Biomedical subjects

Y Hatta

Publications and source records attributed to Y Hatta.

At least 19 recordsLinked to original sources

PubMed2005

WT1 expression level and clinical factors in multiple myeloma.

Although Wilm's Tuomor gene (WT1) was first identified as a tumor suppressor gene for Wilm's tumor, WT1 overexpression has been detected in different malignant cell types including leukemia. Increased expression of WT1 in acute leukemia is potentially used as a marker of minimal residual disease. However, the significance of the gene for multiple myeloma is still not clear. To determine the clinical relevance of WT1 expression in multiple myeloma, we examined the association of clinical parameters and WT1 expression in bone marrow for 17 newly diagnosed multiple myeloma patients. WT1 was assessed by real-time quantitative polymerase chain reaction (RQ-PCR) and calculated standardized WT1 expression level per 100 plasma cells in the bone marrow specimen as "corrected WT1". The expression of standardized WT1 and corrected WT1 in myeloma was 59 to 1,600 copies/microg RNA and 0.05 to 406.3 copies/microg RNA/100 plasma cells, respectively, lower than in leukemia. WT1 transcripts increased when clinical factors worsen, including the stage, amount of M protein, Hb, platelet count, blood urea nitrogen (BUN), creatinine, serum alkaline phosphatase (ALP), calcium, beta2-microglobulin, thymidine kinase activity (TK), and C-reactive protein (CRP). In conclusion, the expression level of WT1 could be an additional marker to the standard parameters considered in risk assessment for multiple myeloma.

Biomarkers, Tumor↗

PubMed2003

Proton-number fluctuation as a signal of the QCD critical end point.

We argue that the event-by-event fluctuation of the proton number is a meaningful and promising observable for the purpose of detecting the QCD critical end point in heavy-ion collision experiments. The long range fluctuation of the order parameter induces a characteristic correlation between protons which can be measured. The proton fluctuation also manifests itself as anomalous enhancement of charge fluctuations near the end point, which might be already seen in existing data.

Journal Article↗

PubMed2002

Role of tumor suppressor genes in the development of adult T cell leukemia/lymphoma (ATLL).

Adult T cell leukemia/lymphoma (ATLL) is one of the peripheral T cell malignant neoplasms strongly associated with human T cell leukemia virus type-I (HTLV-I). Although the viral transactivating protein Tax has been proposed to play a critical role in leukemogeneis as shown by its transforming activity in various experimental systems, additional cellular events are required for the development of ATLL. One of the genetic events in ATLL is inactivation of tumor suppressor genes. Among many candidates for tumor suppressor genes, the main genetic events have been reported to center around the cyclin-dependent kinase inhibitors ((CDKIs) p15INK4A, p16INK4B, p18INK4C, p19INK4D, p21WAF1, p27KIP1, and p57KIP2), p53 and Rb genes; all of them play a major regulatory role during G1 to S transition in the cell cycle. Acute/lymphomatous ATLL has frequent alterations of p15 (20%) and p16 (28-67%), while chronic/smoldering ATLL has fewer abnormalities of p15 (0-13%) and p16 (5-26%). Most of these changes are deletion of the genes; fewer samples have mutations. ATLL patients with deleted p15 and/or p16 genes have significantly shorter survival than those individuals with both genes preserved. Although genetic alterations of p18, p19, p21, p27 have rarely been reported, inactivation of these genes may contribute to the development of ATLL because low expression levels of these genes seem to mark ATLL. The p53 gene is mutated in 10-50% of acute/lymphomatous ATLL. Functional impairment of the p53 protein, even if the gene has wild-type sequences, has been suggested in HTLV-I infected cells. Each of these genetic events are mainly found in acute/lymphomatous ATLL, suggesting that alterations of these genes may be associated with transformation to an aggressive phenotype. The Rb tumor suppressor gene is infrequently structurally altered, but one half of ATLL cases have lost expression of this key protein. Notably, alterations of one of the CDKIs, p53 and Rb genes appear to obviate the need for inactivation of other genes in the same pathway. A novel tumor suppressor gene on chromosome 6q may also have a critical role in the pathogenesis of ATLL. Taken together, tumor suppressor genes are frequently altered in acute/lymphomatous ATLL and their alteration is probably the driving force fueling the transition from chronic/smoldering to acute/lymphomatous ATLL.

Adult↗

PubMed2001

Leukaemia inhibitory factor and interleukin 6 inhibit secretion of prolactin and growth hormone by rat pituitary MtT/SM cells.

The rat pituitary cell line, MtT/SM, has the characteristics of somatomammotrophs. The cells secrete both prolactin (PRL) and growth hormone (GH). We examined the effects of cytokines such as leukaemia inhibitory factor (LIF), interleukin 6 (IL-6), oncostatin M and interleukin 11 on the secretion of these hormones by the cells. These cytokines stimulate proliferation of the cells and inhibit the secretion of PRL by 70-80% and that of GH by 50%. They induce tyrosine phosphorylation of STAT3 in the cells. The cells containing PRL or GH decreased at 48 h after treatment of the cells with LIF or IL-6. These results suggest that the LIF/IL-6 family of cytokines inhibits the functions of mammotrophs and somatotrophs in the pituitary gland.

Animals↗

PubMed2001

Analysis of 20-year follow-up study of LVP regimen for adult acute lymphoblastic leukemia.

In an attempt to develop a new intensive chemotherapy for adults with untreated acute lymphoblastic leukemia (ALL), 3 sequential programs were designed for 62 patients (age range, 15 to 74 years; median age, 32 years) consisting of the LVP-79 (1979-1984, 27 patients), LVP-85 (1984-1986, 14 patients), and LVP-87 (1987-1989, 21 patients) regimens. The influence of clinical and biologic characteristics on the patient outcome was also examined. L-asparaginase (L-asp), vincristine, and prednisolone, defined collectively as LVP, were administered for induction chemotherapy in all protocols. After achieving complete remission (CR), patients underwent 2 years of multi-agent consolidation, intensification, and maintenance therapy consisting of various combinations. No significant differences were noted between the 3 groups regarding CR rate or survival. In total, 47 of 62 patients (75.8%) achieved CR. The median overall survival (OS) and median CR durations were 550 days and 341 days, respectively. Overall, the estimated survival rate at 20 years was 18.1%. The disease-free survival rate at 20 years was 26.2%. According to univariate analysis, the most favorable pretreatment characteristic for achieving CR was age. A younger age (<40 years of age), platelet count >30 x 10(9)/L, having L1 morphology (French-American-British [FAB]classification subtype), female sex, and the absence of chromosomal abnormalities also helped improve survival rate. According to multivariate analysis, presence of Ph chromosome was found to be a major influencing factor for OS. Although higher doses of L-asp were administered than those used in previous studies, the adverse effect of L-asp was rarely identified. Therefore, it should be considered one of the key drugs for treatment of adult ALL. Further strategies still need to be developed to obtain better survival in adult ALL.

Adolescent↗

PubMed2001

Comparison of statistical power between 2 * 2 allele frequency and allele positivity tables in case-control studies of complex disease genes.

In case-control studies of complex disease genes, allele frequencies or allele positivities at candidate loci or markers are compared between cases and controls. Although 2 x 2 contingency tables based on allele frequency and allele positivity are generally used to perform simple statistical tests (e.g. a comparison of two proportions and a chi2 test), little is known about the difference in power between the two tables. In this study, we investigated the number of subjects required to obtain a power of 1-beta with a significance level of alpha for the allele frequency and allele positivity tables. A large difference in the required number of subjects was found between the two tables. Allele positivity tables were suitable for the detection of susceptibility alleles showing a dominant mode of inheritance (MOI). On the other hand, allele frequency tables were suitable for the identification of susceptibility alleles showing a recessive MOI or a multiplicative MOI. In the case of an additive MOI, a suitable table was determined by combining the frequency of the susceptibility allele and the penetrance. These results imply that there are cases in which true association is detected based on one contingency table and is not detected based on another. A simulation analysis revealed that the type I error rate was not much inflated under the null hypothesis of no association, even when a statistical test was performed twice using both allele frequency and allele positivity tables. In contrast, under the alternative hypothesis, the loss of power was marked when a test was performed once using an unsuitable table. In conclusion, statistical tests should be performed using both tables, without adjustment of multiplicity, in case-control studies of complex disease genes when the study objective is exploratory.

Alleles↗

PubMed2000

Mutations of the E2F4 gene in hematological malignancies having microsatellite instability.

Mutations of coding repeats within the E2F4, TGF-betaRII, BAX, IGFIIR, and hMSH3 are critical targets of microsatellite instability (MSI) in many kinds of cancers. We analyzed 9 childhood acute lymphoblastic leukemia (ALL) samples, 5 acute myelocytic leukemia (AML) samples, and 10 adult T-cell leukemia (ATL) samples having MSI to determine whether they had mutations of the E2F4, TGF-betaRII, BAX, IGFIIR, and hMSH3 genes. Frameshift mutations were found at trinucleotide repeats within a coding exon of the E2F4 gene in 2 of 10 (20%) ATL samples and 1 of 9 (11%) childhood ALL samples. No mutations were found in the TGF-betaRII, BAX, IGFIIR, and hMSH3 genes. E2F4 is a transcription factor that influences the cell-cycle progression. These results suggest that mutations of the E2F4 gene, presumably caused by an abnormality of one of the DNA repair genes, may play an important role in development of ATL and childhood ALL. (Blood. 2000;95:1509-1510)

Adult↗

PubMed2000

[Analysis of pulmonary function in leukemia patients after bone marrow transplantation: effects of prior chemotherapy].

To evaluate the effects of prior chemotherapy on pulmonary function after bone marrow transplantation(BMT), pulmonary function tests were performed prior to and after BMT on 7 acute leukemia (AL) and 13 chronic myelogenous leukemia (CML) patients given with CY (60 mg/kg x 2 days), total body irradiation (3 Gy x 4 days, 10 cGy/min), and CyA plus short-term MTX. No patient had graft-versus-host disease or lung complications. Pulmonary function after BMT did not deteriorate in the AL patients; however, both %Vital Capacity(%VC) and DL/VA decreased significantly in the CML patients (%VC before BMT: 112.1 +/- 11.5%, after BMT: 93.7 +/- 9.4%; DL/VA before BMT: 79.2 +/- 14.6%, after BMT: 54.1 +/- 10.6%). Although prior regimens of busulfan (BU) or interferon (IFN) were equal risk factors for decreased %VC after BMT, decreases in DV/VA were more significant in CML patients who received IFN. CML patients, especially those who have received BU or IFN, should be carefully monitored for pulmonary function to prevent respiratory failure after BMT.

Acute Disease↗

PubMed2000

[Evaluation of hematopoiesis by granulocyte elastase after hematopoietic stem cell transplantation].

To evaluate hematopoietic restoration after hematopoietic stem cell transplantation (HSCT), we sequentially monitored the post-HSCT level of granulocyte elastase (GE), a sensitive parameter of qualitative and quantitative changes in granulopoiesis. We compared it with routinely used hematopoietic recovery indices, such as leukocyte and reticulocyte count. We also compared levels of GE in the clinical administration of different colony stimulating factors (granulocyte-colony stimulating factor (G-CSF) versus macrophage-colony stimulating factor (M-CSF) and in different types of hematopoietic stem cell transplantation (allogeneic bone marrow transplantation (BMT) versus autologus peripheral blood stem cell transplantation (PBSCT)). Days to first increase of GE after HSCT were 3.0 and 2.3 days earlier than increase of leukocytes in allo-BMT and auto-PBSCT, respectively. Recovery of highly fluorescent reticulocytes and monocytes were later than recovery of GE. These results indicated that granulopoiesis after transplantation started before the increase in peripheral leucocyte count, and that GE was the earliest indicator of hematopoietic recovery. On the basis of GE level, M-CSF had the same stimulating effect on granulopoiesis as G-CSF. The nadir of GE in PBSCT was significantly higher than that in BMT, indicating continuous granulopoiesis in PBSCT. From these results, we concluded that measurements of GE can be used for the clinical evaluation of myelosuppression by different conditioning regimens as well as of granulopoiesis induced by various cytokines.

Adolescent↗

PubMed1999

Detailed deletion mapping of the long arm of chromosome 6 in adult T-cell leukemia.

Previously, we have found that the loss of heterozygosity (LOH) was frequently observed on chromosome 6q in acute/lymphoma-type adult T-cell leukemia (ATL), suggesting a putative tumor-suppressor gene for ATL may be present on chromosome 6q. To further define a region containing this gene, we performed fine-scale deletional mapping of chromosome 6q in 22 acute/lymphomatous ATL samples using 24 highly informative microsatellite markers. LOH was found in 9 samples (40. 9%) at 1 or more of the loci examined. Of the 9 samples, 8 shared the same smallest commonly deleted region flanked by D6S1652 and D6S1644 (6q15-21). The genetic distance between these two loci is approximately 4 cM. These results suggest that a putative tumor-suppressor gene on chromosome 6q15-21 probably plays a very important role in the evolution of acute/lymphomatous ATL. Our map provides key information toward cloning the gene.

Chromosome Mapping↗

PubMed1999

Identification of the gene variations in human CD22.

CD22, a member of the immunoglobulin superfamily, is a B-cell transmembrane glycoprotein that acts as an accessory-signaling component of the B-cell antigen receptor (BCR). Recent evidence indicating the role of CD22 as a negative regulator of BCR signal transduction prompted us to test the possibility that genetic variations of human CD22 may be associated with autoimmune diseases. In this study, variation screening of the entire CD22 coding region was performed, and possible association with rheumatic diseases was tested, using the genomic DNA from 207 healthy Japanese individuals, 68 patients with systemic lupus erythematosus (SLE), and 119 patients with rheumatoid arthritis (RA). Through the variation screening, seven non-synonymous and four synonymous substitutions were identified. In addition, single base substitutions were found in two introns flanking exon-intron junctions. Among these variations, Q152E substitution within the second extracellular domain was observed with a marginally higher frequency in the patients with SLE (3/68, 4.4%) than that in healthy individuals (1/207, 0.5%) (P=0.048. SLE vs healthy individuals), although this difference was no longer significant after correction for the number of comparisons (Pc=0.62). No significant association was observed between any of the variations and RA. These findings indicate that a number of genetic variants are present in CD22, and suggest that CD22 could be considered a candidate for the susceptibility genes to autoimmune diseases.

Adolescent↗

PubMed1999

Association of Fc gamma receptor IIIB, but not of Fc gamma receptor IIA and IIIA polymorphisms with systemic lupus erythematosus in Japanese.

Human Fc gamma receptor (Fc gamma R) genes form a clustered gene family on chromosome 1q21-24. Although the association of Fc gamma R polymorphisms with systemic lupus erythematosus (SLE) has been extensively studied, the results are often contradictory. In this study, Fc gamma RIIA-131H/R, Fc gamma RIIIA-176F/V and Fc gamma RIIIB-NA1/2 genotypes were determined in the Japanese patients with SLE (n = 81) or rheumatoid arthritis (RA, n = 115) as well as in healthy individuals (n = 217), and possible association with the disease was tested using case-control analysis. Unlike in other populations, significant difference was not observed in the frequencies of Fc gamma RIIA and Fc gamma RIIIA genotypes between patients with SLE and healthy individuals. However, significant difference was detected in the frequencies of Fc gamma RIIIB genotypes between SLE and healthy individuals (P = 0.008). The odds ratio [OR] of the Fc gamma RIIIB-NA2/NA2 homozygotes for the development of SLE was 2.52 (95% confidence interval [CI]: 1.33-4.79). Among the patients with SLE, individuals with NA2/2 were significantly more likely to have lupus nephritis (P = 0.007). No association was observed between any of the Fc gamma R polymorphisms and RA. Significant linkage disequilibrium was detected between Fc gamma RIIIA and IIIB, but neither between IIA and IIIA, nor between IIA and IIIB. These observations may underscore the relevance of defective immune complex handling in the pathogenesis of SLE, or may suggest the presence of primarily associated gene(s) in linkage disequilibrium with Fc gamma R genes.

Adolescent↗

PubMed1999

Possible association of human leucocyte antigen DR1 with delayed sleep phase syndrome.

The study investigated the human leucocyte antigen (HLA), types A, B and DR, of 42 patients with delayed sleep phase syndrome (DSPS) and compared the frequencies of the antigens with those in 117 healthy controls. The comparison revealed that the gene frequencies and positivities of HLA-A, -B and -DR, except for DR1, had no significant differences between the patients and controls. The frequency of HLA-DR1 was increased in the DSPS patients as compared with that in the healthy controls (P = 0.0069 in positivity). Although the corrected P-value (0.069) for multiple comparisons almost reached the significance level, the results indicated a possible association of the HLA-DR1 antigen with DSPS. This study suggests that there are genetic predispositions to DSPS.

Adolescent↗

PubMed1999

Ovarian cancer: loss of heterozygosity frequently occurs in the ATM gene, but structural alterations do not occur in this gene.

Ataxia-telangiectasia is a multisystem recessive disease characterized clinically by cerebellar ataxia, oculocutaneous telangiectasias, immunodeficiency, sensitivity to radiomimetic agents and an increased predisposition to cancer. This pleiotropic disorder is caused by mutations in the ATM gene, which is located at the human chromosomal region 11q23. Loss of heterozygosity (LOH) at 11q22-q23 is a frequent event in ovarian cancer, suggesting the presence of a tumor suppressor gene in this region. We have found that LOH in the ATM gene occurred in 44% of informative cases in a series of 22 primary ovarian tumors. LOH of this region occurred at the same frequency during the advanced stages (III-IV; 3/9, 33%) as in the early stages (I-II; 4/13, 31%) of ovarian cancer. To investigate the role of ATM in ovarian cancer, we used a PCR-based single-strand conformation polymorphism assay for mutation detection of the entire coding sequence of the ATM gene (65 exons) in 22 ovarian tumors. No somatic alterations of the ATM gene were found in these ovarian cancer samples including those with LOH present in the ATM gene. Our study has identified a region (11q23) which probably contains a frequently altered tumor suppressor gene in ovarian cancer, and this gene does not appear to involve the coding sequences of the ATM gene.

Adenocarcinoma↗

PubMed1999

HLA genes and haplotypes in Ryukyuans suggest recent gene flow to the Okinawa Islands.

Polymorphism of HLA genes was investigated in a population sample of Ryukyuans living on the main island of Okinawa (n = 197), in the southwestern islands of Japan. Serological typing was applied to class I loci (HLA-A, -B, and -C) and to HLA-DRB1; nucleotide sequence-level typing was performed using PCR microtiter plate hybridization and PCR single-strand conformation polymorphism methods. Ryukyuans showed a higher frequency of DRB1*0405 and lower frequencies of DRB1*1502 and DRB1*1302 compared with Hondo Japanese living on main islands. Principal components and phylogenetic analyses of 12 East Asian populations, including Ryukyuans, were performed based on the allele frequencies of HLA-A, -B, and -DRB1. In the principal components analysis 3 Japanese populations (Ryukyuans, Hondo Japanese, and Ainu) formed a cluster and showed the highest affinity to 2 Korean populations. In the phylogenetic tree Ryukyuans and Ainu were neighbors, but the genetic distance between them was larger than the distances between Ryukyuans and Hondo Japanese and between Ryukyuans and Korean populations. The geographic cline of the predominant haplotype in Ryukyuans, A*24-B*54-DRB1*0405, suggests that an ancestral population possessing A*24-B*54-DRB1*0405 moved into the Okinawa Islands after the divergence of Ryukyuans from the Ainu. Such a recent gene flow, probably from South China to the Okinawa Islands, is considered the major cause of difference in genetic characteristics between Ryukyuans and the Ainu.

Adult↗

PubMed1998

Allelotype analysis of adult T-cell leukemia.

Allelotype analysis of adult T-cell leukemia (ATL) was undertaken for the first time to identify chromosomal loci relevant to the development of acute/lymphomatous ATL. Loss of heterozygosity (LOH) was screened using 94 highly polymorphic microsatellite markers, distributed among all nonacrocentric, autosomal chromosomes. In each of the 22 cases, DNA obtained from their leukemic cells in acute/lymphomatous phase was compared with their constitutional DNA from mononuclear cells in chronic or remission phase. Allelic losses of at least on one chromosome arm occurred in 91% of the cases (20 individuals). Among 39 chromosome arms, allelic losses were observed on 31 arms at least for one sample. A high frequency of allelic loss (>30%) was seen on chromosome arms 6q (41%) and 17p (48%). The mean fractional allelic loss (FAL) was 0.109. These findings suggest that a novel tumor suppressor gene on chromosome arm 6q, as well as the p53 gene on chromosome arm 17p, probably have an important role in the development of acute/lymphomatous ATL.

Adult↗

PubMed1998

Microsatellite instability in adult T-cell leukaemia.

Microsatellite instability (MSI) is thought to represent a defect of the DNA mismatch repair system which has been implicated in the tumourigenesis of several human malignancies. We investigated MSI in acute/ lymphomatous adult T-cell leukaemia (ATL: n=22) using 54 highly polymorphic dinucleotide short-tandem repeat sequences. The corresponding control DNA from each individual was obtained from the peripheral blood in either chronic phase (n=5) or when complete remission was achieved (n=17). 10/22 (41%) patients had MSI, six of whom showed MSI in multiple loci; four loci had MSI in multiple samples. The incidence of MSI in ATL was found to be higher than in other haematological malignancies, indicating MSI as a feature of ATL, which may be involved in the progression of the disease.

Humans↗

PubMed1998

[Donor leukocyte transfusion as treatment for relapsed chronic myelogenous leukemia after allogeneic bone marrow transplantation].

Three patients with relapse (two molecular and one cytogenetic relapse) after allogeneic bone marrow transplantation (BMT) for chronic myelogenous leukemia (CML) were treated with donor leukocyte transfusion (DLT). Two had complete molecular remission, which persisted 16 and 20 months after treatment. The performance status of all patients was 90-100%. Mild chronic GVHD was observed in one patient as a side effect of DLT. One patient with cytogenetic relapse required three infusions to attain molecular remission and this suggests the importance of cell numbers to infuse in DLT. Positive anti-nuclear antibody was observed in the effective cases and elevation of IgE in all cases after DLT. These abnormal laboratory findings may suggest a relationship between GVHD and GVL. DLT may be effective therapy for patients with CML who relapse after BMT. Further controlled studies are necessary to determine the optimal number of cells to infuse, interval and frequency of DLT.

Adult↗