ABCC2 and adenocarcinoma: Interestingly, while none of the above drugs increased ABCC1 transporter mRNA levels in adeno- (A549) or squamous (H520) carcinoma cell line aggregate tissues, ABCC2 were significantly up-regulated by all paclitaxel, doxorubicin and gemcitabine but only in adenocarcinoma cell line (A549) containing aggregate tissues (Fig. 4a, b).