Syt14促进肺腺癌的发生、发展及其分子机制

Synaptotagmin (Syt) is mainly expressed in vesicle membrane and regulates vesicle activation, transport and fusion, playing a critical role in the pathogenesis of many diseases such as neurological, endocrine and malignant diseases. We firstly discovered that Syt14 was significantly upregulated in lung adenocarcinoma compared with the surrounding normal tissue by analyzing the data from The Cancer Genome Atlas (TCGA) and further confirming with the immunohistochemistry and qRT-PCR assays. Furthermore, we confirmed that Syt14 significantly promoted the proliferation, migartion and invasion while inhibited the apoptosis of lung adenocarcinoma cells in vitro, suggesting that Syt14 might facilitate the tumor genesis and development of lung adenocarcinoma. Thus, further investigation is to figure out the clinical relationship of Syt14 with lung adenocarcinoma by using larger sample volumes. Subsequently, CRISPR/Cas9 assays will be performed to examine the impact of Syt14 on tumor genesis, growth and metastasis in the mouse model of lung adenocarcinoma. Then, we are trying to identify the signaling pathways and interaction molecules of Syt14 in lung adenocarcinoma by means of immunoprecipitation (IP) and next generation sequencing (NGS) assays. The project aims to further elucidate the promotion of tumor genesis and development of lung adenocarcinoma by synaptotagmin14 and the underlying molecular signaling pathways, which will contribute to the understanding of the molecular mechanism of lung cancer and providing a potential therapeutic target for lung adenocarcinoma.

突触结合蛋白（synaptotagmin，Syt）主要分布于囊泡膜，参与调节囊泡的激活、转运和融合，在神经、内分泌疾病及恶性肿瘤的发病机制中扮演重要角色。通过TCGA数据分析、qRT-PCR及免疫组化实验，我们发现Syt14在肺腺癌中的表达显著高于癌旁组织；采用RNAi等技术证实Syt14促进肺腺癌细胞的增殖、转移和侵袭，但抑制其凋亡。由此推测，Syt14可能促进肺腺癌的发生、发展过程。故本项目拟：扩大样本量，进一步分析Syt14与肺腺癌的临床相关性；以小鼠肺腺癌模型为研究对象，采用CRISPR/Cas9等技术，探讨Syt14对肿瘤发生、生长和转移的影响；采用二代测序、免疫共沉淀等技术，鉴定肺腺癌中Syt14的信号通路和互作分子。本研究旨在进一步明确Syt14对肺腺癌发生、发展的促进作用及其分子调控通路，以期为阐明肺癌发生的分子机制提供新的实验数据，亦有望为肺腺癌治疗提供潜在的药物靶点。

癌基因的激活/抑癌基因的失活是癌症发生的根本原因，积极探索肺癌发生、发展中的分子事件无疑具有重大的科学意义和潜在的应用价值。突触结合蛋白(SYT)是一种横跨囊泡膜的穿膜蛋白，在囊泡的激活、转运及融合等过程中发挥重要的调控作用，进而参与恶性肿瘤的病理生理过程。本研究深入探讨了SYT14在肺腺癌发生、发展中的作用及其分子机制，结果发现：1）SYT14在肺腺癌中的表达显著高于癌旁正常组织；2）SYT14可促进肺腺癌细胞的增殖、侵袭、上皮细胞-间充质转化(EMT)及外泌体合成/分泌等生物学行为；3）SYT14可促进KRAS野生型人肺腺癌类器官的生长和增殖；4）SYT14可显著影响肺腺癌中细胞周期相关调控分子的表达；5）KRAS突变可明显抑制肺腺癌中SYT14的表达。综上研究提示：1）SYT14可通过调控细胞周期而促进肺腺癌的发生、发展过程；2）肺腺癌中KRAS突变状态是影响SYT14表达的重要遗传因素。.基于本项目的研究资源，我们积极探讨了非小细胞肺癌(NSCLC)发生、发展中的其他分子事件，结果发现：1）肺腺癌中神经纤维蛋白-1(NF-1)功能缺失可引起局灶性粘附激酶-1(Fak-1)的过度活化和磷酸丝氨酸氨基转移酶-1(Psat-1)的过度表达，进而促进疾病的进展，Psat-1抑制剂对NF-1/KRAS共突变型肺腺癌具有潜在的治疗作用；2）miR-193a-3p可通过抑制p21激活激酶-4(PAK-4)活性，降低Slug磷酸化水平，下调L1细胞粘附分子(L1CAM)的表达，进而抑制NSCLC的侵袭；3）淀粉样前体蛋白结合蛋白-2(APPBP-2)通过PPM1D和SPOP的介导而促进NSCLC细胞的增殖和侵袭；4）circRNA circP4H通过吸附miR-133a-5p而促进NSCLC的侵袭和转移；5）毛壳菌素，HSP90/HIF-1α通路抑制剂，可抑制NSCLC干细胞和非干性细胞的增殖；6）高压氧治疗通过调控HIF-1a/PFKP通路而抑制乏氧状态下NSCLC细胞的增殖、EMT及Warburg效应。.本项目的系列研究，进一步揭示了NSCLC(尤其是肺腺癌)发生、发展中的分子事件，为进一步阐明NSCLC发生的分子机制提供了新的实验数据，亦为NSCLC的精准诊疗提供了新的策略。