To evaluate whether TAT-ΔNS3/4A-124I-FITC can be used to visualize NS3/4A activity in vivo, the NS3/4A-HCC36 or HCC36 tumor-bearing mice were intravenously injected with TAT-ΔNS3/4A-124I-FITC and imaged at 2, 4, and 6 h. The gene discussed is KRAS; the disease is neoplasm.