Whilst OATP expression in the normal human brain is low,34,35 previous reports suggest that OATPs are expressed on astrocytes with a key role in thyroxine transport.13,34,36 Therefore, given the glial origin of GBM, we hypothesized that OATPs would be expressed in GBM tumor cells. The gene discussed is SLCO1A2; the disease is glioblastoma.