To investigate the involvement of MAPKs in the modulation of Runx2 expression by HCS induction, human AF cells were treated with specific inhibitors for MAPKs (PD98059 for ERK, SP600125 for JNK, SB203580 for p38) for 1 h before and during HCS stimulation. The gene discussed is MAPK8; the disease is atrial fibrillation.