Researchers in Australia have developed a 10-minute test that can detect the presence of cancer cells anywhere in the human body, CNN reports.
The test in the new study was developed after researchers from the University of Queensland found that cancer forms a unique DNA structure when placed in water.
Our research has found that cancer DNA forms a unique structure when placed in water. The structure is the same in DNA from samples of breast, prostate and bowel cancers, as well as lymphoma. We used this discovery to develop a test that can identify the cancerous DNA in less than ten minutes”, wrote lead researcher Professor Matt Trau and his research partners Abu Sina and Laura Carrascosa in an article for academic news site The Conversation.
Gold particles attract cancerous DNA
Current detection of cancer requires a tissue biopsy – a surgical procedure to collect tissue from the patient’s tumour. One possibility, still in development, is a liquid biopsy, testing for circulating cancer DNA in the blood.
The new test also uses circulating cancer DNA but involves a different detection method.
In the lab, gold particles are commonly used to help detect biological molecules (such as DNA). This is because gold can affect molecular behaviour in a way that causes visible colour changes. We discovered that cancerous DNA has a strong affinity towards gold, which means it strongly binds to the gold particles.
This finding directed us to develop a test that can detect cancerous DNA in blood and tissue. This requires a tiny amount of purified DNA to be mixed with some drops of gold particle solution. By simply observing the colour change, it is possible to identify the cancerous DNA with the naked eye within five minutes”, the authors explain.
The test also works for electrochemical detection – when the DNA is attached onto flat gold electrodes. Since cancer DNA has higher affinity to gold, it provides a higher relative electrochemical current signal in comparison to normal DNA. This electrochemical method is highly sensitive and could also eventually be used as a diagnostic tool.
Still not used on humans
The 10-minute test developed in Australia is yet to be used on humans and large clinical trials are needed. But so far the signs are positive. Tests on more than 200 tissue and blood samples detected cancerous cells with 90% accuracy, the researchers said.
The next step for the team is to stage clinical studies into how early cancer can be detected, and whether the test can be used to gauge the effectiveness of treatment.