Research suggests bigger human brains may also explain higher incidence of cancer

Oct 16, 2012 by Bob Yirka weblog
Viability of human and chimpanzee primary fibroblasts after treatment with staurosporine. Credit: (c) PLoS ONE 7(9): e46182. doi:10.1371/journal.pone.0046182

(Phys.org)—Researchers from the Georgia Institute of Technology have published a paper in the journal PLOS ONE highlighting their study comparing the rate of cell apoptosis between humans, chimps and macaque. Their finding that human rates were the slowest of the group led them to suggest that such a slow rate may account for a larger brain size in humans and possibly increased rates of cancer.

is a process whereby cells self destruct when they become old, damaged or are no longer needed. It's a process that allows for body parts to grow into their correct shape and also helps to prevent the growth of tumors. In this new research, the team studied the rates at which cell apoptosis occurs in different primates, theorizing that a slower rate would allow for less apoptosis pruning of old allowing for larger . This idea has previously been backed up by other studies that have shown that mice with protein executioner caspases disabled – which regulate the rate of apoptosis – develop larger than normal brains.

To learn more about the different rates of apoptosis in primates, the team applied apoptosis stimulating chemicals to the skin of test subjects and found that compared to chimps and macaque, human cells appear reluctant to self destruct. Fewer skin cells died and there was less deformation, a sign that a cell is preparing to signal its demise.

But a slower rate of apoptosis has also been shown to increase the risk of developing , which led the team to theorize that the same mechanism that led to humans having larger brains, also led to increased rates of cancer. One hitch in that assumption, however, as Todd Preuss of the Yerkes National Primate Research Center, points out in a conversation with New Scientist, is that there isn't enough cancer rate data available in other primates to say for certain whether human rates are higher or not. He adds that slower rates of apoptosis in humans may account for longer life spans, which he says is also likely partly responsible for larger brains as it allows more time for learning and teaching offspring.

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More information: Arora G, Mezencev R, McDonald JF (2012) Human Cells Display Reduced Apoptotic Function Relative to Chimpanzee Cells. PLoS ONE 7(9): e46182. doi:10.1371/journal.pone.0046182

Abstract
Previously published gene expression analyses suggested that apoptotic function may be reduced in humans relative to chimpanzees and led to the hypothesis that this difference may contribute to the relatively larger size of the human brain and the increased propensity of humans to develop cancer. In this study, we sought to further test the hypothesis that humans maintain a reduced apoptotic function relative to chimpanzees by conducting a series of apoptotic function assays on human, chimpanzee and macaque primary fibroblastic cells. Human cells consistently displayed significantly reduced apoptotic function relative to the chimpanzee and macaque cells. These results are consistent with earlier findings indicating that apoptotic function is reduced in humans relative to chimpanzees.

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TheGhostofOtto1923
2.7 / 5 (30) Oct 16, 2012
More evidence that our brains have been driven into a pathological and unsustainable state by the unnatural rigors of competition among weapon-wielding tribalists.

It made us clever but it also made our brains prone to damage, defect, and dysfunction. They are too resource-hungry and delicate, and begin to decrepitate shortly after adolescence.

The sooner we can replace them the better.
Feldagast
4.2 / 5 (5) Oct 16, 2012
Couldn't have anything to do with the toxic substances we consume on a daily basis versus natural foods the rest of the worlds animal population ingest? Maybe they ought to investigate the number of instances of cancer in domestic animals versus wild counterparts, since we are also feeding them some of the same toxins?
Estevan57
2.1 / 5 (32) Oct 16, 2012
More evidence that our brains have been driven into a pathological and unsustainable state by the unnatural rigors of competition among weapon-wielding tribalists.

It made us clever but it also made our brains prone to damage, defect, and dysfunction. They are too resource-hungry and delicate, and begin to decrepitate shortly after adolescence.

The sooner we can replace them the better.


Speak for yourself, Otto.

I offer as example for your hypothesis ----- YOU.

If anyone would qualify as a pathological, unatural, weapon wielding, damaged, defective, dysfuntional, delicate, decrepit, adolescent tribalist it would be you.
HannesAlfven
2.8 / 5 (9) Oct 16, 2012
Re: "Couldn't have anything to do with the toxic substances we consume on a daily basis versus natural foods the rest of the worlds animal population ingest?"

Yes, you're right, but unfortunately, only 6% of medical doctors are trained in nutrition (See documentary Food Matters) ...

Re: "Maybe they ought to investigate the number of instances of cancer in domestic animals versus wild counterparts, since we are also feeding them some of the same toxins?"

In a sense, this work has already been done -- but it was done on humans. It's called the China Study, and it very clearly implicated a number of dietary sources as being the most fundamental cause for cancer: refined sugar, meat and dairy being the top three contenders.

Cancer research is almost a complete farce. Watch the Burzinsky documentary on Netflix if you don't believe me. There is literally no money in teaching people to eat properly. And nobody wants to be told that they can't eat cheese.
Torbjorn_Larsson_OM
5 / 5 (4) Oct 16, 2012
@ TGO: "More evidence that our brains have been driven into a pathological and unsustainable state by the unnatural rigors of competition among weapon-wielding tribalists."

Never mind the evidence then, observing that chimps are the most aggressive ape (and the bonobo least) and the larger brained gorilla less aggressive than humans. In other words, if you have something inane to rant about, use any verbal club you can think of to go "TGO SMASH!" (O.o)
Torbjorn_Larsson_OM
3.7 / 5 (3) Oct 16, 2012
@ HannesAlfven:

And while I compose a reply to TGO you do exactly the same thing. Cancer rates are averaged over populations with the food factor taken out.
HannesAlfven
3.3 / 5 (11) Oct 16, 2012
Re: "Cancer rates are averaged over populations with the food factor taken out."

Angiogenesis grows capillaries to cancerous tumors. The trick to avoiding cancer is to foremost avoid stress -- which invokes a fight-or-flight response within the body. This response involves organ shutdown -- and one of the systems to shut down is the immune system. We know from looking at corpses that the body is littered with microscopic tumors at all times. When the immune system is operating properly, these microscopic tumors never become a threat.

However, certain foods will tend to grow capillaries to these microscopic tumors, permitting them to grow in size until they can threaten a person's life. This is called angiogenesis.

Illnesses like cancer and heart disease are first-world diseases. They result from our diet. My girlfriend works in the food industry. Nearly every single item on the shelf is filled with exotic chemicals. To think this has no effect is pretty crazy sh*t IMO.
HannesAlfven
3.1 / 5 (11) Oct 16, 2012
What these food companies do is survey consumers for feedback on what TASTES good. The process has absolutely NOTHING to do with health. If, for instance, they get some feedback that the consumers don't like the carrots in the microwave dish, then the food scientist is not fazed. HE WILL ADD SYNTHETIC CARROT FLAVORING TO THE REAL CARROTS in order to improve the consumer feedback.

This is happening FOR EVERY SINGLE PROCESSED FOOD PRODUCT ON THE GROCERY SHELF.

So, the first step is to stop eating that garbage. The next step is to learn about the China Study and angiogenesis. We can very easily run our country into the ground if we refuse to look at food as a source for cancer. The government and public are picking up the tab for corporate pursuit of profits, and the corporations couldn't care less. To them, cancer is an EXTERNALITY.
TheGhostofOtto1923
2.7 / 5 (26) Oct 16, 2012
If anyone would qualify as a pathological, unatural, weapon wielding, damaged, defective, dysfuntional, delicate, decrepit, adolescent tribalist it would be you.
Hello greasy troll. I have taken a little time to document your decrepitude on my profile page. Have you seen it? Lying, stalking, paying little girls to gangrate for you... You are a credit to your subspecies lol.

I have yet to document your scummy sex comments but I am sure your niece has noticed them.
TheGhostofOtto1923
2.8 / 5 (27) Oct 16, 2012
Never mind the evidence then, observing that chimps are the most aggressive ape (and the bonobo least) and the larger brained gorilla less aggressive than humans.
Ongoing research is revealing that 70s human-hating preconceptions about hippy primates are giving way to reality... Bonobos are also hunters and warmakers, and can be expected to fight to defend their families and their territory with the same ferocity as any other animal, including us.

Apparently only humans however are capable of fantasizing about things like tabula rasa, noble savages, non-violent primates, dancing Mickey mice, and a life everafter. I submit that this ability has no survival value. Even bonobos do not pray for deliverance from jackals.

Another indication of endemic cranial pathology.
Estevan57
2 / 5 (28) Oct 16, 2012
Here are the links you keep saying are mine. It kind of looks like they are not mine after all... and that makes YOU a liar.

In the comments section.
http://phys.org/n...rth.html

Why is it that you have 2 to 5 times as many votes as anyone else? Have you been busy? Unnatural rigors of competition perhaps.

You are truly a ghost of a man.
TheGhostofOtto1923
2.8 / 5 (27) Oct 17, 2012
Why is it that you have 2 to 5 times as many votes as anyone else? Have you been busy? Unnatural rigors of competition perhaps.
-This was because you pay little girls to gangrate me like you said. Per my profile page. Right?

Oh and uprate you I see. Minstrel_Cycle. Your suggestion for a name?

You shouldn't be stalking people and lying about these things esai. ALL you do is follow me around and shit everywhere. You dont do anything else. Are you a dog? Aren't you embarrassed? Do suckpuppets feel shame? Ha
dumdogslickthemselves
2.4 / 5 (25) Oct 17, 2012
I think he's a dog.
Arf_Arf_Arf_Arf_Arf_Arf
2.6 / 5 (27) Oct 17, 2012
Yes he does smell like a dog.
Feldagast
4.2 / 5 (10) Oct 17, 2012
Wow looks like someone actually went through the effort to make 2 new accounts just to post like an imbecile.
TheGhostofOtto1923
2.8 / 5 (25) Oct 17, 2012
Wow looks like someone actually went through the effort to make 2 new accounts just to post like an imbecile.
Yeah some people will even pay their little nieces to to create scads of suckpuppets like JewzRule, minstrel_cycle, and ottolickeeuranus to gangrate themselves and their friends upward and people they want to push around, downwards.

I see you are in the former category.

I also see that those posters above are not new.
diaper_dog_dick
2.7 / 5 (24) Oct 17, 2012
Yes he does smell like a dog.
I think he is adorable. For a dog.
Estevan57
2 / 5 (28) Oct 17, 2012
Feldagast - Close - Otto created these three in early 2011 , and he uses them to vote for himself and against others. Myself included.
They are all takeoffs of Dogbert, someone he was at "war" with at the time.

If "Dumbdogs" is followed into the "As us cuts back China...", page 5 or so you can see Ottos' efforts at raising his ranking.
Average votes per person 3.3, Otto: 13

Because he is ashamed at being exposed at his game he will accuse me of the same thing. It is a good defensive strategy, and hard to disprove. And when proved wrong as below he launches another salvo of accusations. Oh well.

By the way he is also lite, and is VERY active with this name.
Have a pleasant day.

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