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Li, H.-y.

Publications and source records attributed to Li, H.-y..

2 recordsLinked to original sources

Destruction of DNA-binding proteins by programmable O'PROTAC: Oligonucleotide-based PROTAC

DNA-binding proteins including transcription factors (TFs) play essential roles in gene transcription and DNA replication and repair during normal organ development and pathogenesis of diseases such as cancer, cardiovascular disease and obesity, deeming to be a large repertoire of attractive therapeutic targets. However, this group of proteins are generally considered undruggable as they lack an enzymatic catalytic site or a ligand binding pocket. PROteolysis-TArgeting Chimera (PROTAC) technology has been developed by engineering a bifunctional small molecule chimera to bring a protein of interest (POI) to the proximity of an E3 ubiquitin ligase, thus inducing the ubiquitination of POI and further degradation through proteasome pathway. Here we report the development of Oligonucleotide-based PROTAC (OPROTACs), a class of noncanonical PROTACs in which a TF-recognizing double-stranded oligonucleotide is incorporated as a binding moiety of POI. We demonstrate that OPROTACs of ERG and LEF1, two highly cancer-related transcription factors selectively promote degradation of these proteins and inhibit their transcriptional activity in cancer cells. The programmable nature of OPROTACs indicates that this approach is applicable to destruct other TFs. OPROTACs not only can serve as a research tool, but also can be harnessed as a therapeutic arsenal to target DNA binding proteins for effective treatment of diseases such as cancer.

biochemistry

Spatiotemporal Dynamics of Intra-tumoral Dependence on NEK2-EZH2 Signaling in Glioblastoma Cancer Progression

The highly lethal brain cancer glioblastoma undergoes dynamic changes in molecular profile and cellular phenotype throughout tumor core establishment and in primary-to-recurrent tumor progression. These dynamic changes allow glioblastoma tumors to escape from multimodal therapies, resulting in patient lethality. Here, we identified the emergence of dependence on NEK2-mediated EZH2 signaling, specifically in therapy-resistant tumor core-located glioblastoma cells. In patient-derived glioblastoma core models, NEK2 was required for in vivo tumor initiation, propagation, and radio-resistance. Mechanistically, in glioblastoma core cells, NEK2 binds with EZH2 to prevent its proteasome-mediated degradation in a kinase-dependent manner. Clinically, NEK2 expression is elevated in recurrent tumors after therapeutic failure as opposed to their matched primary untreated cases, and its high expression is indicative of worse prognosis. For therapeutic development, we designed a novel NEK2 kinase inhibitor CMP3a, which effectively attenuated growth of murine glioblastoma models and exhibited a synergistic effect with radiation therapy. Collectively, the emerging NEK2-EZH2 signaling axis is critical in glioblastoma, particularly within the tumor core, and the small molecule inhibitor CMP3a for NEK2 is a potential novel therapeutic agent for glioblastoma.

cancer biology