Drug Shown To Slow Growth Of Tumors In Mice.(Brief Article)

2001 NOV 21 - (NewsRx.com & NewsRx.net) -- A new experimental drug has been found to slow the growth of prostate cancer tumors in laboratory studies conducted at Cedars-Sinai Medical Center.

The findings, presented at the AACR-NCI-EORTC International Conference in Miami Beach, Florida, may lead to a new way to treat prostate cancer, a disease that strikes about 198,000 men each year.

The drug, called 2C4, is a monoclonal antibody, or protein that enlists the body's immune system to attack foreign invaders, such as viruses or bacteria. Produced by Genentech, Inc., 2C4 targets HER-2/neu, a protein from the HER kinase family, that controls cell growth. When the HER-2/neu protein is expressed on cancer cells, it can stimulate tumor growth and spread.

"Our lab studies show that 2C4 significantly inhibited tumor growth in both hormone dependent prostate cancer, and in that which had become resistant to hormone blocking drugs," said David Agus, MD, research director at the Cedars-Sinai Prostate Cancer Center and senior author of the study. "These laboratory findings have led us to launch the first clinical trial to test the safety and effectiveness of 2C4 in patients with prostate cancer and other forms of the disease."

In the laboratory study, the investigators evaluated the effectiveness of 2C4 both in cell-lines established in culture and in human tumors grown in mice. In both evaluations, the prostate cancer cells were either dependent on the male hormone, testosterone, to grow (androgen-dependent), or were the type that had become resistant to hormone blocking drugs and grew independently of testosterone (androgen-independent). The prostate cancer cells were then subdivided within the androgen-dependent and independent groups as either slow growing or as the more aggressive form of the disease. The investigators found that 2C4 blocked HER kinase activity, resulting in a significant decrease in tumor growth.

"Although testosterone-blocking drugs initially work by causing tumors to shrink, the tumors inevitably return and resist further treatment. Now, we may have found a therapy to treat patients with recurrent prostate cancer or, even better, at the outset of their disease," commented Agus.

To determine whether 2C4 would block HER-2/neu activity, the investigators added the drug to prostate cancer cell lines in culture and ...