VEGFA and pulmonary arterial hypertension: Moreover, a number of transcription factors including members of the AP1 complex, STAT1, STAT4, RFX3, RFX4, GATA4 and GATA6 showed increased activity in PAH samples based on H3K27ac signal, whereas the VEGF target NOS3, the serotonin receptor HTR1BRC, and YAP1 enhancers showed a reduction in H3K27ac signal [78].