Biomedical subjects

Yoshihiko Hoshida

Publications and source records attributed to Yoshihiko Hoshida.

44 records · Page 3Linked to original sources

PubMed2003

Methylation of promoter region in p27 gene plays a role in the development of lymphoid malignancies.

p27 belong to the cyclin-dependent kinase inhibitor family and plays an important role in regulation of cell cycle progression. Expression of these genes is epigenetically suppressed by methylation of their promoter regions. In this study, we examined protein expression and methylation status of the promoter region of p27 in 70 cases with non-Hodgkin's lymphoma and their relationship with proliferative activity of the tumor cells as revealed by Ki-67 index. There were 35 cases of B-cell, 11 of T-cell, 23 of NK/T-cell lymphoma, and 1 undetermined type. Immunohistochemically the loss of p27 protein expression was observed in 24 (69%) of 35 cases. Significant inverse correlation between p27 protein expression and Ki-67 index was found. Single strand conformation polymorphism (SSCP) followed by sequencing could not detect point mutations in any of the 68 cases. Bisulfite sequencing analysis showed that methylation of the promoter region of p27 were observed in 17 (25%) of 68 cases, in that several specific CpG sites around the start codon of p27 gene were preferentially methylated. Eight of 22 cases with loss of p27 protein expression showed methylation in CpG island of 5' region of p27 gene. These findings suggested that gene methylation plays a role in loss of expression of p27, which gives the cells proliferative advantages.

Adult↗

PubMed2002

Pyothorax-associated lymphoma: a review of 106 cases.

PURPOSE: Pyothorax-associated lymphoma (PAL) is a non-Hodgkin's lymphoma developing in the pleural cavity after a long-standing history of pyothorax. Full details of PAL are provided here. PATIENTS AND METHODS: Clinical and pathologic findings were reviewed in 106 patients with PAL collected through a nationwide survey in Japan. RESULTS: Age of the patients with PAL was 46 to 82 years (median, 64 years), with a male/female ratio of 12.3:1. All patients had a 20- to 64-year (median, 37-year) history of pyothorax resulting from artificial pneumothorax for treatment of pulmonary tuberculosis (80%) or tuberculous pleuritis (17%). The most common symptoms on admission were chest and/or back pain (57%) and fever (43%). Laboratory data showed that the serum neuron-specific enolase level was occasionally elevated (3.55 to 168.7 ng/mL; median, 18.65 ng/mL), suggesting a possible diagnosis of small-cell lung cancer. Histologically, PAL usually showed a diffuse proliferation of large cells of B-cell type (88%). In situ hybridization study showed that PAL in 70% of the patients was Epstein-Barr virus (EBV)-positive. PAL was responsive to chemotherapy, but the overall prognosis was poor, with a 5-year survival of 21.6%. CONCLUSION: This study established the distinct nature of PAL as a disease entity. PAL is a non-Hodgkin's lymphoma of exclusively B-cell phenotype in the pleural cavity of patients with long-standing history of pyothorax, and is strongly associated with EBV infection. Development of PAL is closely related to antecedent chronic inflammatory condition; therefore, PAL should be defined as malignant lymphoma developing in chronic inflammation.

Aged↗

PubMed2002

Marked hyperbilirubinemia caused by acute cellular rejection combined with preservation injury in an infant undergoing living-related liver transplantation.

Acute cellular rejection (ACR) and preservation injury (PI) are major complications occurring early after liver transplantation (LTx) and sometimes lead to severe graft dysfunction. We herein report an infant who developed marked hyperbilirubinemia as a result of combined ACR and PI in addition to ischemic damage from bleeding, but recovered without re-LTx. In a 1-yr-old-girl undergoing living-related LTx, liver biopsy (LBx) on post-operative day 7 showed ballooning of the hepatocytes, i.e. microvesicular steatosis (30%) and occasional centrolobular necrosis, consistent with mild-to-moderate PI and ACR with a rejection activity index (RAI) of 2.0. Because drainage of an intra-abdominal abscess was performed and a systemic infection was considered severe, the tacrolimus level was decreased and steroids were discontinued. The total bilirubin level started to rise, thereafter, reaching a maximum of 47.6 mg/dL at 1 month after LTx. LBx showed an RAI of 6.0 and steatosis of 10%. With good response to an increase of tacrolimus level and administration of steroid, the total bilirubin level gradually decreased, finally reaching the normal range in 3 months, and LBx showed no steatosis or finding of ACR. From this experience, ACR, if combined with mild-to-moderate PI or other ischemic damage, may lead to severe clinical manifestations after LTx, which, however, could remit with conservative therapy and without re-LTx.

Acute Disease↗

PubMed2002

Gene mutations in lymphoproliferative disorders of T and NK/T cell phenotypes developing in renal transplant patients.

Post-transplantation lymphoproliferative disorder (PT-LPD) is characterized by lymphoid proliferation after organ or bone marrow transplantation. In Western countries, most cases of PT-LPD are B-cell-derived and Epstein-Barr virus-associated, in which alterations of c-myc, p53, and N-ras genes might play a role in disease progression. In Japan, PT-LPD of T- and NK/T-cell types are not uncommon in renal transplant patients. Mutations of p53 (exons 4 through 8), K-ras (exons 1 and 2), c-kit (exons 11 and 17), and beta-catenin genes (exon 3) in 12 cases of these diseases were analyzed by PCR single strand conformation polymorphism and then by direct sequencing. p53 gene mutations were detected in 5 of 5 cases of peripheral T-cell lymphoma, 3 (60%) of 5 cases of adult T-cell leukemia/lymphoma, and 1 of 2 cases of NK/T cell lymphoma. Twenty-five percent of T and NK/T cell lymphomas showed K-ras mutations. Mutations of c-kit and beta-catenin genes were found in 33% of cases. Among a total of 42 substitution mutations, 40 were transitions with involvement of CpG sites in 20 to 30% of cases. Most cases had at least one mutation that changed an amino acid, which might have provided the selection pressure for expansion. These findings suggested that p53 gene mutations might play a central role in development of peripheral T-cell lymphoma including adult T-cell leukemia/lymphoma in renal transplant patients.

Adolescent↗

PubMed2002

VCP (p97) regulates NFkappaB signaling pathway, which is important for metastasis of osteosarcoma cell line.

In order to identify genes associated with metastasis, suppression subtractive hybridization (SSH) was performed using murine osteosarcoma cell line Dunn and its subline with higher metastatic potential, LM8. SSH revealed expression of the gene encoding valosin-containing protein (VCP; also known as p97) to be constitutively activated in LM8 cells, but it declined in Dunn cells when the cells became confluent. Because VCP is known to be involved in the ubiquitination process of Inhibitor-kappaBalpha (IkappaBalpha), an inhibitor of nuclear factor-kappaB (NFkappaB), whether VCP influences NFkappaB activation or not was examined by using VCP-transfected Dunn cells (Dunn/VCPs). When stimulated with tumor necrosis factor-alpha (TNFalpha), Dunn/VCPs showed constantly activated NFkappaB, although in the original Dunn cells and control vector transfectant (Dunn/Dunn-c) NFkappaB activation ceased when the cells became confluent. Western immunoblot analysis showed an increase of phosphorylated IkappaBalpha (p-IkappaBalpha) in the cytoplasm of confluent Dunn/Dunn-c cells compared to that of Dunn/VCPs. Therefore, decrease of p-IkappaBalpha degrading activity might be responsible for the decrease in NFkappaB activation. In vitro apoptosis assay demonstrated increased apoptosis rates of Dunn/Dunn-c cells after TNFalpha stimulation compared to those of Dunn/VCPs and LM8 cells. In vivo metastasis assay showed increased incidences of metastatic events in Dunn/VCP-1 inoculated male C3H mice compared to those in Dunn/Dunn-c inoculated mice. These findings suggested that VCP expression plays an important role in the metastatic process. Anti-apoptotic potential in these cells owing to constant NFkappaB activation via efficient cytoplasmic p-IkappaBalpha degrading activity may explain the increased metastatic potential of these cells.

Adenosine Triphosphatases↗

PubMed2002

Polymerase chain reaction-based clonality analysis in thyroid lymphoma.

A previous patho-epidemiological study indicated that thyroid lymphoma (TL) evolves among active lymphoid cells into chronic lymphocytic thyroiditis (CLTH), a thyroid-specific autoimmune disease. In this study, clonality of B-cells in the CLTH and TL lesions was analyzed using polymerase chain reaction (PCR)-based method on surgically resected samples from 10 cases of TL; 7 mucosa-associated lymphoid tissue (MALT) lymphoma and 3 diffuse large B-cell lymphoma (DLBCL). CLTH lesions coexisted in all the cases with MALT lymphoma, but not in the three DLBCL cases. In cases of MALT lymphoma, the lymphomatous and CLTH areas were separately microdissected from each section and analyzed for clonality. In the cases of DLBCL, the whole specimens were used for clonality analysis. CLTH lesions showed smear in 6 samples, two bands in one, and more than three (oligoclonal pattern) in 2. MALT lymphoma lesions showed single or two bands (monoclonal pattern) in 4, oligoclonal pattern in 4, and smear in one. DLBCL showed monoclonal pattern in two and oligoclonal pattern in one. One common band was present among two separate MALT lesions in one case, but no common bands were found in the remaining six cases. These findings suggested the clonal evolution of B-cell from polyclonal to monoclonal proliferation to take place in the continuum of lymphoproliferative lesions into autoimmune thyroiditis.

Aged↗

PubMed2002

Clonality analysis of follicular lymphoma using laser capture microdissection method.

Whether a common and a single clone present, or not, among follicles of follicular lymphoma (FL) was examined in 12 cases with FL. Histologic grade was I in 6 cases, II in 3, and III in 3. DNA was selectively extracted from the neoplastic follicles of paraffin-embedded samples with use of laser capture microdissection method, and used for PCR-based analysis of rearrangement of immunoglobulin heavy chain variable region gene. Three different follicles in each case of FL were microdissected. Semi-nested PCR was performed using two sets of primers (Fr2A and Fr3A). In PCR with Fr2A primers, nine of 12 cases showed a common band among neoplastic follicles. The remaining three cases showed no PCR products. With Fr3A primers, eight of 12 cases showed a common band among follicles of the same case. The other four cases showed oligoclonal bands, among them presence of a common band was difficult to assess. Oligoclonal bands were more frequently observed in PCR with Fr3A than that with Fr2A and in grade I or II than in grade III cases. In total, 11 of 12 cases showed a common band in PCR with either Fr2A or Fr3A primers. In two cases, DNA extracted from whole section was amplified with both Fr2A and Fr3A or only Fr3A primers, showing smear or oligoclonal bands. These results showed the presence of a single clone of cells in neoplastic follicles of FL and the usefulness of PCR-based rearrangement analysis of immunoglobulin heavy chain gene combined with microdissection methods for differential diagnosis of FL from follicular hyperplasia.

Adult↗

PubMedDate not supplied

Reassessment of the 1993 Osaka grading system for localized soft tissue sarcoma in Japan.

BACKGROUND: The Osaka system for soft-tissue sarcoma grading was proposed through an analysis of soft-tissue sarcoma (STS), treated from 1964 to 1989. The present study was conducted to evaluate the utility of the Osaka system under recent therapeutic regimens. PATIENTS AND METHODS: One hundred and eleven patients with localized STSs arising in the trunk and extremities (66 males and 45 females; median age 57) were selected. Histological factors, argyrophilic nucleolar organizer region (AgNOR) count and Ki-67 labeling index (LI) were evaluated for prognostic significance. RESULTS: Univariate analysis revealed that histological classification, mitotic count, cellularity, AgNOR count, and Ki-67 LI were prognostically significant for survival. Multivariate analysis revealed Ki-67 LI as an independent prognostic factor. The five-year survival rate for low-, intermediate-, and high-grade STSs in Osaka grading was 94.6%, 75.2%, and 68.4%, respectively. CONCLUSION: Osaka grading is a useful system for the decision-making of therapeutic modalities for STS.

Adult↗