to differentiate neurocytoma and dysembryoplastic neuroepithelial tumor (DNT) from oligodendroglial tumors. This study was conducted to investigate genetic differences among these tumor types in terms of loss of heterozygosity on chromosomes 1p and 19q, and p53 gene mutation. METHODS: A total of 24 tumors were analyzed, consisting of eight central neurocytomas, three DNTs, seven oligodendrogliomas, four oligoastrocytomas, and two undetermined extraventricular tumors with neurocytoma features (ETNFs). Allelic loss was determined using microsatellite markers that cover the common deletions on chromosomes 1p and 19q in oligodendrogliomas. A p53 gene mutation was identified using polymerase chain reaction-single-strand conformation polymorphism analysis and subsequent direct sequencing. Immunohistochemical studies with synaptophysin and electron microscopy investigations were also conducted. Allelic loss on 1p and 19q was detected in six oligodendrogliomas (86%) and in three oligoastrocytomas (75%), but in none of the central neurocytomas or DNTs. A p53 missense mutation was detected at codon 161 (GCC-->ACC, Ala-->Thr) in only one oligoastrocytoma without allelic loss. Synaptophysin was expressed in all central neurocytomas and DNTs, in three oligodendrogliomas (43%), and in three oligoastrocytomas (75%). Of the ETNFs, one demonstrated synaptophysin expression and neural ultrastructures but lacked genetic alterations, whereas the other showed allelic loss on 1p and 19q but was negative immunohistochemically and ultrastructurally. The former was diagnosed as a potential intraparenchymal neurocytoma and the latter as an oligodendroglioma. CONCLUSIONS: Despite histological similarities, central neurocytomas and DNTs are genetically distinct from oligodendroglial tumors. Examination for allelic loss on 1p and 19q and for p53 mutation can be useful for making this distinction.

Adolescent↗

Cyanotic breath-holding spell: a life-threatening complication after radical resection of a cervicomedullary ganglioglioma.

Cyanotic breath-holding spell is a benign and self-limiting disease of young children but occasionally associated with sudden, unexpected death. The authors report a rare case in a 2-year-old girl with a severe form that started after radical resection of a cervicomedullary ganglioglioma. She was admitted to our hospital because of delayed and unstable gait. Since magnetic resonance imaging showed a cervicomedullary tumor, she underwent a radical resection and histology showed the tumor to be a ganglioglioma. Postoperatively, the function of the lower cranial nerves and cerebellum deteriorated and hemiparesis on the left became apparent, but she returned to the preoperative state in a few months. In addition, mild sleep apnea (Ondine curse) and severe cyanotic breath-holding spells occurred. The former responded to medication but the latter failed and continued several times per day with a rapid onset and progression of hypoxemia, loss of consciousness, sweating and opisthotonos. Five months after the operation, the patient returned home with a portable oxygen saturation monitor equipped with an alarm. This case indicates that cyanotic breath-holding spell, as well as sleep apnea, is critical during the early postoperative period. This is the first report observing that such spells may occur as a complication of radical resection of a cervicomedullary tumor.

Apnea↗