Western blot was performed using Anti-IQGAP1 Polyclonal Antibody (Product # PA5-96385) and a 189 kDa band corresponding to IQGAP1 was observed across all cell lysates tested. Whole cell extracts (60 µg lysate) of HaCaT (Lane 1), THP-1 (Lane 2), K-562 (Lane 3), HEK-293 (Lane 4) and A-431 (Lane 5) were electrophoresed using NuPAGE™ 3-8% Tris-Acetate Protein Gel (Product # EA0378BOX). Resolved proteins were then transferred onto a nitrocellulose membrane (Product # IB23001) by iBlot® 2 Dry Blotting System (Product # IB21001). The blot was probed with the primary antibody (1:1000 dilution) and detected by chemiluminescence with Goat anti-Rabbit IgG (Heavy Chain) Superclonal™ Recombinant Secondary Antibody, HRP (Product # A27036,1:10000 dilution) using the iBright™ FL1500 Imaging System (Product # A44115). Chemiluminescent detection was performed using SuperSignal™ West Pico PLUS Chemiluminescent Substrate (Product # 34580). An uncharacterized band (*) was observed at ~60 kDa in HEK-293 and A-431 cell lysates.