Effect of PI3K/mTOR dual-target inhibitor WX390 on adipose-derived stem cells isolated from facial infiltrating lipomatosis

Facial infiltrating lipomatosis (FIL) is a congenital disorder characterized by unilateral facial enlargement. Although next-generation sequencing has revealed that the pathogenesis of FIL is associated with phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) mutations, the underlying molecular mechanisms remain undetermined. We found that the adipose tissue in FIL patients demonstrated tissue infiltration accompanied by adipocytes hypertrophy and increased lipid accumulation. All FIL-ADSCs harboured PIK3CA mutations. Compared to ADSCs obtained from normal subcutaneous adipose tissue, FIL-ADSCs exhibited a greater capacity for adipogenesis. Suppression of PIK3CA resulted in a reduction in the adipogenic potential of FIL-ADSCs. Furthermore, WX390, a novel dual-target PI3K/mTOR inhibitor, was found to impede PIK3CA-mediated adipogenesis both in vivo and in vitro. RNA-seq revealed that the expression of transient receptor potential vanilloid subtype 1 (TRPV1) was upregulated after PI3K pathway inhibition, and overexpression and activation of TRPV1 both inhibited adipogenesis of FIL-ADSCs. Our study showed that PIK3CA mutations promoted adipogenesis in FIL-ADSCs and that this effect was achieved by suppressing the expression of TPRV1. Pathogenesis experiments suggested that WX390 may serve as an agent for the treatment of FIL.