For nearly 20 years, divers searched in deep and shallow water. They
scoured wide ocean swaths. But their prize — a gray, rocklike sponge —
remained elusive. Until now.
In October a team from Harbor Branch Biomedical Marine Research, based
in Fort Pierce, Fla., finally zeroed in on the sponge's hideout while on
a research cruise in the Bahamas.
"We were really excited," recalled Amy Wright, director of the group. "I was just dancing around."
By carefully plotting out every feature of landscapes where bits of the
sponge had been found before, Wright and her colleagues came up with a
likely hideout. Sure enough, they found healthy populations of the
sponge at a depth of 1,000 feet in an area known as the Dead Zone.
Why so much to-do about a little sponge? Researchers believe the
yet-unnamed species holds medical potential and could, quite literally,
save lives.
Endless Finds, Easy to Lose
When bits of the sponge were first found in 1984, preliminary tests
showed a chemical within it was about 400 times more potent than the
drug currently used to treat breast cancer, Taxol. The initial tests
were so promising that lab workers went ahead to see if the chemical
would work to kill cancer cells injected into mice.
Those results were also promising. Then they ran out of sponge.
Running out of supplies of a potential marine medicine is a common problem for those searching for cures in the ocean.
Since the ocean covers 70 percent of the Earth's surface and remains
largely unexplored, scientists believe it may hold many more cures.
Right now about 16 compounds derived from marine species are in clinical
trials. Most of these drugs are for treating different forms of cancer
since cancer foundations have funded ocean exploration for biomedical
research.
But the vastness of the ocean is also its drawback — since species can
quickly be lost in its waters. That's why Wright devised a hunt for the
gray sponge.
"I got a pattern for a depth range and for the kinds of terrain when we found it before," she said.
Now that researchers have replenished their supply (their submersible
vessel yanked 1,200 grams of the sponge from the rocky area of the ocean
floor), Wright is hopeful a new, highly effective pancreatic cancer
drug will emerge within 10 years or possibly only three or four.
"We already know it's going to work in animal models," she said. "So we know it should eventually work in people."
Long Haul
Others take a more cautious view.
"We are always optimistic that this type of early testing will lead to a
new drug," said William Fenical, director of the Center for Marine
Biotechnology and Biomedicine at Scripps Institution in La Jolla, Calif.
"Unfortunately, it rarely does."
Still, Fenical points out, there are rare successes. In fact, his lab has produced at least two of them.
Fenical focuses mostly on microbes that live in the muck of ocean
bottoms and on ship's sides. One such creature, a brown invertebrate
with stringy tufts called Bugula, produces a chemical that is now in
phase 2 clinical trials as a treatment for everything from leukemia to
kidney cancer.
"The phase 2 clinical trial is when the rubber hits the road and
patients who have no recourses try the drug," explained Fenical.
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