LncRNA RP3-340B19.3作为乳腺癌诊断与预后分子标志物及其作用机制研究

LncRNAs play an important role in the development and progression of breast cancer and have the potential to be utilized as the biomarker for the diagnosis of breast cancer. In our previous study, we found that TLR4-activated breast cancer cells had increased metastatic potential. The results of microarray showed that RP3-340B19.3 was highly expressed in TLR4-activated breast cancer cells. The knockdown of RP3-340B19.3 significantly inhibited the migration of breast cancer cells. The results of bioinformatics analysis showed that the expression of RP3-340B19.3 was positively correlated with that of NFKBIZ, indicating that RP3-340B19.3 may up-regulate NFKBIZ expression and activate IκBζ/NF-κB signaling pathway to promote breast cancer metastasis. In addition, RP3-340B19.3 was highly expressed in the tumor tissues, serum and serum exosome of breast cancer patients, suggesting that RP3-340B19.3 may serve as a novel marker for breast cancer diagnosis. Therefore, we attempt to use cell and molecular biology techniques as well as animal models to investigate the role and mechanism of RP3-340B19.3 in breast cancer metastasis and to clarify its application value in the diagnosis and prognosis of breast cancer. The findings of our proposed study will provide new indicators for the diagnosis and treatment of breast cancer.

LncRNAs在乳腺癌发生发展中具有重要作用，有望成为乳腺癌诊断分子标志物。我们前期研究发现TLR4活化的乳腺癌细胞转移能力增强，芯片筛选发现TLR4活化的乳腺癌细胞显著高表达RP3-340B19.3，生物学验证表明RP3-340B19.3基因敲减降低乳腺癌细胞迁移能力。生物信息学分析显示RP3-340B19.3与NF-κB信号通路调节基因NFKBIZ表达呈正相关，提示RP3-340B19.3可能通过调控NFKBIZ表达激活IκBζ/NF-κB信号通路促进乳腺癌转移。临床检测发现乳腺癌患者RP3-340B19.3表达较健康人显著升高，提示RP3-340B19.3可能是乳腺癌诊断的新指标。因此，本研究拟采用细胞、分子生物学技术以及动物实验研究RP3-340B19.3在乳腺癌转移中的作用及机制，同时结合临床资料分析其在乳腺癌诊断和预后判断中的应用价值，从而为乳腺癌诊治提供新的思路和靶标。

非编码RNA在乳腺癌发生发展中具有重要作用，是乳腺癌诊断分子标志物。本研究主要探讨TLR4活化后的LncRNA分子RP3-340B19.3和miRNA分子miR-1910-3p和miR-370-3p在乳腺癌转移中的作用、分子机制及临床应用价值。研究发现，TLR4活化后，乳腺癌细胞显著高表达RP3-340B19.3、 miR-1910-3p及miR-370-3p。成功构建高低表达RP3-340B19.3、miR-1910-3p和miR-370-3p的乳腺癌细胞株。RP3-340B19.3、miR-1910-3p及miR-370-3p体内外能够促进乳腺癌细胞的增殖、迁移及EMT。机制方面，RP3-340B19.3可通过直接结合miR-4510活化NF-κB及Wnt信号通路促进乳腺癌增殖和转移。外泌体通过传递miR-1910-3p靶向抑制MTMR3的表达活化NF-κB信号通路促进乳腺癌细胞生长、转移及自噬。miR-370-3p的种子序列和FBLN5mRNA 3’-UTR结合活化NF-κB信号通路促进乳腺癌的增殖及转移。乳腺癌患者血清来源exosome内RP3-340B19.3、miR-1910-3p及miR-370-3p具有较好的诊断效能。RP3-340B19.3、miR-1910-3p及miR-370-3p表达水平与临床病理资料中的肿瘤直径、病理类型、淋巴结转移及TNM分期显著相关。综上所述，RP3-340B19.3、miR-1910-3p及miR-370-3p是参与乳腺癌转移的关键分子。血清外泌体源性RP3-340B19.3、miR-1910-3p及miR-370-3p可能是乳腺癌诊断的潜在新型分子标志物，具有重要的临床应用价值。