A recent clinical study in prostate cancer patients showed positive correlation between MCT1 expression and lactate labeling,3 and we have shown previously in the EL4 tumor model that the MCT inhibitor, α‐Cyano‐4‐hydroxycinnamic acid (injected at 150 mg kg1), produced a 40% decrease in label exchange.30 Here, SLC16A1 is linked to prostate carcinoma.