Development of a new immunotoxin from part of the scorpion venom for the treatment of breast cancer

Breast cancer is one of the most cancers worldwide. It is associated with many problems due to the structural heterogeneity of the treatment process. Many patients with breast cancer (HER2) are positive. Current cancer treatment methods are not very effective in reducing mortality. However, immunotherapy is less effective in treating cancer and damages the body. An anti-cancer immunotoxin molecule that contais an immune component, which is an antibody or a binding component of an antibody, and the other part is a toxin, which is a lethal compound. The anti-HER2 receptor trastuzumab is derived from a single-stranded variable fragment (scFv) that binds to part of a scorpion toxin called neurotoxin Bmk. We investigated the physicochemical properties, secondary structure, and solubility of the chimeric protein using ProtParam and GORIV, PORCalc, PepCalc, and protein-sol, respectively. The structure and solubility of the model were evaluated using PROCHECK, protein-sol, and PepCalc. ALLERTOP server was used to predict sensitivity, and mRNA stability was assessed using RNAfold. Finally, docking of immunotoxin and HER2 was performed using ClusPro server. The results showed that the chimeric protein is a protein with a stable secondary structure in solution and a three-dimensional structure, which also has a stable mRNA and can bind to HER2. The results showed a stable and soluble protein with the desired binding ability to HER2, which made it a suitable immunotoxin candidate for the treatment of breast cancer whose safety needs to be evaluated in clinical phases.