Publications by authors named "Koichi Ohshima"

Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related neoplasm preferentially involving the upper aerodigestive tract. Here we show that NK-cell-specific Trp53 disruption in mice leads to the development of NK-cell lymphomas after long latency, which involve not only the hematopoietic system but also the salivary glands. Before tumor onset, Trp53 knockout causes extensive gene expression changes, resulting in immature NK-cell expansion, exclusively in the salivary glands.

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Adult T-cell leukaemia/lymphoma (ATLL) is an aggressive peripheral T-cell neoplasm with a poor prognosis. T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is an immune checkpoint receptor expressed on T and natural killer cells. Although increased TIGIT expression in the tumour microenvironment is associated with poor prognosis in various neoplasms, its relevance in ATLL remains unknown.

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Background: Although recent studies have revealed the importance of inflammation in the pathogenesis of aortic dissection (AD), little is known about the relationships among inflammatory cells in human AD tissue.

Methods And Results: We assessed the relationships among various immune cell types, including neutrophils, macrophages (M1 and M2), B cells, and helper T cells (Th1, Th2, Th17, Treg and Tfh ) in human AD tissue. AD tissues displayed abundant infiltration of immune cells.

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Article Synopsis
  • - Romidepsin is a promising treatment for patients with peripheral T-cell lymphoma (PTCL), but its timing in therapy remains debated; this study aimed to assess its safety and effectiveness after GDP therapy.
  • - Conducted from March 2019 to March 2021, the study involved 7 patients with relapsed/refractory PTCL and found a 2-year overall survival rate of 71% and a 57% overall response rate after treatment.
  • - Although common side effects included neutropenia, which was manageable, no treatment-related deaths occurred, suggesting that the GDP plus romidepsin regimen may be a safe option for older patients not eligible for transplants; however, further research is necessary.
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We present a case of an angioimmunoblastic T-cell lymphoma (AITL) and tubulointerstitial nephritis with storiform fibrosis in a 76-year-old man. The patient exhibited lymphadenopathy, polyclonal hypergammaglobulinemia, and renal dysfunction and was diagnosed with AITL on the basis of lymph node biopsy findings. The serum IgG4 level was highly elevated.

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Idiopathic carpal tunnel syndrome is the most common entrapment neuropathy in hand surgery, and it is characterized by Noninflammatory fibrosis of subsynovial connective tissues. The prevalence and incidence differ between male and female individuals, and the mechanism underlying this difference remains largely unclear. In the present study, we collected subsynovial connective tissues from six male and six female patients diagnosed with idiopathic carpal tunnel syndrome during surgery.

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  • Secondary central nervous system (CNS) lymphomas often require specialized drugs, but current options have limited effectiveness; this case discusses CAR-T cell therapy as a potential solution.
  • A 66-year-old male with diffuse large B-cell lymphoma initially achieved remission but later showed signs of isolated CNS relapse, leading to treatment with high-dose methotrexate and ultimately CAR-T cell therapy.
  • The CAR-T therapy resulted in a second complete remission and demonstrated tolerable side effects, suggesting its potential as a safe and effective treatment for isolated secondary CNS lymphomas, highlighting the need for more research in this area.
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  • The study suggests a new grading criterion for follicular lymphoma that aligns more closely with pathologists' evaluations than the current World Health Organization (WHO) criteria.
  • Due to the difficulty in manually counting and identifying cell types like centroblasts and centrocytes, they utilize digital pathology and image processing for accurate cell classification.
  • A new dataset is created to assist in building a cell type classifier, which shows improved consistency with pathologist findings compared to the WHO standards.
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Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related neoplasm with male dominance and a poor prognosis. A better understanding of the genetic alterations and their functional roles in ENKTCL could help improve patient stratification and treatments. In this study, we performed a comprehensive genetic analysis of 178 ENKTCL cases to delineate the landscape of mutations, copy number alterations (CNA), and structural variations, identifying 34 driver genes including six previously unappreciated ones, namely, HLA-B, HLA-C, ROBO1, CD58, POT1, and MAP2K1.

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Aims: T-follicular helper (TFH) cells are effector T-cells that are crucial for B-cell selection and differentiation. T-cell lymphomas derived from TFH cells have distinct characteristics. Additionally, in the World Health Organization (WHO) classification 5th edition, three lymphomas were introduced as independent disease entities with TFH cell origin.

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Chronic lymphocytic leukemia (CLL) is rare in Japan. We conducted the nationwide, prospective observational study CLLRSG-01 to clarify the current state of CLL in Japan and to make accurate international comparisons by preparing naturally air-dried smears like those used in other countries. Of the 201 untreated patients enrolled and evaluated, 119 were diagnosed with CLL and 82 with non-CLL mature B-cell neoplasms, based on the WHO classification.

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  • EBV-positive nodal T- and natural killer-cell lymphoma (EBV+ nPTCL) is a type of cancer characterized by T-cell tumor cells that contain the Epstein-Barr virus, but its genetic basis has not been thoroughly studied.
  • Researchers conducted whole-exome and/or whole-genome sequencing on 22 cases of EBV+ nPTCL, identifying key mutations in TET2 (68%) and DNMT3A (32%), which are associated with poorer survival outcomes.
  • The study also highlighted frequent structural variations in the EBV genome, including deletions and integration of human genes like PD-L1, which is linked to increased expression of this protein and may play a role in the development of this lymphoma
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Unlabelled: Small cell lung cancer (SCLC) is exceptionally aggressive, with limited treatment options. Disialoganglioside (GD2) is highly expressed on SCLC and is considered a good target for chimeric antigen receptor (CAR) T cells (CART). Although GD2-directed CARTs (GD2-CART) exhibit cytotoxicity against various GD2-expressing tumors, they lack significant cytotoxicity against SCLC.

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In this study, we present a deep-learning-based multimodal classification method for lymphoma diagnosis in digital pathology, which utilizes a whole slide image (WSI) as the primary image data and flow cytometry (FCM) data as auxiliary information. In pathological diagnosis of malignant lymphoma, FCM serves as valuable auxiliary information during the diagnosis process, offering useful insights into predicting the major class (superclass) of subtypes. By incorporating both images and FCM data into the classification process, we can develop a method that mimics the diagnostic process of pathologists, enhancing the explainability.

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  • Secondary central nervous system involvement (sCNSi) in diffuse large B-cell lymphoma (DLBCL) is a serious condition, with a study showing that only 5.1% of lower-risk patients developed sCNSi over a median follow-up of 4.9 years.
  • The five-year cumulative incidence of sCNSi varied based on risk levels (4.0% for low risk to 11.5% for high risk), with lesions most commonly found in the stomach and paranasal cavity, the latter being a significant risk factor.
  • Despite a low incidence in lower-risk patients, the median overall survival after developing sC
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  • Regulatory B cells (Bregs) contribute to tumor growth in diffuse large B-cell lymphoma (DLBCL) by producing immune-suppressing cytokines like TGF-β and IL-10.
  • In a study of 123 DLBCL cases, 15 (12.2%) exhibited Breg characteristics, showing significantly worse survival outcomes compared to non-Breg cases.
  • Gene expression analysis revealed downregulation of key genes in Breg-type DLBCL, supporting the idea that Breg markers correlate with poor prognosis in DLBCL patients.
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  • Peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) can be divided into two main subtypes: PTCL-TBX21 and PTCL-GATA3, each exhibiting different characteristics.
  • In a study involving 100 Japanese patients, PTCL-TBX21 showed better treatment response and lower CD4 positivity compared to PTCL-GATA3, which also had worse overall survival rates.
  • The findings suggest that classifying PTCL-NOS based on these subtypes can help predict patient outcomes and tailor immune therapy.
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Introduction: Renal involvement by non-Hodgkin's lymphoma is very rare, and the kidney as the primary site of this lymphoma is much more uncommon. We report a case of primary renal peripheral T-cell lymphoma, not otherwise specified, treated with partial nephrectomy.

Case Presentation: A 63-year-old man was hospitalized with coronavirus infectious disease, emerged in 2019 in the emergency department.

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We report a case of a 24-year-old man who developed angioimmunoblastic T-cell lymphoma (AITL) after treatment for refractory lymphocyte-rich classic Hodgkin lymphoma (LR-CHL). This patient was treated with the BV+AVD (brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine) protocol for LR-CHL but progressed before completing chemotherapy. The pathological imaging showed the typical findings of LR-CHL at the first onset and first progression.

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  • * This study examined the effects of CD47 and SIRPα in 84 myeloid sarcoma biopsy samples, classifying patients based on whether SIRPα was present in tumor cells (nSIRPα) or surrounding stromal cells (miSIRPα).
  • * Patients with CD47-positive tumors experienced better overall survival rates and greater lymphocytic infiltration, marking a new finding that suggests CD47 may have a protective role in myeloid sarcoma, although further studies on genetic factors
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  • Pathologic evaluation is essential for diagnosing malignant lymphomas, but there are currently no standardized criteria for assessing their morphology.
  • Researchers analyzed the cell nuclei from 10 patients with different lymphoma types, measuring 17 parameters related to their characteristics and found statistically significant differences between them.
  • A new decision tree model demonstrated high sensitivity, specificity, and accuracy in identifying distinctive features of diffuse large B-cell lymphoma (DLBCL), suggesting that quantitative morphology can improve lymphoma diagnosis.
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Functionally rejuvenated human papilloma virus-specific cytotoxic T lymphocytes (HPV-rejTs) generated from induced pluripotent stem cells robustly suppress cervical cancer. However, autologous rejT generation is time consuming, leading to difficulty in treating patients with advanced cancer. Although use of allogeneic HPV-rejTs can obviate this, the major obstacle is rejection by the patient immune system.

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Most meningiomas, which are frequent central nervous system tumors, are classified as World Health Organization (WHO) grade 1 because of their slow-growing nature. However, the recurrence rate varies and is difficult to predict using conventional histopathological diagnoses. Leucine-rich α-2 glycoprotein 1 (LRG1) is involved in cell signal transduction, cell adhesion, and DNA repair and is a predictive biomarker in different malignant tumors; however, such a relationship has not been reported in meningiomas.

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