Waldenström macroglobulinemia (WM) is a B-cell lymphoproliferative disease characterized by IgM monoclonal gammopathy and bone marrow (BM) infiltration caused by lymphoplasmacytic lymphoma. The MYD88 L265P variant is present in > 90% of WM cases.We used droplet digital PCR (ddPCR) to detect MYD88 L265P in initial BM samples from 15 patients with WM and assessed the implication of variant burden as a tumor load and prognostic marker. MYD88 L265P burden correlated with clinical indicators, including peripheral blood and BM lymphocyte percentages (P < 0.001 and P = 0.003, respectively), serum lactate dehydrogenase level (P = 0.045), and platelet count (P = 0.003). Patients classified into intermediate and high groups according to the Revised International Prognostic Score System for WM had higher MYD88 L265P copies/μL than patients in very low and low groups (P = 0.017), as had patients with minor response or stable disease after primary treatment than those with complete, partial, or very good partial response (P = 0.034).MYD88 L265P burden correlates well with multiple clinical indicators and has prognostic relevance, making it a potential marker for assessing tumor burden and predicting prognosis in WM.

Measurable residual disease (MRD) testing, a standard procedure in B-lymphoblastic leukemia (B-ALL) diagnostics, is assessed using multiparametric flow cytometry (MFC) and next-generation sequencing (NGS) analysis of immunoglobulin gene rearrangements. We evaluated the concordance between eight-color, two-tube MFC-MRD the LymphoTrack NGS-MRD assays using 139 follow-up samples from 54 pediatric patients with B-ALL. We also assessed the effect of hemodilution in MFC-MRD assays. The MRD-concordance rate was 79.9% (N = 111), with 25 (18.0%) and 3 (2.2%) samples testing positive only by NGSMRD (MFC − NGS + MRD) and MFC-MRD (MFC + NGS − MRD), respectively. We found a significant correlation in MRD values from total nucleated cells between the two methods (r = 0.736 [0.647–0.806], P < 0.001). The median MRD value of MFC − NGS + MRD samples was estimated to be 0.0012% (0.0001%–0.0263%) using the NGS-MRD assays. Notably, 14.3% of MFC − NGS + MRD samples showed NGS-MRD values below the limit of detection in the MFC-MRD assays. The percentages of hematogones detected in MFC-MRD assays significantly differed between the discordant and concordant cases (P < 0.001). MFC and NGS-MRD assays showed relatively high concordance and correlation in MRD assessment, whereas the NGS-MRD assay detected MRD more frequently than the MFC-MRD assay in pediatric B-ALL. Evaluating the hematogone percentages can aid in assessing the impact of sample hemodilution.

Purpose: Vascular endothelial growth factor tyrosine kinase inhibitors (TKIs) have been the standard of care for advanced and metastatic clear cell renal cell carcinoma (ccRCC). However, the therapeutic effect of TKI monotherapy remains unsatisfactory given the high rates of acquired resistance to TKI therapy despite favorable initial tumor response. Materials and Methods: To define the TKI-resistance mechanism and identify new therapeutic target for TKI-resistant ccRCC, an integrative differential gene expression analysis was performed using acquired resistant cohort and a public dataset. Sunitinib-resistant RCC cell lines were established and used to test their malignant behaviors of TKI resistance through in vitro and in vivo studies. Immunohistochemistry was conducted to compare expression between the tumor and normal kidney and verify expression of pathway-related proteins. Results: Integrated differential gene expression analysis revealed increased interferon-induced transmembrane protein 3 (IFITM3) expression in post-TKI samples. IFITM3 expression was increased in ccRCC compared with the normal kidney. TKI-resistant RCC cells showed high expression of IFITM3 compared with TKI-sensitive cells and displayed aggressive biologic features such as higher proliferative ability, clonogenic survival, migration, and invasion while being treated with sunitinib. These aggressive features were suppressed by the inhibition of IFITM3 expression and promoted by IFITM3 overexpression, and these findings were confirmed in a xenograft model. IFITM3-mediated TKI resistance was associated with the activation of TRAF6 and MAPK/AP-1 pathways. Conclusions These results demonstrate IFITM3-mediated activation of the TRAF6/MAPK/AP-1 pathways as a mechanism of acquired TKI resistance, and suggest IFITM3 as a new target for TKI-resistant ccRCC.

Hereditary hemolytic anemia (HHA) is considered a group of rare hematological diseases in Korea, primarily because of its unique ethnic characteristics and diagnostic challenges.Recently, the prevalence of HHA has increased in Korea, reflecting the increasing number of international marriages and increased awareness of the disease. In particular, the diagnosis of red blood cell (RBC) enzymopathy experienced a resurgence, given the advances in diagnostic techniques. In 2007, the RBC Disorder Working Party of the Korean Society of Hematology developed the Korean Standard Operating Procedure for the Diagnosis of Hereditary Hemolytic Anemia, which has been continuously updated since then. The latest Korean clinical practice guidelines for diagnosing HHA recommends performing nextgeneration sequencing as a preliminary step before analyzing RBC membrane proteins and enzymes. Recent breakthroughs in molecular genetic testing methods, particularly nextgeneration sequencing, are proving critical in identifying and providing insight into cases of HHA with previously unknown diagnoses. These innovative molecular genetic testing methods have now become important tools for the management and care planning of patients with HHA. This review aims to provide a comprehensive overview of recent advances in molecular genetic testing for the diagnosis of HHA, with particular emphasis on the Korean context.

Background: The efficacy and safety of direct oral anticoagulants (DOACs) versus warfarin in patients with antiphospholipid syndrome-associated venous thromboembolism (APS-VTE) remain uncertain. We aimed to evaluate efficacy and safety of DOACs in patients with APSVTE. Methods: Using the Korean Health Insurance Review and Assessment Service database, we retrospectively identified all APS-VTE cases. We examined the VTE recurrence, arterial thrombosis, death and bleeding in patients who received DOACs compared with warfarin for therapeutic anticoagulation. Results: Of all the VTE cases (n = 84,916) detected between 2014 and 2018, patients with APS-VTE (n = 410) accounted for 0.48%. Most patients with APS-VTE (73%) were aged < 60 years. The recurrent VTE occurred in 8 of 209 patients (3.8%) who received DOACs and in 7 of 201 (3.5%) who received warfarin (relative risk [RR], 1.099; 95% confidence interval [CI], 0.41–2.98; P = 1.000). The arterial thrombosis (ATE) occurred in 8 of 209 patients (3.8%) who received DOAC and in 20 of 201 (10%) who received warfarin (RR, 0.385; 95% CI, 0.17–0.85; P = 0.024). The composite outcomes of VTE recurrence, ATE, or mortality were significantly lower in patients (9.1%) on DOAC than in those (16.3%) on warfarin (RR, 0.537; 95% CI, 0.32–0.91; P = 0.028). The bleeding outcome occurred in 7 of 209 (3.4%) patients in the DOACs group and 7 of 201 (3.5%) patients in the warfarin group (RR, 0.96; 95% CI, 0.34–2.69; P = 0.840). Conclusion In patients with APS-VTE, DOACs group showed comparable rates of recurrent VTE, bleeding, and deaths, but a significantly lower incidence of ATE and composite outcomes compared with the warfarin group in Korea.

Aplastic anemia, mental retardation, and dwarfism (AMeD) syndrome, also known as aldehyde degradation deficiency (ADD) syndrome, is an autosomal recessive disorder caused by mutations in the ALDH2 and ADH5 genes, leading to decreased activity of the aldehyde dehydrogenase 2 (ALDH2) and alcohol dehydrogenase 5 (ADH5) enzymes, subsequently triggering enhanced cellular levels of formaldehyde and diverse multisystem manifestations. Herein, we present the case of a 7-year-old girl with AMeD syndrome, characterized by pancytopenia, developmental delay, microcephaly, epilepsy, and myelodysplastic syndrome. Whole-exome sequencing revealed compound heterozygous variants (c.832G＞C and c.678delA) in the ADH5 gene and a heterozygous pathogenic variant (c.1510G＞A) in the ALDH2 gene. This case underscores the complexity of AMeD syndrome, emphasizing the importance of genetic testing to ensure diagnosis and aid in the development of potential targeted therapeutic approaches.

Aplastic anemia, mental retardation, and dwarfism (AMeD) syndrome, also known as aldehyde degradation deficiency (ADD) syndrome, is an autosomal recessive disorder caused by mutations in the ALDH2 and ADH5 genes, leading to decreased activity of the aldehyde dehydrogenase 2 (ALDH2) and alcohol dehydrogenase 5 (ADH5) enzymes, subsequently triggering enhanced cellular levels of formaldehyde and diverse multisystem manifestations. Herein, we present the case of a 7-year-old girl with AMeD syndrome, characterized by pancytopenia, developmental delay, microcephaly, epilepsy, and myelodysplastic syndrome. Whole-exome sequencing revealed compound heterozygous variants (c.832G＞C and c.678delA) in the ADH5 gene and a heterozygous pathogenic variant (c.1510G＞A) in the ALDH2 gene. This case underscores the complexity of AMeD syndrome, emphasizing the importance of genetic testing to ensure diagnosis and aid in the development of potential targeted therapeutic approaches.

Germline predisposition (GPD) to hematological malignancies has gained interest because of the increased use of genetic testing in this field. Recent studies have suggested that GPD is underrecognized and requires appropriate genomic testing for an accurate diagnosis. Identification of GPD significantly affects patient management and has diverse implications for family members. This review discusses the reasons for testing GPD in hematologic malignancies and explores the considerations necessary for appropriate genomic testing. The aim is to provide insights into how these genetic insights can inform treatment strategies and genetic counseling, ultimately enhancing patient care.

Germline predisposition (GPD) to hematological malignancies has gained interest because of the increased use of genetic testing in this field. Recent studies have suggested that GPD is underrecognized and requires appropriate genomic testing for an accurate diagnosis. Identification of GPD significantly affects patient management and has diverse implications for family members. This review discusses the reasons for testing GPD in hematologic malignancies and explores the considerations necessary for appropriate genomic testing. The aim is to provide insights into how these genetic insights can inform treatment strategies and genetic counseling, ultimately enhancing patient care.

Aplastic anemia, mental retardation, and dwarfism (AMeD) syndrome, also known as aldehyde degradation deficiency (ADD) syndrome, is an autosomal recessive disorder caused by mutations in the ALDH2 and ADH5 genes, leading to decreased activity of the aldehyde dehydrogenase 2 (ALDH2) and alcohol dehydrogenase 5 (ADH5) enzymes, subsequently triggering enhanced cellular levels of formaldehyde and diverse multisystem manifestations. Herein, we present the case of a 7-year-old girl with AMeD syndrome, characterized by pancytopenia, developmental delay, microcephaly, epilepsy, and myelodysplastic syndrome. Whole-exome sequencing revealed compound heterozygous variants (c.832G＞C and c.678delA) in the ADH5 gene and a heterozygous pathogenic variant (c.1510G＞A) in the ALDH2 gene. This case underscores the complexity of AMeD syndrome, emphasizing the importance of genetic testing to ensure diagnosis and aid in the development of potential targeted therapeutic approaches.