See-Through Fish Help Cancer Research 112
Hugh Pickens writes "What is transparent, swims, and helps cure cancer? Caspar the friendly fish — a zebrafish bred with a see-through body to make studying disease processes easier for rapidly changing processes such as cancer, Zebrafish are genetically similar to humans in many ways and serve as good models for human biology and disease. In one experiment, researchers inserted a fluorescent melanoma tumor into the abdominal cavity of the transparent fish and by observing the fish under a microscope, they found that the cancer cells started spreading within five days and could actually see individual cells spreading. "The process by which a tumor goes from being localized to widespread and ultimately fatal is the most vexing problem that oncologists face," says Richard White, a clinical fellow in the Stem Cell Program at Children's Hospital Boston. "We don't know why cancer cells decide to move away from their primary site to other parts in the body." Researchers created the transparent fish, (photo) by mating two existing zebrafish breeds, one that lacked a reflective skin pigment and the other without black pigment. The offspring had only yellow skin pigment, essentially appearing clear."
That's not a transparent fish... (Score:5, Interesting)
They are? (Score:5, Interesting)
Zebrafish International Resource Center (Score:4, Interesting)
He also has a great family and we had dinner at his house a couple weeks ago, Zoltán making a tasty Thai soup. The best part about visiting is that his wife is French and they're always talking in various languages at the dinner table. For some reason when the dog is bad, they always chastise him in German.
More to the point... (Score:2, Interesting)
1.) I think it's safe to say noone contracts cancer by getting injected with a tumor
2.) A melanoma (external skin cancer) would probably never originate inside the abdominal cavity. In other words, by implanting it you have already "metastasized" it.
and most importantly,
3.) It's a fish. It's not a human. It's not even a mammal. It's not even warm blooded. In other words, while its genetic code may not be too different on a DNA level, it's pretty gosh darned different from a human. Are the conclusions about how a human cancer evolves in a fish clinically relevant in humans. More to the point, will a fish's immune system deal with the spreading cells substantially differently than a human system. Given that genes important in embryonic development are often also oncogenes, does a model organism with a radically different developmental program really reflect how cancer operates in a human.
Bottom line: When mice subjected to the same kinds of experiments are treated with drug candidates, those drugs occasionally seem to work brilliantly. The mechanism of action for those candidates in some cases have been worked out, but still virtually none have any effect in humans. So, clearly, cancer does not work the same way in humans and mice. And mice are a whole lot more closely related to us than zebrafish are.