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The article Scientists cure cancer, but no one takes notice claims big pharma and the media are ignoring dichloroacetate because it's out of patent protection - but that question is answered at Dichloroacetate (DCA) as a cure for cancer

The bit I'm interested in is where it says

In human bodies there is a natural cancer fighting human cell, the mitochondria, but they need to be triggered to be effective.

Do they fight cancer in any way, shape or form, or is the author mistaking them with midi-chlorians?

Also, are mitochondria cells?

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    Steve Novella has an interesting write up at Skepticblog: skepticblog.org/2011/05/16/another-cure-for-cancer – JasonR May 16 '11 at 14:07
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    Now add in PZ Myers: scienceblogs.com/pharyngula/2011/05/… and Orac: scienceblogs.com/insolence/2010/05/… – JasonR May 16 '11 at 14:28
  • Judging by the comments on the original Hubpages article, this publication is actually doing really a lot of harm. Might they perhaps be convinced of correcting it, or at least taking it down? – Konrad Rudolph May 16 '11 at 19:30
  • It's not on topic, because this question deals more with apoptosis and the mitochondria (even though the hubpages author seems terribly confused), but if anyone's interested as far as "natural cancer fighting cells" go, the body does have them. For the simplest explanation of them, search for tumor-necrosis factor, also natural killer cells. They're much more complex than I can sum up in a comment. – Monkey Tuesday May 16 '11 at 23:19
  • Everything you need to know about mitochondria (except for stuffed discovered in the last six years) can be found in Nick Lane's Power, Sex, Suicide: Mitochondria and the Meaning of Life. The power refers to their role as the power plants of the Eukaryotic Cell, sex refers to role of mitochondria in driving eukaryotes toward sexual recombination and multiple sexes, and suicide refers to their role in cell apoptosis. – user6767 Apr 14 '12 at 21:10
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Aside from their main function in cellular respiration, mitochondria play an essential role in the regulation of programmed cell death (apoptosis).

A variety of key events in apoptosis focus on mitochondria, including the release of caspase activators (such as cytochrome c), changes in electron transport, loss of mitochondrial transmembrane potential, altered cellular oxidation-reduction, and participation of pro- and antiapoptotic Bcl-2 family proteins. -- source

Cancer cells have to find a way to evade triggering apoptosis in order to survive, and the treatment of cancer often relies on triggering apoptosis.

For example, it is now clear that some oncogenic mutations disrupt apoptosis, leading to tumor initiation, progression or metastasis. Conversely, compelling evidence indicates that other oncogenic changes promote apoptosis, thereby producing selective pressure to override apoptosis during multistage carcinogenesis. Finally, it is now well documented that most cytotoxic anticancer agents induce apoptosis, raising the intriguing possibility that defects in apoptotic programs contribute to treatment failure. -- source

Strictly speaking the statement is wrong, mitochondria are not cells and they don't explicitly fight cancer. But they are involved in apoptosis, a very important mechanism against cancer. This sounds pretty much like a reporter trying to summarize a topic he doesn't understand.

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    +1 for the "reporter trying to summarize a topic he doesn't understand." Some of my best "misreporting" stories come from such incidents, like the time I was working in a lab hunting for aquaporin which was reported as "building super athletes" because one subject (out of 40) with nephrogenic diabetes insipidus happened to be a marathon runner. – user2767 May 16 '11 at 21:12
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No, mitochondria are not cells, they are organelles and reside inside the cells.

The statement is probably a simplification (or misunderstanding) derived from the observation that a lot of cancer cells get their energy from glucose:

Many cancer cells consume glucose avidly and produce lactic acid rather than catabolizing glucose via the TCA cycle, which is key for generating ATP in nonhypoxic normal cells. The avid uptake of glucose by tumors is the foundation for the detection and monitoring of human cancers by fluorodeoxyglucose positron emission tomography. CancerRes.AACRJournals.com

Mitochondria are often colloquially referred to as the cell's "power plant". It oxidizes glucose to produce ATP. From this it follows that if you could stimulate the mitochondria further, it'd consume glucose at higher levels, thus effectively "starving" the cancer cells that also consume glucose, and as such inhibit cancerous growth.

Note that the production of ATP from glucose is a key part of our metabolism. This is an end in itself, and I do not think it is reasonable to interpret the mitochondrial consumption of glucoses as an active adaption for fighting cancer.

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    The energy the mitochondria gain by consuming glucose would be available to the cancer cell. Cancer cells often don't rely on cellular respiration because they can't get enough oxygen, so they have to use glycolysis instead. Although for some reason they also often prefer glycolysis even if there is enough oxygen available (Warburg effect). – Mad Scientist May 16 '11 at 13:23
  • Yep, Mitochrondria are membrane-enclosed organelles, although it has been suggested that they may have been separate, and then become symbiotic and integrated with animal cells at some stage in animal cell evolution. – Chris Dennett May 16 '11 at 13:37
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    @Chris, that's the prevalent theory, but not "at some stage in animal cell evolution", but much, much earlier, during separation between Eukaryotes and Prokaryotes. No animal could have existed at that point, only very rudimentary single-cell organisms. – Aleadam May 16 '11 at 16:10
  • Ah, sorry. You're correct :) – Chris Dennett May 16 '11 at 16:14
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Mitochondria contain a large number of radicals. The good thing is that these radicals are safely tucked away on the inside of a cell wall which comprises the mitochondria.

In cell death, the cell wall sometimes fractures. I haven't been reading up on mitochondrial research recently, so I can't place the timing of the cell wall rupture prior to the cell death (which might indicate it is a causal relationship) or after the cell death (which would indicate a consequence of the preceding death). In either case, without a functioning mitochondria, nearly 80% of the energy available from glucose is unattainable, so mitochondrial damage and cell death are closely related.

One problem with combating cancer is that it's an overly broad description which applies to any unwanted / unregulated growth. Any malfunction of the cell where it stops responding to cues that regulate growth is called cancer. Normal cells detect their neighbors and slow down the growth process, while cancerous cells grow regardless of feedback signal(s). Sometimes this leads to localized starvation of sugars, oxygen, or other resources.

Human cells have a fail-safe in that they contain a protein p53 which is triggered under certain circumstances. This protein signals the cells to "cellularly age" meaning the cell will no longer be able to reproduce, but will maintain and repair itself. This cellular aging is based on a clock which seems to count its time in number of divisions. It has been a long time since I did such research, but if I recall correctly, a cell has about 90 divisions prior to aging.

Some cancers manage to disrupt this safeguard, and they are referred to as "growths", "benign tumors", "dead cancer cells", "non-cancerous tumors", etc. while active growths are generally referred too as cancer. In the research fields we view(ed) reality as it all being cancer, but some of it was "arrested".

There is a theory that cancer can be induced by damaging cellular components with free radicals. A leak in a mitochondria might allow damage to a cell, and depending on what is damaged (and to what degree) it might actually trigger a cancer. While the possibility exists, rest assured that it is so small that you manage to carry around multiple millions of cells for upwards of 80 years without guaranteeing that it will happen in a single cell.

This free radical theory is the reason why people believe that eating anti-oxidants can promote better health; however, I am not aware of any research (due to ignorance, not necessarily because it is a false theory) that indicates that anti-oxidants survive the transition from stomach to bloodstream, or that they get internalized from the bloodstream to the cellular cytoplasm.

While the public "knows" that cancer is a growth of existing cells, the entire public reaction is to deal with the problem as a disease. This dichotomy might be the reason that the public has so many misconceptions about cancer. We "catch cancer" and "get rid of it" in casual talk; but, in reality (with the exception of a very few viral cancers) there is no outside agent: one might as well be talking about catching a lung or a kidney. It requires quite a bit of discipline to readjust our thinking to "our bodies are malfunctioning".

As far as mitochondria, their role is to provide a cellular membrane where the process of the electron transport chain can occur. That provides both energy and free radicals. The energy is not tagged for a particular consumer, and a the cell that needs it to survive is the same cell that will use it when malfunctioning in a manner we call cancer.

  • Hi Edwin. There aren't any references here to back up your statements. You might like to add them to improve your answer. – Oddthinking May 16 '11 at 15:23
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    Sorry, I was a cancer researcher. While using myself as a reference isn't exactly kosher, it is an easy task to do when you are yourself. Note that my view of this chunk of the world was as it existed about ten years ago. Refinements have probably been made. – user2767 May 16 '11 at 15:47
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    @Oddthinking, links added. Of course, they aren't real references, as any yahoo can put stuff up on the internet (I know I have!). Cheers. – user2767 May 16 '11 at 16:13
  • “Note that cell death and cancer are not so closely related.” Sounds misleading, since cell death and cancer are actually strongly related – the former is down-regulated / disabled in the latter (it’s actually one of the classical hallmarks of cancer). Surely that’s what you meant but it may be misunderstood. – Konrad Rudolph May 16 '11 at 19:36
  • Sorry about the confusion, English is an imprecise language. Cell death and cancer are not positively correlated. Fabain mentioned Apoptosis, which is actually NOT the same thing as cellular aging, and Apoptosis is not generally seen as a regulatory agent to thwart cancer. Apoptosis, is programmed cell death, which is required during development (under certain circumstances). – user2767 May 16 '11 at 20:15

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