B-myb is a gene implicated in cell cycle and proliferation of breast cancer.

B-myb belongs to the myb family of transcription factors that include A-myb and c-myb. While A-myb and c-myb are tissue-specific, B-myb is broadly expressed in rapidly dividing cells of developing adult mammals. Results of our study showed that increased B-myb expression of was associated with the progression of breast cancer and that B-myb protein levels were significantly elevated in matched metastases. High B-myb levels also predict shorter overall survival of breast cancer patients. Moreover, B-myb stimulated transcription of target genes that promoted entry into the S and M-phases of the cell cycle, cell proliferation, migration and invasion in breast cancer. Taken together, our results strongly demonstrated that B-myb had a critical role in both cell cycle progression and tumorigenesis, and might serve as a novel potential target in the diagnosis and/or treatment of human breast cancer.