GNN - Genome News Network  
  Home | About | Topics
Another use for jellyfish gene
Tracking the spread of cancer
By Roberta Friedman

The first genetically modified monkey, ANDi, was born with a jellyfish gene for a protein that glows. The protein was intended to be a marker indicating the presence of the gene, but ANDi's creators are unable to detect it so far in the monkey. There are some promising experiments involving the jellyfish gene, however. Researchers at a California company, Anticancer Inc, successfully hitched the green fluorescent protein gene to metastatic cancer cells in mice, suggesting a potential strategy for tracking the spread of cancer in humans.

In the experiments, mice received injections of the jellyfish gene for several days after human stomach cancer tumors were implanted in their abdominal cavities. The virus ferrying in the gene successfully delivered the cargo to cancer cells, while normal tissues did not take in the gene. The cancer then spread, its progress highlighted over the next few weeks by the green fluorescence of the affected organs.

If developed for use in humans, the strategy offers a potential tool for detecting recurring cancers in patients after a primary tumor is removed. The mouse work involved making an incision to view the fluorescence under a microscope. Other mice with labeled cancer cells have been imaged while moving around freely in a box illuminated with blue light: The liver, invaded by the cancer, shows as a bright cluster of spots 72 hours after delivery of the gene.

The fluorescence generated by the gene in a whole mouse can be "recorded and processed by essentially garden-variety optical instrumentation," the researchers say in their reports, which appeared in Cancer Gene Therapy, and in Proceedings of the National Academy of Sciences. The approach also offers real-time sensing of gene expression for any gene that can be linked to the green protein gene.

See related GNN article
»Introducing ANDi: The first genetically modified monkey

. . .

Hasegawa, S., et al. In vivo tumor delivery of the green fluorescent protein gene to report future occurrence of metastasis. Cancer Gene Ther 7, 1336-1340 (October 2000).
Yang, M., et al. Visualizing gene expression by whole-body fluorescence imaging. Proc Natl Acad Sci U S A 97, 12278-12282 (October 24, 2000).

Back to GNN Home Page