研究表明肿瘤细胞的“干性”特性的获取和维持，是导致肿瘤持续生长、转移、复发以及耐药等的主要原因之一。在近期工作基础上，我们提出以下科学假说：在口腔鳞癌的发展过程中，髓源抑制细胞（Myeloid-derived suppressor cells, MDSCs）通过推动Lin28介导的细胞不完全重编程作用，促进肿瘤细胞干性。项目拟从以下方面进行研究：①采用磁珠分选、流式细胞术、共培养、免疫荧光等对口腔鳞癌中的MDSCs进行分选、鉴定并分析及其与临床参数相关性；②采用体内、体外实验等分析MDSCs对口腔鳞癌细胞干性特性的影响，及Lin28在其中的作用；③病毒转染、甲基化分析、拟胚体形成、倍比稀释梯度成瘤等分析Lin28介导的不全重编程在MDSCs促进肿瘤细胞干性中的作用机制。项目将深化对MDSCs与口腔鳞癌细胞干性关系认识，为口腔鳞癌的靶向治疗策略提供帮助。

“Stemness” of cancer cell refers to the characteristics that promote cancer development, metastasis, recurrence and drug-resistance. Based on our recent studies, we hypothesize that myeloid-derived suppressor cells (MDSCs) can promote the stemness in oral squamous cell carcinoma (OSCC) by Lin28 mediated partial reprogramming. The project is proposed to study the following aspects: ①The separation and identification of MDSCs in OSCC and its correlation with clinical parameters by using magnetic bead separation, flow cytometry, co-culture and immunofluorescence; ②The influence of MDSCs to the stemness of cells in OSCC and the role of Lin28 in the MDSCs-induced cell stemness in OSCC by using in vivo and in vitro assays; ③The function and mechanism of Lin28-induced partial reprogramming on MDSCs-promoted stemness in OSCC by using virus mediated gene transfer, DNA methylation sequencing, embryonic body formation and limiting dilution assay. The project will deepen our understandings of the relation between MDSCs and cancer cell stemness in OSCC, and provide insights into strategies for targeted treatment in OSCC.