AT1R-Specific Ligand Angiotensin II as a Novel SPECT Agent for Hepatocellular Carcinoma Diagnosis.
Hepatocellular carcinoma (HCC) is characterized by a high mortality and early diagnosis and treatment are critically needed. Ang II type 1 receptor (AT1R) has recently emerged as a potential molecular target for cancer diagnosis and intervention. Here, we labeled angiotensin II (Ang II), an AT1R ligand that is overexpressed in various solid cancers, with the near-infrared fluorescent dye, MPA, and radionuclide technetium-99m, and evaluated its capacity for HCC detection. These analyses were done in vitro using HepG2 (AT1R-positive) and BxPC3 (AT1R-negative) cell lines, and in vivo using a subcutaneous and orthotopic xenograft mouse model by fluorescence and SPECT imaging. Both Ang II-PEG4-MPA- and [99mTc]Tc-HYNIC-PEG4-Ang II-bound AT1R exhibited a high affinity in vitro and [99mTc]Tc-HYNIC-PEG4-Ang II displayed an acceptable level of in vitro stability in rat plasma and whole blood. In vivo imaging revealed excellent specific tumor-targeting in HepG2 mouse xenografts models. In vitro and in vivo competition experiments revealed specific Ang II-PEG4-MPA and [99mTc]Tc-HYNIC-PEG4-Ang II uptake by HepG2 cells and tumors. Altogether, AT1R-positive tumors were successfully detected via fluorescence and SPECT imaging using Ang II-PEG4-MPA and [99mTc]Tc-HYNIC-PEG4-Ang II, respectively. Given their superior targeting capacity, Ang II-PEG4-MPA and [99mTc]Tc-HYNIC-PEG4-Ang II are promising tools for HCC detection and warrant clinical translation.
['Tu|Yuanbiao|Y|', 'Liu|Zicun|Z|', 'Wang|Fang|F|', 'Liu|Peifei|P|', 'Tao|Ji|J|', 'Li|Changsheng|C|', 'Han|Zhihao|Z|', 'Li|Zhaolun|Z|', 'Ma|Yi|Y|', 'Gu|Yueqing|Y|0000-0003-1315-4618']
D000804:Angiotensin II D000818:Animals D006528:Carcinoma, Hepatocellular D045744:Cell Line, Tumor D008024:Ligands D008113:Liver Neoplasms D051379:Mice D051381:Rats D015899:Tomography, Emission-Computed, Single-Photon
angiotensin II hepatocellular carcinoma AT1R near-infrared fluorescence SPECT-CT orthotopic tumor