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Masahiko Kuroda

Publications and source records attributed to Masahiko Kuroda.

18 recordsLinked to original sources
PubMed2006

Generation of the novel monoclonal antibody against TLS/EWS-CHOP chimeric oncoproteins that is applicable to one of the most sensitive assays for myxoid and round cell liposarcomas.

The fusion oncoproteins, TLS-CHOP and EWS-CHOP, are characteristic markers for myxoid and round cell liposarcomas (MLS/RCLS). Especially, the peptide sequence of 26 amino acids corresponding to the normally untranslated CHOP exon 2 and parts of exon 3 (5'-UTR) is a unique structure for these chimeric proteins. In this report, we have generated monoclonal antibodies against the unique peptide sequence of TLS/EWS-CHOP oncoproteins. These antibodies reacted with TLS-CHOP fusion protein, but not reacted with normal TLS and CHOP proteins by Western blot analysis. In addition, one of the antibodies also recognized the chimeric oncoprotein in archival paraffin-embedded tissue samples of MLS/RCLS. The oncoprotein was detectable by the antibody even in the paraffin-embedded tissue samples whose mRNAs were too degraded to be detected by a nested reverse transcription-polymerase chain reaction-based assay. Thus, the molecular assay using the novel antibody is expected to be one of the most sensitive diagnostic assays for MLS/RCLS.

Adult↗
PubMed2005

Effects of 3-methylcholanthrene on the transcriptional activity and mRNA accumulation of the oncogene hWAPL.

hWAPL is a human oncogene associated with uterine cervical cancer. Here, we demonstrate that hWAPL transcription is induced by 3-methylcholanthrene (3-MC) in the cervical carcinoma-derived cell line SiHa. hWAPL transcription was analyzed with evaluation of the mRNA and heterogeneous nuclear RNA (hnRNA) levels by quantitative real time PCR analysis. Flow cytometric analysis suggested that the alteration of hWAPL mRNA levels is independent of cell cycle profile. We also found that DMSO and some components of FBS affect hWAPL transcription. Interestingly, when the aryl hydrocarbon receptor (AhR) function was inhibited by alpha-naphthoflavone (ANF), the induction of hWAPL transcription by 3-MC was greater than that in AhR-functioning normal cells. These observations suggest that there are complex mechanisms regulating the transcription of hWAPL. Furthermore, mRNA level of a mouse homolog of hWAPL in mouse uterus was induced by 3-MC injection into the abdominal cavity. Thus, some effects from 3-MC exposure on uterus may be mediated by the unscheduled overexpression of hWAPL.

Animals↗
PubMed2005

A dioxin sensitive gene, mammalian WAPL, is implicated in spermatogenesis.

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an endocrine disruptor that produces a variety of toxic effects. We have isolated a mouse homolog of the hWAPL gene, termed mouse WAPL (mWAPL), as a target of TCDD by cDNA representational difference analysis from mouse embryonic stem cells. A statistically significant increase in mWAPL expression was observed at 0.1 microM TCDD in AhR-/- mouse embryonic fibroblast cells. Interestingly, at 1 microM TCDD, mWAPL mRNA levels decreased in AhR+/+ cells, but further increased in AhR-/- cells. hWAPL and mWAPL were highly expressed only in testes among normal tissue samples, and we observed mWAPL localization in the synaptonemal complex of testicular chromosomes. In addition, mouse testes decreased the expression of mWAPL mRNA after a single intraperitoneal injection of TCDD. Thus, mammalian WAPL such as hWAPL and mWAPL may be involved in spermatogenesis and be target genes mediating the reproductive toxicity induced by TCDD.

Amino Acid Sequence↗
PubMed2005

Undisrupted pulse wave on pulse oximeter display monitor at cardiac arrest in a surgical patient.

We have encountered a case of cardiac arrest during anesthesia care in which an application of a new-generation pulse oximetry technology led to a misleading interpretation of the patient's true condition. Just after manipulation of the peritoneum, the heart rhythm suddenly became asystole, while the ECG showed a standstill and an arterial pressure wave was absent. However, the Datex-Ohmeda AS/3 Patient Monitor connected to the Masimo SatShare Waveform Generator feature continued to display a pulse wave with a reading of 99%. Because we assumed the reading to be reliable, we took no immediate action. However, the ECG standstill and flattened arterial wave lasted for about 10 s, with no pulse at the common carotid artery; thus, 0.5 mg atropine and 4 mg ephedrine were given and chest compression performed using ventilation with oxygen. About 20 s later, the heart rhythm reappeared, which was monitored by the ECG and arterial pulse wave. This incident demonstrates the importance of becoming familiar with a new technology; otherwise, we will fall into medical errors.

Adult↗
PubMed2005

Detection of fusion genes in sarcomas using paraffin-embedded tissues.

Many sarcomas are characterized by specific recurrent chromosomal translocations resulting in gene fusions. The genes involved in almost all of these translocations have been cloned, greatly changing sarcoma diagnosis. At the biological level, these chromosomal translocations produce highly specific fusion genes that encode key molecules for tumor development. The clinical correlation between these translocation-derived genetic markers and discrete histopathological entities has been remarkable. Today, detection of fusion genes plays a crucial role in the diagnosis of sarcomas that harbor atypical clinical or pathological presentations. The focus of this brief review is the recent impact that cytogenetic and molecular detection of these translocations has had on sarcoma diagnosis using paraffin-embedded sections.

Animals↗
PubMed2004

Alteration of chromosome positioning during adipocyte differentiation.

Chromosomes are highly restricted to specific chromosome territories within the interphase nucleus. The arrangement of chromosome territories is non-random, exhibiting a defined radial distribution as well as a preferential association with specific nuclear compartments, which indicates a functional role for chromosome-territory organization in the regulation of gene expression. In this report, we focus on changes in adipocyte differentiation that are related to a specific chromosomal translocation associated with liposarcoma tumorigenesis, t(12;16). We have examined the relative and radial positioning of the chromosome territories of human chromosomes 12 and 16 during adipocyte differentiation, and detected a close association between the territories of chromosomes 12 and 16 in differentiated adipocytes, an association not observed in preadipocytes. Although further studies are required to elucidate the underlying reasons for the adipocyte-specific translocation of chromosomes 12 and 16, our observations indicate that alteration of relative chromosome positioning might play a key role in the tumorigenesis of human liposarcomas. In addition, these results demonstrate the potential impact of higher order chromatin organization on the epigenetic mechanisms that control gene expression and gene silencing during cell differentiation.

Adipocytes↗
PubMed2004

Expression of a novel human gene, human wings apart-like (hWAPL), is associated with cervical carcinogenesis and tumor progression.

In Drosophila melanogaster, the wings apart-like (wapl) gene encodes a protein that regulates heterochromatin structure. Here, we characterize a novel human homologue of wapl (termed human WAPL; hWAPL). The hWAPL mRNA was predominantly expressed in uterine cervical cancer, with weak expression in all other normal and tumor tissues examined. hWAPL expression in benign epithelia was confined to the basal cell layers, whereas in dysplasias it increasingly appeared in more superficial cell layers and showed a significant correlation with severity of dysplasia. Diffuse hWAPL expression was found in all invasive squamous cell carcinomas examined. In addition, NIH3T3 cells overexpressing hWAPL developed into tumors on injection into nude mice. Furthermore, repression of hWAPL expression by RNA interference induced cell death in SiHa cells. These results demonstrate that hWAPL is associated with cell growth, and the hWAPL expression may play a significant role in cervical carcinogenesis and tumor progression.

Animals↗
PubMed2004

Human DNA damage checkpoints and their relevance to soft tissue sarcoma.

Soft tissue sarcoma (STS) is a malignant neoplasm, arising in mesenchymal tissues, that is difficult to treat clinically because it can be highly resistant to chemo-radiotherapy. At present, the mechanism of that resistance remains unclear. Cell cycle checkpoints engender strict control of cell proliferation, arresting the cell cycle to provide time for repair or apoptosis when DNA damage is induced by unprogrammed extrinsic events. These pathways involve at least two checkpoints: one at the G1/S transition and one at the G2/M transition. The p53 gene, which is mutated in several malignant tumors, plays an important role in DNA repair at the G1/S transition; however, there is little information on the G2/M checkpoint in STS. In the present study, several proteins (phospho-p53, -cdc25, -cdc2, -Chk1 and -Chk2) involved in checkpoint pathways were investigated using immunohistochemistry in STS specimens. Most STSs maintain a well-preserved G2/M checkpoint despite the loss of the G1/S checkpoint (phospho-p53: 4.9% (2/41); -cdc25: 41% (17/41); -cdc2: 61% (25/41); -Chk1: 29% (12/41); -Chk2: 46% (19/41)). Furthermore, in a postoperative chemotherapy case the number of cells positive for phospho-cdc25 and -Chk2 was higher in a recurrent tumor than in the primary tumor (n = 7, P = 0.046 < 0.05, Wilcoxon signed-ranks test). These findings indicate that the G2/M checkpoint pathway is well preserved and might contribute to the chemotherapeutic resistance associated with STS.

Adolescent↗
PubMed2003

Expression of cyclooxygenase-2 in chondroblastoma: immunohistochemical analysis with special emphasis on local inflammatory reaction.

To investigate the frequency and mechanism of the peritumoral inflammatory reaction in chondroblastoma, we evaluated the relationship between clinicoradiological findings and immunohistochemical expression of cyclooxygenase-2 (COX-2) in excised tumors. Twenty-one cases of chondroblastoma were studied. Imaging analysis was performed with radiographs and T1- and T2-weighted magnetic resonance images in all cases and with computed tomography scan and bone scintigraphy in some cases. Immunohistochemical study for COX-2 was carried out using formalin-fixed paraffin-embedded tissues. Periosteal reaction was observed in 6 cases (29%) and bone marrow edema in 15 cases (71%). Soft-tissue edema, joint effusion, and synovitis were found in 10 cases (48%), in 7 cases (33%), and in 9 cases (43%), respectively. Immunohistochemical expression of COX-2 in chondroblastoma cells was found in 15 of 21 cases (71%). The intensity of COX-2 immunoreactivity was correlated statistically with the presence of periosteal reaction, bone-marrow edema, soft-tissue edema, and synovitis. Our results indicate that activation of eicosanoid synthesis by COX-2 expression in the tumor itself is probably an important factor, inducing peritumoral inflammatory changes in chondroblastomas.

Adolescent↗
PubMed2003

Increased expression of IgE-dependent histamine-releasing factor in endometriotic implants.

A complex network of cytokines mediates the immunoregulatory responses leading to endometriosis. Recent intensive studies suggest that monocyte and T cell chemoattractants contribute to the inflammatory environment of endometriotic implants. The relationship between the inflammation present during endometriosis and the development of endometriotic implants in the peritoneal cavity remains unclear. On the other hand, the association between endometriosis and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; dioxin) exposure has been discussed in recent years, and our previous results revealed that IgE-dependent histamine-releasing factor (HRF) is inducible by TCDD. The present study aimed to clarify the expression, localization, and function of HRF in endometriosis. Northern blot analysis demonstrated that HRF is overexpressed in endometriotic implants. RT-PCR with Southern blot analysis, however, showed that HRF overexpression was not always accompanied by CYP1A1 induction in endometriotic implants, suggesting that HRF is inducible in endometriosis without exposure to TCDD. HRF is also inducible by macrophage colony-stimulating factor (M-CSF). Immunohistochemistry showed CD68-positive macrophages in the stroma of endometriotic implants, adjacent to regions with prominent HRF accumulation. HRF-overexpressing cells exhibited high implantation efficiency in comparison to control cells when the cells were injected into the peritoneal cavities of nude mice. These results suggest that the accumulation of macrophages in endometriotic implants induces HRF; the overexpression of HRF accelerates the growth of endometriotic implants.

3T3 Cells↗
PubMed2003

Cytoplasmic and/or nuclear staining of beta-catenin is associated with lung metastasis.

Beta-catenin is involved in cell motility in the extracellular matrix, and is expressed in normal and neoplastic mesenchymal cells. In order to clarify whether beta-catenin expression in the cytoplasm and/or nucleus is associated with a propensity for pulmonary metastasis in osteosarcoma, the LM8 murine osteosarcoma cell line with a high metastatic potential to the lung was compared with original Dunn cells in terms of the beta-catenin expression level. Both osteosarcoma cell lines lost membrane localization of beta-catenin. However, beta-catenin gene had no mutation in exon 3 by direct sequence analysis. A large number of LM8 cells showed diffuse cytoplasmic and/or nuclear staining of beta-catenin (30.8 per high power field (HPF)), while a much smaller number of Dunn cells showed expression of beta-catenin (7.7 per HPF). Cells with positive staining of beta-catenin were frequently seen at the invasive front and in intravenous tumor deposits within the metastatic lesions to the lung. Thus, LM8 cells express a larger amount of the beta-catenin protein than Dunn cells, as judged by immunoblot analysis. In five resected cases of pulmonary metastasis, translocation of beta-catenin to the cytoplasm and/or nucleus of osteosarcoma cells was detected, although seven primary osteosarcomas cells that did not metastasize for more than five years did not show beta-catenin expression. These data indicate that the cytoplasmic and/or nuclear staining of beta-catenin is a biological marker of metastatic potential of osteosarcoma to the lung.

Animals↗
PubMed2002

Stromal expression of CD10 in invasive breast carcinoma: a new predictor of clinical outcome.

CD10 is a cell surface neutral endopeptidase that is not consistently expressed in the stromal cells of the normal breast. Expression of CD10 is sometimes observed in the stromal cells of invasive ductal carcinoma, but its clinical significance has never been studied. Immunohistochemical examination of CD10 was performed in 123 cases of breast cancer. The median follow-up period of all patients was 8.0 years, and univariate and multivariate analyses were performed to evaluate the prognostic significance of stromal CD10 expression. There was no staining in the stromal cells of 13 non-invasive ductal carcinomas or normal breast tissue. Of 110 invasive ductal carcinomas, 20 cases (18%) in which more than 10% of the stromal cells stained positive throughout the cancer tissue were judged "positive". The frequency of positive stromal staining was significantly higher in the cases with axillary lymph-node metastasis ( P=0.038), but there were no correlations between stromal CD10 expression and age, tumor size, histologic grade, or clinical stage. The patients whose tumors contained CD10-positive stromal cells had a shorter metastasis-free interval ( P=0.0008). Univariate analysis demonstrated that patients with lymph-node metastasis also had a significantly shorter metastasis-free interval (metastasis vs no metastasis; P=0.0318). In the multivariate analysis, only CD10 remained a significant predictor for time to recurrence ( P=0.0059), and CD10 was the single significant prognostic factor for overall survival in the univariate analysis ( P=0.0021). These results suggest that stromal expression of CD10 in breast cancer is an important novel prognostic factor.

Adult↗
PubMed2002

Angiomyoid proliferative lesion: an unusual stroma-rich variant of Castleman's disease of hyaline-vascular type.

The stroma-rich variant of Castleman's disease of hyaline-vascular type (CDHV) is a newly identified entity that shows overgrowth of a variety of stromal cells. Six CDHV patients showed proliferation of vasculature and actin-positive myoid cells in the expanded interfollicular (IF) area. There were three women and three men, and the median age was 29.5 years. Of the six lesions, four were located in the retroperitoneum, one in the neck, and one in the mediastinum. All patients were asymptomatic. Microscopically, the degree of widening of the IF area varied from slight overgrowth of the IF area (approximately 55% of the lymph node area) to vague nodularity and finally to the formation of prominent nodules. In the nodular lesions, lymph follicles were compressed and attenuated. In the IF area, there were numerous vessels and proliferation of spindle cells that possessed blunt nuclei. The long, slender, dendritic cytoplasms of the spindle cells were stained by alpha smooth muscle actin. The spindle cells were negative for desmin, CD34, factor VIII-related antigen, S-100, CD21, and CD68. No patient has had recurrence after simple excision. We maintain that these angiomyoid proliferative lesions in CDHV are of a hyperplastic nature. This condition encompasses proliferation of small vessels and myoid cells. Its characteristics include an asymptomatic, solitary nodule that predominantly develops in the retroperitoneum.

Actins↗
PubMed2002

Dioxin stimulates synthesis and secretion of IgE-dependent histamine-releasing factor.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD; dioxin) is the most toxic man-made member of the class of environmental pollutants represented by polychlorinated dibenzo-p-dioxins and dibenzofurans. TCDD produces a wide variety of toxic effects. However, the downstream genes targeted by TCDD and their relation to the diversity of dioxin toxicity symptoms are poorly understood. To identify the target genes of TCDD, we used a cDNA representational difference analysis (RDA) to compare the mRNA patterns of mouse embryonic stem (ES) cells that had and had not been exposed to TCDD. Here we show that TCDD stimulated the expression of IgE-dependent histamine-releasing factor (HRF) mRNA via an aryl hydrocarbon receptor (AhR)-dependent pathway. TCDD also induced the synthesis and secretion of HRF. To our knowledge, this is the first example of HRF being a direct transcriptional target of a toxic agent. HRF has previously been shown to induce histamine release in a dose-dependent manner, at least in vitro. Thus, our data suggest that "endocrine-disrupting" agents may have the potential to influence allergic disorders in the human body.

Animals↗
PubMed2002

TLS-CHOP target gene DOL54 expression in liposarcomas and malignant fibrous histiocytomas.

Downstream of the gene for the liposarcoma-associated fusion oncoprotein 54 (DOL54) is a target gene of the myxoid liposarcoma and round cell liposarcoma (M-LPS/RC-LPS) oncogene, TLS/FUS-CHOP. The DOL54 gene product is closely associated with adipogenic differentiation. DOL54 overexpression resulted in tumorigenicity when Chinese Hamster Ovary (CHO) cells were injected subcutaneously into nude mice. The biological significance of DOL54 expression for human malignant soft tissue tumors, however, has not yet been investigated. We examined TLS-CHOP and DOL54 expression in M-LPS/RC-LPS, well-differentiated liposarcoma and malignant fibrous histiocytoma (MFH), a tumor whose cellular origin has not been determined. We observed DOL54 expression in 50% of M-LPS/RC-LPS cases (in which TLS-CHOP was also expressed) and 33% of MFH cases, suggesting that a portion of MFH lesions may either derive from adipocytic precursor cells or have the potential to undergo adipogenic differentiation. In this manner, M-LPS/RC-LPS and MFH lesions may share tumorigenic characteristics, resulting from the unscheduled expression of DOL54.

Blotting, Northern↗
PubMed2002

Expression of CD10 by stromal cells during colorectal tumor development.

CD10 is a cell surface metalloprotease expressed by a variety of normal cell types, including lymphoid precursor cells, germinal center B lymphocytes, and some epithelial cells. We noticed that stromal cells of some cancers are positive for CD10. In this study, we investigated the role of CD10 produced by the stromal cells of colorectal neoplasms in the progression of colorectal neoplasms. Immunohistochemical examination of CD10 and p53 was performed in 169 colorectal epithelial neoplasms representing various stages of carcinogenesis. The results were correlated with the morphologic characteristics of the neoplasms. There was no expression of CD10 in the stromal cells of normal colorectal tissue. CD10-positive stromal cells were present adjacent to the tumor cells in 16 of 73 adenomas with mild or moderate dysplasia. More frequent expression of CD10 by the stromal cells was detected in adenomas with severe dysplasia (12 of 17), intramucosal carcinomas (10 of 16), and invasive carcinomas (50 of 63) than in adenomas with mild or moderate dysplasia (P < 0.0001). Expression of CD10 by > 10% of the stromal cells was detected only within the area of the invasive growth front of invasive carcinomas, not in adenomas and in only 1 of the intramucosal carcinomas. The difference between invasive and non invasive tumors was significant (P < 0.0001). The stromal expression of CD10 was significantly associated with the accumulation of p53 and a larger tumor size. These results indicate that CD10 expression is an integral part of colorectal carcinogenesis. CD10 expression seems to contribute to the invasion and thus probably facilitates metastasis.

Actins↗
PubMedDate not supplied

Extragastrointestinal stromal tumor of the greater omentum: case report and review of the literature.

Primary neoplasms of the greater omentum are rare. We report a case of omental tumors occurring in 58-year-old Japanese man. Ultrasonography showed multiple solid tumors in the abdomen and angiography identified the greater omentum as the precise location. The tumors were completely resected with the major part of the greater omentum and analyzed histologically, immunohistochemically, and genetically. Positive reactivity for CD117 (c-kit, a transmembrane tyrosine kinase receptor) and CD34, and the absence of TLS/FUS-CHOP rearrangement confirmed that the tumors were extragastrointestinal counterparts of a gastrointestinal stromal tumor. Although the higher mitotic activity measured by the Ki-67 labeling ratio suggests the malignant potential of this tumor, there was no recurrence at the 20-month follow-up.

Adult↗