The invention provides compositions and methods for detecting and/or modulating TOX3 gene expression and/or biological activity. Such compositions and methods find utility in the detection and/or treatment of certain subsets of cancers, e.g. breast cancer. In particular, the inventive compositions and methods are drawn to production and use of anti-TOX3 antibodies and TOX3 nucleic acids for both detection and modulation of TOX3. The invention also provides for pharmaceutical compositions and methods for the modulation of TOX3 in a subject in need thereof. Further aspects of the invention relate to transgenic mice that either over-express or inducibly express TOX3.
