Browsing by Author "Yu, Miao"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Hydroxyurea differentially modulates activator and repressors of γ-globin gene in erythroblasts of responsive and non-responsive patients with sickle cell disease in correlation with Index of Hydroxyurea Responsiveness
    (Ferrata Storti Foundation, 2017-12) Zhu, Xingguo; Hu, Tianxiang; Ho, Meng Hsuan; Wang, Yongchao; Yu, Miao; Patel, Niren; Pi, Wenhu; Choi, Jeong-Hyeon; Xu, Hongyan; Ganapathy, Vadivel; Kutlar, Ferdane; Kutlar, Abdullah; Tuan, Dorothy; Radiation Oncology, School of Medicine
    Hydroxyurea (HU), the first of two drugs approved by the US Food and Drug Administration for treating patients with sickle cell disease (SCD), produces anti-sickling effect by re-activating fetal γ-globin gene to enhance production of fetal hemoglobin. However, approximately 30% of the patients do not respond to HU therapy. The molecular basis of non-responsiveness to HU is not clearly understood. To address this question, we examined HU-induced changes in the RNA and protein levels of transcription factors NF-Y, GATA-1, -2, BCL11A, TR4, MYB and NF-E4 that assemble the γ-globin promoter complex and regulate transcription of γ-globin gene. In erythroblasts cultured from peripheral blood CD34+ cells of patients with SCD, we found that HU-induced changes in the protein but not the RNA levels of activator GATA-2 and repressors GATA-1, BCL11A and TR4 correlated with HU-induced changes in fetal hemoglobin (HbF) levels in the peripheral blood of HU high and low responders. However, HU did not significantly induce changes in the protein or RNA levels of activators NF-Y and NF-E4. Based on HU-induced changes in the protein levels of GATA-2, -1 and BCL11A, we calculated an Index of Hydroxyurea Responsiveness (IndexHU-3). Compared to the HU-induced fold changes in the individual transcription factor protein levels, the numerical values of IndexHU-3 statistically correlated best with the HU-induced peripheral blood HbF levels of the patients. Thus, IndexHU-3 can serve as an appropriate indicator for inherent HU responsiveness of patients with SCD.
  • Thumbnail Image
    Item
    Tet2 loss leads to hypermutagenicity in haematopoietic stem/progenitor cells
    (SpringerNature, 2017-04-25) Pan, Feng; Wingo, Thomas S.; Zhao, Zhigang; Gao, Rui; Makishima, Hideki; Qu, Guangbo; lin, Li; Yu, Miao; Ortega, Janice R.; Wang, Jiapeng; Nazha, Aziz; Chen, Li; Yao, Bing; Liu, Can; Chen, Shi; Weeks, Ophelia; Ni, Hongyu; Phillips, Brittany Lynn; Huang, Suming; Wang, Jianlong; He, Chuan; Li, Guo-Min; Radivoyevitch, Tomas; Aifantis, Iannis; Maciejewski, Jaroslaw P.; Yang, Feng-Chun; Jin, Peng; Xu, Mingjiang; Department of Pediatrics, School of Medicine
    TET2 is a dioxygenase that catalyses multiple steps of 5-methylcytosine oxidation. Although TET2 mutations frequently occur in various types of haematological malignancies, the mechanism by which they increase risk for these cancers remains poorly understood. Here we show that Tet2-/- mice develop spontaneous myeloid, T- and B-cell malignancies after long latencies. Exome sequencing of Tet2-/- tumours reveals accumulation of numerous mutations, including Apc, Nf1, Flt3, Cbl, Notch1 and Mll2, which are recurrently deleted/mutated in human haematological malignancies. Single-cell-targeted sequencing of wild-type and premalignant Tet2-/- Lin-c-Kit+ cells shows higher mutation frequencies in Tet2-/- cells. We further show that the increased mutational burden is particularly high at genomic sites that gained 5-hydroxymethylcytosine, where TET2 normally binds. Furthermore, TET2-mutated myeloid malignancy patients have significantly more mutational events than patients with wild-type TET2. Thus, Tet2 loss leads to hypermutagenicity in haematopoietic stem/progenitor cells, suggesting a novel TET2 loss-mediated mechanism of haematological malignancy pathogenesis.
  • Thumbnail Image
    Item
    Transgenic ferret models define pulmonary ionocyte diversity and function
    (Springer Nature, 2023) Yuan, Feng; Gasser, Grace N.; Lemire, Evan; Montoro, Daniel T.; Jagadeesh, Karthik; Zhang, Yan; Duan, Yifan; Levlev, Vitaly; Wells, Kristen L.; Rotti, Pavana G.; Shahin, Weam; Winter, Michael; Rosen, Bradley H.; Evans, Idil; Cai, Qian; Yu, Miao; Walsh, Susan A.; Acevedo, Michael R.; Pandya, Darpan N.; Akurathi, Vamsidhar; Dick, David W.; Wadas, Thaddeus J.; Joo, Nam Soo; Wine, Jeffrey J.; Birket, Susan; Fernandez, Courtney M.; Leung, Hui Min; Tearney, Guillermo J.; Verkman, Alan S.; Haggie, Peter M.; Scott, Kathleen; Bartels, Douglas; Meyerholz, David K.; Rowe, Steven M.; Liu, Xiaoming; Yan, Ziying; Haber, Adam L.; Sun, Xingshen; Engelhardt, John F.; Medicine, School of Medicine
    Speciation leads to adaptive changes in organ cellular physiology and creates challenges for studying rare cell-type functions that diverge between humans and mice. Rare cystic fibrosis transmembrane conductance regulator (CFTR)-rich pulmonary ionocytes exist throughout the cartilaginous airways of humans1,2, but limited presence and divergent biology in the proximal trachea of mice has prevented the use of traditional transgenic models to elucidate ionocyte functions in the airway. Here we describe the creation and use of conditional genetic ferret models to dissect pulmonary ionocyte biology and function by enabling ionocyte lineage tracing (FOXI1-CreERT2::ROSA-TG), ionocyte ablation (FOXI1-KO) and ionocyte-specific deletion of CFTR (FOXI1-CreERT2::CFTRL/L). By comparing these models with cystic fibrosis ferrets3,4, we demonstrate that ionocytes control airway surface liquid absorption, secretion, pH and mucus viscosity-leading to reduced airway surface liquid volume and impaired mucociliary clearance in cystic fibrosis, FOXI1-KO and FOXI1-CreERT2::CFTRL/L ferrets. These processes are regulated by CFTR-dependent ionocyte transport of Cl- and HCO3-. Single-cell transcriptomics and in vivo lineage tracing revealed three subtypes of pulmonary ionocytes and a FOXI1-lineage common rare cell progenitor for ionocytes, tuft cells and neuroendocrine cells during airway development. Thus, rare pulmonary ionocytes perform critical CFTR-dependent functions in the proximal airway that are hallmark features of cystic fibrosis airway disease. These studies provide a road map for using conditional genetics in the first non-rodent mammal to address gene function, cell biology and disease processes that have greater evolutionary conservation between humans and ferrets.