Background/Objectives: Smokers are at an increased risk of developing mucosal head and neck squamous cell cancers (HNSCCs) and have a worse prognosis when treated. The cellular and molecular mechanisms underlying the latter has not been established. We therefore developed an in vitro model to investigate the effects of radiation and smoking on mucosal HNSCCs. FaDu hypopharyngeal cancer cells were subjected to daily fractionated radiation and cultured with and without cigarette-smoke-exposed media.Methods: The cells were characterised using assays for tumour sphere formation, proliferation, migration, invasion, CD44 and ALDH expression, and next generation sequencing. We also evaluated CD44 and ALDH1 expression in patient tumour samples.Results: Radiation and smoking separately reduced FaDu tumour sphere/Cancer Stem Cell (CSC) number and proliferation, and increased cell migration and invasion. Combined, they further reduced CSC number proliferation and promoted migration. CD44 and ALDH co-expression was reduced in conditions with cigarette smoke. Through next generation sequencing, radiation and smoking produced a gene signature related to cell invasion, angiogenesis, and survival. Immunohistochemistry for CD44 and ALDH1 on patient tumour specimens did not demonstrate a relationship with smoking status, supported our in vitro findings.Conclusions: The data show the utility of a new experimental model to test the combination of radiation and smoking on mucosal HNSCCs behaviour.
背景/目的：吸烟者罹患黏膜头颈部鳞状细胞癌（HNSCCs）的风险增加，且接受治疗后预后更差。其背后的细胞与分子机制尚未明确。为此，我们开发了一种体外模型，以研究辐射与吸烟对黏膜HNSCCs的影响。我们将下咽癌FaDu细胞进行每日分割照射，并分别在含或不含香烟烟雾暴露培养基的条件下培养。 方法：通过肿瘤球形成、增殖、迁移、侵袭、CD44与ALDH表达检测及新一代测序技术对细胞进行表征分析。同时评估了患者肿瘤样本中CD44与ALDH1的表达情况。 结果：辐射与吸烟分别降低了FaDu肿瘤球/癌症干细胞（CSC）数量及增殖能力，并增强了细胞迁移与侵袭能力。二者联合作用进一步减少了CSC数量与增殖，同时促进细胞迁移。在香烟烟雾暴露条件下，CD44与ALDH共表达水平降低。新一代测序显示，辐射与吸烟共同作用产生了与细胞侵袭、血管生成及生存相关的基因特征谱。对患者肿瘤标本进行的CD44与ALDH1免疫组化分析未显示其表达与吸烟状态存在关联，这支持了我们的体外研究结果。 结论：本研究数据证实了该新型实验模型可用于测试辐射与吸烟联合作用对黏膜HNSCCs生物学行为的影响。
A New Model to Investigate the Action of Radiation and Cigarette Smoke on Head and Neck Cancer Cells
肿瘤(癌症)患者之家