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Tomohiro Kinoshita

Publications and source records attributed to Tomohiro Kinoshita.

At least 19 recordsLinked to original sources
PubMed2006

Prognostic significance of T-cell or cytotoxic molecules phenotype in classical Hodgkin's lymphoma: a clinicopathologic study.

PURPOSE: Classical Hodgkin's lymphoma (CHL) is characterized by Hodgkin's and Reed-Sternberg (H-RS) cells, most of which are derived from germinal-center B cells. Nevertheless, one or more markers for T cells and follicular dendritic cells (FDC) may be expressed in a minority of H-RS cells in some CHL patients, although the clinical significance of this remains controversial. The aim of this study was to clarify the association between phenotypic expression and clinical outcome in CHL. PATIENTS AND METHODS: Participants were 324 consecutive CHL patients, comprising 132 patients with nodular sclerosis (NS), 35 patients with NS grade 2 (NS2), and 157 patients with mixed cellularity (MC). We evaluated the presenting features and prognosis of patients on categorization into four phenotypically defined groups: B-cell (CD20+ and/or CD79a+; n = 63), T-cell and/or cytotoxic molecules (CD3+, CD4+, CD8+, CD45RO+, TIA-1+, and/or granzyme B+; n = 27), FDC (CD21+ without B-cell marker; n = 22), and null-cell types (n = 212). Other potential prognostic factors were examined. RESULTS: The T-cell and/or cytotoxic molecules group showed a significantly poorer prognosis than the other three groups (P < .0001). This finding was seen consistently in multivariate analyses. Morphologic subtyping (NS/NS2/MC) and Epstein-Barr virus positivity were not identified as independent prognostic factors. CONCLUSION: The presence of T-cell and/or cytotoxic antigens in H-RS cells may represent a poor prognostic factor in CHL, even if their expression is not regarded as lineage specific. Examination of T-cell and/or cytotoxic molecules phenotype in CHL patients is recommended as a routine pathologic practice.

Adolescent↗
PubMed2006

Disseminated intravascular coagulation in acute leukemia: clinical and laboratory features at presentation.

BACKGROUND: Although there are two major scoring systems for the clinical diagnosis of disseminated intravascular coagulation (DIC), the validity of these systems for leukemia-associated DIC remains to be confirmed. METHODS: By analyzing 125 newly diagnosed acute leukemia patients, we investigated clinical and laboratory features of leukemia-associated DIC, and determined the validity of the two established criteria. RESULTS: A total of 36 patients (29%) were diagnosed with DIC according to expert opinion, a method regarded as the de facto gold standard. Leukemia-associated DIC is characterized by rare manifestation of organ failure because of thrombosis and no relevance of the platelet count for the diagnosis. The results of receiver operating characteristics analysis favored fibrin degradation product (FDP) rather than D-dimer as the fibrin-related marker test. Although prothrombin time, plasma fibrinogen, and serum FDP levels were significantly different for patients with and without DIC, multivariate analysis identified FDP levels to be the only factor associated with DIC diagnosis. The cut-off level of 15 microg/mL for FDP was found to be the most effective to differentiate DIC from non-DIC, resulting in diagnostic sensitivity and specificity of 92% and 96%, respectively. The diagnostic results for our patients produced with this FDP-based system were at least comparable with or superior to those obtained with the two currently available scoring systems. CONCLUSIONS: Our findings suggest that an FDP-based criterion may be applicable for the diagnosis of leukemia-associated DIC. Although it appears to be simple and practicable enough for clinical use, prospective validation of this criterion is needed.

Acute Disease↗
PubMed2006

Aberrant DNA demethylation in promoter region and aberrant expression of mRNA of PAX4 gene in hematologic malignancies.

The PAX4 gene, a member of the paired box (PAX) gene family, is thought to be involved in regulating the fate of beta-cells in the mammalian pancreas. We observed the aberrant expression of PAX4 mRNA in 10 of 15 hematologic cell lines analyzed by RT-PCR. The restoration of PAX4 gene expression after treatment with the demethylating agent 5-aza-2'-deoxycitidine, as well as bisulfite sequencing analysis, indicated that gene overexpression was caused by DNA demethylation at the promoter region. Such DNA demethylation also was observed in primary lymphoma (20 out of 45 patients) on combined bisulfite restriction assay (COBRA). Forced expression of the PAX4 gene in the HEK293 and SHSY/610 cell lines conferred positive effects on cell growth. This profile of PAX4 thus corresponds to that of a candidate oncogene in hematologic malignancies.

Azacitidine↗
PubMed2006

Randomized phase II study of concurrent and sequential rituximab and CHOP chemotherapy in untreated indolent B-cell lymphoma.

CHOP combined with rituximab (R-CHOP) is regarded as one of the most effective treatments for indolent B-cell non-Hodgkin lymphoma (B-NHL), however, its optimal combination schedule remains unknown. We performed a randomized phase II study to explore a more promising schedule in untreated, advanced indolent B-NHL. Patients were randomized to receive either six courses of CHOP concurrently with rituximab (Arm C), or six courses of CHOP followed by six courses of weekly rituximab (Arm S). A total of 69 patients received the concurrent (n=34) or sequential (n=35) regimen. Overall response rate (ORR) in Arm C was 94% (95% confidence interval [CI], 79 to 99), including a 66% complete response (CR) compared with 97% (95% CI, 85-100), including a 68% CR in Arm S. Patients in Arm C experienced more grade 4 neutropenia (85%versus 70%) and experienced more grade 3 or greater non-hematological toxicities (21%versus 12%). Both arms were tolerated well. With a median follow-up of 28.2 months, the median progression-free survival (PFS) time was 34.2 months in Arm C, and was not reached in Arm S. R-CHOP is highly effective in untreated indolent B-NHL, either concurrent or in a sequential combination. Both combination schedules deserve further investigation.

Adult↗
PubMed2006

Loss of O6-methylguanine-DNA methyltransferase protein expression is a favorable prognostic marker in diffuse large B-cell lymphoma.

Although aberrant promoter hypermethylation of O6-methylguanine-DNA methyltransferase (MGMT) is a favorable prognostic marker in patients with diffuse large B-cell lymphoma (DLBCL), MGMT protein expression has not been thoroughly examined. The aim of this study was to evaluate the clinical implication of MGMT protein expression and its correlation with promoter hypermethylation of the gene. We investigated MGMT protein expression by immunohistochemical analysis of 63 DLBCL patients who received cyclophosphamide as part of multidrug regimens. In addition, promoter methylation of the MGMT gene was analyzed by a methylation-specific polymerase chain reaction assay, and correlations with chemotherapeutic effect and prognosis were statistically evaluated. Immunohistochemical assay results for MGMT protein were negative in 30.2% of patients with newly diagnosed DLBCL. Immunostaining results were closely correlated with the methylation status of the promoter. Promoter DNA methylation of the gene was not detected in 34 (81.0%) of 42 tumor samples determined to be MGMT-positive DLBCL by immunostaining and was detected in 15 (88.2%) of 17 cases of MGMT-negative DLBCL. Overall survival (OS) and disease-free survival (DFS) rates were significantly higher in MGMT-negative patients than in MGMT-positive patients (5-year OS, 81.3% versus 56.6% [P = .0375]; 5-year DFS, 66.3% versus 39.9% [P = .0121]). The combined rate for complete response (CR) plus unconfirmed CR was significantly higher in MGMT-negative patients (15/19, 79.0%) than in MGMT-positive patients (25/44, 56.8%) (P = .0488). A multivariate analysis showed that absence of MGMT expression was an independent prognostic factor for OS (relative risk, 4.09; P = .0258). Lack of MGMT protein expression is associated with aberrant promoter DNA methylation and appears to be a useful marker for predicting the survival of DLBCL patients.

Adult↗
PubMed2006

Promoter hypermethylation of the DNA-repair gene O6-methylguanine-DNA methyltransferase and p53 mutation in diffuse large B-cell lymphoma.

The gene for the DNA-repair enzyme O6-methylguanine-DNA methyltransferase (MGMT), which is closely related with cellular sensitivity to alkylating agents, is inactivated by promoter hypermethylation in several human cancers, including malignant lymphoma. Promoter hypermethylation of the MGMT gene is a favorable prognostic factor in diffuse large B-cell lymphoma (DLBCL). Although inactivation of the MGMT gene is closely related to p53 gene mutations in several cancers, the relationship between p53 gene mutation and MGMT inactivation in malignant lymphoma has not been thoroughly examined. We studied the correlation between MGMT hypermethylation and p53 mutation in DLBCL and their impacts on patient prognosis. In a retrospective cohort study, we used a methylation-specific polymerase chain reaction technique to analyze the methylation status of the promoter region of the MGMT gene in 116 DLBCL patients who received cyclophosphamide as part of multidrug combination chemotherapies. Denaturing high-performance liquid chromatography and direct sequencing were used to search for p53 gene mutations in exons 5 through 9 in 96 of the 116 samples. Disease-free survival and overall survival were estimated by the Kaplan-Meier method. Multivariate survival analyses were performed with the Cox proportional hazards model. Forty-five (38.8%) of 116 DLBCL patients showed MGMT promoter hypermethylation. The presence of MGMT hypermethylation was associated with better overall survival (P = .036). MGMT promoter hypermethylation was a prognostic factor that was independent of established prognostic factors, such as age, disease stage, serum lactic dehydrogenase level, and the number of extranodal disease sites (hazard ratio, 2.43; 95% confidence interval, 1.28-4.61; P = .007). p53 mutations were detected in 19 (19.8%) of 96 patients and were identified as a risk factor in the complete remission rate and overall survival (P = .0040, and P = .027, respectively). A correlation between MGMT hypermethylation and p53 mutation or p53 G:C-to-A:T mutation was not observed (P = .88, and P = .31, respectively). MGMT promoter hypermethylation and p53 mutation are useful prognostic markers in DLBCL. The impact of MGMT inactivation on p53 mutation in DLBCL is unclear.

Adult↗
PubMed2006

Increased oxidative DNA products in patients with acute promyelocytic leukemia during arsenic therapy.

Arsenic trioxide (ATO) has been used to treat acute promyelocytic leukemia (APL), but the oxidative DNA damage occurring in patients has not been fully elucidated. We measured 8-hydroxy-2'-deoxyguanosine (8-OHdG), one of the most abundant oxidative products of DNA, by enzyme-linked immunoassay, and reactive oxidative species (ROS), by luminol- and luminol-H2O2 chemiluminescence, in the plasma of four APL patients treated with ATO. After six courses of ATO therapy, the plasma 8-OHdG concentration had increased from 45.6+/-22.8 ng/mL to 310.2+/-239.6 ng/mL. The plasma chemiluminescence level did not change significantly. These findings suggest that ATO generates intracellular oxidative DNA damage, but this is not correlated with the plasma ROS level. The clinical significance of 8-OHdG during and after ATO therapy warrants further study.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2005

Clinical characteristics and prognostic implications of NPM1 mutations in acute myeloid leukemia.

Recently, somatic mutations of the nucleophosmin gene (NPM1), which alter the subcellular localization of the product, have been reported in acute myeloid leukemia (AML). We analyzed the clinical significance of NPM1 mutations in comparison with cytogenetics, FLT3, NRAS, and TP53 mutations, and a partial tandem duplication of the MLL gene (MLL-TD) in 257 patients with AML. We found NPM1 mutations, including 4 novel sequence variants, in 64 of 257 (24.9%) patients. NPM1 mutations were associated with normal karyotype and with internal tandem duplication (ITD) and D835 mutations in FLT3, but not with other mutations. In 190 patients without the M3 French-American-British (FAB) subtype who were treated with the protocol of the Japan Adult Leukemia Study Group, multivariate analyses showed that the NPM1 mutation was a favorable factor for achieving complete remission but was associated with a high relapse rate. Sequential analysis using 39 paired samples obtained at diagnosis and relapse showed that NPM1 mutations were lost at relapse in 2 of the 17 patients who had NPM1 mutations at diagnosis. These results suggest that the NPM1 mutation is not necessarily an early event during leukemogenesis or that leukemia clones with NPM1 mutations are sensitive to chemotherapy.

Adolescent↗
PubMed2005

Transcriptional regulation of FKLF-2 (KLF13) gene in erythroid cells.

FKLF-2 (KLF13) was cloned from fetal globin-expressing tissues and has been shown to be abundantly expressed in erythroid cells. In this study we examined the transcriptional regulation of the KLF13 gene. A 5.5 kb 5' flanking region cloned from mouse erythroleukemia (MEL) cell genomic DNA showed that major cis regulatory activities exist in the 550 bp sequence to the unique transcription start site, and that the promoter is more active in K562 cells than in COS-7 cells. The promoter was trans-activated by co-expressed GATA-1 through the sequence containing two CCAAT motifs, suggesting that GATA-1 is involved in the abundant expression of KLF13 mRNA in the erythroid tissue. Dual action, i.e. activating effect in COS-7 and repressive effect in K562 cell, was observed on its own promoter, suggesting a feedback mechanism for the transcriptional control of the KLF13 gene in the erythroid environment. These findings provide an insight on the mechanism of inducible mRNA expression of the KLF13 gene in erythroid cells.

Animals↗
PubMed2005

Long-term outcomes for unselected patients with acute myeloid leukemia categorized according to the World Health Organization classification: a single-center experience.

The actual utility of a new classification system of acute myeloid leukemia (AML) recently introduced by the World Health Organization (WHO) has not been thoroughly investigated yet. In this study, we evaluated long-term outcomes of unselected AML patients categorized according to the new WHO classification. Between 1990 and 2002, 109 adult AML cases were referred to our hospital. For the entire population, the median survival duration was 1.2 yr with a 5-yr survival rate of 31%. AML with recurrent genetic abnormalities accounted for 26%, AML with multilineage dysplasia for 29%, therapy-related AML for 13%, and AML not otherwise categorized for 32% of classifiable cases. Among the four groups, a significant difference was observed in terms of overall survival (P < 0.0001). Univariate analysis showed that six variables affected survival: cytogenetic risk, age, multilineage dysplasia, prior chemo/radiotherapy, type of treatment (intensive or palliative), and transplantation. However, in multivariate analysis no adverse prognostic impact of multilineage dysplasia and prior chemo/radiotherapy was detected (P = 0.4979 and 0.8702), whereas cytogenetic risk and patient age maintained their prognostic value (P = 0.0005 and 0.0100). These results indicate that outcomes for AML patients appear to be distinguished on the basis of the WHO classification, but the prognostic significance of multilineage dysplasia and prior therapy is lost after adjusting for cytogenetic risk and age. Our findings suggest that the WHO classification may be strengthened by greater emphasis on genetic/cytogenetic information.

Adolescent↗
PubMed2004

Epigenetic inactivation of tumor suppressor genes in hematologic malignancies.

A number of genetic alterations are involved in the development of hematologic malignancies. These alterations include the activation of oncogenes by chromosomal translocation or gene amplification and the inactivation of tumor suppressor genes by gene deletion or mutations. Recently, epigenetic change has been proven to be another important means of inactivating tumor suppressor genes in tumor cells, and hypermethylation of promoter DNA is one of the most important mechanisms. In hematologic malignancies, many kinds of tumor suppressor genes and candidate suppressor genes are epigenetically inactivated. Inactivation of tumor suppressor genes usually occurs in a disease-specific manner and plays important roles in the development and progression of the disease. Some of these alterations have clinical effects on treatment results or the prognoses of the patients.

Animals↗
PubMed2004

A randomized controlled trial investigating the survival benefit of dose-intensified multidrug combination chemotherapy (LSG9) for intermediate- or high-grade non-Hodgkin's lymphoma: Japan Clinical Oncology Group Study 9002.

The effect of enhancing the dose intensity (DI) of the key drugs in multidrug combination chemotherapy for malignant lymphoma is uncertain. We investigated the survival benefit of dose-intensified multidrug combination chemotherapy for intermediate- or high-grade non-Hodgkin's lymphoma (NHL). Patients without any prior chemotherapy were randomly assigned either to dose-intensified multidrug combination chemotherapy, LSG9 (VEPA-B/FEPP-AB/M-FEPA, treated 3 times every 10 weeks for 28 weeks total), or to control-arm combination chemotherapy, mLSG4 (VEPA-B/FEPP-B/M-FEPA, treated 4 times every 14 weeks for 54 weeks total). The planned DI of doxorubicin and cyclophosphamide were 1.96 and 1.47 times higher, respectively, in LSG9 than in mLSG4. Overall survival, complete response (CR) rate, and toxicities were evaluated. The 447 patients (230 for LSG9 and 217 for mLSG4) were enrolled between February 1991 and March 1995. The 5-year overall survival rates were 56.8% for LSG9 patients and 55.1% for mLSG4 patients (log-rank P = .42). The rates for CR plus uncertain CR were 70.0% for LSG9 and 64.5% for mLSG4. The toxicities of both regimens were similar and tolerable. The median actual DI of doxorubicin and cyclophosphamide were 1.56 and 1.17 times higher, respectively, in LSG9 than in mLSG4. Compared with the control regimen mLSG4, the dose-intensified regimen LSG9 did not show significant survival benefit. An increase in the DI of doxorubicin in multidrug combination chemotherapy did not improve the survival of patients with intermediate- or high-grade NHL.

Adolescent↗
PubMed2003

Case of Epstein-Barr virus-associated transformation of mantle cell lymphoma.

We report here a case of mantle cell lymphoma (MCL) in a patient who, following Epstein-Barr virus (EBV) infection, developed diffuse large B-cell lymphoma (DLBCL). A 47-year-old woman was diagnosed as having MCL with clinical stage IIIA in July 1990. After treatment with a third-generation chemotherapy without response, she was kept under observation for 8 years. In January 1999, fever and night sweats appeared with laboratory evidence for EBV infection, and acute swelling of lymph nodes and hepatosplenomegaly developed in May 1999. Histopathological examination confirmed the diagnosis of DLBCL. Sequence analysis of the complementarity-determining region (CDR)-III of the immunoglobulin heavy chain gene demonstrated clonal identity between the initial MCL and the subsequent DLBCL. Immunohistochemistry revealed that cyclin D1, CD5, and CD20 were expressed in the MCL but lost in the DLBCL cells, and EBER-ISH confirmed that EBV infection was absent in the former but present in the latter. Southern hybridization with the EBV terminal repeat probe showed a clear monoclonal pattern in the DLBCL specimen. All these results suggest that EBV infection may have been the molecular event that caused transformation of MCL cell(s) to DLBCL in this case. This is, to the best of our knowledge, the first well-documented case of EBV-associated transformation of MCL.

Antigens, CD↗
PubMed2003

Mutations and aberrant DNA methylation of the PROX1 gene in hematologic malignancies.

The homeobox gene PROX1 is related to the Drosophila prospero gene, which is expressed in the developing central nervous system and lens-secreting cone cells. We found that the PROX1 gene had missense and nonsense mutations in 4 of 29 hematologic cell lines analyzed. Decreased mRNA expression was also observed in half of these cell lines by RT-PCR. The restoration of PROX1 gene expression after treatment with the demethylating agent 5-aza-2'-deoxycytidine, as well as bisulfite sequencing analysis, indicated that gene silencing is caused by DNA hypermethylation at intron 1. Such hypermethylation was also seen in primary lymphomas (56.3%, 18/32) in a tumor-specific manner. These findings indicate that the profile of the PROX1 gene corresponds to that of a candidate tumor-suppressor gene.

Azacitidine↗
PubMed2002

Aberrant DNA methylation of p57(KIP2) gene in the promoter region in lymphoid malignancies of B-cell phenotype.

The cyclin-dependent kinase inhibitor p57(KIP2) is thought to be a potential tumor suppressor gene (TSG). The present study examines this possibility. We found that the expression of p57(KIP2) gene is absent in various hematological cell lines. Exposing cell lines to the DNA demethylating agent 5-aza-2'-deoxycytidine restored p57(KIP2) gene expression. Bisulfite sequencing analysis of its promoter region showed that p57(KIP2) DNA was completely methylated in cell lines that did not express the p57(KIP2) gene. Thus, DNA methylation of its promoter might lead to inactivation of the p57(KIP2) gene. DNA methylation of this region is thought to be an aberrant alteration, since DNA was not methylated in normal peripheral blood mononuclear cells or in reactive lymphadenitis. Methylation-specific polymerase chain reaction analysis found frequent DNA methylation of the p57(KIP2) gene in primary diffuse large B-cell lymphoma (54.9%) and in follicular lymphoma (44.0%), but methylation was infrequent in myelodysplastic syndrome and adult T-cell leukemia (3.0% and 2.0%, respectively). These findings directly indicate that the profile of the p57(KIP2) gene corresponds to that of a TSG.

Cyclin-Dependent Kinase Inhibitor p57↗
PubMed2002

The MAGE-A1 gene expression is not determined solely by methylation status of the promoter region in hematological malignancies.

Tumor antigens such as MAGE-A1 are aberrantly expressed in many human tumors and could be recognized by CTL. Thus, they could be targets for cancer immunotherapy. It is presently considered that the expression of the MAGE-A1 gene is regulated by methylation of its promoter region. To estimate the possibility of activating the MAGE-A1 gene with demethylating agents with a view toward clinical use, we assessed the methylation status of its CpG-rich promoter by sodium bisulfite mapping both of samples that express the gene and those that do not. Cell lines and samples from patients with hematological malignancies were examined. Surprisingly, the methylation status of the MAGE-A1 gene did not clearly correlate with the expression of the gene. Our results indicate that the MAGE-A1 gene expression is not determined solely by the methylation status of the promoter region in hematological malignancies.

Antigens, Neoplasm↗