Fortunately, the novel tumorigenic phenotype mediated by HMGA1 in the extracellular space, in conjunction with the observed association between the change in subcellular localization of HMGA1 and breast cancer progression, opens a number of applications in a wide range of settings, including prognostic assessment, monitoring treatment response, and development of new anticancer therapies (Figure 2). This evidence concerns the gene HMGA1 and breast cancer.