Repurposing an atherosclerosis targeting peptide for tumor imaging

Area of Science:

• Oncology
• Cardiovascular Research
• Biomedical Imaging

Background:

• Cancer and atherosclerosis share pathological features like uncontrolled cell proliferation and inflammation.
• A peptide (CTHRSSVVC) known to bind atherosclerotic lesions was investigated for tumor-homing capabilities.

Purpose of the Study:

• To evaluate the tumor-targeting potential of the CTHRSSVVC peptide in a preclinical cancer model.
• To assess if a peptide targeting atherosclerosis could be repurposed for cancer imaging.

Main Methods:

• Synthesis of N-terminally sulfo-Cy5 labeled CTHRSSVVC peptide.
• In vitro evaluation of macrophage binding using flow cytometry and immunofluorescence.
• In vivo tumor targeting assessment in 4T1 tumor-bearing mice using optical imaging and ex vivo confocal microscopy.

Main Results:

• The sulfo-Cy5-CTHRSSVVC peptide showed no selective binding to macrophages in vitro.
• In vivo, the peptide accumulated in 4T1 tumors, achieving a tumor-to-normal tissue ratio of 7.21 ± 1.44 at 2 hours post-injection.
• Ex vivo analysis indicated peptide accumulation in the tumor stroma, specifically in regions with spindle-shaped cells.

Conclusions:

• The CTHRSSVVC peptide demonstrates in vivo tumor accumulation, suggesting potential for tumor imaging.
• Further research is needed to identify the specific molecular target of the CTHRSSVVC peptide within the tumor microenvironment.