Western blot was performed using Anti-Fumarase Monoclonal Antibody (GT7612) (Product # MA5-27746) and a 50 kDa band corresponding to Fumarate hydratase (FH) was observed across cell lines and tissues tested and was upregulated upon hydroxyurea treatment in HeLa and HCT 116 cells. Whole cell extracts (40 µg lysate) of untreated HCT 116 (Lane 1), hydroxyurea treated HCT 116 (Lane 2), untreated HeLa (Lane 3), hydroxyurea treated HeLa (Lane 4), K-562 (Lane 5), Jurkat (Lane 6), HL-60 (Lane 7) and tissue extracts (40 µg lysate) of Mouse Liver (Lane 8) and Rat Liver (Lane 9) were electrophoresed using NuPAGE™ 10% Bis-Tris Protein Gel (Product # NP0301BOX). 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 (1:1500 dilution) and detected by chemiluminescence with Goat anti-Mouse IgG (H+L) Superclonal™ Recombinant Secondary Antibody, HRP (Product # A28177, 1:10000 dilution) using the iBright FL 1000 (Product # A32752). Chemiluminescent detection was performed using SuperSignal™ West Dura Extended Duration Substrate (Product # 34076). The 25 kDa band detected in mouse liver corresponds to the circulating IgG commonly detected in mouse tissues.