A Cure for Cancer? New Anticancer Drugs Living Up to Promise
A look at angiogenesis inhibitors, experimental cancer treatments.
March 10, 2000 (New York) -- When The New York Times ran a front-page
story in May 1998, Harvard professor M. Judah Folkman, MD, and his work with
experimental cancer drugs quickly became the hope of the future.
The new drugs -- called angiogenesis inhibitors -- worked in mice by
blocking the formation of blood vessels like arteries that feed tumors. And the
Angiogenesis is the body's process of making new blood vessels. Cancers need
new blood vessels in order to grow and spread. But drugs that block the
formation of these new blood vessels can cut off the tumors' blood supply -
hopefully killing them.
Without new blood vessels, tumors can't grow past pinhead size, he explains.
And there are certain proteins in humans that naturally prevent angiogenesis,
Folkman tells WebMD.
So Folkman, a professor of pediatric surgery at Harvard Medical School, and
his colleagues essentially cured the mice's cancer.
Now, almost two years later, nearly 20 of these drugs are in human trials
and about five of them are in the final stage of human testing, Folkman said
Tuesday at a lecture at the Columbia University College of Physicians and
Surgeons in New York. These trials compare the results of people taking the new
treatment with results of people taking standard treatments.
And so far, so good, Folkman tells WebMD. In fact, Folkman has shrunk
cancers in humans with one drug called interferon-alpha. In one case, he was
able to shrink a tennis ball-sized jaw tumor in a girl who, if not for the new
drug, would have become disfigured from receiving radiation to her face. The
drug showed similar results for a patient with pelvic cancer and another
patient with hand cancer, Folkman says.
Interferon-alpha shuts off a chemical that stimulates cells that form blood
vessels' walls. If not shut off, the chemical stimulates the cells, causing
them to divide, produce more cells like themselves, and eventually form a new
blood vessel that feeds the tumor. Interferon-alpha stops that process.
Other angiogenesis-inhibiting drugs in the final stage of trial include
Marimastat, Neovastat, AG 3340, and IM 862, he says.
"The angiogenesis inhibitors are now far into clinical trials," he
tells WebMD. "Ten years ago, there weren't any available, and now companies
are learning how to make the drugs and run the studies," he adds.
"In the future, probably sooner than we think, angiogenesis inhibitors,
once approved, will be added to chemotherapy, [radiation therapy], gene
therapy, [and other cancer treatments] -- and then to one another," he
"It's very interesting that the body has a big family of proteins that
have one job -- to turn off blood vessel growth," he says. "We are
discovering these proteins and, at a very rapid rate, turning them into
Folkman says, researchers have identified eight such proteins that naturally
act as angiogenesis inhibitors. Since they occur naturally in the body, they
are also most likely safe and nontoxic, he says.
- Angiogenesis inhibitors are a group of experimental cancer drugs that block
the formation of blood vessels that feed tumors, essentially starving them and
usually shrinking them down to the size of a pinhead.
- People naturally make many proteins that are capable of blocking
angiogenesis, and researchers are trying to harness the power of these proteins
into effective medications.
- In the future, angiogenesis inhibitors will probably be used in conjunction
with other cancer-fighting regimes, including chemotherapy, radiation therapy,
and gene therapy.