EGFR and colorectal carcinoma: None of the tested therapeutic antibodies–the anti-VEGF antibody Bevacizumab and the anti-EGFR antibody Cetuximab are frequently used in CRC treatment; anti-CD20 Rituximab (in clinical use for treatment of leukaemia) served as a negative control–had any effect on cell viability even at concentration of 20 μg/ml (data not shown).