The effect of 595 nm pulsed dye laser on connective tissue growth factor (CTGF) expression in cultured keloid fibroblasts.

OBJECTIVE: To investigate the effect of pulsed dye laser (PDL 595 nm) on the proliferation and expression of connective tissue growth factor (CTGF) in cultured keloid fibroblasts.

MATERIALS AND METHODS: Cultured keloid fibroblasts were exposed to pulsed dye laser irradiation at fluences of 6, 8, and 10 J/cm(2) , with pulse durations of 1.5, 3, and 10 ms. The viability of keloid fibroblasts was measured with CCK-8 at 72, 24, and 12 hours prior to irradiation. Subsequently, viability was measured at 12, 24, and 72 hours post-irradiation. Additionally, the fibroblast cell cycle and apoptosis rate were measured by flow cytometry. Finally, keloid fibroblasts underwent real-time polymerase chain reaction (PCR) and Western blot to investigate the CTGF mRNA and protein expression after PDL irradiation. The untreated cultured keloid fibroblasts served as controls.

RESULTS: The proliferation of keloid fibroblasts was significantly inhibited after PDL irradiation. Both CTGF mRNA and protein expression were significantly down-regulated in 1.5, 3, and 10 ms pulse duration groups, in a dose dependent manner (P < 0.05). However, there was no statistically significant difference between groups of different pulse duration in 6, 8, and 10 J/cm(2) fluence ranges (P > 0.05).

CONCLUSIONS: Within certain fluence ranges, pulsed dye laser can effectively suppress the growth of keloids and significantly down-regulate CTGF mRNA and CTGF expression.