TOKYO — As cancer research has continued over the last few decades, much of the work has focused on treatments like radiation and experimental drugs. Scientists in Japan say they may have uncovered a new method of killing cancer cells, with a more environmentally-friendly approach. Their study reveals a method of combining organic compounds to create a natural cancer drug with few side-effects.
The team from the Tokyo University of Science focused on weaponizing organic compounds called phenazines. These substances are a group of nitrogen-filled heterocycles, or compounds made up of at least two elements. While there are about 100 phenazines which occur in nature, scientists are able to synthesize over 6,000 more in the lab.
Out of all these organic compounds, the study reveals N-alkylphenazin-1-ones (phenazinones) have antibacterial, antifungal, and cytotoxic properties. Cytotoxicity is the key in terms of fighting cancer. Researchers say if a cytotoxic compound can be directed to target cancer cells, they can destroy the disease.
“Pyocyanin, lavanducyanin, lavanducyanin-derived WS-9659 A, WS-9659 B, and marinocyanins A and B, all different types of phenazines, show cytotoxic activities, against cancer cells. However, these compounds are difficult to derive from their natural sources such as bacteria,” study leader Prof. Kouji Kuramochi says in a university release.
Making cancer drugs the eco-friendly way
The Japanese team experimented with several ways of synthesizing these compounds. Researchers tried methods including halogenation, a process of adding substances like chlorine and bromine, and oxidative condensation, the addition of an oxidant and water molecules. The experiments successfully synthesized new N-alkyl-2-halophenazin-1-ones.
From these compounds, researchers discovered specific phenazinones called 2-chloropyocyanin have a high cytotoxicity when introduced to lung cancer cells. Aside from having natural anticancer properties, the team is praising the fact that the synthesizing process only involves oxygen.
“We have established a highly versatile synthetic method that is simple and can be applied to the synthesis of many natural products,” Prof. Kuramochi explains. “Since the oxidative coupling reaction proceeds only with oxygen, it is an environmentally friendly synthetic method.”
Study authors add the eco-friendly process avoids setbacks seen in other compound-forming techniques which create other, undesirable particles. The team says their new compounds are over four times more toxic to cancer cells than normal cells. This makes them ideal as a potential cancer treatment since they have few side-effects for patients.
Prof. Kuramochi and the team are preparing to see how their phenazinones work in animal and clinical trials.
The study appears in the journal American Chemical Society Omega.