SSc  systemic sclerosis  SRC  scleroderma renal crisis  PAH  pulmonary arterial hypertension  SMR  standardized mortality ratio  DNMTs  DNA methyltransferases  SAM  S-adenosyl-methionine  5mC  5-methylcytosine  MBD  methyl-CpG-binding domain  Tet  ten–eleven translocation  HATs  histone acetyltransferases  HDACs  histone deacetylases  MiRNAs  microRNAs  MZ  monozygotic  DZ  dizygotic  MVECs  microvascular endothelial cells  FBs  fibroblasts  JAMs  junctional adhesion molecules  CTGF  connective tissue growth facto  TGF-β  transforming growth factor beta  CCN2  connective tissue growth factor  Fli1  Friend leukemia integration-1  TF  transcription factor  PECAM  platelet/endothelial cell adhesion molecule  PDGF  platelet derived growth factor  S1P1  sphingosin 1 phosphate  CXCL5  CXC chemokine ligand-5  BMPs  bone morphogenetic proteins  BMPRII  bone morphogenetic protein type II receptor  ET-1  endotheline-1  uPA  urokinase-type plasminogen activator  MBD  methyl-CpG-binding domain protein  ICAM  intercellular adhesion molecule  KLF5  Kruppel-like factor 5  Tregs  regulatory T cells  Runx1  Runt-related transcription factor 1  FOXP3  forkhead box protein 3 gene  ECM  extra cellular matrix  PDGF  platelet-derived growth factor  dSSc  diffuse systemic sclerosis  lSSc  limited systemic sclerosis  PCAF  protein-associated factor  Egr-1  early growth response 1  DDR2  discoidin domain receptor 2  TAB1  TGF-β activated kinase 1 binding protein 1  BAFF  B cell-activating factor  TSP-2  thrombospondin-2  MRTSS  Modified Rodnan total skin score  SDAI  Valentini scleroderma disease activity index  HC  healthy controls  SLE  systemic lupus erythematosus  SSD  scleroderma spectrum disorder  MTX  methylaminopterin  CYC  cyclophosphamide  MMF  mycophenolate mofetil  ACE  angiotensin converting enzyme  NO  nitric oxide  Systemic sclerosis  Epigenetic mechanisms  Biomarker  Therapy