Vitamin D may help to curb breast cancer, say scientists

Sarah Boseley, "Vitamin D may help to curb breast cancer, say
scientists", Guardian, October 17, 2006,
Link: http://www.guardian.co.uk/medicine/s...924059,00.html

Vitamin D - manufactured by the skin in response to sunlight - may have
a role to play in fighting breast cancer, scientists say today.
Researchers from Imperial College, London, have carried out a small but
significant study showing that vitamin D levels in the blood of women
with early breast cancer are higher than in those with advanced
disease. It is possible, they say, that vitamin D actively helps to
curb the progression of the disease.

There is already some evidence that vitamin D - and sunlight - have a
beneficial effect with regard to breast cancer. Countries that are
further north and enjoy fewer hours of sunshine have a higher incidence
of breast cancer and women living in them are at greater risk of dying
from the disease than those in the sunnier southern climes.

Vitamin D is also found in eggs and fatty fish. It has also been shown
that the vitamin can stop cancer cells dividing in laboratory
experiments, which they must do for tumours to grow. Other research has
shown that women with adequate levels of vitamin D in their blood have
a reduced risk of getting the disease.

It is known that vitamin D can boost the activity of certain genes and
dampen down others. One gene that is boosted is p21, which has an
important role in controlling the cell cycle.

The latest study, published in the Journal of Clinical Pathology - the
first to compare vitamin D levels in the blood of women with early and
late stage cancer - may help inspire new treatments for breast cancer,
the researchers say, possibly by raising vitamin D levels.

"This report, while being an observational study, clearly shows that
circulating vitamin D levels are lower in advanced breast cancer as
compared to early breast cancer," said the lead researcher, Carlo
Palmieri, from the department of cancer medicine at Imperial college.
"It lends support to the idea that vitamin D has a role in the
progression of breast cancer.

"The next step in this research is to try and understand the potential
causes and mechanisms underlying these differences and the precise
consequences at a molecular level. We also need to look at the
potential clinical implications of monitoring and maintaining high
circulating vitamin D levels in breast cancer patients."

The study was small - involving blood tests from 279 women, 204 of whom
had early-stage breast cancer while the rest had advanced disease. The
researchers point out that it is also possible that the cancer itself
is responsible for lowering the levels of vitamin D. Further studies
are needed.