Commane Mairead, Jadhav Vidula, Leonova Katerina, Buckley Brian, Withers Henry, Gurova Katerina
Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Elm and Carlton Str, Buffalo, NY, USA, 14263.
Drug Discovery Core Shared Resource, Roswell Park Comprehensive Cancer Center, Elm and Carlton Str, Buffalo, NY, USA, 14263.
bioRxiv. 2024 Sep 6:2024.09.05.611456. doi: 10.1101/2024.09.05.611456.
The phenotypic plasticity of cancer cells has recently emerged as an important factor of treatment failure. The mechanisms of phenotypic plasticity are not fully understood. One of the hypotheses is that the degree of chromatin accessibility defines the easiness of cell transitions between different phenotypes. To test this, a method to compare overall chromatin accessibility between cells in a population or between cell populations is needed. We propose to measure chromatin accessibility by fluorescence signal from nuclei of cells stained with DNA binding fluorescent molecules. This method is based on the observations that small molecules bind nucleosome-free DNA more easily than nucleosomal DNA. Thus, nuclear fluorescence is proportional to the amount of nucleosome-free DNA, serving as a measure of chromatin accessibility. We optimized the method using several DNA intercalators and minor groove binders and known chromatin-modulating agents and demonstrated that chromatin accessibility is increased upon oncogene-induced transformation and further in tumor cells.
癌细胞的表型可塑性最近已成为治疗失败的一个重要因素。表型可塑性的机制尚未完全了解。其中一个假说是染色质可及性的程度决定了细胞在不同表型之间转换的难易程度。为了验证这一点，需要一种方法来比较群体中细胞之间或细胞群体之间的整体染色质可及性。我们建议通过用DNA结合荧光分子染色的细胞核发出的荧光信号来测量染色质可及性。该方法基于以下观察结果：小分子比核小体DNA更容易结合无核小体的DNA。因此，核荧光与无核小体DNA的量成正比，可作为染色质可及性的一种度量。我们使用几种DNA嵌入剂、小沟结合剂和已知的染色质调节剂对该方法进行了优化，并证明在癌基因诱导的转化过程中染色质可及性增加，在肿瘤细胞中进一步增加。
