by S. L. Baker
June 09, 2010
It's well-established that exposure to ionizing radiation can
trigger mutations and other genetic damage and cause normal cells to
become malignant. So it seems amazing how mainstream medicine
frequently dismisses the idea that medical imaging tests from
mammograms to CT scans could play much of a role in causing breast
Take this example from
the web site for Cornell University's Program on Breast Cancer and
Environmental Risk Factors:
In answer to the question "Is ionizing radiation a cause of breast
cancer?", the Cornell experts say,
"Yes" and note "..
female breast tissue is highly susceptible to radiation
effects." But then they pooh-pooh the possible hazard from
mammography x-rays saying the risk …"should not be a factor in
individual decisions to undergo this procedure. The same is true
for most diagnostic x-ray procedures."
If that's not confusing
enough, they turn around and state:
unnecessary radiation exposures should be avoided and continued
vigilance is required to ensure that the benefits associated
with specific procedures outweigh the future risks."
Why radiation causes
Common sense suggests there is plenty of reason to be worried about
radiation causing breast cancer.
And now there's a new
reason to be concerned. Researchers at the U.S. Department of
Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have
discovered that radiation exposure can alter cells' microenvironment
(the environment surrounding cells). And that greatly raises the
odds future cells will become cancerous.
The reason is that signals from a cell's microenvironment, altered
by radiation exposure, can cause a cell's phenotype (made up of all
its biochemical and physical characteristics) to change by
regulating or de-regulating the way a cell uses its genes.
The result can be a cell
that not only becomes pre-cancerous but that passes this
pre-malignant condition on to future cells.
"Our work shows that
radiation can change the microenvironment of breast cells, and
this in turn can allow the growth of abnormal cells with a
long-lived phenotype that have a much greater potential to be
cancerous," Paul Yaswen, a cell biologist and breast cancer
research specialist with Berkeley Lab's Life Sciences Division,
said in a statement to the press.
"Many in the cancer research community, especially
radiobiologists, have been slow to acknowledge and incorporate
in their work the idea that cells in human tissues are not
independent entities, but are highly communicative with each
other and with their microenvironment," he added.
For their study, Yaswen
and his research teams used human mammary epithelial cells (HMECs),
the cells that line breast ducts, where most breast cancers start.
When placed in a culture
dish, the vast majority of HMECs display a phenotype that allows
them to divide between five and 20 times until they become what is
known as senescent, or unable to divide.
However, there are also
some variants of these cells which have a phenotype that allows them
to continue dividing for many weeks in culture. Known as a
phenotype, this type of breast cell arises spontaneously and is more
susceptible to malignancy because it lacks a tumor-suppressing
protein dubbed p16.
To find out what radiation exposure does to the cellular environment
and how it could impact the future of cell behavior, the Berkeley
Lab scientists grew sets of HMECs from normal breast tissue in
culture dishes for about a week. Then they zapped each set with a
single treatment of a low-to-moderate dose of radiation and compared
the irradiated cells to sets of breast cells that had not been
The results, just published in the on-line journal Breast Cancer
Research, showed that four to six weeks after the radiation
exposure, the normal breast cancer cells had stopped dividing far
earlier than they would have normally - and this premature cell
senescence had accelerated the outgrowth of vHMECS.
"However, by getting
normal cells to prematurely age and stop dividing, the radiation
exposure created space for epigenetically altered cells that
would otherwise have been filled by normal cells.
words, the radiation promoted the growth of pre-cancerous cells
by making the environment that surrounded the cells more
hospitable to their continued growth," Yaswen explained in the
The researchers pointed
out that the levels of radiation used in their experiments were not
as much as a woman would be exposed to during a single routine
mammogram but were comparable to those a woman could receive during
a CT scans or radiotherapy "and could represent sources of concern."
Of course, women are often pushed to get annual mammograms, raising
their overall radiation exposure through the years. And, as
NaturalNews has reported, previous research has already provided
compelling evidence linking mammography to breast cancer.
For example, a report published in the Journal of the American
Medical Association's Archives of Internal Medicine found that the
start of screening mammography programs throughout Europe has been
increased incidence of breast
And a Johns Hopkins
study published in the Journal of the National Cancer Institute
radiation exposure from mammograms
could trigger malignancies in women at risk for genetic breast
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