It looks like you're using an Ad Blocker.

Please white-list or disable in your ad-blocking tool.

Thank you.


Some features of ATS will be disabled while you continue to use an ad-blocker.


The ultimate product of Darwinian selection

page: 1

log in


posted on Jun, 16 2012 @ 11:39 PM
Today, quietly inside your body, you may have been granted these qualities of survival on top of your human instincts as you know them.

1. Your growth is completely self-sufficient and autonomous. You've acquired your own control over growing.
2. You are utterly insensitive to anything that stops you from growing to your fullest potential
3. You've evaded your supposedly 'inevitable' death in the life cycle. You will not die.
4. Your ability to procreate is limitless.
5. You have sustainable access to your own supply of survival essentials; fresh oxygen, food, energy.
6. You can migrate to sanctuary - wherever, whenever you want.

Notably, these six qualities are not abstract descriptions of your behaviour as a living organism. Many of the genes and pathways that enable each of these six behaviours have concretely been identified.

The task is to now connect this causal understanding of your deep biology to the quest for its cure.

Because what is surviving in you with more adaptations and relentlessness than you know even in your most desperate bug-out-bag, survivalist moments is cancer.

In 1999, Robert Weinberg and Douglas Hanahan, two caner biologists, attended a conference on cancer biology in Hawaii. Frustrated at the biological characteristics of tumours being described in such multi-complexity, they sought to organize the rules.

…beneath the incredible heterogeneity of cancer were behaviors, genes, and pathways. In January 2000, a few months after their walk to the volcano's mouth [in Hawaii], Weinberg and Hanahan published an article titled "The Hallmarks of Cancer" to summarize these rules.

source: Interview by Siddhartha Mukheerjee with Robert Weinberg, January 2009.

"We discuss...rules that govern the transformation of normal human cells into malignant cancers. We suggest that research over the past decades has revealed a small number of molecular, biochemical, and celular traits - acquired capabilities - shared by most and perhaps all types of human cancer."

source: "The Hallmarks of Cancer," Cell 100, no. 1 (2000). 57-70.

Cancer is often viewed as a modern disease, but I argue that it has been evolving as fast and fiercely as we have as humans to become the prime, unbeatable disease unsolved by the prime species on the planet.

1. Self sufficiency in growth signals: cancer cells acquire an autonomous drive to proliferate - pathological mitosis-by virtue of the activation of oncogenes.
(genes that need to be activated by mutations).

Meaning, like the normal cell, it divides from one to form two (mitosis) but the growth is unregulated. Cancer is a disease that clones itself, because it initially originates from one ancestral cell that can now limitlessly divide, giving rise to limitless descendants. Ad infinitum.

2. Insensitivity to growth-inhibitory (antigrowth) signals: cancer cells inactivate tumor suppressor genes, such as retinoblastoma (Rb), that normally inhibit growth.

Some background here: Alfred Knudson, Caltech trained geneticist, discerned a subtle difference between random and inheriited versions of retinoblastoma (a rare eye cancer). He grouped children with sporadic Rb and with hereditary Rb into different cohorts. For hereditary cause of the cancer, the diagnosis typically happened 2-6months after birth, but the sporadic group's cancer appeared 2-4years after birth. He found that this data fit a simple model: in children with Rb potential already inherited in their genes, only ONE mutation was required for the cancer to emerge. Children who did not inherit the genetic potential of Rb required TWO mutations for cancer to emerge.

"Two classes of genes are apparently critical int he origin of cancers....One class, that of oncogenes, acts by virtue of abnormal or elevated activity. The other class, that of anti-oncogenes [tumor suppressors] is recessive...cancer results when both normal copies of the gene have been mutated or deleted."

Essentially, cancer switches off our own supressor defences.

source: A, Knudson, "The Genetics of Childhood Cancer," Bulletin du Cancer 75, no.1 (1988): 135-38.

3. Evasion of programmed cell death (apoptosis): cancer cells surpress and inactivate genes and pathways that normally enable cells to die.

Regulated cell death involves specific activations of genes and proteins - and cancer does not obey the blueprints.

4. Limitless replication potential: cancer cells activate specific gene pathways that render them immortal even after generations of growth.

Every generation of cancer cells creates a small number of cells that is genetically different from that set of parents. So different in fact that when your immune system attacks or a new chemotherapeutic drug attacks, mutant clone armies resist the attack and expand outwards and onwards. The fittest cancer cells survive.

5. Sustained angiogenesis: cancer cells acquire the capacity to draw out their own supply of blood and blood vessels - tumor angiogenesis.

Genes write or "encode" proteins which then work like switches that say on and off inside your cell, allowing that cell to function and know what to do in its environment. Early (proto) oncogenes and tumor suppressor genes sit at the hubs of signaling pathways where proteins tell the cell what to do (the molecular cascade of protein A affecting protein B which then switches on protein C, which turns off protein E and F, ad infinitum).

Surgeon and scientist Judah Folkman demonstrated in the 1990s (while working at Boston Children's Hospital) that certain activated signals within cancer cells that induce neighbouring blood vessels to grow. A tumor can completely acquire its own blood supply by forcing a network of blood vessels around itself and then growing around them. I almost vomited when I researched this.

source: Judah Folkman, "Angiogenesis," Annual Review of Medicine 57 (2006): 1-18.

tissue invasion and metastasis: cancer cells acquire the capacity to migrate to other organs, invade other tissues and colonize these organs, resulting in the spread throughout the body.

Meta and statis ("beyond + stillness") allows the wide array of individual types of cancers to choose avenues to travel by - most often the blood. Some types of leukaemia (which is essentially "blood cancer") in which, after poisoning the blood with chemo, the cancer actually stealthily hide in the spinal fluids and the brain, where chemo treatment cannot permeate the brain-blood barrier (your body's built in defence against poison). There the cancer lies in wait and remerges fully fledged, not to mention now living in your brain.

Many cancers are nearly curable. Hodgekins lymphoma, which is primarily not malignantly travelling through the body but an operable growth. Certain types of breast cancer cells with receptors for estrogen can be treated hormonally with tamoxifen (originally a birth control). But cancer is so diverse in its methods of survival and we have so many different cells with different functions that become parents to cancer.

It lives like a desperate survivalist; on inventiveness, being territorial and cleverly defensive - it seems to teach us how to survive. It is a parallel species, perhaps more adapted at survival than even we are.
edit on 16-6-2012 by windus because: forgot close quote


log in