Triple negative (TN) breast cancer is defined by the lack of estrogen, progesterone and Her2/neu receptors, and has a worse overall outcome than other breast cancer subtypes due to limited treatment options and high rates of metastatic spread. Recent advances in understanding the biology of TN breast cancer have identified two features, hypoxia (low oxygen) and defects in error-free DNA repair, that contribute to its aggressive biology and poor prognosis. This study will evaluate the therapeutic potential, in preclinical models of TN breast cancer, of new drugs that simultaneously target hypoxia and defects in error-free DNA repair. These drugs were discovered by our laboratory and are currently in advanced preclinical or clinical development. Identification of an effective compound in this study will lead to subsequent clinical studies to evaluate efficacy in TN breast cancer patients.