Western blot was performed using Anti-PLK1 Monoclonal Antibody (3C11) (Product # MA5-17152) and a 62kDa band corresponding to Serine/threonine-protein kinase PLK1 was observed across cell lines tested. Whole cell extracts (30 µg lysate) of HeLa (Lane 1), SW480 (Lane 2), K-562 (Lane 3) and MDA-MB-231 (Lane 4) were electrophoresed using NuPAGE™ 4-12% Bis-Tris Protein Gel (Product # NP0322BOX). 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 (1:2000 dilution) and detected by chemiluminescence with Goat anti-Mouse IgG (H+L) Superclonal™ Recombinant Secondary Antibody, HRP (Product # A28177, 1:4000 dilution) using the iBright FL 1000 (Product # A32752). Chemiluminescent detection was performed using SuperSignal™ West Dura Extended Duration Substrate (Product # 34076).