BCL9

BCL9, or B-cell lymphoma 9 protein, is a transcriptional coactivator widely expressed in a variety of cells. It plays an important role in the Wnt/β-catenin signalling pathway, promoting the transcription of downstream genes by interacting with β-catenin and the TCF/LEF family of transcription factors, thereby affecting cell proliferation, differentiation and migration.The mechanism of action of BCL9 involves the binding of its helical structural domain to β-catenin, a process that is essential for the activation of the Wnt signalling pathway. The aberrant expression of BCL9 has been associated with the development of a variety of tumours, including colorectal and breast cancers, making it a potential target for tumour therapy. In a biological sense, BCL9 is not only involved in the regulation of tumour cells, but may also play a role in normal cell development and tissue homeostasis.