Zhu Wanyun, Qu Hao, Xu Kaixiang, Jia Baoyu, Li Haifeng, Du Yimin, Liu Guangming, Wei Hong-Jiang, Zhao Hong-Ye
College of Pharmacy and Chemistry, Dali University, Dali, People's Republic of China.
State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, People's Republic of China.
Anim Cells Syst (Seoul). 2017 May 30;21(3):190-198. doi: 10.1080/19768354.2017.1330763. eCollection 2017.
Breast cancer is a heterogeneous disease with distinct subtypes that have made targeted therapy of breast cancer challenging. Previous studies have demonstrated that an altered autophagy capacity can influence the development of breast cancer. However, the molecular differences in starvation-induced autophagic responses in MDA-MB-231 and MCF-7 cells have not been fully elucidated. In this study, we found that an increase of LC3B-II protein expression level and a decrease of the p62 protein expression level in both cells treated by Earle's balanced salt solution. Meanwhile, we observed an increase of autophagosome using transmission electron microscopy and an enhancement in the green fluorescence intensity of LC3B protein by confocal microscopy. Furthermore, we detected the expression of 13 autophagy-related () genes and 11 autophagy signaling pathway-related genes using qPCR. Among 13 genes, we found that 6 genes were up-regulated in treated MDA-MB-231 cells, while 4 genes were up-regulated and 1 gene was down-regulated in treated MCF-7 cells. In addition, among 11 autophagy signaling pathway-related genes, 7 genes were up-regulated in treated MDA-MB-231 cells, while 5 genes were up-regulated and 1 gene was down-regulated in treated MCF-7 cells. These findings suggest that the autophagic response to starvation was different in the two treated cell lines, which will contribute to further study on the molecular mechanism of starvation-induced autophagy and improve the targeted therapy of breast cancer.
乳腺癌是一种具有不同亚型的异质性疾病，这使得乳腺癌的靶向治疗具有挑战性。先前的研究表明，自噬能力的改变会影响乳腺癌的发展。然而，MDA-MB-231和MCF-7细胞中饥饿诱导的自噬反应的分子差异尚未完全阐明。在本研究中，我们发现用Earle平衡盐溶液处理的两种细胞中，LC3B-II蛋白表达水平升高，p62蛋白表达水平降低。同时，我们通过透射电子显微镜观察到自噬体增加，通过共聚焦显微镜观察到LC3B蛋白的绿色荧光强度增强。此外，我们使用qPCR检测了13个自噬相关（）基因和11个自噬信号通路相关基因的表达。在13个基因中，我们发现处理后的MDA-MB-231细胞中有6个基因上调，而处理后的MCF-7细胞中有4个基因上调，1个基因下调。此外，在11个自噬信号通路相关基因中，处理后的MDA-MB-231细胞中有7个基因上调，而处理后的MCF-7细胞中有5个基因上调，1个基因下调。这些发现表明两种处理后的细胞系对饥饿的自噬反应不同，这将有助于进一步研究饥饿诱导自噬的分子机制，并改善乳腺癌的靶向治疗。
