Researchers from The University of Bradford in the UK have developed a new blood test which utilises the damaging properties of UVA (Ultraviolet) light to potentially detect all types of cancer.
Early diagnosis is more difficult in certain types of cancer such as melanoma, colon cancer and lung cancer; consequently lowering the survival rates. This is usually because the symptoms themselves do not clearly show until the later stages of the disease, meaning that treatment is more often complicated and intense than if there had been a diagnosis earlier on. The new blood test could therefore prove to be an invaluable diagnostic tool if the future trials prove to be as accurate as these early results.
The test itself is called the Lymphocyte Genome Sensitivity (LGS) test and works via the analysis of white blood cell DNA damage upon exposure to UVA light.
“White blood cells are part of the body’s natural defence system,” said Professor Diana Anderson, lead researcher in the study.
“We know that they are under stress when they are fighting cancer or other diseases, so I wondered whether anything measurable could be seen if we put them under further stress with UVA light. We found that people with cancer have DNA which is more easily damaged by ultraviolet light than other people, so the test shows the sensitivity to damage of all the DNA – the genome – in a cell.”
The damage done to the DNA is analysed using an electric field, where the DNA is pulled from the negative end towards the positive end in a process called gel electrophoresis. DNA is negatively charged due to phosphate ions in the ribose-phosphate backbone of the molecule and so resists the positive charge. The extent of the damage to the DNA is shown by the ‘tail’ left along the gel. The longer the tail, the more damage was done to the DNA and the larger the likelihood of a pre-cancerous or cancerous condition.
Professor Anderson said, “Whilst the numbers of people we tested are, in epidemiological terms, quite small, in molecular epidemiological terms, the results are powerful. We’ve identified significant differences between the healthy volunteers, suspected cancer patients and confirmed cancer patients of mixed ages at a statistically significant level of P<0.001.”
There are further trials being conducted at the University to examine the LGS test’s accuracy at determining which patients with suspected colorectal cancer require a colonoscopy and which don’t.
To read the full paper, published in the Journal of the Federation of American societies for Experimental Biology, click [here]