A newly discovered cellular protein could be used as a unique indicator for prostate cancer. PCa-24 could lead to development of a screening test that clearly distinguishes between prostate cancer and benign prostatic hyperplasia (BPH) before patients undergo a biopsy, according to the results of a study published in Cancer (December 15, 2003). Using proteomics, the researchers were able to pinpoint PCa-24, which is a smaller protein than prostate-specific antigen (PSA).
In the study, PCa-24 was solely detected in 94% of epithelial cells from prostate cancer but was not found in normal prostate cells or in BPH cells. The current method of screening for prostate cancer includes testing levels of PSA. PSA values >4 can necessitate further evaluation with a needle biopsy. Yet, PSA can be produced in high levels by either prostate cancer or BPH. Furthermore, almost 35% of men with prostate cancer have normal PSA values. Therefore, PSA serum level is not a specific marker for prostate cancer and may result in preventable needle biopsies.