NHS Lothian View Institution's Website 1 article published in JoVE Medicine The Use of Reverse Phase Protein Arrays (RPPA) to Explore Protein Expression Variation within Individual Renal Cell Cancers Fiach C. O'Mahony1, Jyoti Nanda1, Alexander Laird1, Peter Mullen2, Helen Caldwell3, Ian M. Overton4, Lel Eory4, Marie O'Donnell1,5, Dana Faratian6, Thomas Powles7, David J. Harrison1,2, Grant D. Stewart1 1Edinburgh Urological Cancer Group, University of Edinburgh, 2School of Medicine, University of St Andrews, 3Division of Pathology, University of Edinburgh, 4MRC Human Genetics Unit, MRC IGMM, University of Edinburgh, 5Department of Pathology, Western General Hospital, 6Breakthrough Breast Cancer Research Unit, University of Edinburgh, 7St Bartholomew's Cancer Institute, Experimental Cancer Medicine Centre, Queen Mary University of London RPPA enables the protein expression of hundreds of samples, printed on nitrocellulose slides to be interrogated simultaneously, using fluorescently labelled antibodies. This technique has been applied to study the effect of drug treatment heterogeneity within clear cell renal carcinoma.