Leading scientists and clinicians at the Akershus University Hospital (Norway) have identified mitochondrial DNA (mtDNA) variants to predict metastatic progression of rectal cancer. High rates of systemic failure after curative-intent therapy in locally advanced rectal cancer (LARC) call for new diagnostic tools to improve risk-based treatment stratification. The actual mtDNA variants were single-base alterations and might thus be analyzed by PCR and developed as a feasible assay for metastatic risk assessment in colorectal cancer.
The scientist discovered that blood mtDNA polymorphisms correlate with the immune system’s control of organ metastasis and thus can be used as diagnostic marker. 41 LARC patients given radiation and surgery had DNA extracted from whole blood sampled at the time of diagnosis, and any metastases were recorded over 24-60 months of follow-up. For each patient, two MT-RNR2 sites were homoplasmic for either the normal or a deletion (3105AC > A, 3106CN > C) variant, categorizing the patients into two groups that comprised the same cases for both mtDNA sites.
Figure 1. Polymorphism of the 3105 site of whole blood mtDNA in 44 high-risk rectal cancer patients. Cases had either the wild-type site (heteroplasmy of 0) or a highly heteroplasmic variant (3105AC>A). Open circles; cases without progression. Closed circles; cases with metastatic progression. The single metastatic case in the high heteroplasmy group appeared in a patient who had declined primary tumor surgery (i.e., refused the full curative-intent therapy).
A provisional patent application protecting the specified tests has been filed. Development plans Validation of the biomarkers in a different cohort is ongoing.
Inven2 AS seeks partners for co-development and/or out-licensing of the technology. We are interested to get in touch with relevant diagnostic companies and to discuss the potential of the technology in different screening programs.