Accordingly, in PAECs from IPAH patients (Figure 7C) and in BMPR2-silenced PAECs (Figure 7D), DLL4 not only induced PPARG transcription, but also increased mRNA expression of several PPARγ target genes (FABP4, CYP1A1, PGK1 and HK1). Here, DLL4 is linked to idiopathic pulmonary arterial hypertension.