【摘要】 镍化合物广泛存在于人类职业环境中,是人类发生肺癌的主要危险因素。我们前期研究已证实金属毒物结晶型硫化镍(NiS)的暴露是发生肺癌的重要病因,但具体的致癌机制仍未明了。本研究利用前期建立的结晶型 NiS 恶性转化人支气管上皮细胞的细胞模型,首次采用激光共聚焦扫描显微镜成像技术,在无损伤状态下,实时观测恶性转化细胞(16HBE-T)和正常细胞(16HBE-N)中自噬体标记蛋白 GFP-LC3 的荧光强度及定位,并利用 Western Blotting 技术检测细胞内自噬信号通路关键效应分子的表达。共聚焦实验结果表明:16HBE-T 细胞与 16HBE-N 细胞相比,GFP-LC3 蛋白的点状聚集明显减少,经测量只有 16HBE-N 细胞的 1/3 左右,表明自噬水平下降;Western Blotting 检测发现:mTOR 激酶活性上升,Beclin 1 表达下降。上述结果证明,结晶型 NiS可通过多个自噬途径参与诱导 16HBE 细胞恶性转化的癌变过程,将为预防和治疗肺癌提供重要信息。更多还原

【Abstract】 Nickel com pounds, which widely exist in the environment of human occupation, are the major risk factor for human lung cancer. Our previous studies had confirmed that exposure to toxic,metallic crystalline nickel sulfide (NiS) was an important cause of lung cancer, but the concrete carcinogenic mechanism is still unclear. In this study, we used the previouslyestablished human bronchial epithelial (16HBE-T) cells malignant transformation model, which was induced by crystalline NiS. For the first time, fluorescence intensity and position of the GFP-LC3 protein in malignant transformed (16HBE-T) cells and normal cell (16HBE-N), were real-time monitored with the technique of confocal laser scanning microscopy imaging without damaging the condition. Moreover, we used Western Blotting to detect the intracellular autophagic signal which is expressed by key effective molecule pathway. Confocal experimental results showed that: Compared with that of 16HBE-N-cells, the GFP-LC3 protein punctate aggregation of 16HBE-T cells significantly reduced to the merely 1/3 amount of 16HBE-N-cells, suggesting that autophagy levels declined. At the same time, it was found that the mTOR kinase activity increased, and that Beclin 1 expression decreased. The above research result demonstrated that the mechanism of crystalline NiS induced 16HBE cell malignant transformation was through multiple autophagic pathway and it will provide an important message in the prevention and treatment of lung cancer.更多还原