The objectives were to (1) characterize the expression of RGS10 in freshly resected breast cancer and adjacent normal breast tissues; (2) determine the prognostic significance of RGS10 expression in patients with breast cancer; and (3) explore the role of RGS10 and upstream effectors in tumor progression and metastasis in breast cancer cells in vitro and in vivo. Here, RGS10 is linked to neoplasm.