한국 von Willebrand병 환자의 von Willebrand 인자 유전자 돌연변이 조사

BACKGROUND: We intended to find the mutations of von Willebrand factor (VWF) gene as the most important contributing factor of von Willebrand disease (VWD) in Korean patients. METHODS: In 40 known vWD patients mutations of vWF gene were sought by direct sequencing of PCR products targeting exons 18, 19, 20, 26, 28 and 52 frequently implicated as the locations of mutation. For factors other than VWF gene contributing to VWD phenotype, we tested ABO blood group and measured ADAMTS13 activity in VWD patients. RESULTS: Twenty-seven cases (67.5%) were type 1 vWD, 3 cases (7.5%) type 3, and 5 cases (12.5%) type 2A. Three cases were type 2A or 2B (7.5%) and 2 cases were suspected to be type 2N (5.0%). Among them six candidate missense mutations were found: V1279I, R1306W, R1308C, and V1316M were previously reported in type 2B and type 1 vWD, and C858W and T1477I were novel findings. All patients were heterozygotes. Blood group O was overly represented in VWD patients, while ADAMTS13 activity of the patients was not significantly different from that of normal control. CONCLUSIONS: Mutation of VWF gene detected by genetic studies can significantly improve the diagnostic accuracy, especially in subtype assignment of VWD. Two novel mutations, C858W and T1477I associated with VWD were found and expected to contribute to the elucidation of its pathophysiology.ope

Genetic heterogeneity and prognostic impact of recurrent ANK2 and TP53 mutations in mantle cell lymphoma: a multi-centre cohort study

The molecular features of mantle cell lymphoma (MCL), including its increased incidence, and complex therapies have not been investigated in detail, particularly in East Asian populations. In this study, we performed targeted panel sequencing (TPS) and whole-exome sequencing (WES) to investigate the genetic alterations in Korean MCL patients. We obtained a total of 53 samples from MCL patients from five Korean university hospitals between 2009 and 2016. We identified the recurrently mutated genes such as SYNE1, ATM, KMT2D, CARD11, ANK2, KMT2C, and TP53, which included some known drivers of MCL. The mutational profiles of our cohort indicated genetic heterogeneity. The significantly enriched pathways were mainly involved in gene expression, cell cycle, and programmed cell death. Multivariate analysis revealed that ANK2 mutations impacted the unfavourable overall survival (hazard ratio [HR] 3.126; P = 0.032). Furthermore, TP53 mutations were related to worse progression-free survival (HR 7.813; P = 0.043). Among the recurrently mutated genes with more than 15.0% frequency, discrepancies were found in only 5 genes from 4 patients, suggesting comparability of the TPS to WES in practical laboratory settings. We provide the unbiased genetic landscape that might contribute to MCL pathogenesis and recurrent genes conferring unfavourable outcomes.ope

Recurrent somatic mutations and low germline predisposition mutations in Korean ALL patients

In addition to somatic mutations, germline genetic predisposition to hematologic malignancies is currently emerging as an area attracting high research interest. In this study, we investigated genetic alterations in Korean acute lymphoblastic leukemia/lymphoma (ALL) patients using targeted gene panel sequencing. To this end, a gene panel consisting of 81 genes that are known to be associated with 23 predisposition syndromes was investigated. In addition to sequence variants, gene-level copy number variations (CNVs) were investigated as well. We identified 197 somatic sequence variants and 223 somatic CNVs. The IKZF1 alteration was found to have an adverse effect on overall survival (OS) and relapse-free survival (RFS) in childhood ALL. We found recurrent somatic alterations in Korean ALL patients similar to previous studies on both prevalence and prognostic impact. Six patients were found to be carriers of variants in six genes associated with primary immunodeficiency disorder (PID). Of the 81 genes associated with 23 predisposition syndromes, this study found only one predisposition germline mutation (TP53) (1.1%). Altogether, our study demonstrated a low probability of germline mutation predisposition to ALL in Korean ALL patients.ope

Relationship between Myelodysplastic Syndrome and Epstein-Barr Virus or Human Parvovirus Bl9 Infection

Background :The mechanisms responsible for the disturbed hematopoiesis in myelodysplastic syndrome (MDS) include the expansion of abnormal clones, defects in cellular differentiation and he perturbation in the production of hematopoietic regulatory factors. Recently, viral infection such as immunodeficiency virus is known to induce myelodysplasia. And viral infection evokes the production of several cytokines. Therefore, abnormal production of cyrokine may be a potential candidate for the pathogenesis of MDS after viral infections such as Epstein-Barr virus (EBV) and human parvovirus B19. Method :We investigated bone marrow aspiration slides from 17 patients with MDS referred for the bone marrow study, over a period from January, 1992 to April, 1996. To clarify the contribution of EBV and human parvovirus B19 infections to the pathogenesis of MDS, DNA-PCR for EBV and human parvovirus Bl9 was used. Result :The EBV and human parvovirus B19-PCR results were all negative in 17 patients with MDS. Conclusion :EBV and human parvovirus Bl9 infections may not be associated with the major pathogenesis of MDSope

Homozygous V/V (677C to T) and D/D (2756G to A) variants in the methylenetetrahydrofolate and methionine synthase genes in a case of hyperhomocysteinemia with stroke at young age

Hyperhomocysteinemia is known to be associated with an increased risk of myocardial infarction, stroke, peripheral arterial disease, and venous thrombosis. Gene polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) may account for reduced enzyme activity and hyperhomocysteinemia. A recent study has documented evidence of polygenic regulation of plasma homocyteine. We report here on a case of occlusive stroke at young age and hyperhomocysteinemia with homozygous V/V (677C to T) variant in the MTHFR gene as well as homozygous D/D (2756G to A) variant in the MS gene.ope

A Case of Therapy-Related Acute Leukemia With Mixed Phenotype With BCR-ABL1 After Treatment of Diffuse Large B-Cell Lymphoma

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Expanding the Non-Invasive Diagnosis of Acute Rejection in Kidney Transplants Through Detection of Donor-Derived DNA in Urine: Proof-of-Concept Study

Background: Approximately 10%-20% of kidney transplant (KT) recipients suffer from acute rejection (AR); thus, sensitive and accurate monitoring of allograft status is recommended. We evaluated the clinical utility of donor-derived DNA (dd-DNA) detection in the urine of KT recipients as a non-invasive means for diagnosing AR. Methods: Urine samples serially collected from 39 KT recipients were tested for 39 single-nucleotide variant loci selected according to technical criteria (i.e., high minor allele frequency and low analytical error) using next-generation sequencing. The fraction of dd-DNA was calculated and normalized by the urine creatinine (UCr) level (%dd-DNA/UCr). The diagnostic performance of %dd-DNA/UCr for AR was assessed by ROC curve analysis. Results: There was an increasing trend of %dd-DNA/UCr in the AR group before subsequent graft injury, which occurred before (median of 52 days) histological rejection. The serum creatinine (SCr) level differed significantly between the AR and non-AR groups at two and four months of follow-up, whereas %dd-DNA/UCr differed between the groups at six months of follow-up. The combination of %dd-DNA/UCr, SCr, and spot urine protein (UPtn)/UCr showed high discriminating power, with an area under the ROC curve of 0.93 (95% confidence interval: 0.81-1.00) and a high negative predictive value of 100.0%. Conclusions: Although the dd-DNA-based test cannot eliminate the need for biopsy, the high negative predictive value of this marker could increase the prebiopsy probability of detecting treatable injury to make biopsy an even more effective diagnostic tool.ope

Constitutional pericentric inversion 9 in Korean patients with chronic myelogenous leukemia

BACKGROUND: Although the pericentric inversion of chromosome 9, inv(9)(p11q13), is generally considered a normal variation, it is also associated with solid tumors and several hematologic malignancies such as biphenotypic acute leukemia, ALL, AML, and myeloproliferative neoplasms. However, to the best of our knowledge, there have been no reports that suggest an association between CML and constitutional pericentric inversion of chromosome 9. The purpose of this retrospective study was to investigate the frequency and clinical features of CML patients with concomitant inv(9) and t(9;22)(q34;q11.2) variation at our institution. METHODS: We reviewed the bone marrow chromosome database entries between October 2006 and December 2008 to identify patients with concomitant inv(9) and t(9;22) variations. Laboratory and clinical data of the patients were obtained from the electronic medical record system. RESULTS: Among the 51 CML patients, 4 (7.8%) had concomitant inv(9) and t(9;22) variations. CONCLUSIONS: Although the association between inv(9) variation and CML is still controversial, we believe that hematologists should consider the role of constitutional inv(9) variation in CML patients to avoid overlooking the impaired engraftment potential of hematopoietic stem cells harboring inv(9). Therefore, we suggest that more effort should be invested to develop cytogenetic tests for detecting constitutional inv(9) variation in CML patientsope

A case of pseudoisodicentric chromosome 18q detected at prenatal diagnosis

Although trisomy 18 (Edwards' syndrome) or the terminal deletion syndromes of 18p and 18q have been occasionally detected, pseudoisodicentric chromosome 18 is a very rare constitutional chromosomal abnormality. We describe a case of pseudoisodicentric chromosome 18q without mosaicism, which was confirmed from fetal cells in the amniotic fluid used for prenatal diagnosis of multiple congenital anomalies. A 23-yr-old pregnant woman was suspected of having a fetal anomaly at 18(+3) weeks gestation. In sonography, the fetus showed multiple anomalies: bilateral overt ventriculomegaly in the brain, ventricular septal defect and valve anomaly in the heart, bilateral club foot, polydactyly, meningocele, and a single umbilical artery. The pregnancy was terminated and a conventional G-banded chromosome study was performed using amniotic fluid. Twenty metaphase cells among the cultured amniocytes showed a 46,XX,psu idic(18)(q22). Consequently, the fetus had partial trisomy (18pter-->q22) and partial monosomy (18q22-->qter). Both parents were confirmed to have a normal karyotypeope

Minor BCR-ABL1-Positive Acute Myeloid Leukemia Associated With the NPM1 Mutation and FLT3 Internal Tandem Duplication

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