Biomedical subjects

Kiyoshi Mukai

Publications and source records attributed to Kiyoshi Mukai.

At least 19 recordsLinked to original sources

PubMed2006

Regional DNA hypermethylation and DNA methyltransferase (DNMT) 1 protein overexpression in both renal tumors and corresponding nontumorous renal tissues.

To evaluate the significance of altered DNA methylation during renal tumorigenesis, tumorous tissues (T) and corresponding nontumorous renal tissues (N) from 94 patients with renal tumors, and normal renal tissues (C) from 16 patients without renal tumors were investigated. DNA methylation status on CpG islands of the p16, human MutL homologue 1 (hMLH1), von-Hippel Lindau (VHL) and thrombospondin-1 (THBS-1) genes and the methylated in tumor (MINT) -1, -2, -12, -25 and -31 clones and DNA methyltransferase (DNMT) 1 expression were examined by bisulfite modification and immunohistochemistry, respectively. The average number of methylated CpG islands was significantly higher in N than in C, and was even higher in T. The average number of methylated CpG islands in N was significantly correlated with a higher histological grade of corresponding conventional renal cell carcinomas (RCCs). The average number of methylated CpG islands in RCCs was significantly correlated with macroscopic configuration with extranodular or multinodular growth, higher histological grade, infiltrating growth pattern and vascular involvement. The recurrence-free survival rate of patients with RCCs showing accumulation of DNA methylation was significantly lower than that of patients not showing this feature. The incidence of nuclear immunoreactivity for DNMT1 tended to be higher in proximal tubules from N than in those from C, and was significantly higher in RCCs. From the viewpoint of altered DNA methylation, N is at the precancerous stage, and N showing accumulation of DNA methylation may generate more malignant RCCs. Regional DNA hypermethylation may be associated with renal tumorigenesis from a precancerous condition to malignant progression and become a predictor of patient prognosis.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Coexpression of actin-related protein 2 and Wiskott-Aldrich syndrome family verproline-homologous protein 2 in adenocarcinoma of the lung.

PURPOSE: Highly invasive and metastatic cancer cells, such as adenocarcinoma of the lung cells, form irregular protrusions by assembling a branched network of actin filaments. In mammalian cells, the actin-related protein 2 and 3 (Arp2/3) complex initiates actin assembly to form lamellipodial protrusions by binding to Wiskott-Aldrich syndrome (WASP)/WASP family verproline-homologous protein 2 (WAVE2). In this study, colocalization of Arp2 and WAVE2 in adenocarcinoma of the lung was investigated to elucidate its prognostic value. EXPERIMENTAL DESIGN: Immunohistochemical staining of Arp2 and WAVE2 was done on mirror sections of 115 adenocarcinomas of the lung from pathologic stage IA to IIIA classes. Kaplan-Meier disease-free survival and overall survival curves were analyzed to determine the prognostic significance of the coexpression of Arp2 and WAVE2. RESULTS: Immunoreactivity for both Arp2 and WAVE2 was detected in the same cancer cells in 78 (67.8%) of the 115 lung cancer specimens. The proportion of cancer cells expressing both Arp2 and WAVE2 was significantly higher in cases with lymph-node metastasis (P = 0.0046), and significantly lower in bronchioloalveolar carcinomas (P < 0.0001). The patients whose cancer cells coexpressed them had a shorter disease-free survival time (P < 0.0001) and overall survival time (P < 0.0001). Multivariate Cox regression analysis revealed that coexpression of Arp2 and WAVE2 is an independent risk factor for tumor recurrence. CONCLUSIONS: Coexpression of Arp2 and WAVE2 is correlated with poorer patient outcome, and may be involved in the mechanism of cancer metastasis.

Actin-Related Protein 2↗

PubMed2006

Chlamydia psittaci in ocular adnexal lymphoma: Japanese experience.

We searched for the Chlamydia psittaci DNA the touchdown enzyme time release PCR (TETR-PCR) in 23 specimens from 21 patients with ocular adnexal lymphoproliferative disorders, including 12 patients with MALT lymphoma to identify C. psittaci infection. Southern hybridization of the PCR product using the C. psittaci-specific probe failed to detect C. psittaci, although three samples appeared to be positive by ethidium bromide staining. This indicates that technical approach for detecting C. psittaci infection in ocular adnexal lymphoma might be an essential in disclosing this association.

Adult↗

PubMed2006

A multicenter randomized controlled trial to evaluate the effect of adjuvant cisplatin and 5-fluorouracil therapy after curative resection in cases of pancreatic cancer.

BACKGROUND: There have been few randomized controlled clinical trials until now to determine the effectiveness of adjuvant treatments for pancreatic cancer, and the results reported so far are inconsistent. METHODS: Patients with invasive ductal pancreatic cancer who underwent radical surgery with clear histological margins at 11 Japanese institutions were enrolled and randomly assigned to one of two groups: surgery-alone group (no further treatment after surgery) and the surgery + chemotherapy group [two courses of postoperative adjuvant systemic chemotherapy with cisplatin (80 mg/m(2), Day 1) and 5-fluorouracil (500 mg/m(2)/day, Days 1-5)]. Patients with a positive resectional margin or with resected distant metastases were excluded from the trial in order to minimize the influence of residual cancer. RESULTS: Between 1992 and 2000, 89 patients were randomized into the two arms of the trial (45 patients to the surgery + chemotherapy arm and 44 patients to the surgery-alone arm). Four patients in total were found to be ineligible (three in the surgery + chemotherapy group and one in the surgery-alone group). The baseline characteristics were comparable between the two groups. In the surgery + chemotherapy group, four patients did not receive the adjuvant treatment because of patient refusal. Toxicity was minor and acceptable among the eligible patients in the surgery + chemotherapy group. The estimated 5-year survival rates were 26.4% in the surgery + chemotherapy group and 14.9% in the surgery-alone group, and the median duration of survival was 12.5 months and 15.8 months, respectively. The recurrence rates at 5 years were 73.6 and 80.8%, respectively, in the surgery + chemotherapy and the surgery-alone groups. The differences in the survival and recurrence rates between the two groups were not statistically significant. CONCLUSIONS: Postoperative adjuvant chemotherapy using cisplatin and 5-fluorouracil was safe and well tolerated; however, no clear survival benefit could be demonstrated.

Aged↗

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↗

PubMed2006

Hypereosinophilia in a patient with invasive thymoma with clonal T-lymphocyte expansion expressing CD4, CD8, and CD25 antigens.

We report the case of a patient with hypereosinophilia and invasive thymoma harboring probable clonal proliferation of CD4+, CD8+, and CD25+ T-lymphocytes. A 64-year-old woman had eosinophilia (14.1 x 10(9)/L) and an anterior mediastinal tumor with elevated levels of serum immunoglobulin E (609.8 mg/dL) and interleukin 5 (239 pg/mL). Bone marrow aspirate showed marked infiltration by morphologically normal eosinophils with a normal karyotype but no FIP1L1-PDGFRA fusion gene. Flow cytometric analysis revealed an increasing number of CD3+/CD25+ lymphocytes in the peripheral blood, and the resected thymoma had infiltrated lymphocytes with CD4/CD8/CD25 antigens. Moreover, the thymoma had T-cell receptor rearrangements with a cytogenetically clonal nature, ie, t(2;4)(p22;q26). Although the number of patients with thymoma showing hypereosinophilia is small, this case suggests that a subset of patients with thymoma may have clonal expansion of T-lymphocytes with abnormal phenotypes that affect clinical manifestations, including hypereosinophilia.

Antigens, CD↗

PubMed2006

Differential expression of N-cadherin and E-cadherin in normal human tissues.

E-cadherin, which expressed in various epithelial tissues, is important for the maintenance of normal epithelial phenotypes. However, the distribution of N-cadherin in normal human tissues has not been defined systemically. In the present study, we employed a sensitive, reliable immunohistochemical detection system for N-cadherin on formalin-fixed, paraffin-embedded tissue sections, and succeeded in demonstrating N- and E-cadherin protein expressions and their distribution in normal human tissues. E-cadherin immunoreactivity was detected in all the epithelial tissues examined, except for the adrenal cortical cells and granulosa cells. N-cadherin was selectively expressed on epithelial cells of the thymus, pituitary, pancreas, liver, adrenal, endometrium of the uterus, ovary, and stomach as well as in neuronal tissues. Double immunostaining revealed that N-cadherin expression was closely associated with the hormone-producing ability of cells in the pancreas and pituitary. Thus, this study indicated the possibility that N-cadherin is selectively expressed in relation to hormonal regulation in some organs and plays different functions in different situations. The method presented here should prove useful for the further investigation of the N-cadherin expression and function in several disease conditions on formalin-fixed, paraffin-embedded archival tissues.

Cadherins↗

PubMed2005

Involvement of Arp2/3 complex in MCP-1-induced chemotaxis.

The migrating monocyte shows dynamic actin polymerization in response to MCP-1. We investigated the involvement of the actin-related protein 2 and 3 complex (Arp2/3 complex) during chemotaxis of a human monocyte cell line (THP-1). To clarify whether the Arp2/3 complex directly polymerizes actin in response to MCP-1 stimulation, THP-1 cells were transfected with complementary DNA constructs encoding ScarWA. In ScarWA-transfected cells, neither recruitment of Arp2/3 complex at the leading edge nor actin polymerization was detected. Indeed, migration induced by MCP-1 was almost completely blocked. At the same time, transfection also interfered with the recruitment of integrin beta-1 at the leading edge and reduced affinity binding to fibronectin. Immunoprecipitation with an anti-Arp2 antibody showed that integrin beta-1 and WASP were co-precipitated under the condition of MCP-1 stimulation. These results indicate that interaction between the Arp2/3 complex and WASP stimulates actin polymerization and integrin beta-1-mediated adhesion during MCP-1-induced chemotaxis of THP-1 cells.

Actin-Related Protein 2↗

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

Accumulation of ubiquitin-conjugated cytokeratin fragments in tumor cells.

Ubiquitin regulates cell functions by modifying various proteins, and cytokeratin (CK) is one of the targets of ubiquitilation. Accumulation of modified CK in various cancers has been demonstrated, and the modified CK increases the aggressiveness of the cancer by disrupting the cytoplasmic CK network and allows them to move freely. The phenotype of the cancer cells may be altered in such a way as to facilitate invasion and metastasis. Modified CK also deregulates mechanisms of mitosis and apoptosis, and leads to immortalization. Therapeutic targeting of ubiquitin or ubiquitilated proteins may reduce the malignant potential of cancer cells.

Humans↗

PubMed2005

Peripheral T-cell lymphoma together with myelofibrosis with elevated plasma transforming growth factor-beta1.

Myelofibrosis is usually observed in myeloproliferative disorders, such as chronic myeloid leukemia. However, there are only a few reports showing an association between T-cell lymphoma and myelofibrosis. We report a case of peripheral T-cell lymphoma, unspecified (diffuse large cell) type, involving the bone marrow that was associated with severe myelofibrosis. In the present case, the plasma concentration of transforming growth factor-beta1 (TGF-beta1) was increased to 8.95 ng/ml (normal range: 1.56-3.24 ng/ml). No lymphadenopathy or skin lesions were observed during the entire clinical course. Although the mechanism of secondary myelofibrosis is still unclear, elevated plasma TGF-beta1 might be involved in the pathogenesis of bone marrow fibrosis in the present case.

Aged↗

PubMed2005

Hepatosplenic αβ T-cell lymphoma with myelodysplastic syndrome.

We describe a patient with hepatosplenic 33 T-cell lymphoma who showed pancytopenia and myelodysplasia. A 35-year-old man was admitted with fever, pancytopenia, and hepatosplenomegaly but with no lymphadenopathy. We also found trilineage myelodysplasia in the bone marrow on his first admission. The patient had high fever and anemia but no evidence of infection and was tentatively treated with prednisolone. This treatment resulted in a transient improvement of the cytopenia and a reduction of spleen size. However, 10 months after the first manifestation, progression of the splenomegaly and fever became apparent, and a splenectomy was performed. The pathologic findings for the spleen showed diffuse and disseminated infiltration of medium- to large-sized T-lymphocytes in the splenic red pulp. These cells were immunohistochemically positive for CD3, CD5, CD7, CD8, CD16, CD56,T-cell receptor 33 (TCR33),T-cell intracellular antigen 1, and granzyme B but were negative for CD4, CD30, CD57, and TCR33. These data suggested a diagnosis of hepatosplenic 33 T-cell lymphoma. A Southern blot analysis revealed gene rearrangement of the TCR 3-chain gene but not the immunoglobulin heavy chain gene in the spleen cells. An in situ hybridization analysis for the Epstein-Barr virus revealed negative results. The patient received 8 courses of combination chemotherapy and achieved a partial remission; however, the dysplastic features of the marrow cells persisted after the partial remission was obtained. Additional treatment with allogeneic bone marrow transplantation resulted in a transient complete remission; however, the patient relapsed 11 months later. Because he had experienced no lymphadenopathy and showed dysplastic features in the bone marrow, the diagnosis was highly dependent on the pathologic findings for the resected spleen.

Adult↗

PubMed2005

[A case of pulmonary intravascular lymphoma treated with CHOP chemotherapy plus rituximab].

We report a case of pulmonary intravascular lymphoma of large B cell type in a 72-year-old woman. She had a one-month history of fever and dry cough before admission. Chest X-ray revealed ground glass shadow in both lung fields, and the high-resolution CT disclosed centrilobular distribution of ground glass opacities. Transbronchial lung biopsy demonstrated large lymphoid cells in the capillaries of alveolar septa. The tumor cells showed strong immunohistochemical reactivity to CD 20. After combined treatment with CHOP and rituximab, clinical symptoms, laboratory and radiological findings were improved. As with diffuse large B cell lymphoma, CHOP chemotherapy plus rituximab may prove useful as a standard regimen for pulmonary intravascular lymphoma.

Aged↗

PubMed2005

[Pathologic characteristics and evaluation of the pancreatic cancer].

Ductal adenocarcinoma is the most common tumor type of cancer of the pancreas. It is generally a poorly demarcated, white to grey-solid tumor located in the pancreatic head. Histologically, it is often well-to moderately-differentiated tubular adenocarcinoma along with marked desmoplastic change. There are three well-defined precursors to invasive cancer; mucinous cystic neoplasms (MCNs), intraductal papillary mucinous neoplasms (IPMNs), and pancreatic intraepithelial neoplasia PanINs. PanIN is now considered to be a precursor of pancreatic ductal adenocarcinoma based on molecular studies. However, it is difficult to distinguish between small IPMNs and PanINs pathologically because both of them often show similar epithelium with cytoplasmic mucin. IPMNs and MCNs can form similar invasive carcinomas such as tubular adenocarcinoma and/or mucinous carcinoma. Another focus of this review is the issue of pathologic evaluation of the surgically resected specimens. Histologic grading and pathologic staging of each case are important especially in terms of the clinical aspects. Careful attention should be paid to the processes and/or criteria of pathologic diagnosis.

Adenocarcinoma↗

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

WHO histologic classification is a prognostic indicator in thymoma.

BACKGROUND: The histologic classification of thymoma has remained a subject of controversy for many years. In 1999, the World Health Organization Consensus Committee published a histologic typing system for tumors of the thymus. METHODS: We reclassified a series of 100 thymomas resected at Tokushima University Hospital and four affiliated hospitals in Japan between 1973 and 2001 according to the World Health Organization histologic classification and reported its clinicopathologic relationship and prognostic relevance. RESULTS: There were 8 type A, 17 type AB, 27 type B1, 8 type B2, 12 type B3, and 28 type C thymomas. The frequency of invasion to neighboring organs increased according to tumor subtype in the order A (0%), AB (6%), B1 (19%), B2 (25%), B3 (42%), and C (89%). There was no recurrence in patients with type A, AB, or B2 thymoma. The recurrence rates of patients with B1, B3, or C thymoma were 15%, 36%, and 47%, respectively. The disease-free survival rates were 100% for types A and AB, 83% for types B1 and B2, 36% for type B3, and 28% for type C thymoma at 10 years. There were significant differences in disease-free survival between types A and AB and types B1 and B2 (p = 0.0436), and between type B3 and type C (p = 0.042). By multivariate analysis, only Masaoka clinical stage (p = 0.002) showed significant independent effects on disease-free survival. The 10-year survival rates of types A and AB, types B1 and B2, type B3, and type C thymoma were 100%, 94%, 92%, and 58%, respectively. CONCLUSIONS: The current study confirmed the World Health Organization histologic classification as a good prognostic factor.

Adolescent↗