SLCO5A1 and breast neoplasm: Furthermore, there is a general lack of studies on a potential prognostic effect of OATP5A1 for cancer patients; however, SLCO5A1 expression has been reported in a number of tumors and the localization of the OATP5A1 protein has been shown in liver and breast tumors (Kindla et al., 2011; Wlcek et al., 2011).