Because the technique avoids indiscriminate tissue damage, it is expected to significantly affect cancer treatment.
Besides effectively killing cancer cells, a big challenge for cancer chemotherapy is how to minimize toxic side effects on the body. Drugs that can damage cancer cells can damage noncancerous cells, and the negative side effects of chemotherapy can cause permanent and debilitating damage.
Current methods to reduce these side effects include selective delivery of antineoplastic drugs to cancer tissue (drug delivery) and conversion of nontoxic compounds (precursors) to proximal toxic compounds. cancerous tissue.
Katsunori Tanaka at RIKEN CPR, who led the new research, has developed a method of activating the precursor using an in vivo transition metal catalysis.
When a catalyst is injected into an organism, it usually has no effect because it is destroyed by antioxidants such as glutathione. By placing the transition metal catalysts inside special vesicles inside the protein, Tanaka and his colleagues avoided this problem and stabilized the catalytic function in vivo, thus ensuring that the reaction Chemical reactions can take place effectively in the body.
The catalyst needs to find its way to the cancer selectively for this technique to work. As in previous studies, the team targeted the cancer-causing catalyst by attaching chains of cancer-linking sugar molecules to the surface of carrier proteins.
Using these techniques, Tanaka’s team was successful in inhibiting cancer growth and metastasis and reducing side effects. The new study is a proof of concept in which mice are treated for cancer by actually gathering anti-cancer drugs inside the body near cancer cells.
“We’ve used similar methods in the past to attach anti-cancer drugs to tumors, but here we were able to avoid introducing any toxic drugs into the body,” said Tanaka.
Noting that the basic skeleton of most anticancer drugs contains a benzene ring, the researchers started by creating the benzene ring inside the body using transition metal catalysts. “No one believes that artificially synthesizing the benzene ring inside the body is better, but I am confident that we can do it based on our previous achievements,” says Tanaka.
Using a transition metal catalytic complex designed to selectively deliver to cancer tissues, they successfully created the benzene ring needed for cancer drugs in the vicinity of cancer cells. letters.
By taking non-toxic substances and just combining them together to form an anti-cancer drug that works at the tumor site, they saw a 1000-fold increase in the drug’s cancer-suppressive activity.
Using only the ingredients needed for the drug and an intravenous transition metal catalyst, cancer growth was inhibited without side effects such as weight loss.
This is the first time that an active anti-cancer drug has been produced locally and effectively fights cancer by injecting its components through a vein.
In addition to benzene, the method developed in this study is expected to allow the synthesis of many other types of molecules inside the body. It is hoped that this type of chemotherapy will become a useful treatment platform for the future of cancer treatment.
“Many cancer patients are dying from side effects of treatment,” says Tanaka. We believe that technology that attacks cancer cells effectively, without side effects, will be able to save lives.”
“This approach will also allow us to rethink the use of compounds that have not been used before because they are too toxic to be delivered to the whole body. They can now be synthesized in situ. tumors without affecting healthy tissue. We believe this is a paradigm shift for pharmaceuticals and drug discovery.”