碘干预剪接因子MATR3调控lncRNA MALINC1的可变剪接靶向Pura基因在甲状腺乳头状癌中的作用机制

碘过量或缺乏均与甲状腺乳头状癌（PTC）相关，机制复杂未明，寻找PTC患者适宜的碘浓度、揭示其机制意义重大。我们前期发现PTC患者尿碘值与瘤体大小、周围浸润、癌组织自噬和凋亡相关，10-6mol/L碘使PTC细胞发生基础自噬，促进细胞增殖、迁移等。为明确碘与PTC的关系及分子机制，本项目继续完善PTC患者尿碘值与肿瘤特征的关系，包括淋巴结转移、其他超声信号和癌组织Ki67等；利用PTC细胞RNA-seq测序结果结合人类基因组注释文件，基于生物信息学方法获得候选剪接因子、lncRNA及其靶基因，在细胞水平研究碘干预剪接因子对lncRNA可变剪接的调控，minigene、CLIP等检测剪接异构体并观察细胞生物学行为探讨靶基因的功能；研究不同碘水平时动物模型从肿瘤表型到相关分子的异常，并分析PTC患者尿碘值与癌组织中相关分子的关系，揭示碘对PTC的影响及机制，为指导PTC患者合理碘摄入提供依据。

Iodine excess and iodine deficiency are both associated with papillary thyroid cancer(PTC), however, the underlying mechanism is still unclear. It is of great significance to determine the optimal iodine nutrition level of PTC patients, and reveal the mechanism. Our previous study demonstrated that urinary iodine concentrations of PTC patients were associated with the mean tumour size, the invasion ability, and apoptosis and autophapy of the malignant tissues. The activity of proliferation and migration rates of PTC cells increased, and the autophagy level remained unchanged at 10-6mol/L iodine concentrations. On this basis, in order to figure out the relationship between iodine and the PTC and the molecular mechanism, our project will continue to focus on the relationship between urinary iodine concentrations of PTC patients and the characteristics of cancer, including lymph node metastasis, other signal assessed by ultrasound, Ki67 levels of the tissue and so on. Furthermore, candidate splicing factors, lncRNAs, and target genes were screened, based on RNA-seq sequencing technology and bioinformatics method. PTC cells will be involved to study the effect of iodine on alternative lncRNAs by regulating splicing factors. LncRNA isoforms will be detected by minigenes assay and CLIP methods. Biological behaviors and the function of target genes will also be illustrated in cell experiments. Two mouse xenograft models will be constructed to observe the tumor phenotype and aberrant moleculars at different iodine concentrations, and the related moleculars will then be verified to its correlation with urinary iodine concentrations of PTC patients. Thus, the mechanism of iodine affecting PTC tumor will be revealed, so as to provide a basis for the reasonable iodine intake of PTC patients.