Bcl6b, also known as BAZF, ZBTB28, and ZNF62, operates as a sequence-specific transcriptional repressor in the nucleus. It plays crucial roles in multiple biological functions, including tumor suppression, immune response, stem cell self-renewal, and vascular angiogenesis [2]. It is involved in pathways such as the VEGF-Notch signaling balance, which is important for endothelial cell activation [1].

In animal models, Bcl6b-deficient endothelial cells showed Notch signal activation and attenuated cord formation by blocking the VEGF-VEGFR2 signaling pathway. Bcl6b-targeting small-interfering ribonucleic acid decreased choroidal neovascularization lesions and suppressed ocular edema in the neuroretina, indicating its role in ocular vascular diseases [1]. In mice, knockout of Bcl6b worsened gastric cancer and aggravated the inflammatory response, while re-activation of Bcl6b impeded inflammatory amplification and gastric cancer development [3]. Also, Bcl6b transgenic rats were less susceptible to hepatocellular damage, inflammation, and fibrosis [4].

In conclusion, Bcl6b is essential in regulating various biological processes and disease conditions. Gene knockout models, especially in mice, have revealed its significant roles in ocular vascular diseases, gastric cancer, and liver-related pathologies. These findings suggest that Bcl6b could be a potential therapeutic target for these diseases.

References:

1. Tanaka, Miruto, Nakamura, Shinsuke, Sakaue, Tomohisa, Higashiyama, Shigeki, Hara, Hideaki. 2023. BCL6B Contributes to Ocular Vascular Diseases via Notch Signal Silencing. In Arteriosclerosis, thrombosis, and vascular biology, 43, 927-942. doi:10.1161/ATVBAHA.123.318987. https://pubmed.ncbi.nlm.nih.gov/37078291/

2. Li, Zhonghao, Wu, Wei, Li, Qiushi, Xiao, Qingzhong, Yan, Yi. 2024. BCL6B-dependent suppression of ETV2 hampers endothelial cell differentiation. In Stem cell research & therapy, 15, 226. doi:10.1186/s13287-024-03832-y. https://pubmed.ncbi.nlm.nih.gov/39075623/

3. Cai, Wang-Yu, Lin, Ling-Yun, Wang, Lin, Chen, Mao-Li, Luo, Qi-Cong. 2019. Inhibition of Bcl6b promotes gastric cancer by amplifying inflammation in mice. In Cell communication and signaling : CCS, 17, 72. doi:10.1186/s12964-019-0387-6. https://pubmed.ncbi.nlm.nih.gov/31288844/

4. Wang, Weilin, Huang, Pengfei, Wu, Panyisha, Zhou, Lin, Zheng, Shusen. . BCL6B expression in hepatocellular carcinoma and its efficacy in the inhibition of liver damage and fibrogenesis. In Oncotarget, 6, 20252-65. doi:. https://pubmed.ncbi.nlm.nih.gov/25970780/