Acromegaly drug shown to stop cancer growth

A growth hormone inhibitor, discovered by John Kopchick, Ph.D., may treat certain cancers

By Anita Martin

Photo by Josh Armstrong

A drug developed by an OU-COM faculty member has the potential to treat cancer of the breast, prostate and colon, as well as some brain cancers.

In 1989, a team of researchers led by John Kopchick, Ph.D., Goll-Ohio Eminent Scholar and professor of molecular and cellular biology, found a compound that inhibits growth hormone (GH) action. They discovered that it could treat acromegaly, a chronic disease that causes swelling of facial features and/or internal organs, and they also suspected its potential to stop, prevent or even reverse the growth of tumors.

The substance, a “growth hormone receptor antagonist” called Pegvisomant, hit pharmacies in 2003, after its FDA approval, in the form of the prescription drug Somavert®, still the most used treatment for acromegaly. But Kopchick and research partners from around the world have continued to study the effects of Pegvisomant on cancer, and the years of work show great promise.

“Several studies have shown that this GH receptor antagonist reduces the progression of breast cancer in mice models – as well as prostate, colorectal and some brain cancers,” Kopchick says. “In some cases, the data shows that (Pegvisomant) even reverses the cancer.”

The cancer-related data sparked by his discovery comes from many different disciplines and around the world. The research can be divided into three approaches:

1.      Trying to induce breast cancer in mice that lack growth hormone. According to Kopchick, the cancer won’t grow without growth hormone.

2.      Giving Pegvisomant to mice with breast and other types of cancers. The growth hormone antagonist stops – and in some cases, reverses – the growth of the tumors.

3.      Giving Pegvisomant to mice hosting human cancer tissues. Again, the antagonist halts the growth of breast and certain brain cancers.

Before Kopchick’s GH antagonist can be applied to cancer treatment, the effects will have to be studied in clinical trials with human patients. According to Kopchick, the overwhelming success of the mouse studies indicates that the study is ripe for that next phase of testing.