Single cell sequencing identifies novel sub-populations of breast cancer cells selected under hypoxia

During tumour growth cancer cells are subject to and selected by microenvironmental stress. The selection of such cells allows for continued growth and survival, during hypoxia, acidosis, nutritional deprivation, drug treatment and radiation. However, there is great microenvironmental heterogeneity in every tumour. Must studies of gene regulation in vitro investigate whole cell populations, often by western blotting or mRNA expression. Thus, the individual variability of gene induction that could lead to selection, and basal cell molecular variability on which the selection operates, basic Darwinian principles, are not defined. We previously showed that two distinct populations can often be induced in epithelial tumour cell lines under hypoxia, identified by induction of Carbonic Anhydrase 9 [CA9].Here, we investigated the heterogeneity of breast cancer cells, and the relationship to the CA9 positive population in hypoxia, by using single cell sequencing analysis. Overall design: Examination of the MCF7 breast cancer cell line using single cell transcriptomics (smartseq2)

肿瘤生长过程中，癌细胞会受到微环境应激的作用并被其筛选。此类细胞的筛选使其可在缺氧、酸中毒、营养剥夺、药物处理及放射辐照等条件下持续增殖与存活。然而，所有肿瘤内部均存在显著的微环境异质性。目前，体外基因调控相关研究大多以整体细胞群体为研究对象，常采用蛋白质印迹法（western blotting）或mRNA表达检测技术。因此，可引发筛选的基因诱导个体差异，以及筛选所依托的基础细胞分子变异（即基础达尔文进化论原理），均尚未得到明确阐释。我们此前的研究表明，缺氧条件下上皮肿瘤细胞系中通常可诱导出两种不同的细胞群体，可通过碳酸酐酶9（Carbonic Anhydrase 9, CA9）的诱导表达进行鉴定。本研究通过单细胞测序分析，探究了乳腺癌细胞的异质性及其与缺氧环境下CA9阳性细胞群体的关联。实验整体设计：采用单细胞转录组学（smartseq2）技术对MCF7乳腺癌细胞系进行检测分析。