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Background: Imatinib (IM) is the primary treatment for patients with chronic-phase CML (CML-CP). However, an increasing number of CML-CP patients have developed resistance to IM. Our study aims to explore the expression of miR-629-5p in extracellular vesicles (EVs) from both IM-sensitive (K562) and resistant (K562-Re) CML cell lines and to investigate the impact of regulating miR-629-5p expression on the biological characteristics of K562 and K562-Re cells., Methods: Assess miR-629-5p expression levels in IM-sensitive and resistant CML cell lines. Separate EVs and verify it. EVs from K562-Re cells were co-cultured with K562 cells to detect the expression level of miR-629-5p. Target genes of miR-629-5p were determined and validated through luciferase experiments. Examined by manipulating miR-629-5p expression in cells using transfection techniques. The expression level of phosphorylated proteins in the PI3K/AKT/mTOR signaling pathway after IM was detected in CML cell lines. In K562-Re cells, the expression level of phosphorylated protein in the PI3K/AKT/mTOR signaling pathway was detected after single transfection of miR-629-5p inhibitor and cotransfection of miR-629-5p inhibitor and siSENP2., Results: Increasing concentrations of EVs from K562-Re cells elevated miR-629-5p expression levels. The expression levels of miR-629-5p in CML cells varied with IM concentration and influenced the biological characteristics of cells. SENP2 was identified as a target gene of miR-629-5p. Furthermore, miR-629-5p was found to modulate the SENP2/PI3K/AKT/mTOR pathway, impacting IM resistance in CML cells., Conclusion: EVs from IM-resistant CML cells alter the expression of miR-629-5p in sensitive cells, activating the SENP2/PI3K/AKT/mTOR pathway and leading to IM resistance.

Leukemia is a malignant tumor with high heterogeneity and a complex evolutionary process. It is difficult to resolve the heterogeneity and clonal evolution of leukemia cells by applying traditional bulk sequencing techniques, thus preventing a deep understanding of the mechanisms of leukemia development and the identification of potential therapeutic targets. However, with the development and application of single-cell sequencing technology, it is now possible to investigate the gene expression profile, mutations, and epigenetic features of leukemia at the single-cell level, thus providing a new perspective for leukemia research. In this article, we review the recent applications and advances of single-cell sequencing technology in leukemia research, discuss its potential for enhancing our understanding of the mechanisms of leukemia development, discovering therapeutic targets and personalized treatment, and provide reference guidelines for the significance of this technology in clinical research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xie, An, Yang, Wang, Guo, Luo, Huang and Sun.)

Erythropoiesis is a highly complex and sophisticated multistage process regulated by many transcription factors, as well as noncoding RNAs. Anthrax toxin receptor 1 (ANTXR1) is a type I transmembrane protein that binds the anthrax toxin ligands and mediates the entry of its toxic part into cells. It also functions as a receptor for the Protective antigen (PA) of anthrax toxin, and mediates the entry of Edema factor (EF) and Lethal factor (LF) into the cytoplasm of target cells and exerts their toxicity. Previous research has shown that ANTXR1 inhibits the expression of γ -globin during the differentiation of erythroid cells. However, the effect on erythropoiesis from a cellular perspective has not been fully determined. This study examined the role of ANTXR1 on erythropoiesis using K562 and HUDEP-2 cell lines as well as cord blood CD34 + cells. Our study has shown that overexpression of ANTXR1 can positively regulate erythrocyte proliferation, as well as inhibit GATA1 and ALAS2 expression, differentiation, and apoptosis in K562 cells and hematopoietic stem cells. ANTXR1 knockdown inhibited proliferation, promoted GATA1 and ALAS2 expression, accelerated erythrocyte differentiation and apoptosis, and promoted erythrocyte maturation. Our study also showed that ANTXR1 may regulate the proliferation and differentiation of hematopoietic cells, though the Wnt/ β -catenin pathway, which may help to establish a possible therapeutic target for the treatment of blood disorders., Competing Interests: The authors declare no competing financial interests., (Copyright © 2022 Tingting Jin et al.)

Reactivation of fetal hemoglobin (HbF, α 2 γ 2) alleviates clinical symptoms in patients with β -thalassemia and sickle cell disease, although the regulatory mechanisms of γ -globin expression have not yet been fully elucidated. Recent studies found that interfering with the expression of the membrane protein ANTXR1 gene upregulated γ -globin levels. However, the exact mechanism by which ANTXR1 regulates γ -globin levels remains unclear. Our study showed that overexpression and knockdown of ANTXR1 in K562, cord blood CD34 + , and HUDEP-2 cells decreased and increased γ -globin expression, respectively. ANTXR1 regulates the reactivation of fetal hemoglobin (HbF, α 2 γ 2) in K562, cord blood CD34 + , and adult peripheral blood CD34 + cells through interaction with LRP6 to promote the nuclear entry of β -catenin and activate the Wnt/ β -catenin signaling pathway. The overexpression or knockdown of ANTXR1 on γ -globin and Wnt/ β -catenin signaling in K562 cells was reversed by the inhibitor XAV939 and the activator LiCl, respectively, where XAV939 inhibits the transcription of β -catenin in the Wnt pathway, but LiCl inhibits GSK3- β . We also showed that the binding ability of the rank4 site in the transcriptional regulatory region of the SOX6 gene to c-Jun was significantly increased after overexpression of ANTXR1 in K562 cells. SOX6 protein expression was increased significantly after overexpression of the c-Jun gene, indicating that the transcription factor c-Jun initiated the transcription of SOX6, thereby silencing γ -globin. Our findings may provide a new intervention target for the treatment of β -hemoglobinopathies., Competing Interests: The authors declare no competing financial interests., (Copyright © 2022 Tingting Jin et al.)

Objective: To detect mutation of LBR gene in a pedigree affected with Pelger-Huёt anomaly (PHA) and to explore its clinical characteristics., Methods: Genomic DNA was extracted from the pedigree and healthy controls. The 14 exons of the LBR gene were subjected to PCR amplification and Sanger sequencing. Suspected mutations were verified in other family members and 100 healthy controls. Polyphen-2 and SIFT software were used to predict the effect of the mutation, and Swiss-model software was used to simulate the protein structure., Results: Three patients were found to carry a c.893G>A mutation in exon 8 of the LBR gene, which resulted in substitution of the 298th amino acid residue glycine by glutamic acid (p.Gly298Glu). The same mutation was not found in healthy family members and 100 healthy controls. The mutation was predicted to be damaging. Bioinformatic simulation showed the mutation has altered the 3D structure of the LBR protein., Conclusion: The c.893G>A (p.Gly298Glu) mutation in the LBR gene probably underlies the PHA in this pedigree and has enriched the spectrum of LBR gene mutations.

Objective: To report on the result of thalassemia screening and genetic diagnosis for pregnant women from Guiyang region., Methods: Prenatal screening for thalassemia was carried out based on erythrocyte parameters and hemoglobin electrophoresis. Single-tube multiplex GAP-PCR and PCR-reverse dot blot hybridization were performed on suspected cases to identify common alpha- and beta- thalassemia mutations, and direct sequencing was used for identifying rare mutations., Results: Among 13 738 pregnant women, 1745 (12.70%) were suspected as thalassemia. In terms of native place, the provinces with highest screening-positive rates were Guangxi, Guangdong, Jiangxi and Guizhou. And the ethnic groups with highest screening-positive rates were Zhuang, Li, and Buyi. Among 801 women subjected to genetic testing, 457 (57.05%) were diagnosed with thalassemia. In total 9 genotypes of alpha- thalassemia were detected, with the most common genotypes being -- SEA /alpha alpha (63.35%), - alpha 3.7 /alpha alpha (19.37%) and - alpha 4.2 /alpha alpha (8.90%). Eleven genotypes of beta- thalassemia were detected, with the most common genotypes being CD17/N (42.91%), CD41-42/N (32.46%) and IVS-II-654/N (11.94%). Two cases were detected with rare beta-thalassemia mutations (CD54-58/N and IVS-I-130/N)., Conclusion: The screening-positive rate of thalassemia among pregnant women in Guiyang region is relatively high. The rates have shown substantial difference in terms of native place and ethnic group. Thalassemia-related mutations in Guizhou region have a diverse spectrum, which showed certain difference from those of other regions.

Objective: To identify potential mutation of TRAPPC2 gene in a Chinese family affected with X-linked spondyloepiphyseal dysplasia tarda (X-SEDL), and explore its underlying molecular mechanism., Methods: Peripheral blood samples were collected from 32 members of the family and 50 healthy adults to extract genomic DNA. DNA sequences of exons 3 to 6 and their exon/intron boundaries were amplified with PCR amplification. Direct bi-directional sequencing analysis was performed on the PCR products. The sequences were aligned to the reference sequences from the GenBank to determine mutation site and type., Results: A nucleotide substitution of the splice-donor in TRAPPC2 intron 3, c.93+5G>A, was detected in the proband, but no sequence change was detected in TRAPPC2 exons 3 to 6. All of the 6 male patients and 8 female carriers from the family were detected to have carried this mutation. The same mutation was not found in the remaining 18 family members with a normal phenotype and 50 healthy controls., Conclusion: We have detected a c.93+5G>A mutation in the TRAPPC2 gene in a Chinese family affected with X-SEDL. Our results have expanded the spectrum of TRAPPC2 mutations and is helpful for presymptomatic and prenatal diagnoses of this disease.

Objective: To investigate the spectrum of β -thalassemia mutations in Guizhou Province., Methods: For 542 individuals suspected to have β -thalassemia by decreased mean corpuscular volume (MCV) and corpuscle hemoglobin (MCH) by routine blood test and hemoglobin electrophoresis, reverse dot blot hybridization (RDB) was performed to detect 17 known β -thalassemia mutations, including 8 common and 9 rare mutations. For cases where no mutation was identified, the entire human β -globin gene was screened to find other rare mutations. The distribution and frequencies of detected β -thalassemia mutations were then analyzed., Results: A total of 460 individuals were diagnosed as β -thalassemia by DNA analysis, which included 352 heterozygotes, 67 compound heterozygotes and 41 mutant homozygotes. A total of 12 β -thalassemia mutations were detected in these individuals. The mutations have ranked from high to low frequency as: CD17 (40.74%), CD41-42 (33.69%), IVS-II-654 (13.76%), -28 (3.70%), β E (3.35%), CD71-72(1.94%), CD43 (1.06%), IVS-I-1 (0.71%), CD27-28 (0.35%), -29(0.35%), CAP (0.18%), and CD121 (0.18%). The former six mutations have accounted for 97.18% of all. CD121 (GAA> TAA) detected from a heterozygote, as a dominant mutation, has been firstly found in the Chinese population., Conclusion: The spectrum of β -thalassemia in Guizhou Province showed certain distinct characteristics, with CD17 being the most common mutation. The newly discovered mutation of CD121 has expanded the spectrum of β -thalassemia in Chinese population. Our result may provide valuable information for the prevention and control of β -thalassemia in Guizhou.

Objective: To investigate the association between the apolipoprotein E (apoE) gene polymorphism and the dose for warfarin individual maintenance., Methods: The genotypes of 249 patients with warfarin treatment in maintenance doses were determined by PCR/DHPLC assay. The doses for warfarin maintenance were compared among patients with different genotypes., Results: In the total of 249 patients, the frequencies of 2/ε2, ε2/ε3, ε2/ε4, ε3/ε3, ε3/ε4, ε4/ε4 genotype were 1.20%, 15.66%, 1.80%, 72.29%, 9.24%, 0.80%, respectively; the allele frequencies of ε2, ε3, ε4 were 9.44%, 84.74%, 5.82%, respectively. The warfarin dose of group ε2 (ε2/ε2, ε2/ε3) was (3.24 ± 1.36) mg/d, slightly higher than that of group ε3 (ε3/ε3, 2.91 ± 1.14 mg/d) or group ε4 [ε4/ε4, ε3/ε4, (2.98 ± 1.05) mg/d], but the difference of the warfarin doses among the 3 groups did not reach statistical significance (F=1.848,P>0.05)., Conclusion: ApoE polymorphism may be not a major genetic factor that influences the individual dose for warfarin maintenance.