Evaluation of Biological Effects and Transcriptome Changes Induced by LED‐Based Narrow‐Band UVB Phototherapy

ABSTRACT Ultraviolet (UV), particularly UVB, is widely used in the treatment of skin diseases including psoriasis, atopic dermatitis, vitiligo, mycosis fungoides and pruritus. Recently, there has been a trend of replacing broad‐band UVB (BB‐UVB) units with narrow‐band UVB (NB‐UVB), as studies have demonstrated that NB‐UVB is more efficacious in the treatment of psoriasis. The purpose of this study is to evaluate the biological effects and transcriptome changes induced by light‐emitting diode‐based NB‐UVB (NB‐UVB LED) phototherapy. Cell viability and the cell migration ability were significantly decreased posttreatment, as well as apoptosis and ROS levels were remarkably increased. NB‐UVB‐induced S phase arrest was observed 12 h postirradiation. Bioinformatics analysis of transcriptome sequencing data revealed that NB‐UVB LED irradiation induced dose‐depended changes in multiple key signaling pathways, such as PI3K and cytoskeletal‐related pathways. The depolymerization of cytoskeleton induced by NB‐UVB was observed 24 h posttreatment. In addition, the expression levels of cytoskeleton‐related proteins FN1, ITGB4, ITGA1, RAC2 and DOCK1 decreased significantly 12 h after irradiation. Our results indicated that NB‐UVB LED may serve as a novel option for the development of NB‐UVB phototherapy devices. Light‐emitting diode‐based narrow‐band ultraviolet B (NB‐UVB LED) is a prospective substitution of UVB lamp tube in clinical applications. Herein, biological effects, transcriptome sequencing and bioinformatics analysis were conducted to explore the possible pathways involved in the NB‐UVB LED phototherapy. NB‐UVB LED irradiation showed dose‐depended changes in multiple key signaling pathways, such as PI3K and cytoskeletal‐related pathways. The S‐phase arrest was observed, indicating the NB‐UVB LED may affect the cell cycle in a different way compared with other light sources. Also, the impairments of cytoskeleton were confirmed in morphology (via structured illumination microscopy), as well as protein and mRNA levels.