Fig 2: In silico modeling of the lead compound 6 in the DDB1–CRBN–CC-885–GSPT1 complex (PDB: 5HXB). (A) Compound 4 (gray sticks) relative position to 6 (green sticks) docked into the CRBN structure before (gray cartoon) and after 2 μs of MD simulation (green cartoon); (B) MD simulations predict compound 6 to be accommodated in a narrow hydrophobic pocket formed by CRBN residues (gold sticks) and GSPT1 residues (gray sticks).

Fig 3: Immunoblots for GSPT1 and IKZF1 proteins after the treatment with increasing concentrations of compounds 6 and 7 of: MV4-11 cells over 4 (A) and 24 h (B) and MHH-CALL-4 cells over 4 (C) and 24 h (D). Degradation values were calculated using quantified band intensities from immunoblots and DC50 values calculated based on the average of at least two independent experiments.

Fig 4: MV4-11 parental cell line and cells stably expressing degradation-resistant GSPT1(G575N)-FLAG: (A) effect of the treatment with increasing concentrations of 6 and 7 over 3 days on proliferation of MV4-11 parental cells or cells stably expressing GSPT1(G575N)-FLAG; (B) immunoblots for GSPT1 and IKZF1 proteins after the treatment with increasing concentrations of compounds 6 and 7 of MV-411 parental cells or cells stably expressing GSPT1(G575N)-FLAG over 24 h.

Fig 5: The role of GSPT1 and WNT3A and the regulation of lnc-SNHG16 and miR-128 on WNT pathway. (A) Effect of shR-GSPT1 and shR-WNT3A on cell viabilities was determined by CCK8 in C33A and HeLa. (B) Relative colony formation rates of C33A and HeLa cells transfected with shR-GSPT1 and shR-WNT3A were determined. (C) Flow cytometric analysis showed that shR-GSPT1 and shR-WNT3A lead to an increase in G0/G1 phase of C33A and HeLa cells. (D) Flow cytometric assay showed that shR-GSPT1 and shR-WNT3A significantly promoted the apoptosis rate of C33A and HeLa cells. (E and F) Transwell assays revealed that shR-GSPT1 and shR-WNT3A suppressed the invasion and migration ability. (G) Western blot analysis of the indicated protein expression levels following transfection with shR-GSPT1 and shR-WNT3A in HeLa cells. (H and I) Knockdown of GSPT1 and WNT3A inhibited tumor growth rate and tumor weight. (J) IF assay showed the distribution of β-catenin in HeLa cells transfected with the indicated plasmids. (K) Western blot showed the protein levels transfected with the indicated plasmids in HeLa cells. Experiments were performed 3 times, and data are presented as means ± SD.*P<0.05; **P<0.01; ***P<0.001; ns, not significant.