Toll样受体与紫外线致皮肤光损伤及皮肤肿瘤

Toll-like receptors in ultraviolet radiation-induced skin damage and cancer

紫外线辐射可导致免疫抑制、DNA损伤及皮肤肿瘤的发生。Toll样受体是重要的模式识别受体，在机体天然免疫和获得性免疫中均起重要作用。Toll样受体在皮肤角质形成细胞、朗格汉斯细胞、树突细胞、肥大细胞、成纤维细胞、黑素细胞中都有表达。激活Toll样受体相关信号通路可使与免疫应答相关的细胞因子、趋化因子、共刺激分子及黏附分子的表达增加。越来越多的研究表明，Toll样受体与紫外线辐射后细胞应答相关，以Toll样受体为靶标预防和治疗皮肤癌已愈来愈受到关注。

Ultraviolet （UV） irradiation can cause immune suppression, DNA damage and skin tumors. Toll-like receptors （TLRs）, as important pattern recognition receptors, play essential roles in both innate and adaptive immune responses, and are expressed on a variety of cell types in skin, including keratinocytes, Langerhans cells, dendritic ceils, mast ceils, fibroblasts and melanocytes. TLR activation can upregulate the expression of cytokines, chemokines, and costimulatory and adhesion molecules involved in innate and adaptive immune responses. Mounting evidences have suggested that TLRs are associated with cellular responses to UV exposure. In addition, there has been a growing interest in the targeting of TLRs for the prevention and treatment of skin cancer.