In two studies with heterocellular tissues containing human CF and inducible pluripotent stem cell-derived cardiomyocytes (iPSC-CM), PFD consistently reduced the expression of the fibrosis-associated gene periostin (POSTN) (Mastikhina et al. 2020; Bracco Gartner et al. 2022). Here, POSTN is linked to polyostotic fibrous dysplasia.