Supernutrition vs. cancer - the best offense is a good defense

Better Nutrition, March, 1997 by Stephen Langer, James J. Gormley

Is cancer winning? No way around it: cancer is winning the war against us. Or is it? One would be inclined to think so after looking at the statistics. Between 1973 and 1992, the overall cancer death rate rose by 6.3 percent. Blacks and people over 65 have fared even worse: in both groups, the overall death rate escalated by about 16 percent.

The statistics

In the last year, it was predicted that 555,000 U.S. cancer patients would die -- up from 331,000 deaths in 1970. It is said that some 40 percent of Americans will get a form of the disease, and that more than one in five will die of it. On a global scale, the World Health Organization estimates that cancer kills nearly 6 million people each year.

Some important strides

On the other hand, there have been some real successes. There have been remarkable reductions in death from certain cancers, especially Hodgkin's disease, Burkitt's lymphoma, testicular cancer, specific cancers of the bones and muscles, and a number of malignancies that hit children. In fact, the American Cancer Society has reported that, since 1960, the cancer death rates in children have dropped 62 percent.

Due to improved (and earlier) detection and revised treatment approaches, there have also been some reductions in the mortality rates of breast cancer (down 5 percent between 1989 and 1993) and colorectal cancer (down 17 percent between 1973 and 1992).

Prevention is key, but politics is holding it

As John Rennie and Ricki Rusting wrote in Scientific American in September 1996, "Prevention is still an idea with plenty of untapped potential."

By some estimates, if the government and individuals did more to reduce risky lifestyle habits, upwards of 200,000 lives could be saved from cancer each year, even if no new treatments were discovered.

Additional lives should also be saved as a result of a treasure-trove of fundamental findings from basic research (scientific as opposed to clinical) over the past 20 years about how cancer develops and progresses, explain Rennie and Rusting.

Sadly, politics and economics -- or should we say the economics left after the politics is finished with it -- stand in the way of accomplishing more to prevent cancer. U.S. government funding for cancer research stood at $2 billion in 1996, which barely keeps up with inflation.

In an editorial by Donald S. Coffey that appeared in the journal, Cancer, "Total federal research funding per year for the two leading cancers diagnosed in the U.S. (male prostate and lung) would not represent enough to purchase three new fighter planes."

The physiology of cancer

What is cancer? The term "cancer" refers to over 100 types of the disease. While nearly every tissue in the body can give rise to malignancies, some can yield several forms.

The 30 trillion cells of the normal, health body exist in a complex, interdependent matrix. Normal cells only reproduce when instructed to do so by other cells in their locale. This almost neurotic collaboration ensures that each bodily tissue maintains dimensions and architecture appropriate to the body's requirements.

Cancer cells violate the rules. They ignore the usual controls on proliferation and follow their own internal scheme for reproduction. As Rennie and Rusting put it, "They [cancer cells] also possess an even more insidious property -- the ability to migrate from the site where they began, invading nearby tissues and forming masses at different sites in the body [...] They become lethal when they disrupt the tissues and organs needed for the survival of the organism as a whole."

What we've learned over the last 20 years

We now realize that tumor cells descend from a common ancestral cell that at a given point in time -- usually decades before a tumor can be felt -- brings into play inappropriate reproduction. In addition, the malignant metamorphosis of a cell happens through the build-up of mutations in specific classes of the genes within it.

Two gene classes are critical in triggering cancer -- proto-oncogenes, which encourage cell-replication, and tumor suppressor genes, which inhibit it. Cancer cells often start reproducing like crazy because genetic mutations cause stimulatory pathways to issue too many "go" cues or because inhibitory, modulating pathways can no longer communicate "stop" signals.

Also critical is the cell cycle clock which -- made up of an assembly line of interacting proteins in the nucleus -- normally integrates signals from the inhibitory and stimulatory pathways and, if the stimulatory commands win out, programs a cell's move to division. This progression is now known to involve increasing levels of proteins, called cycling: first the D type, then E, A, and B.

Invasion and metastasis are the processes that can spread cancer cells throughout the body. It is the process of cellular adhesion that allows cancer cells to wedge themselves into a group of normal cells (cell-cell adhesion) and to plant themselves on top of a grouping/extracellular matrix of other cells (adhesion to the extracellular matrix).