Let’s see. Now that I’m back from Chicago, having recently attended a major cancer meeting, not to mention having already blogged about the meeting, what to do next? Sure, the whole thing about Andrew Wakefield finding himself just one step away from appearing on Jeff Rense‘s or Alex Jones‘s radio show was amusing in the extreme to me, and no doubt there will be much more blogging material to mine in that vein, but if you really want to bring home the crazy there’s only one place shy of Whale.to to visit.
That’s right, I’m talking about that wretched hive of medical scum and villainy, Mike Adams’ NaturalNews.com. Now, usually it’s the Grand Master of Woo and Quackery himself, Mike Adams, who really knows how to deliver the crazy quacky goods. Usually. This time, it’s one of Mike’s minions doing the duty, and addressing the nonsense in her post is a perfect post-ASCO thing for a surgical oncologist to do. The minion of woo is S. L. Baker, and the post is entitled Study shows how radiation causes breast cancer.
The first thing you need to remember about NaturalNews.com is that Mike Adams has a deep and abiding hatred of scientific medicine. One manifestation of this hatred is that, when it comes to breast cancer, to Adams surgery, chemotherapy, and radiation kill, not the cancer; “natural” therapies like vitamin D can prevent cancer with near 100% certainty and cure it with near 100% certainty if you happen to be someone who didn’t listen to Adams; and that early detection tests like mammography are always bad, although, ironically enough, a modality that claims to do the same thing as mammography without radiation (thermography, an unvalidated and not particularly useful old technology that, for reasons that I’ve never been able to understand, “alternative” medicine practitioners love) is the greatest thing ever. I’ve written about NaturalNews.com and its hatred of conventional therapy for breast cancer before. For instance, seven months ago, Mike Adams himself mined similar territory that his apparent acolyte has done, while earlier he abused Breast Cancer Awareness month to castigate the “breast cancer industry.” This time around his flunky Baker is doing the castigating:
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 cancer.
Except that mainstream medicine doesn’t dismiss or deny the idea that medical imaging tests can increase the risk of cancer. There are hundreds of articles looking at the risk of cancer due to medical imaging tests. I myself have discussed the issue on no less than two occasions in December last year, once in the aforementioned context of mammographic screening for breast cancer and elevated risk of breast cancer in young women with strong family history of breast cancer or a mutation predisoposing to breast cancer, and once about the concern of the increased risk of cancer due to medical imaging, particularly CT scans. As with everything, it’s a matter of balancing risks and benefits.
After complaining about the material on this website at Cornell, Baker references a study by Paul Yaswen, a cell biologist and breast cancer research specialist with Berkeley Lab’s Life Sciences Division. As is typical for NaturalNews.com, so much so that I strongly suspect it’s intentional, there is no link to the study, an abstract to the study, or even a news story about the study. Actually, I have little doubt that it’s intentional. If Adams or his minions were stupid enough to make it easy for readers to look up the primary sources being abused, it would be too easy for skeptics like me to go to that source and demonstrate the difference between what the scientific study said and the lies that Adams and his ilk tell about it.
Fortunately, it’s Orac that Baker and Adams are dealing with, and it didn’t take me very long to find this Science Daily press release about it from around four weeks ago and this press release from the Lawrence Berkley National Laboratory, which is where the work was done. From these press releases, it was easy to find the actual article by Mukhopadhyay et al describing the results of this work.
The introduction to the abstract reads:
Most human mammary epithelial cells (HMEC) cultured from histologically normal breast tissues enter a senescent state termed stasis after 5 to 20 population doublings. These senescent cells display increased size, contain senescence associated Î²-galactosidase activity, and express cyclin-dependent kinase inhibitor, p16INK4A (CDKN2A; p16). However, HMEC grown in a serum-free medium, spontaneously yield, at low frequency, variant (v) HMEC that are capable of long-term growth and are susceptible to genomic instability. We investigated whether ionizing radiation, which increases breast cancer risk in women, affects the rate of vHMEC outgrowth.
One thing this passage should tell you right away is that the research being described is very basic. It’s also dealing with cells in a dish, not actual human breast cancer. As I always have to point out to my new students an dpostdoctoral fellows, tissue culture is a highly artificial system. Sure, it’s quick, convenient, and frequently useful. However, it’s also sometimes quite misleading. For one thing, cancer cells don’t grow on a plastic dish in what is, essentially, a two-dimensional array. They grow in 3D structures mixed in with other cell types, including fibroblasts, vascular endothelial cells, immune cells, and various other components of the stroma (the tissue admixed with and surrounding the tumor). Another problem is that cells are in essence selected by artificial selection to be able to grow well in cell culture. They are thus often genetically different than cells growing in actual tumors. Over the last couple of decades, there is a growing body of research demonstrating that tumor cells growing in 2D respond differently to growth factors and chemotherapy agents than cells growing in 3D models. It’s one reason why I’ve been striking up a collaboration with a basic scientist who has mastered a 3D culture model of breast cancer. Such a model is closer to “reality,” if you will, than standard tissue culture but at the same time far easier to deal with than implanting tumors in mice as xenografts.
None of this is to say that the research described in this paper is not worthwhile or useful. Rather, it is to be viewed as preliminary. In other words, it requires replication. More importantly, the results of this study should be viewed more as hypothesis generating than anything else. The conclusions need to be confirmed in actual human breast tissue–or at the very least in animal models.
So what did the investigators test? Basically, in normal HMECs grown in serum-free medium, a small number are capable of avoiding senescence. Normal cells in general can only divide a limited number of times. In the case of these particular HMECs, it’s around 5 to 20 times. After that, they stop dividing and enter what is known as a senescent state. Indeed, one of the key differences between cancer cells and normal cells is that cancer cells do not undergo senescence and can continue to replicate indefinitely, a state known as being immortalized. However, a small percentage of normal cells can escape senescence and continue to divide. In this particular system, the cells that escape senescence also develop genomic instability, meaning that they are more prone to developing additional mutations. In the case of HMECs, this loss of senescence appears to be due to the loss of p16, a tumor suppressor gene. Indeed, the mechanisms by which normal cells escape senescence are an area of intensive study, because escaping senescence is so important to carcinogenesis. Since radiation is known to be carcinogenic, the LBNL investigators were interested in whether radiation had an effect on senescence of HMECs harvested from women who underwent reduction mammoplasty (breast reduction) surgery.
To determine what role radiation might have on senescence, the LBNL investigators cultured HMECs and then exposed them to various doses of radiation, comparing them to similarly treated cells that were not radiated. What they found is that after six weeks the vast majority of the cells in both groups stopped dividing. They had become senescent. There were also cells of the vHMEC phenotype (the cells that had escaped senescence). There were the same number of senescent cells in both groups, the number of which didn’t depend on the radiation dose, but in the radiated cells there were larger numbers of vHMEC cells.
The authors then used a computer model to try to figure out what was going on and concluded:
Exposure to sparsely or densely ionizing radiation elicited similar increases in the numbers of vHMEC compared to unirradiated controls. Agent-based modeling indicated that radiation-induced premature senescence of normal HMEC most likely accelerated vHMEC outgrowth through alleviation of spatial constraints. Subsequent experiments using defined co-cultures of vHMEC and senescent cells supported this mechanism.
The idea is thus that radiation induces the premature senescence of normal cells, and that allows space for the vHMEC cells to grow. it’s not an unreasonable conclusion, although I’m always leery when a computer model is used to exaplain a result like that, because any computer model is highly dependent on the input data. It makes me feel a bit better that the LBNL investigators grew HMEC and vHMEC cells to try to validate the prediction of the model, but, again, this model is not the only possible explanation for these results. Another possibility is that perhaps there is a direct effect on vHMEC cells that stimulates their growth and genomic instability. Even so, I have little doubt that in these cells in this system radiation-induced premature senescence has something to do with either allowing or stimulating the growth of vHMECs.
Now back to NaturalNews.com, which concludes:
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 associated with increased incidence of breast cancer (http://www.naturalnews.com/024901.html). And a Johns Hopkins study published in the Journal of the National Cancer Institute concluded radiation exposure from mammograms could trigger malignancies in women at risk for genetic breast cancer (http://www.naturalnews.com/025560_cancer_brst_cancer_mammograms.html).
Of course, results from studies in tissue culture relying on modeling of population growth kinetics, while producing interesting and potentially useful results, should always be considered premature at best. For one thing, cancer is a lot more complicated than that. Cancer is a three-dimensional tissue. It’s also made up of far more than just the cancer cells and normal cells. It’s also made up of fibroblasts, blood vessels, smooth muscle, and immune cells, all in a certain hormonal milieu. Whether radiation does the same sort of thing in a real human breast, who knows? It might. It might not. We know that radiation can induce cancer in the breast; what we don’t know is whether this mechanism is even a significant mechanism, much less The One True Mechanism, which is how it’s being represented in press releases and on NaturalNews.com.
Another thing that is important to know about this study. The dose of radiation used ranged from 0 to 200 cGy, the lowest dose being 5 cGy. The lowest of these doses is around ten times the dose that even an old-fashioned analog mammogram can be expected to deliver to the breast parenchyma, namely 5 mGy. The corresponding author, Dr. Yaswen, puts it this way:
“The work we did was performed with non-lethal but fairly substantial doses of radiation, unlike what a woman would be exposed to during a routine mammogram,” says Yaswen, who is also a member of the Bay Area Breast Cancer and the Environment Research Center. “However, the levels of radiation involved in other procedures, such as CT scans or radiotherapy, do start to approach the levels used in our experiments and could represent sources of concern.”
This is, strictly speaking, true but rather deceptive. For example, a spiral CT scan of the abdomen and pelvis can result in a dose of radiation ranging up to around 30 mGy, or 3 cGy, which is in the same order of magnitude of the lowest dose used in this study. More deceptive still, these doses are doses the whole irradiated area of the body during a CT receives. Let’s assume a woman undergoes a CT scan of the chest, abdomen, and pelvis. Let’s further assume that the dosage received is around 50 mGy, or 5 cGy. Only a fraction of that radiation is going to be received by the breasts; so representing the entire dose of radiation from the CT as going to the breasts doesn’t tell the whole story.
Worse, discussing radiation therapy is way out. A typical radiation therapy protocol for breast cancer provides a total dose of 60 Gy in daily divided doses of around 1.8 to 2 Gy per dose. This is orders of magnitude higher than the highest dose provided to the cells. Moreover, the risks of secondary malignancies from radiation therapy for breast cancer have been studied and well-characterized. How relevant this LBNL model is to the development of these secondary malignancies is an open question. Unwittingly, Dr. Yaswen conflated the issue of radiation from imaging studies and radiation used for therapeutic purposes. In essence, he inadvertently made it easier for Baker and Adams to abuse the results of their research to try to scare women into not getting mammograms. I realize that most scientists don’t even pay attention to loons like Adams and his crew, but I wish more did and were more cautious about their public utterances about their research.
It’s also true that ionizing radiation is ionizing radiation but intent and dosage matter. Using radiation to treat a cancer is different from using it for imaging in that more risk is acceptable. For imaging studies, particularly screening studies, risk is to be avoided using the principle of primum non nocere. What’s also important to remember is that, while Baker and Adams of Natural News try to make it sound as though getting even a single mammogram is deadly, as I pointed out before when I discussed another study looking at mammograms and radiation, if there is an increased risk of breast cancer from mammography it is very small, so small that it’s hard to distinguish from the noise. More importantly, the benefits of screening certainly outweigh the risks for women over 50 and also probably outweigh them for women between 40 and 50.
Mike Adams and his minion S.L. Baker want women to think that breast cancer can be completely prevented by various “natural” supplements and that screening with mammography is so dangerous that no woman should do it. To that end, they will misrepresent and distort any study that they think they can use to serve their message.
Rituparna Mukhopadhyay, Sylvain V Costes, Alexey V Bazarov, William C Hines, Mary Helen Barcellos-Hoff, & Paul Yaswen (2010). Promotion of variant human mammary epithelial cell outgrowth by ionizing radiation: an agent-based model supported by in vitro studies Breast Cancer Research, 12 (1) : 10.1186/bcr2477