基于单细胞全外显子组测序的食管鳞状细胞癌放疗抵抗相关克隆进化研究

Esophageal squamous cell carcinoma (ESCC) is a particularly common malignant tumor. ESCC patients always have poor prognosis and high metastasis due to the refractory radioresistance which are closely related with highly heterogeneity of ESCC cells. Single cell exome sequencing (scWES) is becoming riper, and very suitable for the cancer heterogeneity analysis. Here, we have acquired scWES data from one ESCC patient, including normal esophageal tissue (as a control), pre- and pro-radiotherapy cancer tissues. With bioinformatic analysis, we found 2 sub-clones in the pre-radiotherapy samples and 8 radiation-sensitive somatic mutations. Furthermore, we have obtained 153 bulk-cell WES data from radiotherapy-related ESCC samples, which is perfect for the validation of scWES results in larger samples. Based on these works and keep the same sampling method, this project will develop scWES and bioinformatic analysis on the radiotherapy-related samples of 2-3 more ESCC patients in order to validate the acquired scWES results, and to deeply mine the highly heterogeneity and cancer clone evolution, especially ESCC cells evolution during the radiotherapy (radioresistance mechanism of ESCC cells). To sum up, this project based on scWES analyses will provide a new and useful basis for the clinical radiotherapy treatments of ESCC.

食管鳞状细胞癌（ESCC）是常见恶性肿瘤。其易发生放疗抵抗而致预后差和高转移，这与ESCC细胞高度异质性密切相关。单细胞全外显子组测序（scWES）技术可从单个细胞水平分析ESCC细胞群异质性和放疗前后及复发的ESCC克隆进化等。前期研究我们已完成一例ESCC放疗前后样本（含正常对照）scWES，初步分析我们发现在原发癌中存在2个亚克隆和8个放疗敏感基因突变位点。此外我们已经获取153例ESCC放疗样本群体全外显子测序（WES）数据可对单细胞测序结果进行大样本验证。以此为基础，本项目将再获取2-3例ESCC病人放疗前后及复发样本scWES和群体WES数据并进行生物信息学分析。通过相互性验证和补充性分析，最终对ESCC细胞高度异质性及克隆进化，尤其是放疗过程中肿瘤细胞进化机制（即放疗抵抗的形成机制）进行深入挖掘。本项目基于scWES的ESCC克隆进化研究将为ESCC临床放疗提供理论基础。

食管癌是世界第八大癌症，每年有超过48万个新发病例和40万人死亡，其中一半发生在中国，具有非常高的发病率和致死率。其预后差的原因是易发生放化疗抵抗和高转移，这与 ESCC细胞高度异质性密切相关。单细胞全外显子组测序（scWES）和单细胞转录组测序技术可从单个细胞水平分析ESCC细胞群异质性和放疗前后及复发的ESCC克隆进化等。我们对 ESCC 患者组织的 bulk 和单细胞全外显子测序，寻找关键的放射抵抗基因。还对ESCC 与EAC 患者进行单细胞转录组测序，分析肿瘤的异质性。另外对 ESCC 细胞系进行单细胞转录组测序，分析放化疗抵抗相关的关键基因。最后基于测序的结果为对CAR细胞治疗恶性肿瘤包括食管癌在内的前景分析可能有助于未来疗法的设计，改善目标患者的匹配度，并最终帮助我们了解CAR治疗的安全性和有效性。