Background and purpose:There are emerging evidences show that cytokines can mediate the expression and function of chemokines. CXC chemokine ligand 17 (CXCL17) is the latest member in CXC chemokine superfamily, which was identiifed in 2006. It may be involved in anti-tumor immune response. As a mucosal chemokine, CXCL17 was also proved to have anti-inlfammatory and anti-microbial effects. The purpose of this study was to ifgure out which cytokine can impact the expression of CXCL17. Methods:Quantitative real-time PCR (qRT-PCR) was used to detect the mRNA expression of CXCL17 in MCF-10A after cytokines stimulation, such as TNF-α, IL-1β, IFN-γand lipopolysaccharide (LPS). Western blot was used to detect the activation of the JAK-STAT pathway in MCF-10A after IFN-γinduction. Results:All tested cytokines can induce CXCL17 gene expression to varying degrees. However, the effect of IFN-γwas much more powerful by contrast with others. It can enhance the CXCL17 gene expression by about 100-fold. Western blot indicated that IFN-γcan stimulate the expression and phosphorylation of STAT1 in JAK-STAT pathway. Conclusion:Several cytokines can induce the expression of CXCL17 by breast epithelial cells, while IFN-γdramatically increased the expression of it via a JAK-STAT1-dependent pathway. CXCL17 may be the target gene of IFN-γ.%背景与目的：趋化因子在白细胞浸润、免疫调节和肿瘤转移等病理生理过程中发挥着广泛而重要的作用，但人们对其调控机制了解甚少。研究表明，细胞因子可刺激趋化因子的表达，从而发挥其生物学功能。CXC趋化因子配体17(CXC chemokine ligand 17，CXCL17)是2006年发现的CXC趋化因子中新的一员。CXCL17具有抗炎、抗菌、抗肿瘤免疫和促血管生成等作用。通过研究其上游调控机制可为其用于临床诊断与治疗提供线索。本研究旨在探讨何种细胞因子可以影响CXCL17的表达。方法：实时荧光定量PCR(quantitative real-time PCR，qRT-PCR)检测多种细胞因子(TNF-α、IL-1β、IFN-γ)及细菌脂多糖(lipopolysaccharide，LPS)作用于MCF-10A正常乳腺上皮细胞12 h后，CXCL17的mRNA表达水平改变。蛋白[质]印迹法(Western blot)检测IFN-γ作用于MCF-10A细胞后JAK-STAT通路的活化情况。结果：多种细胞因子及LPS可不同程度地促进CXCL17基因转录，IFN-γ作用最为显著，其通过增加STAT1蛋白的表达水平和磷酸化水平，极大地提高了CXCL17基因转录水平。结论：IFN-γ通过激活JAK-STAT1信号通路使CXCL17在乳腺上皮细胞MCF-10A中表达上调。作为IFN-γ的靶基因，CXCL17很可能是IFN-γ发挥抗炎、抗癌作用的重要环节之一。
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