Considering the relationship between ABC transporters and cancer progression is not fully established, through the evaluation of TGF-β-induced EMT effects over the expression and function of ABCB1 and ABCC1 transporters in the A549 cell line, we would be able to establish an implication of the MDR phenotype acquisition in metastatic tumors and identify potential therapeutic targets. The gene discussed is ABCG2; the disease is cancer.