Posted on 04/28/2003 8:42:11 PM PDT by FairOpinion
Lucky discovery uncovers cancer-proof mouse
22:00 28 April 03
NewScientist.com news service
A cancer-proof mouse, which can survive being injected with any number of cancer cells, has been discovered by US scientists. The discovery of the resistant mouse could pave the way for future gene or drug therapies if the mechanism by which it fights cancer can be understood
Researchers at the Wake Forest University School of Medicine in North Carolina have now bred a colony of 700 cancer-proof mice from the resistant male they stumbled across while doing other experiments.
Doctors have known for many years that in rare cases, cancers can mysteriously clear up of their own accord. But this is the first time such cancer-killing ability has been shown to be genetic.
"The power of this resistance seems to be unlimited," said biochemist Zheng Cui, the study leader. "You can give them many, many tumour cells and the mice get rid of them."
"This is at a preliminary stage, but very promising," adds pathologist Mark Willingham, another member of the team. "Our hope is that, some day, this will have an impact on human cancer."
Seven generations
The scientists discovered the original cancer-proof mouse by luck during experiments in which mice were injected with soft tissue cancers, called sarcomas. Despite repeated injections, one mouse did not develop cancer.
When this mouse bred with a normal mouse, some of their offspring were resistant. And these resistant mice were also able to confer resistance, for at least seven generations. "The resistance appears to be caused by just one gene, or a cluster of closely related genes," Cui told New Scientist.
The cancer-killing ability of the mice was unusually consistent with different types of cancer. "What's surprising is it appears these mice are able to recognise something in common to all cancer cell lines," said Cui. "Usually it's difficult to find a common theme."
Willingham told New Scientist that the cancer cells are killed by the mice in a "somewhat novel" way. The body's usual first line of defence against invaders - white blood cells called T-cells - were not employed. Instead the body's innate immune system, consisting of cells like neutrophils and macrophages, attacked the tumour cells and ruptured them.
Previous mice bred so that their immune systems could beat cancer went on the develop autoimmune diseases, but that did not happen with these mice.
One significant puzzle that remains is how the mice detect the cancer cells in the first place. Cui speculates that some kind of diffusible factor from the tumour may betray the deadly cells.
The top priority, says Willingham, is to identify the mouse gene responsible for the resistance. "Because of the Human Genome Project, we could then look for a correlate gene in humans," he said.
Journal reference: Proceedings of the National Academy of Sciences: (doi/10.1073/pnas.1031601100)
Shaoni Bhattacharya
And his other great one - "Scientists today discovered that human saliva causes cancer - but only when swallowed in small amounts over a long period of time"
Cancer has been not the thorn in the side to most researchers, but the boondoggle for a secure, lifetime career.
We may never hear of this again.
Sounds like he didn't resist very much. ;-)
[This ping list is for the evolution -- not creationism -- side of evolution threads, and sometimes for other science topics. To be added (or dropped), let me know via freepmail.]
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.