In addition, some studies point out that the up-regulation of EMT-associated transcriptional factors, containing Slug, Zeb1 and Twist1, can directly lead chemotherapy in breast cancer and NSCLC through the ATP-binding cassette (ABC) transporter family of proteins (ABCB1, ABCC1 and ABCG2) (35). Here, ABCG2 is linked to non-small cell lung carcinoma.