To test whether paclitaxel, doxorubicin and gemcitabine drugs that are frequently applied in combination therapy can affect ABC transporter transcription, 3D co-cultures were created using primary human lung fibroblasts (NHLF) and the adenocarcinoma cell line A549 or the squamous cell carcinoma cell line H520. Here, ABCG2 is linked to adenocarcinoma.