Originally created 05/05/98

Compounds combine to kill cancer tumors



The discovery of two compounds that can kill cancerous tumors in mice sent Wall Street into a frenzy Monday but was greeted with cautious optimism among researchers and cancer survivors in Augusta.

"It is very exciting work," said Dr. Russell Burgess, chief of hematology/oncology at Medical College of Georgia. "Is it going to be the magic bullet? I don't see that happening. I've been hearing that for too long now. (But) I do think there is something there."

Dr. Judah Folkman of Harvard University is using two compounds called angiostatin and endostatin, which are potent anti-angiogenesis agents.

"Tumors need a blood supply in order to grow. They need a blood supply to give them nutrients," Dr. Burgess said. "Anti-angiogenesis inhibits the growth of blood vessels. If growth is limited, the tumor is cut off, and the tumor dies."

Cancerous tumor cells secrete a factor that stimulates blood vessel growth, and the drugs being studied give the surrounding cells an oversupply of that factor, which triggers a feedback mechanism that actually shuts off growth, Dr. Burgess said.

The mechanism has been known for a few years, and there are a number of different agents being studied, including the drug Thalidomide, which was banned in the United States after it was linked to birth defects in the 1960s, Dr. Burgess said.

The National Cancer Institute issued a statement Monday saying it is encouraged by Dr. Folkman's results and is working with the companies involved in producing the drugs -- Entremed Inc. and Bristol-Myers Squibb Co. -- to make sure there is enough produced for clinical trials possibly beginning next year.

The news caused Entremed's stock price to nearly quadruple Monday.

The drugs, however, still face a significant hurdle in reproducing the results in humans because the drugs last much longer in mice, and the tumors grow more slowly in humans, Dr. Burgess said.

"It's a big step," he said.

No matter how exciting, news of this sort is always viewed a little skeptically by cancer survivors like Wanda Attaway and Jaudon Piper.

"It would be a wonderful thing to happen. It sounds too good to be true," said Mrs. Piper, 75, who has survived two bouts with breast cancer.

"You don't believe it, not at first," said Mrs. Attaway, 45, who was treated for breast cancer last summer. She is now taking the drug tamoxifen, also recently hailed for its work in preventing breast cancer growth, and she is starting to believe in it.

"I went (Monday) for my checkup and all my scans, and I'm fine," she said.

One of the promising things about the new approach is that it is much more specific in targeting the cancer than standard chemotherapy, Dr. Burgess said.

"You get less side effects," he said.

And that's the best news of all for Mrs. Attaway.

"That would be great because that stuff is awful," she said of chemotherapy.