Myosin 1b Inhibits the Phenotype of HemECs to Affect the Progression of Infantile Hemangiomas.

PURPOSE: To investigate the role of myosin 1b (Myo1b) in infantile hemangiomas (IHs). PATIENTS AND METHODS: The expression of Myo1b in IHs and normal skin tissues was evaluated using immunohistochemical techniques. Expression of Myo1b in hemangioma endothelial cells (HemECs) was detected using quantitative real-time polymerase chain reaction and Western blotting techniques. The effects of Myo1b on cell proliferation, invasion, tube formation and other biological characteristics were analyzed. A mouse model was established to observe the inhibitory effects of Myo1b in vivo. Protein expression of peroxisome proliferator-activated receptor-gamma (PPARγ) and glucose transporter 1 protein (Glut-1) in a Myo1b knockdown HemECs was detected using Western blot. RESULTS: Myo1b was highly expressed in the proliferative stage of IHs, and promoted proliferation, invasion, and angiogenesis in vitro. Mouse models further demonstrated that Myo1b inhibited proliferation and angiogenesis of IHs. Knockdown of Myo1b inhibited Glut-1 activity, promoted expression of PPARγ transcription factor. CONCLUSION: Myo1b has a pro-tumor effect on IHs, knockdown of Myo1b facilitated progression of the proliferating to involution phase of IHs. Therefore, Myo1b is expected to serve as a new target for the treatment of IHs.