In September 2010, British medical researchers unveiled what might be an interesting new breakthrough in breast cancer research: an active ingredient in watercress seems to to block off growth of breast cancer tumours.
Watercress is a Eurasian perennial leafy vegetable. It is currently cultivated for sale, often after being hydroponically grown and particularly for sale in Britain. It is known to be a useful nutrient thanks to contents such as iron, Vitamin A, calcium, Vitamin C (necessary to prevent scurvy, as well as for general health), and folic acid. It also contains iodine, necessary for proper functioning of the thyroid glands.
The new round of research, turned up another unexpected possible benefit. Researchers at the University of Southampton in Britain, working under Graham Packham, were doing molecular research relating to cancer when they discovered that a chemical found in the plant seemed to play a role in preventing breast cancer. The chemical in question, phenylethyl isothiocyanate, can deactivate a protein known as Hypoxia Inducible Factor (HIF), which, left unchecked, helps cancerous tumours grow in the body.
Essentially, what makes abnormal cells malignant, or cancerous, is that they have lost certain genetic imperatives and either fail to die on schedule, or start reproducing excessively. In either case, the result is a growth of cells which should not exist, either because they should have died or because they should not have divided as quickly as they did. The growth continues until it is manually removed by surgery, medically reduced by radiation or drugs (chemotherapy), or until it jeopardizes the survival of the body as a whole. To get to that point, though, the tumour has to start growing new blood vessels to deliver nutrients to the growing population of abnormal cells. The new Southampton research suggests that HIF is necessary to prompt that growth – and that watercress may be able to block it. If it works, that would mean starving tumours at an early stage of development, before they can become life-threatening.
Packham’s research involved giving people who had already survived treatment for breast cancer 80 grams of watercress, equivalent to eating a bowl of the leafy vegetable, and then monitoring their blood levels over the day following the meal. First, his team established that phenylethyl isothiocyanate altered a protein called 4EBP1, which in turn led to switching off the functioning of HIF (the protein some cancers use in building new blood vessel networks). Next, they gave the participants in their study the watercress meals, and confirmed that detectable levels of the chemical showed up in their blood and had an impact on 4EBP1.
The results of this study were published in a pair of articles, one in the British Journal of Nutrition and the other in Biochemical Pharmacology. It is still far too early to tell whether this theoretical discovery will be confirmed to have a meaningful impact on cancer growth, but it is an interesting example of new research into manipulation of cancer at the level of proteins and other chemicals within the blood.