Ten million HCASMC cells per condition were crosslinked for 10 min with 1% formaldehyde. Cells were lysed for 10 min on ice, and nuclei were then lysed for 10 min on ice. Crosslinked chromatin was sheared for 3x5 min by sonication using a Bioruptor and pre-cleared with 10 µg anti-rabbit IgG pre-immune serum. TCF21 ChIP was performed overnight in IP dilution buffer using anti-TCF21 (Sigma-Aldrich, St. Louis, MA, USA, #HPA013189, Lot. No. R02939 (Ab1) or Abcam, Cambridge, UK, #ab49475, Lot No. 153899 (Ab2)) or anti-rabbit IgG respectively. JUN and JUND ChIP was performed with Santa Cruz Biotechnology sc-1694 and Santa Cruz Biotechnology sc-74 respectively. After reverse-crosslinking, RNaseA and proteinase K digestion, chromatin was cleaned up using the Qiagen PCR purification kit