HSP90B1 and breast cancer: Analysis of the subgroups based on the coexpression of GP96 and AR revealed an association with HER2 status (p < 0.001), ER and PR status (both p < 0.001), number of metastatic sites (p = 0.030), and BC surrogate molecular subtypes (p < 0.001) while showing no significant association with other clinicopathological factors.