TBX3 and breast cancer: The recent finding that TBX3 alterations may be key driver mutations in breast cancer, and the suggestion that altered (probably increased) TBX3 function may be associated with at least some cases of familial breast cancer [26], adds particular significance to the potential of TBX3 as an important regulator of breast cancer progression, and added urgency to a better understanding of its role in the malignancy of breast cancer.