HSPA5 and cancer: Importantly, GRP78 is up-regulated and preferentially expressed on the cell surface of tumor cells and minimally in normal cells, making it an attractive target for cancer-specific therapy, including aggressive breast cancer (Arap et al, 2004; Sato et al, 2010; Liu et al, 2013; Lee, 2014; Dobroff et al, 2016; D’Angelo et al, 2018).