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Background: DNA methylation is a form of epigenetic modification that regulates gene expression. However, there are limited data on the comprehensive analysis of DNA methylation regulated gene mutations (DMRGM) in acute myeloid leukemia (AML) mainly referring to DNA methyltransferase 3α (DNMT3A), isocitrate dehydrogenase 1 (IDH1), isocitrate dehydrogenase 2 (IDH2), and Tet methylcytidine dioxygenase 2 (TET2). Results: A retrospective study of the clinical characteristics and gene mutations in 843 newly diagnosed non-M3 AML patients was conducted between January 2016 and August 2019. 29.7% (250/843) of patients presented with DMRGM. It was characterized by older age, higher white blood cell count, and higher platelet count (P < 0.05). DMRGM frequently coexisted with FLT3-ITD, NPM1, FLT3-TKD, and RUNX1 mutations (P < 0.05). The CR/CRi rate was only 60.3% in DMRGM patients, significantly lower than in non-DMRGM patients (71.0%, P = 0.014). In addition to being associated with poor overall survival (OS), DMRGM was also an independent risk factor for relapse-free survival (RFS) (HR: 1.467, 95% CI: 1.030–2.090, P = 0.034). Furthermore, OS worsened with an increasing burden of DMRGM. Patients with DMRGM may be benefit from hypomethylating drugs, and the unfavorable prognosis of DMRGM can be overcome by hematopoietic stem cell transplantation (HSCT). For external validation, the BeatAML database was downloaded, and a significant association between DMRGM and OS was confirmed (P < 0.05). Conclusion: Our study provides an overview of DMRGM in AML patients, which was identified as a risk factor for poor prognosis. [ABSTRACT FROM AUTHOR]

Background: DNA methylation is a form of epigenetic modification that regulates gene expression. However, there are limited data on the comprehensive analysis of DNA methylation regulated gene mutations (DMRGM) in acute myeloid leukemia (AML) mainly referring to DNA methyltransferase 3α (DNMT3A), isocitrate dehydrogenase 1 (IDH1), isocitrate dehydrogenase 2 (IDH2), and Tet methylcytidine dioxygenase 2 (TET2). Results: A retrospective study of the clinical characteristics and gene mutations in 843 newly diagnosed non-M3 AML patients was conducted between January 2016 and August 2019. 29.7% (250/843) of patients presented with DMRGM. It was characterized by older age, higher white blood cell count, and higher platelet count (P < 0.05). DMRGM frequently coexisted with FLT3-ITD, NPM1, FLT3-TKD, and RUNX1 mutations (P < 0.05). The CR/CRi rate was only 60.3% in DMRGM patients, significantly lower than in non-DMRGM patients (71.0%, P = 0.014). In addition to being associated with poor overall survival (OS), DMRGM was also an independent risk factor for relapse-free survival (RFS) (HR: 1.467, 95% CI: 1.030–2.090, P = 0.034). Furthermore, OS worsened with an increasing burden of DMRGM. Patients with DMRGM may be benefit from hypomethylating drugs, and the unfavorable prognosis of DMRGM can be overcome by hematopoietic stem cell transplantation (HSCT). For external validation, the BeatAML database was downloaded, and a significant association between DMRGM and OS was confirmed (P < 0.05). Conclusion: Our study provides an overview of DMRGM in AML patients, which was identified as a risk factor for poor prognosis. [ABSTRACT FROM AUTHOR]

Background: Type 3 von Willebrand disease (VWD) exhibits severe hemorrhagic tendency with complicated pathogenesis. The C-terminal cystine knot (CTCK) domain plays an important role in the dimerization and secretion of von Willebrand factor (VWF). The CTCK domain has four intrachain disulfide bonds including Cys2724-Cys2774, Cys2739-Cys2788, Cys2750-Cys2804 and Cys2754-Cys2806, and the single cysteine mutation in Cys2739-Cys2788, Cys2750-Cys2804 and Cys2754-Cys2806 result in type 3 VWD, demonstrating the crucial role of these three disulfide bonds in VWF biosynthesis, however, the role of the remaining disulfide bond Cys2724-Cys2774 remains unclear. Method and results: In this study, by the next-generation sequencing we found a missense mutation a c.8171G>A (C2724Y) in the CTCK domain of VWF allele in a patient family with type 3 VWD. In vitro, VWF C2724Y protein was expressed normally in HEK-293T cells but did not form a dimer or secrete into cell culture medium, suggesting that C2724 is critical for the VWF dimerization, and thus for VWF multimerization and secretion. Conclusions: Our findings provide the first genetic evidence for the important role of Cys2724-Cys2774 in VWF biosynthesis and secretion. Therefore, all of the four intrachain disulfide bonds in CTCK monomer contribute to VWF dimerization and secretion. [ABSTRACT FROM AUTHOR]

Background: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by hamartomas in any organ systems. Mutations in the TSC1 or TSC2 gene lead to the dysfunction of hamartin or tuberin proteins, which cause tuberous sclerosis complex. Case presentation: We describe the clinical characteristics of patients from a Chinese family with tuberous sclerosis complex and analyze the functional consequences of their causal genetic mutations. A novel heterozygous mutation (c.3610G > A) at the last nucleotide of exon 29 in TSC2 was identified. On the protein level, this variant was presumed to be a missense mutation (p.Gly1204Arg). However, the splicing assay revealed that this mutation also leads to the whole TSC2 exon 29 skipping, besides the wild-type transcript. The mutated transcript results in an in-frame deletion of 71 amino acids (p.Gly1133_Thr1203del) and its ratio with the normal splice product is of about 44:56. Conclusions: The novel c.3610G > A TSC2 mutation was identified in association with tuberous sclerosis complex. And it was proven to code both for a missense-carrying transcript (56%), and for an isoform lacking exon 29 (44%). [ABSTRACT FROM AUTHOR]