GPC3 and preeclampsia: In addition, a prior study has proposed that GPC3 may act as an anchor for placental protein 5 (PP5)/tissue factor pathway inhibitor-2 (TFPI-2) on placental villi, and a decrease in GPC3 expression in patients with preeclampsia may explain the increased levels of PP5/TFPI-2 in the serum of these patients [34].