In HCC, PYCR1 drives tumor growth and metastasis by upregulating IRS1; the protein and mRNA levels of PYCR1 and IRS1 (detected by IHC and qPCR, respectively) can serve as a potential diagnostic combination, but their clinical application still requires large-scale trials to verify their specificity and sensitivity. The gene discussed is IRS1; the disease is hepatocellular carcinoma.