Age A Byproduct of Cancer Defense?

A reader writes "The International Herald Tribune has an article which says, in brief: they have discovered that aging in mice seems to be a byproduct of the chemicals that prevent cancer" If true, that's quite a double edged sword - avoid death, to cause it later.

Comments

There goes one industry down the toilet!

[pgrote]

Man o man are these guys in for a surprise:

http://www.google.com/search?q=anti-aging+pills

Especially these folks:

http://www.pure-milk-calcium.com/immunocal.htm

This product is supposed to prevent cancer by extending your life :-)

Re:There goes one industry down the toilet!

[TheGreenLantern]

Well, in that case, the ??? actually equals "Market to a man's fear of death and desire for immortality". People have been making money off of that for thousands of years.

Re:There goes one industry down the toilet!

[schon]

"Market to a man's fear of death and desire for immortality". People have been making money off of that for thousands of years.

Really? Do you have any names?

If someone has been making money for thousands of years, I'd say their claims are pretty well-founded :o) :o) :o)

Re:There goes one industry down the toilet!

[shayne321]

Really? Do you have any names?

Err, two words: Organized Religion

If someone has been making money for thousands of years, I'd say their claims are pretty well-founded

Well, that's debatable.. I'm not going there, though.. :)

Shayne

Makes sense

[corporatemutantninja]

In the environment where we did most of our evolving very few people lived to "old age" before succumbing to a number of other dangers, so something that kept cancer at bay for a while at the price of guaranteeing death after a few decades probably seemed like a good deal. Kind of like the 640k limit. "That ought to be enough for everybody."

Aging and Cancer

[Renraku]

Chemicals that prevent or help prevent cancer usually tamper with cell division. If cellular division is in some way interrupted or affected by anti-cancer agents, then aging more than normal can easily occur. It goes back to one's preference. Long, suffering life or short, fulfilled life?

Re:Aging and Cancer

[oooga]

Not quite. Ender had no such affliction. In fact, Ender lived to be several thousand years old. Bean was the mutant.

Wow

[TheGreenLantern]

This sort of puts a whole new spin on this whole "Cure for Cancer" thing. The study seems to suggest that cancer is inevitable, and any attempts by our body to avoid it result in our own death.

Seems to me that if this is the case, it would have some serious repurcussions on how we currently understand how our bodies work. What is it about our physiologies that makes cancer such an irresitible force?

Re:Wow

[Tackhead]

> This sort of puts a whole new spin on this whole "Cure for Cancer" thing. The study seems to suggest that cancer is inevitable, and any attempts by our body to avoid it result in our own death.

Well, of course it should. These scientists are in contravention of the GMCA - Genetic Modification Copyright Act.

God licenses His creatures to operate a DNA-replication machine for a certain number of years, depending on the sort of DNA involved. Mayfly licenses are good for a day or two. Giant redwood licenses have expiry dates measured in millennia.

This is merely the DNACCA (DNA Copyright Control Association) invoking "self-help" on behalf of its client (JHVH-1, a.k.a. "God") whenever a licensee reverse-engineers its DNA with the intent of circumventing the digital rights management technology supplied with each organism.

(Just great, now we're gonna have to put up with 1000 years of Jack Valenti and Hilary Rosen and Michael Eisner saying they're not about making money, they're only doing God's work on a human scale...)

Re:Wow

[Daniel Dvorkin]

We've been doing immorality for quite a while now. I'd say we're not only ready for it, we're very good at it.

Immortality, now, that's another question ...

Re:Wow

[Otter]

This sort of puts a whole new spin on this whole "Cure for Cancer" thing. The study seems to suggest that cancer is inevitable, and any attempts by our body to avoid it result in our own death.

You have it backwards -- controlling runaway growth is vital, and our bodies have it at the cost of aging and senescence. Attempts to halt or reverse aging would likely result in runaway cancer.

What's new here, by the way, is the effect of p53. The tradeoff between aging and cancer has been clear for a while and suspected for decades -- Hemos reported on a project that supposedly beat the problem back in 1998.

What about my immortality bands!?

[mblase]

Is Alex Chiu's miracle Eternal Life Device going to give me cancer now? I can't believe it! The man is a fraud!

This goes against everything I've ever been taught. I'm beginning to put more and more stock in that time cube thingy every day....

Evolutionary balance?

[pdqlamb]

"Too much p53 and you get this aging effect. Too little and you get cancer. My guess is that evolution has evolved just the right level."

Would somebody explain to me how evolution would play in this finely-tuned scenario? In the U.S. our average lifespan is over 70 years, yet most women pass menopause around age 45. There's a 25 year lifespan discrepancy, in which evolution has no effect, because the population (at least of women) can't reproduce!

Re:Evolutionary balance?

[zulux]

There's a 25 year lifespan discrepancy, in which evolution has no effect, because the population (at least of women) can't reproduce!

In most primate cultures, old females still help with rearing the young. There is a hypothesis that this is the reason that females live longer than males - an old male is useless as a 'hunter' while an old femail is moderatly usefull as a child raiser.

Re:Evolutionary balance?

[Reality Master 101]

There's a 25 year lifespan discrepancy, in which evolution has no effect, because the population (at least of women) can't reproduce!

That's an oversimplification of evolution. Evolution cares about maximizing survival of the species. Reproduction is only one factor in that. If reproduction were everything, we would never have split into male/female, since that obviously reduces the ease with which we reproduce.

There are many things that people can do after child bearing to help propagation, such as protection, food production, education or labor.

Re:Evolutionary balance?

[homebru]

an old femail is moderatly usefull as a child raiser.

Older females are bloody marvelous at raising children and don't ever forget it.

Don't make me talk to your Mama 'bout this.

Re:Evolutionary balance?

[Arrgh]

Evolution has nothing to do with the differential survival of species, and everything to do with that of genes (individual organisms and close relatives, by extension).

Here's a nice quote on the subject from something I just Googled up:

Recall "suicidal" lemmings. Early biologists believed that lemmings (a) practice mass suicide and (b) that this trait is an adaptation benefiting the group. They reasoned that if the lemming population exceeds the carrying capacity of the local environment (if they exhaust food supplies) that the group will become extinct. To prevent group extinction, lemmings kill themselves. The gene for mass suicide is an adaptation benefiting the group to the disadvantage of the individual.

This explanation has several problems. First, lemmings don't kill themselves. They migrate to new areas. They are excellent swimmers. By swimming across fjords in groups, an individual lemming is less likely to be swallowed by predators (safety in numbers).

Second, a gene for suicide will not persist. Vehicles (lemmings) with the suicide gene do not reproduce?they kill themselves. In a population of lemmings with suicide genes, consider that a non-suicidal mutation would be very successful. If some lemmings refrain from killing themselves, they would be reproduce more than suicidal individuals and nonsuicidal genes would quickly predominate.

Richard Dawkins has written about this common misconception at length.

Re:Evolutionary balance?

[statusbar]

IANAGM (i am not a genetics major) - But - Couldn't a gene for suicide persist if it were manifested as a recessive trait?

--jeff

Re:Evolutionary balance?

[enkidu]

So let's say we have a species that produces three types of individuals: Males, Females and "Helpers". The helpers don't reproduce, but let's say they are super protective of the herd and fight off preditors. They're not just going to die off in one generation, because they are produced randomly from the mating of males and females. Ah, but if we get this mutation that causes them to not be produced. Natural selection takes over -- the herd that has the protectors is going to be more successful than the herd without them, and thus is (on average) going to survive better. They will win the war of resources.

But "helpers" can't be produced "randomly". There has to exist genes or combinations of genes which express themselves as "helpers". This will eventually lead to "Free loaders" or members of the species with no "helper genes" reducing the number of helper genes because they'll always leave more copies of their genes than those who need to expend energy creating "helpers" who don't reproduce.

Clearly the members of a species interact with each other in very complex ways, and these complex ways contribute to the survival of the species as a whole. Wolf packs, for example, have developed successful survival strategies that depend on group behavior.

You're confusing cultural information with genetic information. Just because the members of a species have evolved genes which allow them to interact with each other in very complex ways and pass down a culture of sorts (memes) doesn't imply that the successful reproduction of genes is driven by anything other than genes. The wolf pack passes down memes (hunting techniques) because it is to the benefit of their genes and memes that they do so. do you really think there are no behaviors in nature that are intrinsic to a species that simply foster overall survival rather than simple survival of the individual?

Good point. Maybe not overall survival, but perhaps survival of the behavior itself. That would make groups of common culture (wolf packs if you will) analogous to individuals with reference to memes and genes. That is memes are to culture groups" as genes are to individuals... Hmmm.

Now that I think about it, it is possible for meme's to evolve which mutually benefit the genes which created the conditions for them. But again, the memes are in it for themselves :-). A meme which does not contribute to its (the memes) survival will not perpetuate itself. Maybe this could lead to meme reproduction and evolution which supercedes the need to maintain genes. Perhaps the creation or transference of intelligence to non-genetic vehicle would be such a leap.

Some interesting food for thought. Many thanks for an interesting insight...

Re:Evolutionary balance?

[csbruce]

According to the alt.folklore.urban FAQ, Disney caused people to believe that Lemmings suicide in march to sea. During the filming of the 1958 Disney nature documentary White Wilderness, the film crew induced lemmings into jumping off a cliff and into the sea in order to document their supposedly suicidal behavior.

I wonder...

[TheGonzoKid]

Does this mean that since modern day man has increased contact with carcinogens, evolution will now favor those with higher cancer resistance and therefore shorter life-spans?

Think of the children

[mblase]

The average lifespan is only that long thanks to modern advances in medicine, disease cures, etc. Without them, the average human could expect to live maybe 50 years, although menopause might also come a little earlier.

But you can't think of those years as being wasted. After all, if a woman has children as late as 40, she'd certainly like to raise them to adulthood (and then help them learn to raise their own children) before she dies.

Re:Think of the children

[geekoid]

wrong.
The "average" life span is increasing do to the lowering of the infant mortality rate.
if took the aerage life span of anybodoy who at least lived until they where 5, would would findg that the average age has increased slightly.

Re:Think of the children

[MarcoAtWork]

Do you have any links/info that corroborate your assertion?

A *lot* of people I know would have died much earlier than they did (or they aren't dead yet, me included) due to illnesses they contracted after age 5...

Considering all of the people older than 5 going in hospitals for heart surgery, appendicectomies, assorted cancer removals etc. that go on living for decades afterwards (rather than dying), I find it counter intuitive that a lower infant mortality is the only reason why the average lifespan has increased so much during the past decades.

Note that I don't necessarily think it's wrong, mind you, just very counter intuitive, that's why I'd like to know if you have some sort of proof to back your statement with.

I know a woman who has stopped aging...

[Rude Turnip]

she's been 35 years old for about 10 years now.

This just in!

[Papa Legba]

It has now been discovered that the leading cause of cancer in labratory mice is.....

Scientists!

Please take note and live you life accordingly.

Re:This just in!

[greenfly]

When rats get cancer they get it big time. As in, they get a huge mass that sticks out from their body. It's pretty easy to notice, and it grows bigger and bigger. Some vets will surgically remove it, of course there is no guarantee that it won't just grow back (and it costs quite a bit for a pet you probably paid a few bucks for at most).

Re:This just in!

[Monkeychunks]

All joking aside, this shows how flawed the study of human cancer in rodents is. It's true, many rodents are very succeptible to cancer, most of the time from stuff which is not carcinogenic to a person. So, if we relied on rats to tell us about human cancer, we'd probably have to live in bubbles, but we, uh, don't.

Re:This just in!

[krmt]

So what would you do instead? Stick the cancer in people to get really accurate results?

And you do realize that when we study cancer in rats, it's human cancer cells that get put in the rats? Granted, it's not the same thing, but it's a good model to start from. Unless you'd like to volunteer to be a test subject?

Opposite ends of the spectrum

[nick_burns]

You could think of death as the end of cell growth, whereas cancer is cell growth gone out of control.

The more progress I see...

[Zen Mastuh]

...the stronger my belief in a creator. Over the last century we have been in a race to end death through bio-chemistry/bio-engineering. Now we are getting closer to the imaginary finish line and many people believe now that all cancer will be curable or preventable within a few years. Now we find that aging may fend off cancer.

Silly mortals! I propose that whomever designed us intentionally created these apparent paradoxes to force all doubters to eventually believe.

Re:Just Cancer Treatment?

[Anonymous Coward]

Ancient texts with people thousands of years old are explained by the lack of digital watches.

:)

Seriously, its the product of an oral tradition. Ever play the telephone game?

Interesting news, but not totally unexpected

[jafuser]

In biology, we were taught that each chromosome ends in a telomere (almost like those little plastic cylindrical thingies on the end of shoestrings) which doesn't do anything useful, but each time the cell divides, the telomere gets shorter. I'd imagine once the telomere is gone, the end of the chromosome would begin to "fray" as well, resulting in something equilvalent to a mutation, or maybe just a simple death of the cell (without the ability to divide further)

I've read that in cancerous cells, the telomeres don't shorten each time the cell divides, so there's no system in place to stop the cell from dividing forever (and all of it's children cells, etc.).

A reasonable hypothesis for why controlled growth through telomeres is necessary is to prevent mutations from a long series of copies (copies of copies, etc). This way, a "series" of cells only last for a fixed number of generations. After so many, the series stops. Then the stem cell(s) can take over and start a new "first generation" cell which can be the start of a new series of cells.

As we get older, perhaps the stem cells themselves start to degrade or become mutated (possibly causing cancer), and are no longer able to produce good "first generation" cells. As an example, this could be why we develop skin blemishes as we get older. Just imagine what's happening to other genetic attributes.

It's my personal theory that the process of aging is actually just the process of various parts of our body mutating to a small degree. For example, one little DNA pair mutated in a skin stem cell, and suddenly you have a freckle.

I always figured that given the knowledge that's taught in regular high-school biology, most people could figure out that the tradeoff of preventing aging is the increased risk of cancer (since cancer cells could go on forever if supplied with the nutrients necessary for cells to live).

*shrug* I dunno...

Read the real sources!

[bradbury]

One of the things that continually disappoints me about /. is the degree to which people will comment on things without slightest knowledge of the subject under discussion. One of the things that I find appealing is when someone who actually knows something provides a useful interpretation that abstracts useful data for people who aren't particularly well informed in an arcane knowledge base.

I'm speaking here as founder and president of what was the 2nd largest biotechnology company in the U.S. focused on the molecular biology of aging during the mid-'90s. So we will assume for the sake of improving the discussion I'm moderately well informed in this arcane branch of knowledge.

Point #1: If you read something scientific or technical in the "popular" press, never assume that they managed to interpret it properly. If reporters don't have an education in a particular discipline, they are not likely to understand the subtleties of what is being discussed. Always go back to the most scientific sources you can get access to. Most of the readers are presumably qualified to evaluate arguments on technical merits (this is the /. forum!). Learn the jargon and if you don't understand something find an expert and ask questions (or post to the forum -- you never know when an expert might be lurking).

Point #2: Never assume a /. poster knows what they are talking about (or has verified what they may have copied or concluded from popular press). Case in point: "aging in mice seems to be the byproduct of the chemicals that prevent cancer". The material under discussion is a mutant p53 protein which is the byproduct of a modified p53 gene. It is not by anyone familiar with discussions in this field a "chemical". The p53 protein weighs tens of thousands of daltons and has multiple "active" functions -- most molecules considered "chemicals" weigh less than a few thousand daltons and have few, if any, "active" functions.

From the Nature news report: "they created mice with a chunk missing from one copy of the gene". Translating this into "programmer" terms -- this is in effect replacing 1 of 2 instantiations of an essential subroutine in an ~30,000 subroutine system with a subroutine that has had some of its lines deleted. How do you draw conclusions as to what is going on in that situation? Unless you know what lines were deleted and what the purpose of those lines was you have relatively little hope of drawing conclusions that would allow you to debug the system (at least IMHO). You certainly cannot discuss what the situation means in any intelligent fashion.

All of that being said, I'll provide my "spin" on the results. The normal p53 protein is a "gatekeeper" protein. Its purpose is to determine whether or not DNA damage is present (i.e. whether your program has been corrupted). If too much damage is present it induces cells to commit apoptosis (cellular suicide). If less damage is present, it delays cellular replication (copying) until the damage that is present can be repaired (calling the ECC subroutines). So it acts as a brake on the replication of mutated/damaged DNA and an executioner for cells that are so far beyond the error-correction subroutines that they represent a threat to the entire organism. In larger organisms (which have more cells and are therefore at greater risk of developing a "mutant" program and therefore cancer [which is unregulated cellular replication]) it is important to constrain replication. So humans, in contrast to mice may have a p53 which strongly constrains cellular replication. { Alternatively they may have "redundant" subroutines like telomere shortening (mice have very long telomeres, humans do not) which function as "backup" programs that function to limit cellular division and therefore the development of cancer. (This is based on the concept that short telomeres inform cells to "stop dividing" just as "damaged DNA" [through the p53 protein] cause cells to stop dividing.) } The extent to which short telomeres may resemble "damaged" DNA (and therefore activate the p53 "subroutines") is unclear (to me) at this point. [This is a fairly hot topic of scientific debate.]

If we view cancer and aging as complementary ends of the see-saw -- allow too much cellular replication and one gets cancer -- allow too little cellular replication and those parts that wear out are not replaced, resulting in aging, and one may be able to interpret the results of this study. The part of the p53 gene that was deleted probably served to function to "remove" the block against replication or "enable" the replication function. So what may be occuring is that the mutant p53 gene may be detecting damage, blocking replication, but then when the damage is repaired the defective p53 may not be allowing replication to proceed. Thus you have very effective anti-cancer properties but as one gets older there are fewer and fewer cells available to replace those that are lost. Net result: accelerated aging.

Now, this result need not be pessimistic. As Tom Kirkwood, one of the world's leading gerontologists pointed out in the Nature article, "We could be able to pick a path through the molecular mechanisms of ageing without making cells more tumour-prone. 'There's no reason why you shouldn't get greater defence against cancer and greater longevity.'"

As a once upon a time programmer -- I encourage people in the software industry -- "View genomes as programs -- lets figure out where the bugs are and then lets go fix them."

No They Didn't

[krmt]

Single cell organisms pretty much live forever until they are eaten, starve, or encounter an enviromental hazard.

Care to back that up? I have never seen any kind of data supporting the assumption that single cell organisms live forever, given those kinds of conditions, and without any kind of data, I won't believe it.

The reason being that thermodynamics (or chaos theory, or whatever) says that you're wrong. Any system as complex as a living cell, even something so simple as a yeast cell or E coli can not maintain that level of organisation for long. The cell is very thrifty with its organization, to be sure, but it is not infinitely so. That's why reproduction and evolution are so critical, because no single system can survive by itself for too long, so it must rebuild itself from scratch. Yes, you can put these systems in to hibernation, but that isn't really life functioning in any way shape or form until it's revived.

And of course pre-programmed cell death wasn't present in single cell organisms, it'd be counterproductive for an E coli to simply kill itself. Preprogrammed cell death does not kill the entire organism, and it obviously be detrimental if it did.

And as for sex and evolution evolving together, there are single celled organisms that have sex via plasmids. Granted, it might not be the "one chromosome from each parent" that we are used to in humans, but it is still genetic exchange by conjugation. There is no apoptosis here either.