PROTACEZH2 Degrader-9 is an orally active EZH2 PROTAC degrader, operating through the ubiquitin-proteasome pathway. It effectively reduces the PRC2 core subunit and potently inhibits H3K27me3 without affecting common CRBN neo-substrates, showing selectivity towards GSPT1 and IKZF1/3. The compound exhibits strong antiproliferative effects on various cancer cell lines by inducing cell cycle arrest and apoptosis (apoptosis). Additionally, PROTACEZH2 Degrader-9 reverses PRC2-mediated gene silencing and suppresses the activation of EZH2 non-catalytic target genes. This compound is applicable in research on leukemia, lymphoma, and non-small cell lung cancer.

PROTAC EZH2 Degrader-9 (compound 5g) induces EZH2 degradation in MV4–11 cells through the ubiquitin-proteasome system linked with E3 ligase CRBN when applied at 0-10 μM for 0-48 hours. When used for 72 hours, it displays antiproliferative effects on various cancer cell lines, including MV4–11, MOLM-13 (leukemia), SU-DHL-4, SU-DHL-6 (large B-cell lymphoma), A549, NCI-H1299, and NCI-H1703 (small cell lung cancer), with IC50 values of 2.22, 2.60, 6.35, 9.23, 19.26, 4.41, and 6.35 μM, respectively. The activity shows a significant negative correlation with the expression levels of EZH2 (Pearson correlation coefficient r = -0.860, p = 0.013) and CRBN (r = -0.726, p = 0.049). At a concentration of 10 μM for 24 hours, the compound mediates antiproliferative activity by degrading EZH2 and other PRC2 subunits in NCI-H1299, NCI-H1703, MOLM-13, and A549 cells. Over 72 hours, treatment with 10 μM results in the differential expression of 1,314 genes, with an equal number of upregulations and downregulations, affecting biological processes such as DNA repair and mitotic cell cycle, particularly influencing the G2/M phase transition. It enriches differentially expressed genes in cancer-related pathways, especially those controlling the cell cycle, negatively impacting G2/M checkpoint pathways while positively enriching apoptotic pathways. The compound (0.12-10 μM, 24-72 hours) arrests the MV4-11 cell cycle at the G0/G1 phase, preventing progression to the S and G2/M phases, and induces apoptosis in a dose-dependent manner. Furthermore, at 1-10 μM for 72 hours, it alters gene expression regulated by both catalytic and non-catalytic activity of EZH2 in MV4-11 cells.