■ site map
June 2010 - December 2013
I - Breast cancer risk factors
8. Breast cancer initiating factors
Unlike breast cancer predisposing and promoting factors, which are many and of great variety, there are only a few factors - no more than three - actually initiating cancerous transformation in woman's breast:
1-radiation - primarily ionizing, although non-ionizing radiation shouldn't be entirely discounted -
2-chemical carcinogens, and
In addition to radiation, chemical exposure and viral tumor proteins, DNA alterations resulting in cancerous growth can also be caused by accumulated errors in DNA replication during mitosis. As with other changes in the structure of the DNA molecule, it typically requires the combined effect of multiple alterations to initiate malignant transformation. At present, it is not known how significant are they in breast cancer, but these replication errors are certainly contributing factor to the possible malignant transformation.
In general, the higher rate of cellular proliferation, the more significant it is.
Just like any other complex body function, the quality of DNA replication depends on a multitude of factors, from inheritance and lifestyle to nutritional status and toxic exposures.
There is convincing evidence that radiation exposure is the primary breast cancer causative factor. DNA damage by carcinogenic chemicals is the second, and DNA alterations due to viral infections are yet another, probably the least significant factor.
How harmful these three direct causative factors will be in every individual case, what form the ensuing breast cancer will take, and how it will progress, depends on a variety of predisposing and promoting factors present, in a different form, in every individual case. In general, if the cellular function is already compromised by multiple factors negatively affecting cellular homeostasis and repair, including:
● unfavorably altered gene expression,
● inherited negative genetic polymorphism, compromising cell cycle integrity
● significant oxidative exposure, particularly of the DNA molecule
● nutritional deficiencies and imbalances, negatively affecting DNA repair
● toxic overload, damaging the body and bodily functions
will be more prone to undergo transformation into malignant growth.
All these factors overlap in many ways. For instance, poor (and that does not imply lack of food), unbalanced diet is very likely to compromise body's oxidative and detox protection and could, in fact, negatively alter gene expression. This, in turn, could combine with the inherent genetic polymorphism and result in a further, critical worsening of the cellular repair mechanism and degradation of cell cycle control.
Once a cell turns cancerous, and starts multiplying, how fast it will progress depends significantly on the presence and activity of a variety of factors promoting cellular proliferation, including:
◊ level and balance of ovarian hormones, either endogenous (which can also be affected by stress hormones metabolism) or of external origin (medical treatments, xenoestrogens),
◊ elevated insulin and/or IGF,
◊ low melatonin,
◊ breast compression (wearing bra),
◊ obesity/ weight gain for postmenopausal or lean (undernourished) body for premenopausal women, and
◊ medical hormonal treatments,
as well as on the presence and efficiency of the factors inhibiting their activity or, in general, controlling cellular proliferation.
This is, of course, far from the complete picture, and mainly listing the factors that happened to have relatively significant statistical association with breast cancer incidence and proliferation in most of the studies. What the studies typically do not address is more important:
ü quality of the diet - and not just general quality, but individually-tailored quality meaning that it provides what the individual body specifically needs -
ü toxic load, damaging and obstructing body functions needed for wellbeing in general, and for fighting breast (or any other) cancer in particular,
ü progress in reducing that toxic load and, of course,
ü the state of mind: psychological and emotional wellbeing
Let's take a closer look at radiation, the major breast cancer causative factor.