Gene expression changes in prostate tissue surrounding cancer lesions may allow prostate cancer diagnosis

Apr 8 2011

Researchers have found that gene expression changes in prostate tissue surrounding cancer lesions may allow diagnosis of prostate cancer even if no cancer cells are present in biopsy tissue, according to study results published in Cancer Research, a journal of the American Association for Cancer Research.

"We found that a biopsy needle does not need to hit a tumor to detect the presence of tumor," said lead researcher Dan Mercola, M.D., Ph.D., professor of pathology and laboratory medicine at the University of California at Irvine. Co-lead investigator, Michael McClelland, in the same department, compared the strategy to the game Battleship; "We can detect more cancer cases using 12 shots with a biopsy needle than would otherwise be the case because we have made the ships bigger." Professors Mercola and McClelland are co-founders of Proveri Inc. who licensed the technology from The Regents of the University of California.

Over 1 million prostate biopsies are performed in the United States each year, and these diagnostic tests can miss up to 30 percent of clinically significant prostate cancers. "This means that on average each week 5,770 equivocal biopsies or 1,154 daily equivocal biopsies are reported back to urologists from pathologists," stated Waldemar Lernhardt, CEO of Proveri Inc. "There is a huge, unmet worldwide need for an accurate diagnostic assay for prostate cancer, and this is the mission of Proveri Inc."

Following a review of this manuscript, Dr. Christopher J. Kane, Professor of Surgery, Chief of Urology at the University of California at San Diego stated: "A classifier using the 114 different genes was generated then tested on the stroma near 243 tumor samples and the stroma of 121 non-tumor samples showing very high (97%) accuracy for determining if the stroma is 'near' prostate cancer.

"These authors are the first to systematically analyze the expression array changes of the stroma near prostate cancer and generate a 'classifier' or gene expression based test that can classify stroma as from near prostate cancer with very high accuracy," noted Dr. Kane.

"If validated by others, this has potential significant clinical applications.  A patient with an equivocal biopsy or small acinar proliferation, or atypia, could potentially have the presence of cancer confirmed by a positive test on the nearby stroma, thereby saving the patient repeat biopsies," stated Dr. Kane.

Dr. Mercola further stated: "Important other potential uses are determining who needs expedited repeat biopsy and providing patients with new choices such as neo-adjuvant therapy and prevention therapy with drugs like finasteride. Finally the genes of our diagnostic profile are 'early detection biomarkers.'"

Additional validation studies will be required to confirm the findings, and before pathologists and urologists will likely be able to use a diagnosis based on non-tumor tissue for recommending surgery or other radical treatment, according to the researchers.

Proveri Inc. is developing biopsy tissue based diagnostic and prognostic clinical assays for improved prostate cancer management. The Company combines prostate cancer specific biomarkers detectable in tumor surrounding tissue via immunofluorescence, digital imaging and image analysis.