Evaluation and Simulation of Docking Peptide Labeled with Technetium-99m (Tc-99m) with Human Epidermal Growth Factor Receptor 2 (HER2) in HER2-Positive Breast Cancer Cells

Breast cancer is the first fatal disease in women and the second leading cause of death in humans, after heart disease. In approximately 20% of these patients, breast cancer cells have a higher-than-normal level of a protein called human epidermal growth factor receptor 2 (HER2) on their surface. These cancers, called HER2-positive, tend to grow and spread faster than other breast cancers.

This study aimed to evaluate the binding of the peptide LTVSPWY labeled with the HER2 receptor compared to the non-labeled peptide and simulate its docking.

The LTVSPWY peptide was first labeled with the 99-radioactive technetium (Tc-99m) and optimized for molecular docking with the HER2 receptor in HyperChem software. Then, the HEX 6 software was used to check how the compounds were connected to the active site of the HER2. Finally, data was analyzed by HEX, LIGPLOT, and other programs.

During docking in HEX, the labeled peptide showed a good link with the HER2 protein receptor. The energy of this kind of transplantation was higher than the nonlabeled peptide bond with the HER2 protein receptor. In fact, this combination had the lowest level of connection energy with the receptor, which reflects the success of docking.

In the analysis of the post-docking data, we observed the ligand was connected to the HER2 receptor from 5 major sites at different intervals, indicating a suitable bond to the receptor ligand.