Everolimus and sunitinib induce infantile hemangiomas cell apoptosis through P53 activation

Infantile hemangiomas (IH) are common vascular tumors in infants, yet their underlying mechanisms remain poorly understood. In this study, we isolated endothelial cells from IH and utilized hTERT and SV40 to establish an immortalized hemangioma-derived endothelial cell (iHemEC). We employed these iHemEC for in vitro drug screening and investigated the mechanisms of drug-induced inhibition of iHemEC via transcriptome sequencing, western blot analysis, and various cellular assays. We successfully established iHemEC that highly express VEGFR2, CD31, and GLUT-1, markers characteristic of endothelial cells. Screening of 18 putative working drugs were performed on iHemEC. Sunitinib, Elimusertib, HIF-1 inhibitor-4, Rebastinib, and Everolimus can inhibit iHemEC with lower IC50 than Propranolol and Rapamycin. We further performed transcriptome profiling in iHemEC upon Everolimus and Sunitinib intervention. GSEA showed that both drugs can significantly downregulate Hallmark of MYC target V1&V2, E2F Target and G2M Checkpoint which are all cell cycle related Hallmark. PI3K/AKT/mTOR pathway is only downregulated in Everolimus treated cells which is validated by western blot. Chromosome instability was found specifically in Sunitinib treated cells which was reported to cause DNA damage. DHR123 was used to detect DNA damage induced ROS and released extracellular ROS can only be observed in Sunitinib treated cells. Finally, P53 activation was observed in western blot, we found that Sunitinib can trigger P53 activation and BCL2 downregulation from 0.2 µM which is fifty times lower than Everolimus at 10 µM. Our study successfully developed an iHemEC line suitable for in vitro drug screening and mechanistic study. Everolimus and Sunitinib are two of working drugs and both drugs can induce P53 dependent apoptosis on iHemEC might through PI3K/AKT/mTOR inhibition and chromosome instability respectively. These findings provide a valuable basis for further research and potential clinical application in the treatment of IH.