Potential molecular characteristics in situ in response to repetitive UVB irradiation.
BACKGROUND
To identify molecular characteristics in situ in response to repetitive UVB (ultraviolet-B) irradiation.


METHODS
Microarray data from the Gene Expression Omnibus were re-analyzed to identify DEGs (differentially expressed genes) between UVB-irradiated and non-irradiated skin biopsies. Enrichment and annotation analyses were performed respectively using DAVID, and TSGene and TAG databases. PPIs (protein-protein interactions) were analyzed using STRING, and miRNAs (microRNAs) and TFs (transcription factors) were predicted separately by miRNA-related databases and ENCODE. Accordingly, the PPI network and regulatory networks were visualized using Cytoscape, and they were merged together to obtain an integrated network for mining densely connected modules.


RESULTS
Altogether, 151 up- and 64 down-regulated genes were identified between UVB-irradiated and non-irradiated skin biopsies, among which down-regulated DNAJB4 and SLIT2 were annotated as tumor-suppressors and up-regulated KIT was annotated as an oncogene. The up-regulated DEGs were significantly enriched in biological processes related to pigmentation (DCT, SOX10, TYRP1, TYR, MLPH, KIT and GPR143), while the down-regulated DEGs were dramatically related to haemopoiesis and the immune system (GPR183, INHBA, PTPRC, PLEK, CD8A and IKZF1). Furthermore, many miRNAs were screened for the DEGs, including miR-206 and miR-496 targeting KIT, miR-184 targeting DCT, and highly significant miR-337-5p, miR-21 and miR-16. Additionally, TFs were identified for the DEGs, among which PAX5 and HNF4A targeted MLPH and GPR143, respectively, while BATF, SPI1 and EP300 jointly target GPR183, PTPRC and PLEK.


CONCLUSIONS
The pigmentation and immune system implicated by DEGs, miRNAs and TFs might be important molecular mechanisms in response to UVB irradiation.
Department of Dermatology, Nanjing First Hospital, Nanjing Medical University, 68 Changle Road, Nanjing, Jiangsu, 210006, China. 115366110132@163.com.
Wenqi
W
Chen
Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China.
Jinhai
J
Zhang
D000328:Adult; D005260:Female; D020869:Gene Expression Profiling; D053263:Gene Regulatory Networks; D006801:Humans; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D012867:Skin / Q000528:radiation effects*; D059467:Transcriptome; D014466:Ultraviolet Rays / Q000009:adverse effects*
Bioinformatics methods; In situ; Molecular characteristics; Re-analysis of microarray data; Repetitive UVB irradiation