ABSTRACT
Objective:To evaluate the effect of laser irradiation on related growth factors in and apoptosis of in vitro cultured infantile hemangioma endothelial cells. Methods:Cultured infantile hemangioma endothelial cells were divided into 3 groups: intense pulsed light (IPL) group irradiated with IPL at a dose of 23 J/cm 2 for 1 session, laser group irradiated with 1 064-nm Nd:YAG laser at a dose of 90 J/cm 2 for 1 session, control group receiving no irradiation. On days 1, 3 and 7 after irradiation, RT-PCR was performed to measure the mRNA expression of vascular endothelial growth factor (VEGF) , VEGF receptor 2 (VEGFR-2) and basic fibroblast growth factor (bFGF) , and Western blot analysis to determine VEGFR-2 protein expression, enzyme-linked immunosorbent assay to detect the levels of VEGF and bFGF in the culture supernatant, and flow cytometry to detect cell apoptosis. Results:Compared with the control group, the laser group showed significantly decreased mRNA expression of VEGF (0.363±0.021 vs. 1.000±0.023, P< 0.001) , VEGFR-2 (0.483±0.017 vs. 1.001±0.031, P=0.001) and bFGF (0.402±0.040 vs. 1.000±0.004, P< 0.001) , decreased VEGFR-2 protein expression (0.332±0.055 vs. 0.768±0.096, P< 0.05) , decreased levels of VEGF (69.389±24.179 ng/L vs. 334.506±13.084 ng/L, P< 0.001) and bFGF (2.386±0.151 ng/L vs. 9.165±0.232 ng/L, P< 0.001) in the culture supernatant, but significantly increased apoptosis rate (18.413%±2.654% vs. 4.300%±0.036%, P< 0.01) on day 7 after irradiation. Compared with the control group, the IPL group also showed significantly decreased mRNA expression of VEGF (0.436±0.041 vs. 1.000±0.023, P< 0.05) , VEGFR-2 (0.493±0.037 vs. 1.001±0.031, P< 0.05) and bFGF (0.490±0.044 vs. 1.000±0.004, P< 0.05) , decreased VEGFR-2 protein expression (0.406±0.037 vs. 0.768±0.096, P< 0.05) , decreased levels of VEGF (128.858±6.063 ng/L vs. 334.506±13.084 ng/L, P< 0.001) and bFGF (2.723±0.471 ng/L vs. 9.165±0.232 ng/L, P< 0.001) in the culture supernatant, but significantly increased apoptosis rate (16.597%±1.877% vs. 4.300%±0.036%, P< 0.01) on day 7 after irradiation. Conclusion:The 1 064-nm Nd:YAG laser may exert a therapeutic effect on hemangioma by inhibiting hemangioma endothelial cells via regulating key factors on the VEGF/VEGFR-2 signaling pathway and cell apoptosis.