Solute carrier organic anion transporter family member 1B3 (SLCO1B3) also known as organic anion-transporting polypeptide 1B3 (OATP1B3) is a protein that in humans is encoded by the SLCO1B3 gene.
OATP1B3 is a 12-transmembrane domain influx transporter. Normally expressed in the liver, the transporter functions to uptake large, non-polar drugs and hormones from the portal vein.
OATP1B3 has also been identified as a transporter aberrantly expressed in prostate cancer and implicated in prostate cancer progression. Increasing mRNA expression of OATP1B3 was also correlated to prostate cancer Gleason score.
In addition, lower expression of OATP1B3 mRNA was also detected in testicular cancer.
Small molecules that are transported by SLCO1B3 include: