Natural Product May Inhibit Tumor Cell Proliferation

Photo: Somocystinamide A (ScA)

ScA causes microvessel death in
zebrafish; © Stoletov/Klemke

The ScA compound was found in the cyanobacteria L. Majuscula, also known as “mermaid’s hair,” gathered off the coast of Fiji in the South Pacific by the laboratory of William Gerwick at Scripps Institution of Oceanography. A diverse team of 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.

“The compound isn’t toxic to the cyanobacteria itself, but activates a ‘death pathway’, present in our cells,” said Dwayne G. Stupack, associate professor of pathology at the Moores UCSD Cancer Center. “When the cells of the blood vessels that feed tumors become activated and proliferate, they become especially sensitive to this agent.”

Gerwick noted that if a normal-sized swimming pool full of cancer cells were treated with ScA, it would take only three milligrams – about the weight of a grain of rice – to kill all of the cancer cells. Wolf Wrasidlo, Ph.D., scientist at the Moores UCSD Cancer Center and author of the work, added 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.

“ScA is the first, and most potent compound we’ve identified so far,” Stupack said, adding that it won’t be the last, as the Scripps team has identified more than 250 unique compounds from L. Majuscula alone. “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.”

MEDICA.de; Source: University of California - San Diego