Department of Nutrition and Food Safety, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, China.
Suzhou Digestive Diseases and Nutrition Research Center, North District of Suzhou Municipal Hospital. The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, 215008, China.
Theranostics. 2019 Jul 9;9(16):4827-4840. doi: 10.7150/thno.33812. eCollection 2019.
Tobacco smoke (TS) critically contributes to the development of lung cancer; however, the underlying molecular mechanisms remain unclear. The induction of cancer stem cells (CSCs) by TS represents an early event in tumor initiation. The lung cancer-related gene ΔNp63α is highly expressed in epithelial tissues and drives tumor formation and cancer stem cell properties. This study investigated the role of ΔNp63α in the long-term acquisition of TS-induced lung CSC-like properties. The expression levels of ΔNp63α, lung CSC markers, and interleukin (IL)-6 in lung carcinoma specimens were determined by western blotting and enzyme linked immunosorbent assays. Human bronchial epithelial (HBE) cells were chronically exposed to 2 % cigarette smoke extract for 55 passages, following which colony formation capacity, expression of proteins associated with malignant transformation, lung CSC markers, and tumor incidence were investigated. The effects of ΔNp63α on long-term TS exposure-induced lung CSC-like properties and Notch activation were analyzed using tumorsphere formation ability, immunofluorescence assays, luciferase reporter assays, and western blotting. The roles of IL-6 on chronic TS exposure-induced lung CSC-like properties and ΔNp63α expression were also examined. Moreover, the effects of sulforaphane (SFN) on TS-transformed lung CSC-like properties, IL-6 and ΔNp63α expression, and Notch signaling were investigated and . Higher levels of ΔNp63α were observed in the lung cancer tissues of smokers than in those of non-smokers, whereas ΔNp63α was positively correlated with CD133 and Oct4 expression in lung cancer tissues. Data from the and experiments demonstrated that long-term TS exposure-transformed HBE (THBE) cells acquired lung CSC-like properties. Furthermore, ΔNp63α transcriptionally activated the Notch signaling pathway to promote the acquisition of CSC-like properties by the THBE cells. TS upregulated IL-6, which increased ΔNp63α expression in THBE sphere-forming cells. Finally, SFN inhibited the TS-induced CSC-like properties of THBE cells the IL-6/ΔNp63α/Notch axis. : Our data suggest that the IL-6/ΔNp63α/Notch axis plays an important role in the long-term TS exposure-induced acquisition of lung CSC-like properties and SFN intervention.
烟草烟雾（TS）是肺癌发展的关键因素，但其中的分子机制尚不清楚。TS 诱导癌症干细胞（CSC）的产生是肿瘤起始的早期事件。与肺癌相关的基因ΔNp63α在上皮组织中高度表达，并驱动肿瘤形成和癌症干细胞特性。本研究探讨了ΔNp63α在 TS 诱导的肺 CSC 样特性的长期获得中的作用。通过 Western blot 和酶联免疫吸附试验测定肺癌标本中ΔNp63α、肺 CSC 标志物和白细胞介素（IL）-6 的表达水平。用 2%香烟烟雾提取物对人支气管上皮（HBE）细胞进行慢性暴露，共 55 代，然后研究集落形成能力、与恶性转化相关的蛋白表达、肺 CSC 标志物和肿瘤发生率。使用肿瘤球形成能力、免疫荧光分析、荧光素酶报告基因分析和 Western blot 分析ΔNp63α对长期 TS 暴露诱导的肺 CSC 样特性和 Notch 激活的影响。还研究了 IL-6 对慢性 TS 暴露诱导的肺 CSC 样特性和ΔNp63α表达的作用。此外，还研究了萝卜硫素（SFN）对 TS 转化的肺 CSC 样特性、IL-6 和ΔNp63α表达以及 Notch 信号的影响。结果吸烟者肺癌组织中ΔNp63α水平高于不吸烟者，而肺癌组织中ΔNp63α与 CD133 和 Oct4 表达呈正相关。和实验数据表明，长期 TS 暴露转化的 HBE（THBE）细胞获得了肺 CSC 样特性。此外，ΔNp63α转录激活 Notch 信号通路，促进 THBE 细胞获得 CSC 样特性。TS 上调 IL-6，增加 THBE 球形成细胞中ΔNp63α的表达。最后，SFN 抑制了 TS 诱导的 THBE 细胞的 CSC 样特性，抑制了 IL-6/ΔNp63α/Notch 轴。结论：我们的数据表明，IL-6/ΔNp63α/Notch 轴在长期 TS 暴露诱导的肺 CSC 样特性获得中起重要作用，SFN 干预可能具有重要意义。
