Compugen Ltd. (NASDAQ: CGEN) announced today the discovery of two novel prostate-specific proteins. These proteins are encoded by alternative mRNA splice variants of the genes for prostate specific antigen (PSA) and its related protein. The novel transcripts were predicted using Compugen's proprietary LEADS computational biology platform and then verified in Compugen¿s molecular biology laboratory. These novel proteins may have important applications in developing additional diagnostic tools for prostate cancer and for understanding the pathobiology of the disease. The discovery is now published in The Journal of Biological Chemistry .

Compugen's LEADS platform, a biologically verified system, is used to create a comprehensive view of predicted genes, mRNA transcripts, splice variants, proteins and detailed functional annotation. LEADS accurately models complex biological phenomena, such as alternative splicing, utilizing advanced computational tools. The platform provides Compugen and its customers with solutions for biological challenges with the goal of accelerating the development of therapeutic and diagnostic products.

Prostate specific antigen (PSA) is the premier tumor marker for screening, diagnosis, monitoring and prognosis of prostate cancer. PSA and human kallikrein 2 are closely related products of human kallikrein genes KLK3 and KLK2 respectively. Both proteins are secreted in the prostate and play important roles as biomarkers in the diagnosis of prostate cancer. Further, there are indications that these proteins might be useful for the diagnosis and prognosis of breast cancer.

In the paper being published in The Journal of Biological Chemistry, Compugen's scientists report the identification of unusual mRNA splice variants of the KLK2 and KLK3 genes. The novel proteins encoded by these transcripts bear no similarity to the kallikrein protein family or other known proteins. Despite the substantial experimental research on the PSA protein and gene, the variant molecules had not been discovered previously.

Compugen CEO Mor Amitai stated, "This discovery reinforces our assertion that Compugen's computational biology research can result in the rapid discovery of possible drug targets and diagnostic markers that would be otherwise extremely difficult to discover experimentally."

Prostate cancer is one of the most common forms of cancer in men and is the second leading cause of cancer death in men. The American Cancer Society and the American Urological Association recommend that men over age 50 have yearly PSA screening tests. The current annual PSA U.S. test market is estimated at $250 million, and the worldwide PSA test market is approximately $500 million.