(This is part one of three articles with excerpts from
“Tumor Angiogenesis as a Target for Dietary Cancer Prevention”
by Dr. William Li.)

Introduction

   Cancer results in over six million deaths each year. In the United States, men have a 43% chance and women have a 38% chance of being diagnosed with any type of cancer during their lifetime.(1)  This makes cancer prevention a top priority to consider!

   However, cancer prevention must be suitable for healthy individuals.  They have to inhibit microscopic tumor growth with minimal adverse effects on healthy tissues.

   It is now well established that tumor growth is dependent upon angiogenesis, the growth of new blood vessels to the cancer.(2-7)  This blood vessel growth to the cancer cells is a critical event.  It is what moves dormant and early stages of cancer to the invasive and malignant growth stages!

   Studies show that the blood vessel growth is directly related to both cancer growth and recurrence.(8-9)  Unfortunately, drugs can’t be prescribed until the disease is diagnosed.  That is why it is so exciting that studies are showing that angiogenesis inhibition nutrients are found in dietary.  We can use these natural inhibitors for achieving cancer prevention.(12-13)

The Body’s AngioGenesis Balance

   All normal cells in the body are located close to a blood capillary so the capillary can deliver oxygen and micronutrients to the cells.(14-15)  This is a nice balanced arrangement because new cell growth is limited by the rate of cells that die (apoptosis).  The limited nutrient supply actually limits new cell growth!

   If the tissue is to grow, it requires angiogenesis (new blood capillaries) to support the increased nutrient demands.(16)

   In normal healthy adults, angiogenesis is suppressed by the body (except for brief bursts during the female reproductive cycle, pregnancy and healing wounds).(17-21)

   There are more than 30 molecules that stimulate blood vessel growth:

(Note:  This list is not essential to readers but important to us for design purposes.)
FGF2 (bFGF)
VEGF – induces: Bcl-2 and receptors,
VEGFR-1, -R2, -R3 and -R4.  (22-26)
PDGF, PlGF, PD-ECGF,
IL-3 – (interleukin-3), IL-8 – (interleukin-8,
TGF? – (transforming growth factor-β),
TNFα – (tumor necrosis factor-alpha,
Neuregulin – a ligand for the ErbB receptor,
KGF or FGF-7 – (keratinocyte growth factor),
   and many more.(27-30)
Elevated levels of bFGF, VEGF, and PD-ECGF
are present in the fluid of cancer patients.(31-32)

   The body balances (pro) angiogenesis regulators (growth) with (anti) angiogenesis regulators so that new blood vessels are normally suppressed.(33)

   Blood vessel growth happens when:

pro-angiogenesis growth factors are increased, or

anti–angiogenesis inhibitors are decreased, (or both). (34-36)

   Growth can be good (as mentioned above) – or bad if the wrong cells are growing!

References

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27. J. Folkman and M. Klagsbrun, “Angiogenic factors,” Science, vol. 235, no. 4787, pp. 442–447, 1987.

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36. K. Ohno-Matsui, I. Morita, J. Tombran-Tink et al., “Novel mechanism for age-related macular degeneration: an equilibrium shift between the angiogenesis factors VEGF and PEDF,” Journal of Cellular Physiology, vol. 189, no. 3, pp. 323–333, 2001.