Preparation and radiolabeling of Iranian Androctonus crassicauda scorpion venom with technetium-99m as a new agent for cancer diagnostic and therapeutic purposes.

One of the innovative methods in cancer treatment with fewer side effects is the use of active principles produced by animals and microorganisms to generate new drugs with diagnosis and treatment capability for cancer. Androctonus crassicauda scorpion venom has high potential as an anti-tumor agent and has the ability to interfere with human physiology but is still unknown. Therefore, labeling venom with radionuclides is very important to study the biological distribution of toxins for diagnostic and therapeutic purposes of various diseases, especially cancer. In this research, the toxic fraction of this venom was labeled with ^99mTc. The radiochemical purity of the labeled toxic fraction was obtained by using chromatographic systems. Animal biodistribution studies were performed after injecting the labeled compound into normal rats and 4T1 breast cancer-bearing mice. The radiochemical purity of 90% was obtained for labeled compound. Biological distribution studies showed relatively rapid clearance of the labeled compound from the blood circulation system. The accumulation of the labeled compound in the liver and kidney was the highest among the organs, which could indicate the possibility of toxin excretion metabolism from liver and the kidneys. The accumulation rate of the labeled compound after 15 min was 7% in the breast cancer mass, and the ratio of the distribution of the labeled compound in the breast cancer mass to the blood was 155% at 15 min post injection. The study results indicated that scorpion venom labeling with ^99mTc could be a useful tool for the biodistribution and kinetic studies of the venoms for clinical use. On the other hand, based on the results of the biological distribution of the labeled compound in tumor-bearing mice, the ^99mTc-venom complex can be used as an imaging agent to diagnose breast cancer. Moreover at the same time, with some measures, it can be used as a therapeutic agent for breast cancer with more consideration. We hope that the results of this study will be a step in the future for the clinical diagnostic and therapeutic purposes of cancer using natural products. [ABSTRACT FROM AUTHOR]