Recent studies have shown that HSP72 and gp96 are highly expressed in cancer tissues and have been used as prognostic markers in some tumors, such as hepatocellular carcinoma, gastric cancers, colonic tumors, breast cancers, and lung cancers, which have also been verified to be associated with the development and progression of the above-mentioned carcinomas [8–12]. This evidence concerns the gene HSP90B1 and breast cancer.