PGP and non-small cell lung carcinoma: ABCB1 (ATP binding cassette, subfamily B, member 1), also known as multidrug transporter (MDR1) or P-glycoprotein (P-gp), which has been shown to be present in CFZ-resistant cells26,27, is rather poorly expressed in all four NSCLC lines used in the present study (Fig. 5A).