ABCG2 and intrahepatic cholangiocarcinoma: However, these bands were still present after ABCG2-specific siRNA transfection, thus suggesting that these bands are derived from other proteins not related to ABCG2 and that they are not important for ICC, because no immunostaining was observed in MDADMSO and only weak immunostaining was detected in a small fraction of LoVoparental cells.