单核细胞分泌白介素-1β与支气管细胞上皮-间质转化的相互调节在肺癌发生中的作用

High content Nano-silica in bituminous coal produced in XuanWwei is its unique characteristics,it has reported that high content of nano-silica in bituminous coal produced in Xuanwei of Yunnan was associated with a high incidence of lung cancer, but the mechanism by which nano-silica contribute to lung tumorigenesis are largely unknow.we have found in previous study that IL-1β secreted by monocyte stimulated by nano-silica can make human bronchial cells undergo an epithelial to mesenchymal transformation, especially ,we first time found that transformed BEAS-2B cells can feedback enhanced secretion of IL-1 β by monocyte. Therefore, we hypothesises that IL-1βreleased by monocyte which stimulated by nano-silica can make human bronchial cells undergo an epithelial to mesenchymal transformation, transformed BEAS-2B cell enhances the secretion of IL-1β by positive feedback, by which IL-1β exert it's role in lung tumoregenesis. In this study, we should employ the co-culture and other methods to explore the molecular regulatory mechanisms interact to regulate the IL-1βsecreting by monocyte and the transformation of human bronchial cells, in order to explore the regulatory effect of IL-1β secreted by monocyte in lung tumoregenesis, and further study the mechanism by which maintain phenotypic transformation to verify our hypothesis. This project not only worthy for study the effect of IL-1β in lung tumorigenesis by providing the theoretical and experimental evidence, it will also contribute to prevente and treat of lung cancer induced by nano-silica by explore the feedback regulation mechanism of IL-1β.

宣威产的烟煤中高含量的纳米二氧化硅是其独有的特点，研究发现烟煤中高含量的纳米二氧化硅与肺癌高发明显相关，但其在肺癌发生中的作用尚未明确。前期研究发现纳米二氧化硅作用下单核细胞分泌的IL-1β能使人支气管细胞发生上皮间质转化，首次发现转化的BEAS-2B细胞能反馈性增强单核细胞分泌IL-1β。因此，我们提出"纳米二氧化硅激活单核细胞释放IL-1β使人支气管细胞发生转化，转化的支气管细胞通过正反馈增强IL-1β分泌，形成的反馈回路引起肺癌发生"的假说。本课题拟采用细胞共培养等方法研究单核细胞分泌IL-1β和支气管细胞转化的相互调节机制，以探索单核细胞分泌IL-1β在肺癌发生中的调节作用，并进一步研究支气管细胞保持转化表型的机制来验证我们的假说。本课题不仅为研究IL-1β在肺癌发生中的作用提供有价值的理论和实验依据，通过IL-1β反馈调节机制研究还有利于为防治纳米二氧化硅所诱导的肺癌提供新的思路

云南宣威是肺癌的高发区，特别是女性肺癌的发生和死亡率为全世界之最。据流行病学调查显示宣威产的烟煤所形成的纳米二氧化硅与宣肺肺癌高发。本研究采用THP-1和BEAS-2B细胞建立共培养体系，采用软琼脂克隆形成实验观察纳米二氧化硅对细胞增殖和EMT的作用，并采用免疫细胞化学检测EMT相关的蛋白水平变化。将克隆细胞接种于裸鼠皮下，观察肿瘤生长的速度，收集瘤体组织检测EMT相关蛋白水平变化，检测细胞凋亡、细胞增殖水平。利用细胞因子芯片筛选在纳米二氧化硅作用下所释放增加的细胞因子，并结合ELISA方法进行确认。为研究在纳米二氧化硅作用下释放增加的细胞因子的功能，我们采用中和抗体作用共培养体系，同样利用软琼脂克隆实验、皮下成瘤的方法观察相应细胞因子中和抗体作用后BEAS-2B细胞EMT水平变化，细胞增殖和凋亡水平的变化，采用磷酸化抗体分析相应细胞因子对应的信号通路是否发生改，结合患者血清中相应细胞因子水平分析其与宣威肺癌发生的关系。研究结果表明纳米二氧化硅可促进BEAS-2B增殖和上皮细胞间质转化，并抑制细胞凋亡，采用细胞因子芯片分析发现在纳米二氧化硅作用下，IL-1β,MCP-3,SDF-1α和TGF-α释放增加，采用中和抗体作用后BEAS-2B细胞增殖能力下降，细胞凋亡水平增高，肿瘤生长速度明显减慢。采集患者血清分析后发现宣威肺癌患者血清中IL-1β,MCP-3,SDF-1α和TGF-α明显高于宣威地区肺良性病变患者，和云南非宣威地区肺腺癌患者，而SDF-1α水平在宣威肺腺癌患者与非宣威肺腺癌患者间并无明显差异。研究表明IL-1β,MCP-3,SDF-1α和TGF-α发挥作用主要是通过NF-κB ，AKT和STAT3信号通路促进BEAS-2B细胞发生恶性转化。本研究表明纳米二氧化硅可促进单核细胞释放IL-1β,MCP-3,SDF-1α和TGF-α，并通过NF-κB ，AKT和STAT3信号通路促进BEAS-2B细胞发生恶性转化，本研究为提示宣威地区环境污染与肺癌高发提供了强有力的理论基础，有利于指导云南宣威肺癌的防治。