Scientists from the University of Cambridge in the UK have devised a way to detect aggressive tumors that are resistant to treatment.
Cancer usually occurs as a result of oxidative stress. Free radical build up damages cells and if the body cannot detoxify or repair the damage it can result in diseases such as cancer. Antioxidants like vitamin C from fresh fruit and vegetables can prevent this damage by mopping up the free radicals. The most aggressive cancers are those which can rapidly divide without oxidative stress.
The vitamin C inside a cell is different from vitamin C in the bloodstream and is converted to its different form by enzymes found within the cell. Other research has shown that resistant cancers can increase the amounts of enzymes involved in the conversion of vitamin C to help them withstand chemotherapy so scientists were able to develop two "labelled" forms of vitamin C to help them detect the tumors that may be resistant to chemotherapy.
Lead researcher Dr Sarah Bohndiek, based at Cancer Research UK’s Cambridge Research Institute, said: “This is the first time we've been able to show that vitamin C can be used as a marker for imaging regions of high levels of oxidative stress in the body. This not only helps identify tumours more likely to be aggressive or resistant to treatment, it could also provide an accurate means of monitoring treatment response.
“Importantly, oxidative stress is also associated with other neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, meaning this technique could also have wider applications. Clinical trials exploring how this new imaging technique can be used in the clinic are already planned for the near future.”
The researchers concluded:
‘In this study, we have demonstrated hyperpolarization of ascorbic acid and dehydroascorbic acid, the reduced and oxidized forms of vitamin C, to relatively high levels. Both compounds have been administered previously in high doses in clinical studies with little or no observed toxicity and were shown here to exhibit sufficiently long T1's to allow observation of their signals in vitro and in vivo. DHA may provide a hyperpolarized probe for clinical imaging of redox status in vivo not only in cancer but in a wide range of pathologies and could enable resolution of the role of vitamin C in both physiological and pharmacological situations.’
Sources:
Cancer Research UK Press Release, 3rd August 2011 - http://info.cancerresearchuk.org/news/archive/pressrelease/2011-08-03-vit-C-imaging
Hyperpolarized [1-13C]-Ascorbic and Dehydroascorbic Acid: Vitamin C as a Probe for Imaging Redox Status in Vivo, Journal of the American Chemical Society, June 21st 2011 - http://pubs.acs.org/doi/full/10.1021/ja2045925
Reviewed August 8, 2011
by Michele Blacksberg R.N.
Edited by Jody Smith