Proteros Biostructures GmbH, Bunsenstraße 7a, 82152, Planegg, Germany.
Discovery Sciences, Janssen Research and Development, 1400 McKean Road, Spring House, Pennsylvania 19477, United States.
SLAS Discov. 2022 Jul;27(5):306-313. doi: 10.1016/j.slasd.2022.04.003. Epub 2022 May 2.
The dysregulation of the PRC1/2 complex plays a key role in lineage plasticity in prostate cancer and may be required to maintain neuroendocrine phenotype. [1] CBX2, a key component of the canonical PRC1 complex, is an epigenetic reader, recognizing trimethylated lysine on histone 3 (H3K27me3) [2] and is overexpressed in metastatic neuroendocrine prostate cancer. [3,4] We implemented a screening strategy using nucleosome substrates to identify inhibitors of CBX2 binding to chromatin. Construct design and phosphorylation state of CBX2 were critical for successful implementation and execution of an HTS library screen. A rigorous screening funnel including counter and selectivity assays allowed us to quickly focus on true positive hit matter. Two distinct non-peptide-like chemotypes were identified and confirmed in orthogonal biochemical and biophysical assays demonstrating disruption of CBX2 binding to nucleosomes and direct binding to purified CBX2, respectively.
PRC1/2 复合物的失调在前列腺癌中的谱系可塑性中起着关键作用，并且可能需要维持神经内分泌表型。[1] CBX2 是经典 PRC1 复合物的关键组成部分，是一种表观遗传读取器，可识别组蛋白 3（H3K27me3）上的三甲基赖氨酸[2]，并且在转移性神经内分泌前列腺癌中过表达。[3,4] 我们使用核小体底物实施了一种筛选策略，以鉴定抑制 CBX2 与染色质结合的抑制剂。CBX2 的构建设计和磷酸化状态对于高通量筛选文库的成功实施至关重要。包括对照和选择性测定在内的严格筛选漏斗使我们能够快速关注真正的阳性命中物质。分别在正交生化和生物物理测定中鉴定并证实了两种不同的非肽样化学型，分别证明了对 CBX2 与核小体结合的破坏以及对纯化的 CBX2 的直接结合。
