Researchers have identified a potent new anti-cancer compound isolated from a toxic blue-green algae found in the South Pacific - somocystinamide A (ScA).
The study, led by Dennis Carson M.D., professor of medicine and director at UCSD, will be published online in Proceedings of the National Academy of Science.
"We are excited because we have discovered a structurally unique and highly potent cancer-fighting compound," said Dwayne G. Stupack, associate professor of pathology at the Moores UCSD Cancer Center.
"We envision it will be perfect for emerging technology, particularly nanotechnology, which is being developed to target cancerous tumors without toxic side effects," Stupack added.
The laboratory of William Gerwick at Scripps Institution of Oceanography found the ScA compound in the cyanobacteria L. Majuscula, also known as 'mermaid's hair,' gathered off the coast of Fiji in the South Pacific.
Researchers from UCSD's Cancer Center, School of Medicine, Skaggs School of Pharmacy and Pharmaceutical Sciences, and Scripps worked to identify, screen and test marine compounds in vitro and in vivo.
They found that ScA inhibits neovascularization, the formation of blood vessels that feed tumors, and also had a direct impact on tumor cell proliferation.
"The compound isn't toxic to the cyanobacteria itself, but activates a 'death pathway', present in our cells. When the cells of the blood vessels that feed tumors become activated and proliferate, they become especially sensitive to this agent," Stupack said.
In the work, Gerwick noted that if a normal-sized swimming pool full of cancer cells were treated with ScA, it would take only three milligrams to kill all of the cancer cells.
Wolf Wrasidlo, Ph.D., senior author at the Moores UCSD Cancer Center and first author of the work, said that the unique structure of this compound lends itself very well to nanotechnology, because it 'incorporates spontaneously' into molecule-sized nanoparticles, important for the kind of highly targeted, combination therapy being developed to treat cancer.
The structure is also simple enough that the scientists can reproduce it.
"ScA is the first, and most potent compound we've identified so far. But we don't yet know how abundant ScA is, or if it's feasible to harvest, so it is important that we have been able to produce this natural product in the lab," Stupack said.