LncRNA-421627增强mTORC1-HIF1-代谢重编程促进结直肠癌转移机制的研究

Colorectal cancer (CRC) metastatic dissemination to the liver and the lung represents the leading cause of CRC-related mortality. But the metastasis mechanism of CRC is still unclear. The category of LncRNAs is very huge, they almost involve in all the processes of the cell life activities. Many researches indicated that LncRNAs have close relationships with the occurrence, progress, invasion and metastasis of CRC, but there is none research on LncRNAs and CRC metabolic reprogramming (Warburg effect) and its molecular mechanism yet. Gene chip scan has been carried out on the specimens of CRC metastasis, and LncRNA-421627 is reminded, which is closely related to the CRC metastasis. The target molecules of LncRNA-421627 are RBM4 and PCBP1 through the predication of catRAPID software and verification of RNA pulldown. Studies have shown that knocked down LncRNA-421627 can lower mTORC1-HIF1-cellular metabolic pathways; subsequent gene chip analysis indicates that LncRNA-421627 likely adjust glycometablism isoenzymes expression to promote CRC cell glycolysis. Therefore, we propose that LncRNA-421627 can enhance mTORC1-HIF1-metabolic reprogramming to promote proliferation and metastasis of CRC. For this purpose, techniques as CRC clone, Tumor-bearing model, genetic intervention, gene expression profile chip, and RNA pulldown, etc. will be adopted in this subject to illuminate the molecular mechanisms that LncRNA-421627 adjusts CRC metabolism and metastasis. This research will help to improve the understanding on LncRNAs regulating tumor metabolic reprogramming, improve the understanding of CRC development and metastasis mechanism , and it could provide a potential target for diagnosis and treatment of CRC.

结直肠癌（CRC）的肝肺转移是患者死亡的主要原因。研究表明LncRNAs与CRC发生、发展和侵袭转移密切相关，但是尚未见LncRNAs与CRC代谢重编程和转移机制的研究。前期我们利用CRC转移标本作基因芯片筛选，获得与CRC转移密切相关的LncRNA-421627。通过catRAPID软件预测和RNA pulldown验证LncRNA-421627可能靶分子是RBM4和PCBP1，后二者可负调mTOC1-HIF1-代谢重编程通路。干扰表达研究提示LncRNA-421627可能通过调节糖代谢同工酶谱转换增强CRC糖酵解。因此提出LncRNA-421627增强mTORC1-HIF1-代谢重编程促进CRC增殖和转移。本课题将利用CRC细胞系、荷瘤模型和基因干预等试图阐明LncRNA-421627调节CRC代谢与转移的分子机制，本研究将有助于完善LncRNAs调节肿瘤代谢重编程和转移机制的认识。

结直肠癌是世界上死亡率第二高的肿瘤，预后较差。近年来多项研究发现长链非编码RNA在结直肠癌的发生过程中发挥着重要作用，但仍有许多与结直肠癌预后相关的lncRNAs仍有待进一步研究。因此本课题旨在挖掘结直肠癌预后相关差异表达lnRNA并探究其潜在的调控作用机制，发现新的结直肠癌预后相关的lncRNA，并探索其参与的潜在调控机制，通过CRC细胞，裸鼠荷瘤模型，基因干预和磷酸化蛋白抗体芯片等研究发现：.（1）数据库挖掘发现四个结直肠癌预后相关lncRNA，分别为FAM222A-AS1、FEZF1-AS1、FAM83H-AS1和LINC00265，均在人类结直肠癌患者中表达上调，并与不良的临床结局密切相关。通过对50对癌旁和肿瘤临床组织进行PCR发现，FAM222A-AS1在CRC组织中表达的确高于癌旁组织，且其高表达与不良预后相关。这表明数据库挖掘所得结直肠癌预后相关lncRNA可以得到临床验证。 .（2）体内体外过表达FAM222A-S1明显促进了CRC细胞的增殖、侵袭以及小鼠荷瘤模型肿瘤的生长。这表明FAM222A-AS1的高表达与结直肠癌的进展密切相关。.（3）RNA荧光原位杂交显示FAM222A-AS1在细胞核和细胞质均有存在，但主要定位于细胞质。这表明FAM222A-AS1主要在细胞质发挥调控作用。.（4）RNA-pulldown实验发现FAM222A-AS1与HIF-1信号通路和糖酵解密切相关。人磷酸化激酶抗体芯片结果显示，p-Akt的降低与FAM222A-AS1的下调相关。这表明FAM222A-AS1可能通过PI3K-Akt-mTOR-HIF-1与癌细胞糖酵解密切相关。.（5）此外，结果显示FAM222A-AS1与miRNA-let-7f具有密切的关系，且miRNA下游靶基因为抑癌基因STAED13，因此FAM222A-AS1也可能通过海绵吸附let-7f从而影响以癌基因STAED13的生物学功能，从而促进结直肠癌的进展。.本研究结果发现CRC相关的新的预后标志物，并揭示lncRNA影响结直肠癌可能的调控方式，为结直肠癌治疗提供新的思路和靶点。