Extensive genetic diversity of severe fever with thrombocytopenia syndrome virus circulating in Hubei Province, China, 2018-2022.

Severe fever with thrombocytopenia syndrome virus (SFTSV), an etiological agent causing febrile human disease was identified as an emerging tick-borne bunyavirus. The clinical disease characteristics and case fatality rates of SFTSV may vary across distinct regions and among different variant genotypes. From 2018 to 2022, we surveyed and recruited 202 severe fever with thrombocytopenia syndrome (SFTS) patients in Hubei Province, a high-incidence area of the epidemic, and conducted timely and systematic research on the disease characteristics, SFTSV diversity, and the correlation between virus genome variation and clinical diseases. Our study identified at least 6 genotypes of SFTSV prevalent in Hubei Province based on the analysis of the S, M, and L genome sequences of 88 virus strains. Strikingly, the dominant genotype of SFTSV was found to change during the years, indicating a dynamic shift in viral genetic diversity in the region. Phylogenetic analysis revealed the genetic exchange of Hubei SFTSV strains was relatively frequent, including 3 reassortment strains and 8 recombination strains. Despite the limited sample size, SFTSV C1 genotype may be associated with higher mortality compared to the other four genotypes, and the serum amyloid A (SAA) level, an inflammatory biomarker, was significantly elevated in these patients. Overall, our data summarize the disease characteristics of SFTSV in Hubei Province, highlight the profound changes in viral genetic diversity, and indicate the need for in-depth monitoring and exploration of the relationship between viral mutations and disease severity.

Dual function of MAZ mediated by FOXF2 in basal-like breast cancer: Promotion of proliferation and suppression of progression.

Myc-associated zinc finger protein (MAZ) is a transcription factor with C2H2-type zinc-finger motifs that can bind GC-rich cis-elements. MAZ activates the transcription of some cancer-related genes and represses that of others, suggesting that changes in MAZ expression may play different roles in the development and progression of different types or subtypes of cancers depending on its target genes. However, the functions and mechanisms of MAZ in regulating the carcinogenesis and progression of breast cancer have remained unclear. In the current study, we show that MAZ performs dual function in basal-like breast cancer (BLBC): suppression of aggressiveness and promotion of proliferation. Forkhead box F2 (FOXF2) is a novel transcription target of MAZ and mediates the functions of MAZ. The MAZ mRNA level, particularly in combination with the FOXF2 mRNA level, may serve as a prognostic marker for BLBC patients. Our results indicate that the dual function of the MAZ-FOXF2 axis reflect the pleiotropic nature of multifunctional transcription factors in regulating the different stages of cancer development and progression, which could lead to the complexity of cancer diagnosis and treatment.

DNA Methylation Affects the SP1-regulated Transcription of FOXF2 in Breast Cancer Cells.

FOXF2 (forkhead box F2) is a mesenchyme-specific transcription factor that plays a critical role in tissue homeostasis through the maintenance of epithelial polarity. In a previous study, we demonstrated that FOXF2 is specifically expressed in basal-like breast cancer (BLBC) cells and functions as an epithelial-mesenchymal transition suppressor. FOXF2 deficiency enhances the metastatic ability of BLBC cells through activation of the epithelial-mesenchymal transition program, but reduces cell proliferation. In this study, we demonstrate that CpG island methylation of the FOXF2 proximal promoter region is involved in the regulatory mechanism of the subtype-specific expression of FOXF2 in breast cancer cells. DNMT1, DNMT3A, and DNMT3B commonly or individually contributed to this DNA methylation in different breast cancer cells. SP1 regulated the transcriptional activity of FOXF2 through direct binding to the proximal promoter region, whereas this binding was abrogated through DNA methylation. FOXF2 mediated the SP1-regulated suppression of progression and promotion of proliferation of non-methylated BLBC cells. Thus, we conclude that the subtype-specific expression and function of FOXF2 in breast cancer cells are regulated through the combined effects of DNA methylation and SP1 transcriptional regulation.

Research on the effects of PIAS3 expression on the invasion of glioma TJ905 cells / 中华外科杂志

<p><b>OBJECTIVES</b>To investigate the function and possible mechanisms of PIAS3 expression on the invasion of TJ905 cells.</p><p><b>METHODS</b>PIAS3 overexpression vectors were constructed and PIAS3 siRNA were chemically synthesized, which were separately transfected into TJ905 cells for upregulation or downregulation of PIAS3 expression levels in TJ905 cells. After that, the invasive effects of TJ905 cells were measured by Transwell assay, and the expression of PIAS3, tissue inhibitor of metalloproteinases (TIMP)3, matrix metalloprotease (MMP)-2, and MMP-9 were identified by Western blot.</p><p><b>RESULTS</b>In vitro transfection efficiency of plasmids and oligonucleotides were separately 85.3% ± 3.1% and 95.1% ± 2.9%. PIAS3 overexpression plasmid transfection in vitro could effectively improve the expression of PIAS3 protein in TJ905 cells and inhibit the invasion of TJ905 cells (P < 0.05), and cell penetration ratio reduced from 87.9% ± 9.3% to 37.3% ± 7.9% compared with control group, while it upregulated TIMP3 and downregulated MMP-2, MMP-9 protein expression (P < 0.05); PIAS3 siRNA transfection could inhibit the PIAS3 protein expression of TJ905 cells and promote the invasion of TJ905 cells (P < 0.05), and cell penetration ratio increased from 83.9% ± 7.1% to 93.2% ± 3.1% compared with control group, while it downregulated TIMP3 and upregulated MMP-2, MMP-9 protein expression (P < 0.05).</p><p><b>CONCLUSION</b>PIAS3 expression is closely related to the invasion properties of glioma TJ905 cells.</p>