CHICAGO -- A team of researchers at Purdue University has found a protein in the blood that may prove to be more reliable than the standard prostate specific antigen (PSA) test in measuring the extent of prostate cancer.
According to D. James Morre, Ph.D., distinguished professor of medicinal chemistry at Purdue, the protein -- called tNOX -- is a member of a family of proteins that are involved in cell growth. Normal cells express the NOX enzyme only when they are dividing in response to growth hormone signals. In contrast, cancer cells have gained the ability to express NOX activity at all times. This overactive form of NOX, known as tNOX for tumor-associated NOX has long been assumed to be vital for the growth of cancer cells, because drugs that inhibit tNOX activity also block tumor cell growth in culture.
Morre's group -- in collaboration with colleagues at NOX Technologies in West Lafayette, Indiana, and Marshall Edwards Inc. in New York -- wanted to determine if the tNOX protein could be used to monitor disease progression in prostate cancer. That is, could tNOX serve as a biomarker for not only detecting the cancer, but also in gauging the amount of disease.
Results were presented at the first meeting on Molecular Diagnostics in Cancer Therapeutic Development, organized by the American Association for Cancer Research.
Prostate cancer can be difficult to detect and track because of inaccuracies in current testing methods. The PSA test gives false-positive readings at least 20 percent of the time, resulting in unnecessary biopsies to confirm disease. The digital rectal exam in which a doctor physically checks the prostate is also plagued with reliability problems. At the same time, relying on changes in PSA levels to correlate with disease progression whether with treatment or not can be problematic.
In the study, Morre's group collaborated with Marshall Edwards Inc., which was conducting a phase II clinical tr
Contact: Warren Froelich
American Association for Cancer Research