肿瘤细胞来源的外泌体lncRNA FAL1调控非小细胞肺癌细胞增殖、自噬的现象及机制研究

Lung cancer has always occupied the primary position in the incidence and mortality of malignant tumors whether in the world or in China. However, and the specific mechanism of tumor growth and progress is still not clear. Recently, the regulation of exosomes and long non-coding RNAs in tumorgenesis and progression has become a hot spot in cancer research. In our previously published study, we found that long non-coding RNA FAL1 promoted the growth, invasion, and metastasis of non-small cell lung cancer (NSCLC) via regulating PTEN by stabilizing BMI1 in vivo and in vitro. With using chip analysis, we found that FAL1 was highly expressed in the exosomes of NSCLC patients. And through preliminary experiments, we confirmed that exosomes secreted by tumor cells could carry FAL1, which is taken up by other surrounding tumor cells, and transport FAL1 into the surrounding cells. We also found that exosomal-FAL1 transported by exosomes promoted the proliferation but inhibited autophagy of NSCLC cells, ultimately leading to tumor growth. Therefore, we next aim to utilize a series of experiment on the clinical, in vitro and in vivo levels, to demonstrate the specific role of exosomal-FAL1 played in the proliferation and autophagy of NSCLC, and to explore the underlying molecular mechanism of exosomal-FAL1. Thereby, this study might provide a new perspective for the study of NSCLC progression, and a potentially viable molecular target for the biological diagnosis, prognosis prediction and targeted therapy for NSCLC.

无论在全世界还是中国，肺癌一直占据恶性肿瘤发病率及致死率中的首位，而其生长进展的具体机制仍不甚清晰。外泌体和长链非编码RNA在肿瘤发生发展中的调控作用成为目前研究的热点。之前已发表的研究中，我们发现长链非编码RNA FAL1可以通过通过稳定BMI1来促进非小细胞肺癌(NSCLC)的生长与转移。我们通过预实验发现FAL1在NSCLC患者外泌体中呈现高表达，且肿瘤细胞分泌的外泌体可以携带FAL1，被周围其他肿瘤细胞摄取后转运至周围细胞内。并且外泌体转运的FAL1可以促进NSCLC细胞的增殖，抑制其自噬，最终促进肿瘤的生长进展。因此，本项目拟深入进行一系列临床、体外及在体水平的研究，阐述exosomal-FAL1对NSCLC增殖及自噬的具体作用，并探索其分子生物学机制，从而为NSCLC生长进展研究提供一个新的角度，也为NSCLC的生物学诊断，预后判断以及靶向治疗提供一个潜在的分子靶标。

近年来，非小细胞肺癌发病率呈持续升高趋势，肿瘤异质性是导致非小细胞肺癌进展的重要因素。外泌体可以介导不同肿瘤细胞间的通讯，传递RNA、蛋白等物质至受体细胞，影响受体细胞的生物学功能，进而参与肿瘤的发生发展过程。我们通过分离提取非小细胞肺癌患者血浆外泌体，鉴定成功后，检测外泌体及肿瘤组织样本中FAL1的表达水平，发现非小细胞肺癌患者血浆中的外泌体FAL1明显高于正常人，并且其表达与患者非小细胞肺癌组织样本中的FAL1表达呈现明显的正相关性。通过构建过表达FAL1的细胞模型，并提取培养鉴定其外泌体后，与受体细胞共培养，证实了FAL1可以通过外泌体被传递到受体细胞中。进而，我们通过一系列的体外功能实验模型证明了，外泌体介导的FAL1转运可以促进受体细胞的增殖，并且抑制其自噬作用，从而促进非小细胞肺癌的进展。机制上，异质性核糖核蛋白A1(hnRNPA1)可以促进肿瘤细胞外泌体FAL1的包装和分泌。外泌体FAL1可以通过稳定靶基因BMI1，进而影响下游的BIM、FBW7等分子的表达，最终影响自噬等信号通路中关键因子。进一步的体内实验也证实了外泌体FAL1可以促进非小细胞肺癌皮下瘤的生长。本项目着重于阐述外泌体lncRNA FAL1在非小细胞肺癌发展的功能和机制，旨在提高非小细胞肺癌诊治的临床效果，改善患者的预后水平，从新的角度寻找非小细胞肺癌的防治新的分子靶标。