长链非编码RNA下调ErbB2表达抑制肝癌射频消融后残癌细胞Warburg效应的机制研究

The proliferation and metastasis of the residual tumors (RTs) is an important cause to limit the therapeutic effect of radiofrequency ablation (RFA) in the treatment of liver cancers. Warburg Effect is closely related to the proliferation, invasion and metastasis of tumor cells. Our preliminary experiments found that: the Warburg effect of the RTs was inhibited at early stage after RFA, but the exact mechanism is unclear. erb-b2 receptor tyrosine kinase 2 is an important molecule in the regulation of Warburg effect. Long noncoding RNA（lncRNA）can regulate the proliferation of tumor cells by way of Warburg effect. Our previous research found that: lncRNA ENST00000570843.1 is highly expressed in the residual cancer cells. However, ErbB2 was significantly up-regulated after interfering with the expression of lncRNA ENST00000570843.1. Additionally, we Predicted that the promoter region of ErbB2 can bind the transcription factor Nkx2-5, which have a negative regulation effect. So, lncRNA ENST00000570843.1 may inhibit the Warburg effect of RTs by way of inhibiting expression of ErbB2 after binding Nkx2-5. This study may provide new molecular targets which can block the proliferation of RTs after RFA and has important clinical significance.

残余肿瘤细胞（残癌）的增殖、转移是限制射频消融（RFA）治疗肝癌手术疗效的重要原因。Warburg效应与多种肿瘤细胞的增殖和侵袭转移密切相关。我们预实验显示RFA术后早期残癌细胞Warburg效应受抑制，但具体机制不清。erb-b2受体酪氨酸激酶2（ErbB2）是调控肿瘤细胞Warburg效应的重要分子。长链非编码RNA（lncRNA）可以通过调控Warburg效应从而调控肿瘤细胞的增殖。我们前期研究发现lncRNA ENST00000570843.1在残癌细胞中高表达，干扰其表达后ErbB2表达显著上调。且预测转录因子Nkx2-5与ErbB2启动子区域有结合位点，具有负性调控作用。因此，lncRNA ENST00000570843.1可能通过结合Nkx2-5抑制ErbB2表达，从而抑制残癌细胞的Warburg效应。该课题为阻断RFA术后残癌增殖提供新的分子靶点，具有重要的临床意义。

研究背景：残余肿瘤细胞增殖、转移是限制射频消融（RFA）治疗肝癌手术疗效的重要原因。Warburg效应与肿瘤细胞的增殖和侵袭转移密切相关。我们推测肝癌RFA治疗后残癌细胞早期在亚致死性热应激刺激下，高表达lncRNA ENST00000570843.1 (简称lncENST)，lncRNA通过结合转录因子Nkx2-5，激活Nkx2-5的活性，抑制ErbB2基因转录，进而下调ErbB2蛋白表达，抑制Akt和Ras信号通路，达到抑制残癌细胞Warburg效应的作用。研究内容：1）lncENST在抑制RFA后残癌细胞 Warburg效应中的作用：通过不同细胞及动物模型，研究了lncENST表达改变与RFA后残癌细胞 Warburg 效应改变的关系，明确了lncENST可通过促进肝癌细胞凋亡抑制Warburg效应；2）通过不同模型，研究了ErbB2表达与抑制RFA后残癌细胞 Warburg 效应的关系，明确了ErbB2 蛋白对Warburg 效应的影响。3）通过研究lncENST表达与ErbB2表达的相互关系，明确了lncENST可下调 ErbB2蛋白表达，进而抑制RFA后残癌细胞 Warburg效应。4）研究Nkx2-5在lncENST下调ErbB2蛋白表达中的作用，及Nkx2-5的活化在ErbB2表达降低中的作用及机制，明确了lncENST在抑制Warburg效应中的作用及机制。结果：1）亚致死性热温度刺激可增强LncENST对HCC肿瘤的抑制作用；2）lncENST过表达可抑制Warburg效应及肿瘤生长,RFA具有协同增强作用；3)ErbB2可促进Warburg效应，Nkx2-5具有拮抗作用；4）lncENST可抑制ErbB2转录表达；5）lncENST抑制ErbB2是通过激活Nkx2-5途径实现；6）Nkx2-5通过转录调控抑制肝癌移植组织中ErbB2的表达。科学意义：本课题研究肝癌RFA术后残癌细胞增殖转移的机制，为提高手术疗效提供新的靶点，具有重要的临床意义，也为后续研究打下了坚实的基础。