LKB1-AMPK激酶通过调控Hippo信号通路参与维持乳腺上皮细胞染色质稳定性的机制研究

Chromosome instability is a characteristic of most cancers and one of the major changes in malignant transformation of epithelial cells. Hippo signaling pathway has been found to play an important role in maintaining cell chromosome stability. Previous reports have confirmed that LKB1-AMPK kinase pathway is closely related to carcinogenesis and progression of breast cancer. However, the detailed mechanism underlying the role of LKB1-AMPK kinase pathway in maintaining chromosome stability of breast cancer cells has not been elucidated. In our preliminary experiment, we found that loss of LKB1 in human breast cancer cells up-regulated the expression of Hlgl 1/2 protein but down-regulated the expression of AMOT80 protein. Moreover, both Hlgl 1/2 and AMOT80 proteins are important members in Hippo signaling pathway. Therefore, we hypothesize that dysfunction of LKB1-AMPK kinase pathway may cause chromosome instability in breast cancer cells through regulating the activity of Hippo pathway. In this project, we intend to research on the mechanism underlying the role of LKB1-AMPK kinase pathway in maintaining chromosome stability of breast cancer cells by selecting human MCF10A mammary epithelial cell line and breast cancer cell line as the research object and using molecular cell biology approaches. This project is expected to reveal the detailed mechanism underlying the role of LKB1-AMPK kinase pathway in maintaining chromosome stability of mammary epithelial cells through regulating Hippo signaling pathway.

染色质不稳定是细胞恶性转化过程中的重要改变和恶性肿瘤的重要特征，Hippo通路是维持细胞染色质稳定性的重要通路。研究证实LKB1-AMPK激酶通路与乳腺癌发生、发展密切相关。然而，目前对LKB1-AMPK激酶通路维持乳腺上皮细胞染色质稳定性的细节机制尚未阐明。我们前期研究发现，LKB1缺失的乳腺癌细胞，Hippo 通路的AMOT80 蛋白表达上调，而Hlgl 1/2蛋白表达显著上调。因此，我们设想：LKB1-AMPK激酶异常可引起Hippo通路的活性发生改变，进而导致乳腺癌细胞染色质不稳定以及细胞恶性表征的改变。我们拟以人乳腺上皮细胞MCF10A以及不同乳腺癌细胞系为研究对象，利用细胞分子生物学研究手段，对LKB1及AMPK缺失或失活后的乳腺癌细胞染色质稳定性进行系统研究，该项目的完成，将阐明LKB1-AMPK激酶通过调控Hippo信号通路参与维持乳腺上皮细胞染色质稳定过程中的细节机制。

LKB1-AMPK激酶通路参与维持乳腺上皮细胞染色质稳定性。本研究中，我们通过Western Blot免疫蛋白印记技术、染色体核型分析等分子生物学技术，我们对LKB1-AMPK激酶通路维持乳腺上皮细胞染色质稳定性的分子生物学机制进行初步研究。首先我们发现，乳腺上皮细胞或乳腺癌细胞LKB1、AMPK激酶缺失或失活时可导致染色质不稳定，但在探讨LKB1是否通过调控Hippo-Yap 通路参与维持染色质稳定性时发现，LKB1维持染⾊质稳定的机制可能与细胞极性有关联，探讨LKB1是否通过调控Hippo-Yap 通路参与维持染色质稳定性时发现，LKB1维持染⾊质稳定的机制可能与细胞极性有关联，通过研究我们发现 DLG5可以通过改变Scribble的表达与定位来调节 Hippo 信号通路，可能在LKB1维持染⾊质稳定的机制中起到重要作用，后续实验正在进行。综合上述结果，本研究为探讨LKB1-AMPK激酶通路参与维持乳腺上皮细胞染色质稳定性奠定了坚实的工作基础，同时为乳腺癌发病机制提供重要线索。项目资助发表SCI论文2篇，核心期刊论文1篇，待发论文1篇，培养博士生1名，硕士生1名，其中博士生已获得博士学位，硕士生在读。项目投入16万元，各项支出基本与预算相符。