The research takes into account tiny particles called ‘exosomes’ that are shed by cancer cells into the blood and contain the entire genetic blueprint of cancer cells.
“By decoding this genomic data and looking for deletions and mutations associated with cancer, we believe this discovery could be translated into a test that helps physicians detect cancer and treat patients,” said Raghu Kalluri, chairman and professor in University of Texas’ MD Anderson’s department of cancer biology, reports IANS. “At present, there is no single blood test that can screen for all cancer-related DNA defects,” added Kalluri.
In many cases, current protocols require a tumour sample to determine whether gene mutations and deletions exist and therefore determine whether the tumour itself is cancerous or benign, said the study published in the Journal of Biological Chemistry.
“To procure tumour tissue, one needs to know that a tumour exists and if so, is it accessible for sample collection or removal? Finally, there are always risks and significant costs associated with surgical procedures to acquire tumour tissue,” informed Kalluri.
The MD Anderson research team was surprised to learn that the person’s entire double-stranded genomic DNA spanning all chromosomes can be found in exosomes, including those mutated chromosomes that cause various cancers.
Furthermore, Kalluri and colleagues discovered that DNA derived from exosomes carried the same cancer-related genetic mutations compared to the cancer cells taken from tumour. “We believe analysis of exosome DNA taken from blood samples may not only help determine the presence of a cancerous tumour somewhere in the body but also identify mutations without a need for tumour sample,” added Kalluri.
This would increase our abilities to detect cancer in an earlier stage and therefore increase our chances of effective treatment, he added.