Regulation of DNA demethylation of STAT3 promoter in CD4+ T cells from aGVHD patients by HMGB1/GADD45A.
10.11817/j.issn.1672-7347.2018.09.002
- Author:
Yajing XU
1
;
Jing YANG
1
;
Yuanyuan ZHANG
1
;
Enyi LIU
1
;
Jie PENG
1
;
Xu CHEN
1
;
Fangping CHEN
1
;
Minyuan PENG
1
Author Information
1. Department of Hematology, Xiangya Hospital, Central South University, Changsha 410008, China.
- Publication Type:Journal Article
- MeSH:
CD4-Positive T-Lymphocytes;
Cell Cycle Proteins;
metabolism;
DNA Demethylation;
Gene Expression Regulation;
genetics;
Graft vs Host Disease;
genetics;
HMGB1 Protein;
metabolism;
Hematopoietic Stem Cell Transplantation;
Humans;
Nuclear Proteins;
metabolism;
Promoter Regions, Genetic;
genetics;
STAT3 Transcription Factor;
genetics;
metabolism
- From:
Journal of Central South University(Medical Sciences)
2018;43(9):937-944
- CountryChina
- Language:Chinese
-
Abstract:
To study the molecular mechanism for DNA hypomethylation of STAT3 promoter in CD4+ T cells from acute graft-versus-host disease (aGVHD) patients.
Methods: We collected CD4+ T cells from peripheral blood of 42 patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) from HLA-identical sibling donors. GADD45A expression level in CD4+ T cells was measured by real-time PCR and Western blot. The binding level between HMGB1 and GADD45A in CD4+ T cells was analyzed by co-immunoprecipitation, while the binding levels of HMGB1/GADD45A with STAT3 promoter were detected by chromatin immunoprecipitation-quantitative real-time PCR (ChIP-qPCR). After overexpression of HMGB1 and knockdown of GADD45A in normal CD4+ T cells, STAT3 expression and DNA methylation were measured by Western blot and bisulfite sequencing PCR, respectively.
Results: GADD45A expression was significantly up-regulated in patients with aGVHD compared with that in the patients without aGVHD. More HMGB1-GADD45A complexes were found in CD4+ T cells from patients with aGVHD compared with that in patients without aGVHD. The bindings of HMGB1/GADD45A with STAT3 promoter were significantly increased, and the binding levels of HMGB1/GADD45A were negatively correlated with STAT3 promoter DNA methylation. The expression of STAT3 was significantly reduced and the DNA methylation of STAT3 promoter was significantly increased in CD4+ T cells with overexpression of HMGB1 and knockdown of GADD45A compared with CD4+ T cells only with overexpression of HMGB1.
Conclusion: The increased expression of HMGB1/GADD45A plays an importent role in STAT3 promoter DNA hypomethylation, thereby promoting STAT3 expression in CD4+ T cells from aGVHD patients.
