Fig 2: Schematic diagram depicting the mechanism by which miR-15b-5p affects the metastasis of GC. EVs from M2 macrophages can transfer miR-15b-5p to GC cells where it is upregulated and targets BRMS1 to inhibit its expression. The expression of DAPK1 is thus suppressed and the metastasis of GC cells is ultimately accelerated

Fig 3: BRMS1 mediates the destabilization of p300 and CBP upon iASPP removal and cisplatin treatment. (a) BRMS1 knockdown can rescue p300 and CBP levels in cisplatin-treated, iASPP-depleted cells. BRMS1 was transiently knocked down with siRNA in cells that expressed control or iASPP shRNA. Scrambled siRNA was transfected in parallel for control. 48 h after knockdown, the cells were either left untreated or incubated with cisplatin (24 h, 20 µM) followed by immunoblot analysis. (b) iASPP overexpression abrogates the interaction of BRMS1 and CBP in cisplatin-treated cells. HCT116 cells were transiently transfected with a BRMS1-GFP expression construct, alone or in combination with the iASPP-V5 expression plasmid. 24 h after transfection, the cells were treated with 20 µM cisplatin for 16 h and 20 µM MG132 for the last 4 h. Co-immunoprecipitation was performed using either an antibody for CBP or an isotype-matched control antibody (IgG). (c) Proposed mechanism of iASPP-mediated apoptosis. iASPP inhibits BRMS1-dependent proteasomal degradation of p300/CBP, thereby enhancing the induction of pro-apoptotic TAp73 target genes

Fig 4: BRMS1 represses the proliferation and invasion of GC cells via DAPK1 enhancement. AGS and MKN-45 cells were treated with sh-BRMS1, DAPK1, or both. A Western blot analysis of BRMS1, DAPK1, E-cadherin, N-cadherin, and Vimentin proteins in cells. B Colony formation of AGS and MKN-45 cells. C Invasion of AGS and MKN-45 cells measured by Transwell assay. D Matrix adhesion ability of AGS and MKN-45 cells. E HE staining analysis of the lung tissues of mice treated with sh-BRMS1, DAPK1, or both (scale bar = 50 µm). F Survival curve of nude mice treated with sh-BRMS1, DAPK1, or both. Each experiment was conducted three times independently. n = 8 for mice following each treatment. * p < 0.05, compared with AGS and MKN-45 cells or mice treated with sh-NC + Vector. # p < 0.05, compared with AGS and MKN-45 cells or mice treated with sh-BRMS1 + Vector

Fig 5: iASPP and BRMS1 modulate p300/CBP levels and apoptosis in melanoma. (a) Overexpression of iASPP partially re-establishes p300/CBP levels in melanoma cells. The iASPP-V5 expression plasmid or a GFP control vector was transiently transfected into Lox and A375 cells. 24 h after transfection, the cells were treated with 10 µM cisplatin for 24 h. Subsequently, total protein lysates were prepared and analyzed by immunoblotting. (b) Overexpression of iASPP enhances cisplatin-mediated apoptosis in melanoma cells. An expression plasmid for iASPP-V5 or the control vector pcDNA3 was transiently transfected into Lox and A375 cells. 24 h after transfection, the cells were treated with 20 µM cisplatin for 24 h, followed by harvest of the cells and staining with Annexin V/7-AAD solution. The percentages of unstained, Annexin V-positive and Annexin V/7-AAD-positive cells were determined using flow cytometry as in Figure 4c. Significance was calculated as in Figure 6d. (c) BRMS1 knockdown elevates p300 and CBP protein levels in Lox and A375 cells. BRMS1 was knocked down using siRNA. Scrambled siRNA was transfected in parallel as a control. 48 h after transfection, the cells were treated with 10 µM cisplatin, and immunoblots were stained for p300 and CBP. The Significance was determined by Student's t-test, and the P-values are shown by asterisks (*P-value <0.05)