Dbet1

Thalidomide (Tokyo Chemical Industry), pomalidomide (Sigma-Aldrich), lenalidomide (FUJIFILM Wako), 5-hydroxyThalidomide (prepared according to a previously published method^{64 (link)}), dBET1 (MedChemExpress), ARV-825 (MedChemExpress), indisulam (BLD Pharmatech), MG132 (Peptide Institute), and MLN4924 (Chemscene) were dissolved in DMSO (FUJIFILM Wako) at 2–100 mM and stored at −20 °C as stock solutions. All drugs were diluted 1000-fold for in vivo experiments or 200-fold for in vitro experiments.

GBM cells (2 × 10³/well) were cultured overnight in 96-well plates; GBM cells were treated with GNE987, JQ1, ARV825, dBET1 (MedChemExpress, USA) or DMSO (Sigma, USA) for 3 days,5 days or 7 days, and the absorbance of a 96-well plate was measured using a microplate reader with CCK8 (Dojindo, Japan). Cell viability and proliferation rates were calculated using GraphPad Prism8.4.0.

Thalidomide (T2524, Tokyo Chemical Industry), pomalidomide (P2074, Tokyo Chemical Industry), lenalidomide (#126-06733, FUJIFILM Wako Pure Chemical Corporation, Osaka, Japan), Thalidomide-O-COOH (HY-103597, MedChemExpress, NJ, USA), CC-122/Avadomide, (HY-100507, MedChemExpress), CC-220/Iberdomide, (HY-101291, MedChemExpress), CC-885 (HY-101488, MedChemExpress), FPFT-2216 (HY-145319, MedChemExpress), biotin-Thalidomide (#913979, Sigma-Aldrich, MA, USA), dBET1 (HY-101838, MedChemExpress), dBET6 (HY-112588, MedChemExpress), ARV-825 (HY-16954, MedChemExpress), MD-224 (HY-114312, MedChemExpress), ARV-110 (HY-138641, MedChemExpress), and MG132 (3175-v, Peptide Institute Inc., Osaka, Japan) were purchased. The procedure and physical data of Thalidomide derivatives and PROTACs synthesised in this study are described in Supplementary Information. All drugs were dissolved in dimethylsulfoxide (DMSO, #045-24511; FUJIFILM Wako Pure Chemical Corporation) at 10–200 mM, stored at −30 °C as stock solutions, and diluted 1,000-fold for in vivo experiments or 100–200-fold for in vitro experiments.