The baseline serum levels of CXCL1 were comparable between patients with different tumor localizations (iCCA, Klatskin, distal CCA and gallbladder cancer), T stage, M stage (who were still eligible for tumor resection), tumor grading or resection status (Figure S1A,B,D–F), while patients with node-positive disease (N1) showed slightly lower CXCL1 serum levels (Figure S1C). The gene discussed is CXCL1; the disease is gallbladder cancer.