"Discovering that cancerous DNA molecules formed entirely different 3D nanostructures from normal circulating DNA was a breakthrough that has enabled an entirely new approach to detect cancer non-invasively in any tissue type including blood, "Professor Matt Trau said in a statement". The gold particles change color depending on whether or not cancer DNA is present.
Sharing their discovery in the journal Nature Communications, the researchers described numerous tests that confirmed the telltale pattern of methyl groups in breast, prostate and colorectal cancer as well as lymphoma.
It is based on a process known as epigenetics - the attachment of a chemical tag known as a methyl group to DNA.
Healthy cells pattern their DNA with molecules called methyl groups.
"In healthy cells, these methyl groups are spread out across the genome, but the genomes of cancer cells are essentially barren except for intense clusters of methyl groups at very specific locations", said Laura Carrascosa, a professor at the University of Queensland.
Researchers have hunted for years to find a commonality across all cancers, a so-called "silver bullet" that ties them all together. That test identifies the presence of cancer proteins and gene mutations in blood samples. Mr Eccles of Otago University suggested thinking of DNA as beads on a string when visualising how the test works.
Although the test is still in development, it uses a radically new approach to the detection of cancer, which can make screening for cancer a simple procedure.
The test, which is still in its early stages as the team search for a commercial partner, has so far been trialled on 200 tissue samples and has detected cancer with up to 90 per cent accuracy.
Tiny fragments of gold can be used to detect the remains of cancer cells in the body, avoiding the need for a biopsy.
Nowadays, science is very advanced and, although we haven't found a cure for some diseases, it's easier to detect traces of cancer in a patient's body. Patterns of them in cancer cells, the study suggests, stick to gold. Indeed, this test is so convenient and affordable that in the not-too-distant future we could all be carrying around our own personal cancer detector - on our cell phones. But if the technique is further developed, perhaps the most immediate potential application would be monitoring existing cancer patients for disease recurrence, she said.