Tiny Fish Reveals Cancer Secrets
The transparent zebrafish is a new hero in war on cancer.
Nov. 7, 2007 — -- Scientists have found a way to watch in real time as human cancer cells produce tumors that spread throughout the body of a living organism. It's as though the body has suddenly become transparent, letting researchers watch the entire drama of how cancer spreads. The spread, or metastasis, is what usually kills cancer victims.
The human body isn't transparent, of course, but researchers have come up with a remarkable substitute. The tiny zebra fish has taken center stage in labs around the world because it is very similar genetically to humans, and its skin is so transparent that scientists can watch as dramatic changes take place.
The zebra fish has made it possible for researchers at the University of California, San Diego, School of Medicine, to watch human cancer cells produce tumors that spread throughout the fish. By examining each step along the way they have come up with an important discovery. It takes two proteins, acting together, to allow the cancer cells to pierce through the wall of blood vessels, a critical step in the spread of cancer.
If they, or someone else, can figure out a way to disrupt that process, it might "block the spread of cancer in the body," said lead researcher Richard Klemke, professor of pathology at the university.
Klemke emphasized that such a development may be years away, but he's convinced that he and his colleagues have moved cancer research "one step closer to understanding the process at the very basic level."
Thus, a handful of resourceful scientists, working with a fish that few thought important just a few years ago, are able to see for themselves just what takes place when something goes terribly wrong inside a living organism. It would be better, of course, if they could do that with humans, but the zebra fish is a worthy partner.
Geneticist Mary Ellen Lane of Rice University has been studying this freshwater fish for years. She said that humans and the zebra fish share at least 80 percent of the same genes. It is so similar that we might as well call it cousin.
