Endothelial GNAQ p.R183Q mutation confers hemoporfin-mediated photodynamic therapy resistance and drives pathological angiogenesis via the angiopoietin-2/TIE2/PI3K/AKT pathway

Hemoporfin-mediated photodynamic therapy (HMME-PDT) has demonstrated significant advantages in the treatment of Port-wine stains (PWSs). However, the therapeutic efficacy of HMME-PDT remains suboptimal in a subset of patients. Somatic mosaic mutations in <i>GNAQ</i> (c.548G>A, p. R183Q) are frequently detected in endothelial cells (ECs) of lesions and represent a common pathogenic mechanism. In this study, we successfully established an <i>in vitro</i> model of PWSs by introducing the <i>GNAQ</i> p. R183Q mutation into HUVECs using lentiviral infection. Our results revealed that <i>GNAQ</i> p. R183Q mutation enhanced ECs proliferation, migration, and angiogenesis. Moreover, the mutation augmented anti-apoptotic mechanisms, thereby conferring heightened resistance to HMME-PDT-induced apoptosis. Residual angiogenic activity persisted following HMME-PDT treatment. These effects are likely mediated by activation of the angiopoietin-2 (ANGPT2)/TIE2/PI3K/AKT signaling axis. Knockdown of ANGPT2 partly reversed these phenotypic alterations and significantly enhanced the efficacy of HMME-PDT. The combination of HMME-PDT with anti-ANGPT2 therapy holds promise for enhancing therapeutic efficacy, suppressing pathological angiogenesis, and ameliorating the clinical manifestations of PWSs.