Fig 2: Knock-down of MFN2 in ApoE−/− mice aggravated vascular senescence by affecting the expression of P53 and P21(A) To investigate the effect of Ang II stimulation on the expression of BCL6, MFN2, P53, and P21 proteins in mice aorta and (B) quantification.(B) Effects of shMfn2 followed by Ang II stimulation on MFN2, P53, and P21 protein expression in mice aorta and (D) quantification. In (B and D), each bar represents the mean ± SD (n = 3). Mean data are normalized to β-Actin. (∗p < 0.05, ∗∗p < 0.01).

Fig 3: WK369 was identified as a BCL6-BTB inhibitor. (A) HTRF assay screening schematic. (B) Chemical structural of compound WK369. (C) HTRF assay measured the effect of WK369 or FX1 blocked the interaction between BCL6-BTB and SMRT. (D) SPR sensorgram of WK369 binding to BCL6-BTB, with WK369 concentrations and calculated KD for binding shown. (E) Predicting the binding mode of WK369 with BCL6-BTB domain (PDB ID code: 5N1Z). The BCL6-BTB domain was shown as a cyan cartoon, and the inter residues were shown as green sticks.

Fig 4: WK369 inhibits ovarian cancer cell proliferation. (A) MTS assays from 48 h WK369 treatment assessed the viability of multiple ovarian cancer cell lines, as compared to normal human cell lines. (B) Antiproliferative activities of WK369 on different ovarian cancer cell lines and cytotoxicities on normal cell lines. (C) Statistical graph of activity difference of WK369 between high and low expression of BCL6 in different cell lines (right). (D-E) Cell viability assay of ES-2 and SKOV3 cells expressing BCL6 specific shRNA (shBCL6-1 and shBCL6-2) or Scramble shRNA (shScr) with indicated concentrations of WK369 treatment for 72 h. (F-G) Clonogenic assay of ES-2 and SKOV3 cells treated with the indicated concentrations of WK369 or FX1 for 7 days. A representative image of ES-2 and SKOV3 colonies is shown. (H-I) Anti-migration effects of WK369 or FX1 on ES-2 and SKOV3 after 24 h of treatment through transwell cell invasion assays. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, n.s. not significant by log-rank (Mantel-Cox) test.

Fig 5: BCL6 regulates endothelial cell senescence through MFN2(A) Protein expression levels and (C) quantification of P53, P21, and other genes after siMFN2 and siBCL6.(B) Protein expression levels and (D) quantification of P53, P21, and other genes after ovMFN2 and ovBCL6. In (C and D), each bar represents the mean ± SD for triplicate experiments (∗∗p < 0.01, ∗∗∗p < 0.001; #p < 0.05, ##p < 0.01).