BEND5, or BEN domain-containing protein 5, belongs to the BEN family of structural domains. It functions as a tumor suppressor gene, inhibiting cell proliferation. It is involved in multiple pathways such as the Notch signaling pathway and the peroxisome proliferator-activated receptor (PPAR) signaling pathway, playing a crucial role in tumor-related biological processes [1,2].

In breast cancer, low BEND5 expression is associated with advanced stage and shorter overall survival. Functional experiments show that BEND5 suppresses breast cancer growth and metastasis in vitro and in vivo by inhibiting Notch signaling through direct interaction with transcription factor RBPJ/CSL [1].

In lung adenocarcinoma, BEND5 expression is significantly decreased, and overexpression of BEND5 inhibits cell growth via the PPAR signaling pathway [2].

In colorectal cancer, hypermethylation of BEND5 is common, leading to down-regulation of its expression, and it is associated with poor overall survival; functional studies suggest that BEND5 inhibits cancer cell proliferation [3].

In conclusion, BEND5 is a significant tumor suppressor gene involved in the regulation of cell proliferation and multiple signaling pathways. Its dysregulation is associated with the development and prognosis of breast, lung, and colorectal cancers. Studies on BEND5 contribute to a better understanding of tumor-related biological processes and may provide potential targets for cancer therapy.