The ester derivatives obtained by C-ring modification of podophyllotoxin-induced apoptosis and inhibited proliferation in Hemangioma Endothelial Cells via downregulation of PI3K/Akt signaling pathway

Infantile hemangioma (IH) is a common benign endothelial cell tumor in infants and young children, sometimes accompanied by potential complications, and may develop into malignant tumors. Hemangioma endothelial cells (HemECs) are one of the main components of IH. Podophyllotoxin (PPT) has been reported to have many pharmacological activities, especially anti-tumor, but its high toxicity, poor water solubility, and serious gastrointestinal side effects limit its clinical application. In this study, we have designed and synthesized 20 ester derivatives by introducing Boc-amino acids or organic acids at the C-4 position of podophyllotoxin through esterification reactions. The cytotoxicity of these compounds was evaluated on HemECs. Changes in cell proliferation and apoptotic signaling pathways were studied by DAPI staining, colony formation assay, migration assay, measurement of reactive oxygen species (ROS) levels flow cytometry, and Western blot analysis. We found that eight of the compounds were more potent than PPT. Of these, compound V-31 was the most active (IC 50 = 0.079 ± 0.0049 µM). Further research indicated that compound V-31 inhibited its proliferation and migration, increased the level of ROS in cells, and induced apoptosis by downregulating p-PI3K, p-Akt, and Bcl-2, and upregulating cleaved caspase-3 and Bax. Our research provides the first insight into the application of PPT derivatives in HemECs, may provide an effective medicine for IH treatment.