Proteomic and miRNA profiling of radon-induced skin damage in mice: FASN regulated by miRNAs.

Radon is a naturally occurring radioactive gas and considered as a serious carcinogen to humans. Continuous radioactive decay of this gas emits high-energy alpha particles. Long-term radon exposure induces oxidative stress and inflammatory response, which results in chronic lung diseases. However, biological effects after radon exposure in other organs have been rarely reported. As the outermost organ of the human body, the skin suffers from environmental damage to agents such as air pollution. Epidemiological studies indicated that areas with high level of radon had a high incidence of skin cancer. However, whether radon exposure induces skin damage has not been reported yet. In this study, we established a radon-exposed mouse model and found that radon exposure affected the structure of skin tissues, which was manifested by inflammatory cell infiltration and skin atrophy. Using proteomic approach, we found 45 preferentially expressed proteins in 60 Working Level Months (WLM) group and 314 preferentially expressed proteins in 120 WLM group from radon-exposed skin tissues. Through microRNA (miRNA) sequencing profiling analysis, 57 dysregulated miRNAs were screened between the control and radon-treated mouse skin. By integrating the dysregulated proteins and miRNAs, radon-induced fatty acid synthase (FASN) was investigated in greater detail. Results showed that FASN was regulated by miR-206-3p and miR-378a-3p and involved in the pathogenesis of radon-induced skin damage. Overexpression of FASN inhibited the proliferation, and induced in WS1 cells. Our present findings illustrate the molecular change during radon-induced skin damage and the potential role of FASN during this process.