Recent study presented in PLOS Medicine, examined the levels of particular DNA fragments in the blood of ovarian cancer sufferers. The results could finally lead to a blood test that can make correct forecasts about tumor size and disease advancement.
The sooner ovarian cancer is identified, more chances for the treatment to be successful.
High grade serous ovarian cancer (HGSOC) is the most dangerous type of ovarian cancer, accounting for 70 % of cases.
Presently, as with most other cancers, evaluating how well a therapy is performing is challenging. In a perfect world, if physicians had full visibility of how a tumor was reacting to a specific medication, they would be capable to manipulate the drug type and schedule with more confidence.
Treatment and development of HGSOC are measured by gauging levels of a protein known as CA-125. However, following one or two treatment cycles, the levels do not modify quickly sufficient. This makes outcomes difficult to understand. Also, CA-125 can be indicated by normal tissue, making incorrect readings a further concern.
Finding an ovarian cancer biomarker:
Investigators from Cancer Research UK’s Cambridge Institute recently determined to examine another molecule that might act as a more responsive marker. A team of researchers, led by Nitzan Rosenfeld and James Brenton.
The molecule in question is circulating tumor DNA (ct DNA). These short sections of genetic code are produced from tumor cells as they die. They get into circulation and can be picked up in the bloodstream.
Ct DNA has been examined for more than 2 decades, but making use of it as a diagnostic tool has not been simple – very small portions of ct DNA must be recognized within a sea of normal circulating DNA fragments.
Thanks to latest advances in the sensitivity of assaying technology, ct DNA has turn out to be a possibly useful tool for evaluating cancer progression. However, while there have been a variety of fascinating studies indicating ct DNA’s possible use in tracking cancer, study is still in its infancy.
To examine these fragments even more, Rosenfeld and Brenton focused particularly on levels of ct DNA that carried mutations in the gene TP53. These mutations can be identified in 99 % of sufferers with HGSOC.
The study team had taken 318 blood samples from 40 HGSOC sufferers before, during, and after treatment. Together with these analyses, computerized tomography (CT) scans of tumors and data on the advancement of the cancer were also recorded.
The team identified that levels of mutated TP53 in ct DNA (TP53MAF) associated with the volume of the tumor (when compared with the CT scan), and also the sufferer’s time to progression.
When compared with the diagnostic capabilities of CA-125, TP53MAF fared much better. CA-125 had taken 84 days to reflect modifications following chemotherapy. TP53MAF, on the other hand, took just 37 days.
TP53MAF outcome forecast
In sufferers being treated for a relapse, a cut down of 60 % or less in TP53MAF was related with a weaker reaction to chemotherapy and a time to advancement of under 6 months. A reduce in levels of more than 60 % was connected with a longer time to progression.
In simple terms, a higher drop in the amount of tumor DNA identified in the blood correlates with enhanced patient outcomes.
Commenting on their research authors said,
“These results have strong possibilities for clinical utility owing to the ease of assaying DNA in plasma and the reduced cost and speed of ct DNA testing. Getting very early information on reaction would enable patients and doctors to test alternative therapy choices and have high utility in trials that connect biomarkers to targeted therapy.”