MRD & ctDNA Markers
Minimal residual disease (MRD) testing
Testing for minimal residual disease (MRD) is routine in paediatric leukemia and Cergentis supports multiple leading pediatric hospitals in personalized MRD test development.
TLA uniquely enables detection of gene fusion breakpoint sequences at nucleotide resolution. Since gene fusions in leukemia are known to be cancer-driving, clonal events, these breakpoint sequences are ideal markers for sensitive and quantitative MRD testing with PCR.
Circulating tumor DNA (ctDNA) testing
Solid tumors shed DNA and recent years have seen a surge in interest in the use of ctDNA testing on liquid biopsies as part of cancer diagnosis. The most developed and promising application is the use of ctDNA levels to monitor disease progression after initial surgery and/or therapy. Such tests can further help select patients that require, or do not require, therapy or a change of therapy after resistance to an initial treatment occurs.
For reasons outlined above, breakpoint sequences of driving rearrangements are also ideal targets for personalized ctDNA testing with PCR.
For example, TMPRSS2-ERG fusions are found in approximately 50% of prostate cancers. There is currently no targeted therapy available, and fusion detection is therefore less relevant for diagnostics. However, since TMPRSS2-ERG fusions are known to be cancer-driving, clonal events, using TLA for detection of the breakpoint sequences at nucleotide resolution creates ideal markers for sensitive ctDNA testing with PCR.
Cancers caused by viruses, such as cervical cancers, frequently have unique viral integration sites in the host genome, and breakpoints of these integration sites can serve as monitoring markers.
Other cancers with recurrent SVs, such as colorectal cancer, may also benefit from this strategy.