Flow cytometric analysis of CD34 CD38 cells; cell frequency and immunophenotype based on CD45RA expression pattern.

Introduction: The CD34 CD38 population in bone marrow includes hematopoietic stem/progenitor cells. Recently, in acute myeloid leukemia, the focus has shifted to flow cytometry analysis targeting CD34 CD38 leukemic cells due to their effectiveness in minimal/measurable residual disease detection and prognosis prediction. Nevertheless, the immunophenotype and cell frequency of these cells in the bone marrow, in the absence of leukemic cells, remains unknown.

Low-Level Germline 48,XYY,+21 Mosaicism Associated with Transient Abnormal Myelopoiesis in a Phenotypically Normal Neonate.

Transient abnormal myelopoiesis (TAM) is a unique neonatal leukemoid reaction caused by a pathognomonic GATA1 mutation in conjunction with the gene dosage effect of trisomy 21, which is either of germline or somatic origin. We encountered a 48,XYY,+21 phenotypically normal neonate with Down syndrome who developed TAM due to cryptic germline mosaicism. Quantification of the mosaic ratio was complicated by an overestimation bias of hyperproliferating TAM within the germline component.

Sensitive detection of GATA1 mutations using complementary DNA-based analysis for transient abnormal myelopoiesis associated with the Down syndrome.

Introduction: GATA1 mutation plays an important role in initiating transient abnormal myelopoiesis (TAM) and in the clonal evolution towards acute megakaryoblastic leukaemia (AMKL) associated with Down syndrome (DS). This study aimed to develop and validate the clinical utility of a complementary DNA (cDNA) analysis in parallel with the conventional genomic DNA (gDNA) Sanger sequencing (Ss), as an initial screening test for GATA1 mutations.

Methods: GATA1 mutations were evaluated using both gDNA and cDNA in 14 DS patients using Ss and fragment analysis (FA), respectively.

VS38 staining contributes to a novel gating strategy in flow cytometry for small B cell lymphoma, especially in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia.

Background: Multi-parametric flow cytometry (MFC) is a helpful tool for detecting neoplastic cells in malignant lymphoma; however, lymphoma cells can be difficult to detect when characteristic immunophenotypic abnormalities are not evident. We evaluated the stainability of VS38, which is used for multiple myeloma, in normal and abnormal B cells using MFC to develop a new strategy for detecting lymphoma cells.

Methods: We compared the median fluorescence intensity of VS38 staining in lymphocytes from patients without hematopoietic neoplasms and in B cells from 26 patients with B cell lymphoma (BCL).

cDNA-Based Mutation Screening Using a Combination of High-Resolution Melting Curve and Fragment Analysis Facilitates Efficient CCR4 Mutation Analysis in Adult T-Cell Leukemia/Lymphoma.

Objectives: C-C chemokine receptor type 4 (CCR4) proteins are expressed on the neoplastic cells of adult T-cell leukemia/lymphoma (ATLL). As the mutation status of CCR4 gene is reported to correlate with significant clinical information such as prognosis and response to mogamulizumab, we aimed to establish a screening method that is suitable for clinical laboratory tests.

Methods: In 34 patients with ATLL, CCR4 mutation analysis, high-resolution melting (HRM) analysis, fragment analysis, and direct sequencing were performed using both genomic DNA and complementary DNA (cDNA).

Cell-free DNA Oncogene Copy Number as a Surrogate Molecular Biomarker in ALK/MYCN-coamplified Neuroblastoma.

Secondary expansion and/or evolution of aggressive subclones are associated with the disease progression and resistance to chemotherapy in neuroblastoma, and it is important to track the clonal changes during the treatment period. Cell-free (cf) DNA analysis, namely liquid biopsy, can detect the genomic change of tumor cells without surgical procedures. In this report, we showed that serial polymerase chain reaction-based cf DNA neuroblastoma proto-oncogene quantification is sensitive enough to evaluate the aggressive cellular characteristics of ALK/MYCN-coamplified neuroblastoma and stressed the promise of cf DNA analyses as a reliable molecular marker in advanced neuroblastoma.

VS38 as a promising CD38 substitute antibody for flow cytometric detection of plasma cells in the daratumumab era.

The development of effective therapies has enabled long-term survival for many patients with multiple myeloma (MM). However, the administration of antibody drugs, such as daratumumab, which bind to plasma cell (PC) surface proteins, may prevent PC detection by flow cytometry. We propose VS38 as an alternative antibody for CD38.

Investigation of screening method for DNMT3A mutations by high-resolution melting analysis in acute myeloid leukemia.

Introduction: Acute myeloid leukemia (AML) is a heterogeneous disease associated with various genetic abnormalities. Somatic mutations in nucleophosmin 1 (NPM1), fms-related tyrosine kinase 3 (FLT3), and DNA methyltransferase 3 alpha (DNMT3A) are the most frequent mutations associated with AML. However, because DNMT3A mutations are broadly distributed, they are challenging to analyze in routine laboratory tests.

Evaluation of SF3B1 Mutation Screening by High-Resolution Melting Analysis and its Clinical Utility for Myelodysplastic Syndrome with Ring Sideroblasts at the Point of Diagnosis.

Background: SF3B1 (splicing factor 3B subunit-1) somatic mutation is specifically detected in myelodysplastic syndrome (MDS) with ring sideroblasts (MDS-RS). We investigated the sensitivity and utility of SF3B1 mutation analysis as a clinical laboratory test.

Method: Detection limit for SF3B1 mutations by high-resolution melting (HRM) analysis was investigated by plasmid mixture.

CCAR1/CoCoA pair-mediated recruitment of the Mediator defines a novel pathway for GATA1 function.

The MED1 subunit of the Mediator transcriptional coregulator complex coactivates GATA1 and induces erythropoiesis. Here, we show the dual mechanism of GATA1- and MED1-mediated transcription. MED1 expression levels in K562 erythroleukemia cells paralleled the levels of GATA1-targeted gene transcription and erythroid differentiation.

Mediator subunit MED1 is a T3-dependent and T3-independent coactivator on the thyrotropin β gene promoter.

The MED1 subunit of the Mediator transcriptional coregulator complex is a nuclear receptor-specific coactivator. A negative feedback mechanism of thyroid-stimulating hormone (TSH, or thyrotropin) expression in the thyrotroph in the presence of triiodothyronine (T3) is employed by liganded thyroid hormone receptor β (TRβ) on the TSHβ gene promoter, where conventional histone-modifying coactivators act as corepressors. We now provide evidence that MED1 is a ligand-dependent positive cofactor on this promoter.

Mediator subunits MED1 and MED24 cooperatively contribute to pubertal mammary gland development and growth of breast carcinoma cells.

The Mediator subunit MED1 is essential for mammary gland development and lactation, whose contribution through direct interaction with estrogen receptors (ERs) is restricted to involvement in pubertal mammary gland development and luminal cell differentiation. Here, we provide evidence that the MED24-containing submodule of Mediator functionally communicates specifically with MED1 in pubertal mammary gland development. Mammary glands from MED1/MED24 double heterozygous knockout mice showed profound retardation in ductal branching during puberty, while single haploinsufficient glands developed normally.