This one's for you, Dr. Witherspoon

Posting's been light the last few days, as I do a major housecleaning and organization before I leave for Philadelphia in July. But this turned up at the bottom of a stack of papers, and as it's on the subject of my last post on teachers, I'll take a break to post it to my blog.

This was the introduction to a paper on apoptosis that I wrote for an assignment in one of my first informatics classes, "Biology for Informaticists" in Fall 2000. One of the aspects of informatics that I am very interested in researching is how we organize information. As apoptosis was a brand-new topic to me at the time, I began gathering information, and found that the differences between apoptosis and necrosis reminded me of a distinction I had seen drawn elsewhere, but in a very different context.

Raven's Apoptosis Paper: Introduction

When I began research for this paper, I did not really know anything about apoptosis, except that it was some kind of cellular suicide, and that it was a popular buzzword among people interested in cancer.

While the word α π ο π τ ω σ ι ς (from the root "to drop, to fall" [of leaves]) in the senses of bone dislocation or erosion, or of shedding of scabs, dates back to the writings of Hippocrates of Cos and of Galen (Mauro Dello Esposti, "Apoptosis and the Classics"), and "programmed cell death" at least back to the 1960s, the modern sense of apoptosis can be traced to the publication in 1972 in the British Cancer Journal of a seminal article by J.F.R. Kerr, A.H. Wyllie, and A.R. Currie. From that initial publication, the MEDLINE citations at last count have grown to 38870 items over the last 28 years. The size of that number--obviously prohibitive for researching thoroughly for this paper on the face of it--speaks simultaneously to the intense research interest in the topic, as well as to the need to develop a practical strategy to approach the body of literature in any meaningful way.

Although I did not yet have a conscious organizing strategy when I set out, the more I read and studied about apoptosis, the more I was stuck by the parallels among the cellular physiological processes taking place, and the events described in the Navajo origin story, Diné Bahane'[1]:

...For the Navajo, death of old age is considered to be both natural and highly desirable.

In Navajo mythology, Coyote, the philosopher, argued that death had to be a part of the scheme of this world. He argued that if death did not occur, the earth would soon be overcrowded, and there would be no more room for corn fields. He concluded that it was better for each person to live a limited time, and then leave and make room for the children. The people recognized the wisdom of his words, and agreed that it would be so. (Reichard, 1950a:42).

Birth and death are recognized as structural opposites; one cannot exist without the other. This is manifested in mythology when Monster Slayer, who is in the process of killing the enemies of the people, comes across Old Age with the intention of killing him.

Directly, Old Age spoke up, "In spite of all, I am going to live on, my grandchild," he said... "You have not the right thing in mind, I see," he told him. "Should you kill me, dying would cease," he said. "Then too giving birth would cease," he said, "and this present number of people would continue in the same amount for all time to come. While if I live on, old age will do killing and giving birth will go on in the future. As giving birth goes ahead, so deaths will go on in the other way," he said. "The various birth beings, all without exception, should continue to give birth in the future, every kind of moving being, none excepted," he said.

"Now think this over, my grandchile, you can see now how this thing is!" he told him (Wyman, 1970:573).

Life is considered to be a cycle which reaches its natural conclusion in death of old age, and is renewed in each birth. Death before old age is considered to be unnatural and tragic, preventing the natural completion of the life cycle. Whereas illness usually comes from various forms of disorder and disharmony, premature death usually results from malevolent intentions and deeds[2].

Hinted at in that description of events are analogies to the concepts explored in this paper of:

• apoptosis vs. necrosis as different mechanisms of cellular death: a peaceful, good death determined internally in the fullness of one's own time, as ultimately desirable, and as opposed to a premature, violent death at the hands of external forces such as accident, witchcraft, malevolent intentions and deeds, etc.
  
  
• the effects of each kind of cellular death on its immediate environment of its neighbors and the macro-organism at large: violent or premature death leaves ch’ỉįdii--angry, malevolent spirits who wreak havoc on the living, while a peaceful, fulfilled death of old age leaves behind no such ch’ỉįdii
  
  
• apoptosis as autodestruction
  
  
• the parallelism between apoptosis and mitosis at the cellular level
  
  
• the role of apoptosis in developmental embryology
  
  
• homeostasis
  

Obviously, it is possible to take any analogy way too far, and you have to be fastidiously careful not to distort the facts in order to wring a little more mileage out of the analogy. Certainly I am not arguing that the Navajo were actually observing and reporting processes at the granularity of cellular and genetic mechanisms--rather, I am simply suggesting that learning more about apoptosis opens the door to broader, more universal philosophical questions of the type that have been concerning people for millenia: questions on the nature of birth and its relationship to illness, old age, and death, the dynamic tension between individualism and interdependency, etc. It is this fundamental relevance of apoptosis to all of these processes which makes it such an important concept, especially--but certainly not solely--in research on the mechanisms of cancer, and its prevention and treatment.

I am not going to deal with these questions and paradoxes at the broader level any further in this paper--from here on, the focus will be on the cellular physiology level--but I just wanted to mention that the framework outlined in this creation story provided very useful conceptual hooks for me to approach what was initially a huge and confusing body of literature, and enabled me to begin to sort out and make some kind of sense of it.

[1] Much later, I discovered that I was by no means the first to draw such analogies between apoptosis in the cellular and the social organisms--the word "apoptosis", in the social and political sense, dates back at least as far as the writings of Marcus Aurelius--whose physician was Galen! (Dello Esposti, 1998)

[2] Witherspoon, Gary. Language and Art in the Navajo Universe, University of Michigan Press, 1977: pp. 19-20.