May Expand Understanding of Human Cancer HHMI investigator Tian Xu and colleagues have created fruit flies that can be used as a genetic model for studying how some human cancers arise. The scientists believe that their achievement represents the first direct link between human tumor suppressor genes and those found in the fruit fly Drosophila. More broadly, the experiments demonstrate that even though flies and humans are separated by 800 million years of evolution, the insects can provide important new insights into human cancers, says HHMI investigator Tian Xu at Yale University School of Medicine.
Tumor suppressor genes produce proteins that normally stop cell proliferation.
When such genes malfunction, they produce defective proteins that permit cells to proliferate endlessly, producing tumors. Flies with the human LATS1 gene did not show the widespread tumors and early mortality caused by the non-functioning lats gene, suggesting that the two genes have the same function. In addition, Xu and his colleagues uncovered evidence that lats is a new kind of tumor suppressor that blocks a specific stage of cell proliferation. Thus, he said, the finding hints that further explorations into the molecular signaling machinery involving LATS1 may yield insights into little-understood cancers and perhaps lead to new cancer therapies. In another set of experiments, which were described in a second paper in the February 1999 issue of Nature Genetics, Xu's team disrupted the LATS1 gene in mice.