Dual-drug treatment eradicates cancer in mice
May 3, 1998
The treatment works in part by preventing the growth of tumor blood vessels
Web posted at: 9:33 p.m. EDT (0133 GMT)
BETHESDA, Maryland (CNN) -- Researchers at the National
Cancer Institute have used a two-drug treatment to eradicate cancerous tumors in mice.
"These two new (drugs), which block the tumor blood vessels, are incredibly effective at preventing the growth of cancers in mice, and in fact curing mice with even large tumors," said Dr. Richard Klausner, director of the National Cancer Institute.
Researchers said that over a period of several weeks, the tumors eventually disappeared and did not recur. The drugs,
anti-angiogenesis agents known as endostatin and angiostatin, appear to work against all types of cancers, including leukemia.
Human trials are expected to begin by the end of the year, said Beth Andrews, public affairs spokeswoman for Children's Hospital. The trials will be done in coordination with the National Cancer Institute and will contain just 30 patients.
Klausner said that unlike chemotherapy, which can cause unpleasant side effects such as nausea, the endostatin-angiostatin regime appears easier to tolerate. Bleeding and difficulty with wound healing are potential side effects that researchers will be watching for.
"The tumors do not appear to become resistant to these two drugs as they do with chemotherapy," Klausner said.
Experts warn that thus far only mice -- and mice specially bred to develop cancer -- received the drugs. Humans may not react to the drugs the same way the mice did.
Although some scientists say these drugs are the most exciting treatment they've seen, Klausner said those sentiments are premature.
"We do not know whether this will be the cure we're all waiting for, or whether that single cure that we all might fantasize about even exists," Klausner said.
Angiostatin stops the development of blood vessels that tumors need to grow. Endostatin comes from a piece of a protein and seems to be produced by tumors to stop other tumors from developing in the body.
It explains why some people become literally ridden with cancer after a tumor is removed -- once the big tumor is gone, there is nothing to stop other tumors from growing.
Research suggests these drugs may be able to treat cancer as a chronic disease so patients can live longer, healthier lives.
Reuters contributed to this report.