Notch4调控三阴性乳腺癌成瘤转移作用及机制研究

Almost 1.7 million women were diagnosed with breast cancer worldwide each year. Of all breast cancer diagnosed, 15% is triple-negative breast cancer (TNBC) and its overall survival of 13 months has not changed for two decades. The approach to find the master regulators of tumorigenesis and metastasis is the key step to develop the effective therapeutic strategy for TNBC. We found that Notch4 mainly expressed on TNBC cells and regulated its tumorigenesis. Previous research also showed that Notch4 enhanced tumorigenesis and metastasis of TNBC. Based on these results, we speculate that Notch4 is the master regulator to control tumorigenesis and metastasis of TNBC. We first detect the specific expression of Notch4 in the clinical TNBC specimens. Secondly, we measure the influence of ectopic expression of Notch4 on cancer stem cell activity and epithelial-mesenchymal transition at molecular and cellular levels in vitro. Using living mouse imaging technic the influence of ectopic expression of Notch4 on tumorigenesis and metastasis are measured by in situ transplantation assay. Furthermore, we investigate the downstream pathway of Notch4 in TNBC by RNA-seq and mass spectrum technique. TGFβ pathway were found and confrimed to mediate the function of Notch4 in TNBC. The binding of TGFβ1 with Noth4 is further investigated by immunoprecitation assay. Our project that uncover the role of Notch4 in tumorigenesis and metastasis of TNBC and elucidate its molecular mechanism may provide the drug target of therapeutic treatment of TNBC.

全球每年约有170万女性诊断出乳腺癌，其中15%是三阴性乳腺癌，平均生存期13个月且最近20年没有发展有效的治疗策略。找到关键的成瘤和转移驱动因子，是当前三阴性乳腺癌药物研发的核心策略。我们前期研究发现Notch4主要在三阴性乳腺癌中表达，干扰Notch4后抑制三阴型乳腺癌增殖。国内外研究也显示Notch4可能促进乳腺癌癌症干细胞活性和上皮间充质转换。我们推测“Notch4可能是促进三阴性乳腺癌成瘤和转移的驱动因子”。本项目以此为基础，以Notch4调控三阴性乳腺癌成瘤和转移为主线，以癌症干细胞和上皮间充质转换为切入点，夯实Notch4在调控三阴性乳腺癌成瘤和转移的核心作用，深入研究其调控成瘤和转移的分子机制，期望在发现三阴性乳腺癌成瘤和转移的驱动因子，认识其生物学功能及机制取得突破，并为三阴性乳腺癌新药创制和临床治疗新策略提供实验依据。

我们发现三阴性乳腺癌细胞沉默Notch4后抑制乳腺癌上皮间充质转换和增强成瘤能力。三阴性乳腺癌沉默Notch4成瘤能力增强，机制促进多潜能干细胞转录因子Nanog表达增加有关。三阴性乳腺癌细胞沉默Notch4降低转移能力，机制与沉默Notch4降低极性形成因子CDC42表达，导致与其结合的Vimentin分散在细胞核周围有关。因此，Notch4不能作为三阴性乳腺癌的药物研发靶标。论文投稿在cell disease and death（见附件2，影响因子/分区 9.685/Q1，评审阶段）. 编号CDDIS-22-5098。该课题还支撑了5篇已经发表论文发表见研究成果。1）Patient-derived primary breast cancer cells and their potential for predicting sensitivity to chemotherapy. （通讯作者）IF: 5.738/Q2 该研究突破了乳腺癌原代细胞培养瓶颈问题，可以高效率77%分离乳腺癌原代细胞，并且建立乳腺癌细胞系。该技术可能为乳腺癌药物敏感实验，研究乳腺癌成瘤和转移机制提供新的手段。2）The neural stem cell properties of Pkd2l1+ cerebrospinal fluid-contacting neurons in vivo.（共同通讯）IF: 6.147/Q2 该研究首次体内证明触液神经元是神经干细胞，为脊髓损伤修复提供新的干细胞来源。3）Notch3调控Hes2逆转三阴性乳腺癌上皮-间质转化的机制研究。（通讯作者）4）Mutational analysis of compound heterozygous mutation p.Q6X/p.H232R in SRD5A2 causing 46,XY disorder of sex development.（共同通讯）IF: 3.288/Q4该研究阐明一个家族性发育紊乱的机制，为该家族生育健康儿童和婚姻配偶选择提供了机制。5）Wnt7a promotes the osteogenic differentiation of human mesenchymal stem cells.（共同通讯）IF: 4.101/Q2证实Wnt7a在骨形成中扮演重要角色。.