The 111In-DTPA-AHNP-PEG-treated group showed higher ratio in T/M and T/B compared to 111In-DTPA-treated group (Fig. 8b), indicating that 111In-DTPA-AHNP-PEG could target to HER2-expressed gastric tumor tissues and consequently improve the imaging efficacy. The gene discussed is ERBB2; the disease is gastric neoplasm.