mtDNA deletion: New biomarker for identifying malignant prostate cancer

Mitomics, world leader in the research and development of mitochondrial genome-based products to improve clinical insight and therapeutic decisions, today announced the publication of new research in the Canadian Urological Association Journal (CUAJ) showing that large-scale deletions in mitochondrial DNA (mtDNA) can indicate cellular changes that are associated with the development of cancer. Importantly, these changes and mutations accumulate in a way that enables quantitative measurement and the diagnosis of disease in adjacent, normal tissue or tumor margins through a "field effect" which may occur in advance of the formation of malignant prostate tissue. These insights suggest a paradigm-shifting approach to diagnosing prostate cancer.

“Utilizing this mtDNA deletion as a biomarker for prostate cancer may provide urologists with a new level of clinical insight by enabling them to confirm true negative biopsies, or potentially detect prostate cancer early and determine the appropriate course of treatment or monitoring for each patient.”

"This publication adds to the growing body of data which demonstrates that detecting this large-scale mtDNA deletion offers a breakthrough approach to cancer detection and may serve as a sensitive predictor of a cancerization 'field effect'," stated Ryan Parr, Ph.D., chief scientific officer, Mitomics, and co-author of the study. "The case studies reported in this article support the significance of this mtDNA deletion as a biomarker for identifying malignant prostate tissues and illustrate the significant potential of our Mitomic Technology™ to address many of the limitations of current prostate cancer detection approaches."

As was discussed in the March 3, 2010 issue of the journal Nature by researchers at Johns Hopkins, the unique structural and functional characteristics of mtDNA make it a highly attractive system for biomarker discovery and disease detection. Large-scale deletions in mtDNA can indicate cellular changes that are associated with the development of cancer. The findings published in CUAJ also suggest that the "field effect" demonstrated by the mitochondrial genome marker may indicate the presence of a small prostate cancer tumor that is difficult to detect through biopsy procedure(s). Researchers found this "field effect" present in normal-appearing prostate tissue in proximity to where a tumor existed, but was undetected through a prostate biopsy procedure.

In the CUAJ study, researchers examined four cases of men who had multiple biopsy procedures due to suspicion of prostate cancer. Three of the men were subsequently diagnosed with prostate cancer. Available negative biopsy samples from the initial procedure were assayed for the frequency of mtDNA deletion as a measure of the prostate cancer field effect. In the cases of men who were later diagnosed with prostate cancer, the frequency of the mtDNA deletion predicted the outcome - 11 months, 21 months and 31 months - prior to a follow-up biopsy procedure. In the benign case, the original mitochondrial DNA deletion score successfully predicted the negative status and confirmed the histology.

"These results published in CUAJ were in-line with findings from our study published in the January 2010 edition of Nature publication Prostate Cancer and Prostatic Diseases in which Prostate Core Mitomic Test analysis of 595 prostate core biopsy samples demonstrated a 91% negative predictive value of the mtDNA deletion for predicting re-biopsy outcomes," commented Robert Poulter, president and chief executive officer of Mitomics. "Utilizing this mtDNA deletion as a biomarker for prostate cancer may provide urologists with a new level of clinical insight by enabling them to confirm true negative biopsies, or potentially detect prostate cancer early and determine the appropriate course of treatment or monitoring for each patient."