Regarding prostate cancer, PEPT1, as well as PEPT2 (SLC15A2), were found to be expressed in the prostate cancer cell lines PC-3 and LNCaP, respectively, and further controlled the cellular uptake of Gly-Sar and L-histidine, indicating their role in the tumor metabolism process (Tai et al., 2013). Here, SLC15A1 is linked to prostate cancer.