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If you look at how cells work on the micro-scale it looks a lot like cancer. They constantly divide and try to proliferate by allocating and using resources. Th

If you look at how cells work on the micro-scale it looks a lot like cancer. They constantly divide and try to proliferate by allocating and using resources. The only thing keeping them in check is basically the "cellular honor code". You can certainly try to make it less likely any given set of cells breaks the honor code but you can't "cure" cancer. It's an inherent property of multi-cellular life. Not unlike bee and ant colonies. There is always one queen (or several) but sometimes there will be a rogue queen born that bifurcates the colony. Bees and ants go to great lengths to avoid these situations but the way colonies are set up and structured rogue queens are an unavoidable part of the colony given a long enough timeline. I characterize scurvy as a sub-optimal stable operating state where optimality can be restored. Cancer does not have similar characterization. It's more like an unstable runaway loop. But I'm neither a biologist nor a doctor. My understanding is basically a bunch of analogies between game theory and general systems in the context of biology and maybe that's not the proper set of analogies for the problem at hand. In that context cancer is the breakdown of feedback loops that keep the system stable.

thaumasiotes 10y ago
> I characterize scurvy as a sub-optimal stable operating state where optimality can be restored. This makes no sense. It's not a stable operating state. Vitamin C is necessary to hold your cells together. Scurvy is the failure path of not having vitamin C; it is a transition from "healthy" to "dead". > cancer is the breakdown of feedback loops that keep the system stable OK, but this is exactly what scurvy is. They're just different feedback loops. Infection by foreign bodies is also "the breakdown of feedback loops that keep the system stable". Your objection applies to everything, which makes it completely meaningless when you apply it to cancer specifically.
- obstinate 10y ago
  This whole conversation reminds me of http://lesswrong.com/lw/iv/the_futility_of_emergence/ http://lesswrong.com/lw/iv/the_futility_of_emergence/. Claims like "breakdown of feedback loops that keep the system stable" are basically just a long way of saying, "for reasons I don't understand." All things happen for reasons, and if it's on the bleeding edge of human understanding, or beyond current science, it'll likely be for reasons you don't understand. That does not mean that no entity will ever be able to understand. It's a little frustrating honestly. Don't people see that most things seem impossible until they aren't? Just two years ago a lot of people were quite confident that computers would never surpass humans at Go. https://www.reddit.com/r/baduk/comments/2wgukb/why_do_people_say_that_computer_go_will_never/ https://www.reddit.com/r/baduk/comments/2wgukb/why_do_people... This is one of dozens of such links you could find from that period. Much moreso ten years ago. I get that cancer is a horse of a different color, but come on. If you are confident that ANYTHING will be impossible in 200 years, besides things which are physically so . . . well, I just cannot agree.
  - dkarapetyan 10y ago
    Stable/unstable/negative/positive feedback loops are technical terms in control theory (https://en.wikipedia.org/wiki/Negative_feedback https://en.wikipedia.org/wiki/Negative_feedback). I'm using those terms for specific reasons. I don't quite see what you're objecting too. Studying biology in the context of systems and control theory is a pretty well-trodden path (https://simple.wikipedia.org/wiki/Krebs_cycle https://simple.wikipedia.org/wiki/Krebs_cycle). Much of modern pharmaceutical research is actually about uncovering the chemical governing loops (another technical term) and affecting them to achieve positive outcomes. Cell division is an unstable positive loop that requires dampening with negative feedback loops at higher organization levels. When those negative feedback loops break down you get an unstable positive loop in the form of cancer. So you see how having cell division in a multi-cellular context can not be "cured" of cancer? You'd need to stop cell division and somehow figure out a way around entropy. Cells divide to renew/reset and shed accumulated environmental damage. So no matter what you do as long as you have a system organized around unstable processes like this you will always have a control problem when the negative control mechanisms stop working.
    - thaumasiotes 10y ago
      As I've already pointed out to you, every biological system is a feedback loop in the sense you describe. Feedback loops are how you defecate, how you blink, how you move, and how you choose how much of what to consume. Feedback loops regulate the activity of your immune system and seal the holes in your skin when it's punctured. This doesn't distinguish cancer from anything else.

thaumasiotes 10y ago

> I characterize scurvy as a sub-optimal stable operating state where optimality can be restored. This makes no sense. It's not a stable operating state. Vitamin C is necessary to hold your cells together. Scurvy is the failure path of not having vitamin C; it is a transition from "healthy" to "dead". > cancer is the breakdown of feedback loops that keep the system stable OK, but this is exactly what scurvy is. They're just different feedback loops. Infection by foreign bodies is also "the breakdown of feedback loops that keep the system stable". Your objection applies to everything, which makes it completely meaningless when you apply it to cancer specifically.

obstinate 10y ago
This whole conversation reminds me of http://lesswrong.com/lw/iv/the_futility_of_emergence/ http://lesswrong.com/lw/iv/the_futility_of_emergence/. Claims like "breakdown of feedback loops that keep the system stable" are basically just a long way of saying, "for reasons I don't understand." All things happen for reasons, and if it's on the bleeding edge of human understanding, or beyond current science, it'll likely be for reasons you don't understand. That does not mean that no entity will ever be able to understand. It's a little frustrating honestly. Don't people see that most things seem impossible until they aren't? Just two years ago a lot of people were quite confident that computers would never surpass humans at Go. https://www.reddit.com/r/baduk/comments/2wgukb/why_do_people_say_that_computer_go_will_never/ https://www.reddit.com/r/baduk/comments/2wgukb/why_do_people... This is one of dozens of such links you could find from that period. Much moreso ten years ago. I get that cancer is a horse of a different color, but come on. If you are confident that ANYTHING will be impossible in 200 years, besides things which are physically so . . . well, I just cannot agree.
- dkarapetyan 10y ago
  Stable/unstable/negative/positive feedback loops are technical terms in control theory (https://en.wikipedia.org/wiki/Negative_feedback https://en.wikipedia.org/wiki/Negative_feedback). I'm using those terms for specific reasons. I don't quite see what you're objecting too. Studying biology in the context of systems and control theory is a pretty well-trodden path (https://simple.wikipedia.org/wiki/Krebs_cycle https://simple.wikipedia.org/wiki/Krebs_cycle). Much of modern pharmaceutical research is actually about uncovering the chemical governing loops (another technical term) and affecting them to achieve positive outcomes. Cell division is an unstable positive loop that requires dampening with negative feedback loops at higher organization levels. When those negative feedback loops break down you get an unstable positive loop in the form of cancer. So you see how having cell division in a multi-cellular context can not be "cured" of cancer? You'd need to stop cell division and somehow figure out a way around entropy. Cells divide to renew/reset and shed accumulated environmental damage. So no matter what you do as long as you have a system organized around unstable processes like this you will always have a control problem when the negative control mechanisms stop working.
  - thaumasiotes 10y ago
    As I've already pointed out to you, every biological system is a feedback loop in the sense you describe. Feedback loops are how you defecate, how you blink, how you move, and how you choose how much of what to consume. Feedback loops regulate the activity of your immune system and seal the holes in your skin when it's punctured. This doesn't distinguish cancer from anything else.