IL-17-mediated inflammation promotes cigarette smoke-induced genomic instability

Abstract

Abstract Background Chronic inflammation has been regarded as a risk factor for the onset and progression of human cancer, but the critical molecular mechanisms underlying this pathological process has yet to be elucidated. Methods In this study, we investigated whether interleukin (IL)-17-mediated inflammation was involved in cigarette smoke-induced genomic instability. Results Higher levels of both IL-17 and the DNA damage response (DDR) were found in the lung tissue of smokers than that of non-smokers. Similarly, elevated levels of IL-17 and the DDR were observed in mice after cigarette smoke exposure, and a positive correlation was observed between IL-17 expression and the DDR. In line with these observations, the DDR in the mouse lung was diminished in IL-17 KO when exposed to cigarette smoke. Besides, the treatment of human bronchial epithelium cells with IL-17 led to increased levels of the DDR and chromosome breakage. Conclusions These results suggest that cigarette smoke induces genomic instability at least partially through IL-17 mediated inflammation, implying that IL-17 could play an important role in the development of lung cancer.