So the cancer cells went with the non-blocking, albeit slower algorithm. With aerobic, pipelines could get filled with ATP and end up blocking the essential NAD+. So the optimization was a loosely decoupled slower fermentation process over the faster aerobic process. Back pressure avoided and all that.
So tempting to go with analogies we are familiar with.
There is a relatively new theory saying that malignant, metastatic cancer cells behave like single cell organisms, and that cancer basically represents an unwanted return to our genetic roots; multicellular organisms used to be single cell organisms a billion years ago and the original genes might carry on within our DNA until today. But they should be switched off. Once they are switched on, the cells will stop cooperating with the rest of the tissue and start acting "selfishly", at others' expense.
This is known as "atavistic theory of cancer" and it is rather controversial, there are people who utterly hate it, not least because the original authors are not specialists in cancer treatment.
Part of this theory is that cancer cells "cannot help but switch to the previous single-celled metabolism, very inefficient compared to ours".
> There is a relatively new theory saying that malignant, metastatic cancer cells behave like single cell organisms, and that cancer basically represents an unwanted return to our genetic roots
It's not close to even 'relatively' being new. I was giving cancer talks that made mention of it back when I worked in cancer bio, just about 16 years ago now. I didn't come up with it, and it wasn't new then. I used it in talks to laymen, to give a very abstract idea of how cancer worked. But it fell into the category of "lies we tell children," because it was only true in the most abstract way, and utterly incorrect once you dug into any details.
The reason cancer bio people dislike it is because it's only true at the 10,000-foot, highly abstracted level. When you start digging into the granular level, its testable predictions rank between 'falsified' and 'irrelevant'. It doesn't produce any alternative lines for thinking about treatment, causality, etc. Especially given that the progress of a single cancer tends to be all about their interaction with the multicellular milieu - e.g., developing immune evasion, which isn't at all an "atavistic" trait, although it's one of the core hextad that defines malignant development. (On the contrary, it comes built-in for normal cells - they're now developing a novel immune evasion, to hide their newly altered antigens from the immune system).
e.g., "Cannot help but switch to previous single-celled metabolism" doesn't follow in any meaningful way from the thesis of atavistic traits. In fact, it doesn't predict at all the relationship between tumor size, distance from vascular supply, and anaerobic metabolism. "Cells without controlled growth will outgrow their vascular supply, requiring a transition to anerobic metabolism" does, however, and predicted the relationships we see. It's not "cannot help but engage with less efficient metabolism", it's "transition to relying on the only metabolism afforded to a highly-dysregulated cell that is not responsive to environmental signals that normally trigger or withhold growth." Normal unicellular organisms are responsive to those signals.
Yeah, I don't hate it - it's a cute metaphor. It's a nice way of thinking of cancer at the 10K-foot level. It's just also wrong at any closer level of inspection than that, which is why people whose job is to be elbow-deep in all of the nitty-gritty details of cancer can't help but look at it and go "please stop wasting my time."
Since you were a cancer researcher in a previous life, may I ask you a question I thought of commenting on another's comment?
If cancer cells have high metabolic requirements, couldn't you attack them by:
1. lowering the caloric intake of the patient
2. Making the glucose the patient intakes mildly radioactive, say with a beta or an alpha emitter [1]. As the patient is strictly kept on a low caloric diet, the radioactive glucose is consumed and expelled quickly (i.e. doesn't accumulate in the adipose (?) tissue).
Not so radioactive that the person is harmed but radioactive enough to pack an extra punch to the metabolically starved, and therefore stressed, cancer cells (who are drawing more of the glucose to themselves).
That should target cancer more specifically, and I guess it can be done in tandem with other techniques.
Is something similar done? I know that's how cancer is imaged, and the way I see it (I studied optics in a previous life) if you can image it, you should be able to destroy it.
[1] Say replacing the hydrogens in glucose with tritium. Hydrogen hopping will ensure that the water produced by metabolizing the sugar is homogeneously mixed, and therefore expelled with all the water loss mechanisms. According to wikipedia, TO2 has a half life of 12 days. I'd imagine you can lower that by pumping fluids into the patient.
There is a very interesting book around the metabolic route for treating cancer. It's called "Starving cancer" by Jane McLelland. It talks about using over the counter drugs and supplements that have been studied for their metabolic blocking properties for cancer, as well as changing the diet to reduce as much as possible the nutrients that cancer craves the most according to their metabolic phenotype. Most of the times it's glucose or glutamine, but the trick is to block as many metabolic pathways using the drugs so that mutation is prevented. Most of these drugs have their patents expired and are quite cheap. The author had a very aggressive form of cancer with less than 5% statistic survival rate and were able to survive and go back to NED (no evidence of disease). It's not exactly a substitute for standard therapy such as chemo, but there's many people who also went to NED just with her protocol.
I tried this back when I had cancer, and even though my survival rate was very high just on standard care, my tumor markers went way down almost to normal on the first cycle combined with Jane's protocol.
Unfortunately, the cancer industry and pharmaceutical industry won't really invest much money on clinical trials for expired patent, or even existing drugs in their portfolio. There are a couple of independent clinical trials going on, so far, with good results AFAIC.
Another very controversial, but interesting treatment for cancer that will probably never see the light is Chlorine Dioxide. And don't you dare write that on Facebook or YouTube because it'll be outright banned or deleted for "spreading misinformation". I have friends and persons I know that went to NED just on chlorine dioxide and diet. Having used it myself for many months with no negative effects, and, after chemo, I can't help but cringe every time someone tells me that it's "very toxic". Oh lord, you should have seen what chemo was like. Now, that was toxic.
If something is flagged by YouTube, it must be a really bad idea.
Chlorine isn’t too bad in terms of toxicity, or it wouldn’t be added to drinking water and freely sold for all sorts of purposes.
But there’s absolutely no reason to ingest it (or any other route of administration).
I guess it’s exactly because of it’s ubiquity that those of a conspiratorial mindset like it so much: it fits with the idea that there are obvious and easy answers suppressed by that mighty cabal of Bill Gates/Soros/some other Jews.
Chlorine sucks. It's added to water because the other major way of disinfecting water (ozone) is too transient to last all the way through the water pipelines. Nonetheless, they're often used in combination, to minimize the amount of chlorine needed. The only thing worse than chlorinated water is the diseases you catch by not having chlorinated water.
This is exactly my point. If anything, the effects of chlorine dioxide seem minimal or barely noticeable compared to chemo, and of course, much better than dying of cancer. I'm not saying that cancer patients should skip chemo, though!
I don't think you should get health advice from banned YouTube videos.
In fact for the average layperson, figuring out what's good information and what's bad information on YouTube or the internet in general is probably beyond their abilities. I know my dear mother, who I love, can't do it. I like to think I can, but I'm the least qualified person to judge that. I'm also not average.
But I want to point out that one of the main treatment options for cancer is Chemo, which is basically injecting/ingesting toxic substances in the effort to weaken or kill the cancer before killing the host. So chlorine could well work in the vein, but I wouldn't want to use myself as test subject A in an unregulated pre-clinical trial.
I think it really depends on your statistical survival rate. If you're almost guaranteed to die, there's less of a concern in using yourself as a test subject.
I don't agree with trusting YouTube blindly. I trust my friends and colleagues that have cured their cancer better. Also note that chlorine dioxide is not sodium hypoclorite. It's like comparing salt (which also contains chlorine) with sugar.
I wasn't sure what to make of what you said until you dropped this common fallacy used by MMS cultists.
All forms of oxidising bleach (chlorine gas, hypochlorite solution, chlorine dioxide, hydrogen peroxide, sodium perborate, etc) take effect by taking electrons from other matter. These reactions are able to "bleach" because pigments are often complex organic molecules which tend to decompose in presence of strong oxidizers.
The toxicity of chlorine dioxide is very well studied. Guess what, once absorbed it acts as a bleach/oxidizer in your blood, rupturing red blood cells and may lead to kidney failure as haemoglobin is released into the plasma.
The reaction is caused by the inhibition of glucose 6-phosphate dehydrogenase which is probably the tenuous link between consuming bleach and cancer treatment. While the enzyme is indeed a drug target that people have looked into, it is very unlikely to work by oral dosing because many healthy issue also rely on the enzyme to survive.
This, of course, has not stopped the MMS cult from claiming that their panacea cures every single ailment under the sun which has no medical basis whatsoever.
I'm not a doctor, but there seems to be some medical basis in some pathologies. If you are a doctor or scientist perhaps your input would be greatly appreciated in the following papers:
The chicken embryo study is interesting but chlorine dioxide is already known to be less toxic to birds. And your other sources clearly state that chlorine dioxide and chlorites suppress thyrioid function and haematopoesis in primates and humans. Is that supposed to be a good thing?
>Also, CDS is not MMS.
Out of curiosity, do you acidify the ClO2 solution before quaffing it? It's a ritual very well associated with MMS proponents but probably does more harm than good if the goal is to deliver chlorine to the body.
The results in monkeys seem to suppress thyroid function, but:
> No evidence of thyroid effects were detected in the serum of human volunteers who ingested approximately 1 mg/l. of ClO2 in drinking water as a result of routine use in the community water treatment process.
You are conflating very low background exposure to delibrate self-medication with a much larger dose. The latter act has a proven risk for no apparent gain, hence my doubts.
I'm not a doctor but have a background in biomedical research. Just to point out that there are countless fringe medical theories and therapies out there with varying degrees of anecdotal and scientific evidence backing them up. However it's quite telling that many claim the same benefits whilst instructing people to do the exact opposite things. Even the more promising ones (resveratrol and fructose toxicity are the ones I have actually spent time working on) eventually turned out to be nothing but wishful thinking and sometimes just bad science. I wish you the best of health but at the end of the day, what seems to have worked for you does not mean that it will work for everybody else.
Thank you for spending the time to write so far and for wishing me good health. I really appreciate it. I could tell about your background in your writing.
> what seems to have work for you does not mean that it will work for everybody else.
I agree with you on this. I just hope there was more funding or incentives for scientists studying this which, so far, has helped me and many people I know.
I didn't know anything about MMS before this thread, but I will point out that "don't eat that; it's poisonous" is a poor argument in a cancer debate, since the major treatment for cancer (chemotherapy) is intentional strong poisoning.
A company named Neuraltus Pharmaceuticals created a drug named NP001. NP001, a pH-adjusted IV formulation of purified sodium chlorite, is a novel molecule that regulates inflammation in vitro and in vivo.
It was used in a phase II clinical trial for ALS, and a subset of patients did not have any progression during the 6 month trial [0]. Something highly improbable.
Unfortunately this was not confirmed in a following phase III trial.
About the conspiratorial mindset, as you call it, for example, if YouTube censors “共匪” (“communist bandit”), then it must be a really bad idea, right? In which cases do you think it's reasonable not to trust YouTube blindly.
Hi - as the person you replied to noted, you were a cancer researcher. I recently had a much beloved dog lose her fight with cancer (specifically, she had mass cell tumors that started on her leg and grew). All of her oncologists (we spent close to ten thousand dollars keeping her as healthy and happy for as long as we could) kept telling us that mass cell tumors in dogs are "very nasty" and pretty much told us on the outset that even amputating her leg probably wouldn't save her. So my question is, what about mass cell tumors makes them nasty and, as a follow up question, why is it that the tumors became resistant to each line of treatment that we used? We went through I think 6 different drugs until we ran out of options, and then kept her on prednisone for about a year to keep the growth slowed down until she started showing signs of declining.
It's a conspiracy theory saying that we know natural and effective cures to cancer, but those are ignored or shammed by Big Pharma and scientific world because they are conspiring to instead produce drugs that are costly and require taking for long periods of time because thats more profitable to them.
I didn't mean that. Simply, pharmaceutical companies don't have incentives to invest in drugs that they won't profit from. Expired patent drugs come off first on that list.
1. We do attempt to attack cancers by reducing their available energy. That's why, at one point, a major field of research in cancer therapeutics was interfering with angiogenesis, because cancers will secrete messengers that help grow them dedicated (if crappy, low-quality) blood vessels. The issue with "starving" them more starkly is that they're very good at getting a share (e.g., forcing the body to supply them with blood vessels), so you're going to be hitting other labile tissues as fast or faster (skin, GI mucosa, blood and immune cells.)
Another way of targeting their rapid metabolism is pointing our therapy at cells with high replication rates. A number of our cancer therapeutics are aimed directly at cells that are currently replicating, which should selectively hit cancer cells (though again, it hits skin, GI mucosa, blood and immune cells, etc. because they're also high-turnover cells.)
We use methotrexate to interfere with DNA synthesis, thus reducing the rate of replication altogether (in cancer cells, as well as.... above).
The problem is, besides the dose-limiting toxicities of all of these things (because targeting metabolism hits all high-metabolism cells), is that cancer cells are really good at developing resistances. So, for instance, if you starve them of blood supply, they'll switch to anaerobic metabolism of glucose. If you starve them of glucose, well, you can't really - I'll discuss that below. If you give them methotrexate or other nasty drugs, they alter the cells' native drug-efflux pumps to target those drugs better and pump them right out of the cell. Cancer cells have a broken mechanism for protecting DNA - the result is really high rates of cell death among cancer cells, and also really rapid evolution.
In terms of starving cells of glucose: glucose is the least common denominator of cellular metabolism. It's the primary food source for the brain. Different cells have different receptors for absorbing it, with different levels of affinity. If you're running low, pretty much every cell in the body that can will kick up metabolic products to the liver to turn into glucose it can share with the bloodstream - because the best receptors in the bloodstream for picking up glucose belong to the brain. You'll starve, or poison, the brain long before you manage to starve out a cancer. (Yes, Ketone bodies are a thing, but that happens alongside your body mobilizing everything it can to feed the brain, not instead of.)
We also can't 'see' all the tumor. The way cancers actually develop is you have an abnormal cell A, which grows into a tiny nest. These are below detection in any practical clinical way, and we don't want to treat them because they're ridiculously common - your immune system wipes them up. If we tried to detect and treat them all, we'd kill everyone with side effects long before we prevented a fatal cancer.
Out of the bunches of these that develop and die, or develop and go permanently quiet, one gets active enough to start seeding tumor cells into the blood stream. Most of those cells will die, too, because blood is rough for cells not built to withstand it. Most of these are going to be undetectable in any way, and do nothing to people.
(Every time I say something is undetectable, I mean "Except for high precision laboratory experiments used to detect just such things").
Eventually a tiny pre-pre-tumor will start seeding cells into the blood stream that can survive the blood. These will get seeded effing everywhere. Most of these are permanently quiescent and do nothing, ever. They exist at the level of single cells - we can't see them. They don't do anything, metabolic activity very low, so we can't target them.
Once in a blue moon you get one seeded that is actually metabolically highly active. Or maybe it mutates into metabolic activity later. Most of those die.
Once in a blue moon, one of these will live enough to start replicating for real. Most of those get wiped out.
And once in a blue moon, they start replicating for real, and develop immune evasion, and you have something that becomes a cancer, maybe. Or it gets triggered by something external and becomes a cancer. There's a "seed and soil" element here. It'll often start seeding back into the blood stream.
By the time you have a detectable mass, your entire body has been seeded with these cells, most of them both un-image-able and un-selectively-treatable. Luckily, the overwhelming majority of these cells - lots of nines - won't do jack. Of the trillions that will seed your body, if we stimulate them just right, you might get a couple of new tumors, or none at all.
We know this because we learned that tumors benefit from circulating inflammatory markers early in modern oncology. When a surgeon took out a tumor, not infrequently, a patient would come in a year later with a new one or two that weren't previously detectable. We eventually learned that the inflammatory growth signals that come with surgical trauma can provoke an otherwise sleepy tumor cell into metabolic activity.
Which is a roundabout way of saying "cancers are more metabolically varied than the late, aggressive stage of the process we usually refer to as 'cancer' would suggest."
That being said, if you could inject something directly into the tumor (rather than the bloodstream would prioritize sending said poison pill glucose to the brain or liver) and take advantage of its metabolism, that would be great. We do kind of do that: we implant radioactive pellets directly, with the added benefit that we know it won't affect much tissue outside of the immediate area.
I hope my answer was actually useful in providing some biological context? I'm afraid I might have just word-vomited instead of being helpful.
> I hope my answer was actually useful in providing some biological context? I'm afraid I might have just word-vomited instead of being helpful.
I'm enjoying all your comments in this thread. You're knowledgeable and you're doing a good job of translating it into lay terms. I've had cancer and I'm a nerd, so I've read a fair bit about it. Everything you're saying fits well into my understanding, and you've given me some new things to look into.
This is fanatics thanks! The inflammation from tumor removal causing cancer cells to awaken is very interesting. I had a partial nephrectomy, so hypothetically my chances of reoccurrence is slightly higher since I had my tumor removed? But of course we couldn’t leave it in either. Is the staging have anything to do with how likely they are to wake up?
It's probably not meaningfully higher - this discovery was made a long time ago, and since then we've had a lot of research into which tumors it's really relevant to, and those tumors now get anti-inflammatory medication as a standard part of treatment to prevent just that from happening.
The staging is just ("just") a reflection of the primary cancer mass, which is really predictive of outcomes. It's generally not directly related to whether these sorts of satellite tumors form, since the above advances. It's mostly at this point a historical point of "this is part of how we figured out how cancer works," and ties into the rationale for some of the now-standard treatments.
"I hope my answer was actually useful in providing some biological context? "
Yes, it was!
"These are below detection in any practical clinical way, and we don't want to treat them because they're ridiculously common - your immune system wipes them up. If we tried to detect and treat them all, we'd kill everyone with side effects long before we prevented a fatal cancer."
I suppose it would help, if this would be more common knowledge. That cancer cells are very common and nothing to be afraid of.
Just that when things go very wrong, it becomes a problem. And that is mainly, when the immune system fails?
So I suspect the stress for the fear of getting cancer, might in some people lead to actual cancer, by lowering their immune system.
Could you agree to such a statement, or do you think it is far off?
I do wish people were more aware of how common pre-cancer cells are. Generally speaking, there are about eight major functional changes in the cell needed to go from 'cell' to 'cancer cell', and on average, each takes about a decade to occur. When I first learned about this at the age of 20, I already had a bunch of cells that were 2/8 of the way to cancer, essentially. (Not counting mutations I was already born with. Most of us are, which is why cancer is common before age 80.)
It's fair to say that it's a "failure of immunity," though it's a bit more varied than that. You might have started with a failure of the immune system, in the sense that something like autoimmune proliferative syndrome means cells that should be committing suicide aren't, and so eventually you have cancer. More common is a "normal" immune system, and a cancer cell lineage that evolves to be invisible to it.
Either way, it's fair to say that normal cells and cancer cells are divided by the fence of "immunity," and cancer doesn't happen until the cancer cells hop the fence or the fence falls down.
I suspect the fear -> cortisol -> immune suppression -> cancer pathway is probably, quantitatively, pretty small.
Stress does have negative effects on the immune system, in the broad sense, but granularly it gets more complicated. For instance, one of the key cells involved in keeping cancer at bay is the CD8+ cell. While total CD4/CD8 t-cell counts seem to trend down when cortisol trends up, CD8 T-cell counts actually trend up.
We know that Natural Killer T-cell activity drops in response to cortisol, in isolation, but that it has differing effects on NK cells in different organs. In some organs, it had no impact at all, due to shielding by other inflammatory signals.
It's probably true that there are some people who, if they didn't stress out about getting cancer, wouldn't have gotten cancer. I suspect that number is very, very, very low, though, and I'd certainly never tell a patient (or believe about a patient) "if they'd had different thoughts, they wouldn't have cancer."
I can't rule it out as never having happened. It's not physically impossible. But, compared to all of the other things that play a role in cancer development, it's probably not worth mentioning.
(I feel like I should clarify on the first paragraph: in short, every cell is somewhere on the continuum between 'normal cell' and 'cancer cell'. The only difference between the two is time. Like that Palahniuk quote, "On a long enough timeline, everyone you love is dead"? Well, "on a long enough timeline, every cell is a cancer cell.")
> on a long enough timeline, every cell is a cancer cell.
Not really true, except in the grandest sense (“humanity is the cancer of Earth”).
Which brings up a really interesting question - how can our reproductive system be so good at removing/restoring the effects of cancer & ageing? Why is sperm quality dropping with age but the effect resets after conception?
Okay, that's what I get for trying to be even slightly witty, username notwithstanding.
Some cells never divide, and so theoretically shouldn't become cancerous. They still happen though: myocardium tumors shouldn't happen, but hey, rhabdomyoma. In that case, it's more likely in youth / congenital, because it had to happen via inherited defect rather than one that accrued through cell replication in your lifetime. It is rare, though, and ridiculously rare in adults. Still, "on a long enough timeline...". I mean geeze, let a guy get a tiny bit poetic.
Other cells don't have DNA and don't reproduce, so they shouldn't be eligible (red blood cells.) They still fall into a grey area though: the RBC itself will be dead soon enough and never leave behind cancerous progeny. On the other hand, your bone marrow can absolutely lose its mind and pump out the equivalent of a red blood cell mass, a condition known as polycythemia. You can also have RBCs turn cancerous before they become fully mature and shed their DNA. The erythroblast stage - the late stage of RBC development, the last stage before it chucks its nucleus and becomes disposable - can develop into a leukemia.
Our reproductive system generally keeps its genetic payload cells in stasis for the lifetime, so it doesn't accrue replication errors, as well as sitting behind a protective wall (e.g., the Blood-Testis Barrier) similar to the one that protects the brain. Even in stasis, though, damage accrues - the age of the parent has a direct impact on the likelihood of various congenital disorders.
So, this is just a conceptual schema, and not a hard-and-fast rule. It was first published by Robert A. Weinberg in 2000 as "the six hallmarks of cancer", as an attempt to distill down everything we knew about cancer genesis into something we could understand as a model. He's considered the grand high poobah of oncogenetics. There've been people fretting at the details of his model since then, so it's grown a bit.
Also worth noting that this model was basically built on solid tumors. Liquid cancer (cancers of the blood - e.g., leukemia) have a different, more poorly studied path, though the broad brush-strokes seem to be the same.
The original model was:
-Evading apoptosis
-Self-sufficiency in growth signals
-Ignoring anti growth signals
-Autonomous, ongoing angiogenesis
-Tissue invasion
-Limitless replicative potential
The version that I learned in grad school was up to 8 hallmarks. Apparently it's evolved a bit more since then, and the most recent version being bandied about is:
-Evading apoptosis
-Self-sufficiency in growth signals
-Ignoring anti-growth signals
-Autonomous, ongoing angiogenesis
-Tissue invasion
-Limitless replicative potential
-Avoiding immune destruction
-Tumor-promoting inflammation
-Genome instability and mutation
-Deregulated cellular energy metabolism
Honestly, I'm not sure the ten hallmark model really adds anything - I'd argue that the four additions fall neatly under the old six. But whatever - it's just a model, and doesn't change the granular reality at all.
To summarize each of the hallmarks in brief:
(1) Evading Apoptosis. Cells have a number of mechanisms that basically say "something's off here, I should kill myself now."
For instance, when DNA repair enzymes get upregulated, so does p53 - if p53 tips over a key value, it starts setting off the suicide pathway. So, "too much DNA damage" = "cell offs itself rather than propagating damaged DNA." There are actually a bunch of proteins in the cell see-sawing here, in response to internal and external signals, and if the "kill yourself" signal tips the see-saw, the cell dies.
Pretty much any mutation in the cell suicide pathway predisposes to cancer. For instance, an extrinsic trigger of apoptosis is binding of what's called the FAS Ligand to the FAS Receptor (a big part of how immune cells regulate their own suicide, to prevent auto-immunity.) A mutation in FAS Ligand, or FAS Receptor, or anything downstream of them, will predispose to autoimmune disease and cancer.
Another one is the anti-apoptotic protein BCL-2, which you'll find overexpressed in something like half of all cancers.
Since cancer development triggers so many "kill me now!" signals, turning this pathway off is a hallmark of cancer development. The cancer will usually do so through a combination of over-expressing anti-apoptotic proteins, and under-expressing pro-apoptotic proteins.
Do we make use of this knowledge for therapy? Sure do. One therapy is a BCL-2 inhibitor, Venetoclax. Methotrexate, which slows down cell proliferation, also causes adenosine accumulation that can trigger apoptosis. These drugs have varied benefits: when you target the specific broken pathway in the cell, they're excellent (e.g., BCL-2 in CLL). Cancers are good at evolving around these therapies though, so they're not used as mono-therapy.
(2) Self sufficiency in growth signals. Normal cells don't just grow on a whim - they require signaling from cells around them and from distant parts of the body, to ensure things are kept regulated. Once a cell starts generating its own growth signals, though - like an army in revolt, giving its own orders - then you're on the path to cancer. This is one of the key mutations that gives rise to the "atavistic cell" description of cancer - they've thrown off their shackles, and become wild cells again! Well, not really - even wild cells are careful about when to expend the resources to proliferate. Bacteria commonly depend on their neighbors - using whats called quorum sensing molecules - to control their growth. Heedless, runaway growth is not the norm even in 'wild' cells.
(3) Ignoring anti-growth signals. Most everything in the cell is the process of see-saw balances: there are always signals pushing in each direction, compensating biochemical pathways, and shifting balances. Growth is no exception: how the cell acts is in response to a whole bunch of pro- and anti-growth signals, and most of the time it moves in the direction that they're pressured to by the consensus.
Well, if one of the hallmarks of cancer is like an army giving itself orders (independence from external growth signals), another is the active refusal to heed anti-growth signals (shutting down lines of communication with the Joint Chiefs of Staff). This may be because key anti-growth receptors are broken; it may be because something downstream of those receptors is broken. The key is, though, that between "I'll tell myself when to grow" and "I don't care what anyone else says to the contrary," the cell is now positioned to grow and grow and grow.
(4) Autonomous Angiogenesis.
Tissues need oxygen and nutrients and stuff. However, that stuff really only travels a tiny distance from the smallest blood vessels - capillaries - because it has to leave the capillaries via diffusion, and the time for something to travel by diffusion increases as the square of the distance. So, going 4mm will take 4x longer than going 2mm. Forget about feeding tissues 1cm away from a capillary - it's not happening. Usually, outside of embryogenesis, blood vessel construction is rare - it happens when a blood vessel is damaged, and it secretes growth signals to build a new vessel. (In fact, in a well regulated environment, this is often followed by signals to kill some of the new vessels, too - which is why a fresh scar is red and angry, but an old one is pale and avascular. The blood vessels that came in to supply immune cells and fibroblasts actually regress.)
So, anyway, here's our tumor - replicating like wild, if it can, not caring if it grows too far from a capillary. One of the consequences is rampant cell death. Tumors aren't healthy, they're usually riddled with dying cells. Another consequence is shifting to anaerobic metabolism - which, yay, don't need blood supply so much. But it's also massively less energy-efficient than oxygen, so any tumor cells that can make use of oxygen supply will tend to outreplicate those that can't.
So what happens? Almost inevitably, they start secreting stuff like VEGF (vascular endothelial growth factor) to grow their own blood vessels. These vessels are messy and leaky and prone to breaking, but they're so much better than nothing, and our tumor is off to the races.
Do we target angiogenesis in therapy? Yeah, there's a shit-ton of drugs that inhibit angiogenesis (you might have heard about bevacizumab a lot lately - we've also given it to Covid patients at high risk of hospitalization, since nothing in the body ever only has one effect).
I'll continue in another post; I'm not sure if HN has length limits.
Solid cells generally sit on a foundation called basement membrane. Tissue invasion means "fuck basement membrane, I'm cutting through it and getting into the sewer pipes (blood vessels) below!"
This actually has two consequences. One is that, well, it's not really cancer until it can escape its original confines - then it's just a pre-cancerous growth. There are a lot of cellular proliferative conditions that will get big, but never go anywhere (e.g., uterine fibromas). These can still cause problems due to displacement of normal tissues, but not of the "I'm all over the body and munching happily away" variety.
The other implication of this step, though, is another type of immortality. Being detached from the basement membrane is one of those cell suicide signals we discussed earlier. So if you can successfully invade the membrane and dig into tissue, the implication is "I'm no longer sensitive to the basement membrane's cell-death signals." These signals overlap and tie into the cell-suicide signals mentioned above. None of these things are completely walled off from the others.
(6) Limitless replicative potential.
Normal cells are limited in their ability to replicate. Every time they do, there is a bit of their DNA that degrades on the ends. In order to compensate, there's a little end-cap, like the plastic aglet on a shoelace, that is there to be sacrificed. Those are called telomeres. Cancers will develop runaway enzymes for restoring those telomeres, so that they never run out of runway for cell replication.
There are other mechanisms in there that make it more complicated, though - we know this because some creatures have much longer telomeres than we do, but not proportionately more cancer (rabbits, if memory serves.)
This also gives rise to some of the weirdness in cancer research. We need immortal cell lines to do standardized research (so everyone is using the same baseline), but by being immortal they are fundamentally abnormal. The HeLa (Henrietta Lacks) cell line of recent fame is one of these immortalized cell lines. (Worth noting: at least in my lab, it wasn't hard to immortalize a cell line if needed. HeLa was unique only in that it was used early enough to become ubiquitous and set a standard - not that there's anything otherwise noteworthy about that particular handful of cells. They're the USB of cells.)
(7) Avoiding immune destruction.
There's overlap between all of these categories. Some of the ways your immune system kills pre-cancer cells are the pathways we broke above: the immune system might trigger apoptosis directly or indirectly, for instance. A cell-killer (CD8+ cytotoxic cell) will attack with an enzyme called 'granzyme', that explicitly tries to trigger apoptosis!
But there are other ways for the immune system to kill, and to be evaded. For instance, cells all express what's called "MHC 1". It's like the inspection sticker on your car. It take samples of intracellular proteins and shoves them up onto the cell surface for inspection by the immune system. If they're unusual, the immune system binds to them and kills the cell. So, not surprisingly, there are some cancers that downregulate MHC 1 - parking your car in your driveway so no one sees the expired sticker. This is common, I believe, in lung cancers. You can also see defects in the machinery that gets proteins to MHC 1; you can increase expression of "come hither" signals for immune suppressing cells (e.g., Regulatory T Cells, and Myeloid-derived suppressor cells); or secretion of immune suppressing molecules directly (e.g., TGF-Beta, IL-10, and VEGF). If VEGF sounds familiar, I should point out it's the signal for growing new blood vessels above.
(That's not a coincidence. Healing a wound requires quieting the inflammation that preceded the healing.)
New research in cancer vaccines is focusing on how to either restore the immunogenic environment, or to use alternative pathways. For instance, the toll-like receptor pathway doesn't usually play much of a role in developing cancer, so it's usually intact - so one of the new strategies that's being worked on is how to activate that pathway in response to cancers. And, we have drugs that target some of the elements here! For instance, those T-Regs express the cell surface marker CD25, which we can hit with a drug called daclizumab (I hope I got that spelled right - small molecule and monoclonal names are all gibberish.)
(8) Tumor-Promoting Inflammation. This wasn't a separate hallmark when I was a wee baby: the inflammatory signals promote cell proliferation, they can make blood vessels leaky, they can make blood vessels dilate (the combination means lots of yummy blood to feed a tumor). Inflammation also brings in lots of tumor-killing signals. "Tumor-promoting inflammation" is basically "everything I described above." So, I don't know, maybe something unique has been found here over time that I missed out on as the field evolved? Or not - all of these have grey areas of overlap.
(9) Genome instability and mutation.
Cancer cells, by virtue of shedding their DNA-protecting mechanism (cell death if the DNA is damaged too much) and going into rapid division, break the absolute shit out of their DNA. Not just the run-of-the-mill "oh, mutations accrue" type of breakage. I mean chromosomes are breaking and reattaching and breaking again, centromeres are all over the place, it's a shit show. This is a normal karyotype (image of the chromosomes as a whole): https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.scienc...
This "genome instability" doesn't just allow for rapid evolution - the fact that it can exist without the cell suiciding is a great big flag
that this cell has very serious immortality mechanisms in play already.
(10) Deregulated cellular energy metabolism.
All of the stuff regulated above? It regulates, and is regulated by, cellular energy metabolism (which also feeds into various other type of macromolecule metabolisms - so when energy is dysregulated, it's like saying "our entire supply-side market is broken.") Which means dysregulated growth, dysregulated proliferation, etc. This is also a really core pathway - you can't fuck with such elemental life-or-death metabolic pathways without breaking stuff or killing stuff. By the time a cell can dysregulate these pathways (excess free radical generation by way of energy pathways is one of those cell suicide triggers, for instance), it's already shed a lot of its suicide signals and it's just burning through energy without heed for the tissues around it.
I appreciate your comprehensive answer, it's very helpful.
Question:
> "you'll starve, or poison, the brain long before you manage to starve out a cancer. (Yes, Ketone bodies are a thing, but that happens alongside your body mobilizing everything it can to feed the brain, not instead of.)"
Layman here, but my understanding is that depriving the body of the ability to replenish glycogen stores that are normally used for energy forces the body to metabolize fat in order to produce ketones, which in a ketogenic state, the brain is entirely fine utilizing as a primary energy source. Thus, if in a ketogenic state (or on a strict ketogenic diet), the body isn't being starved, just consuming stored energy reserves.
You've got it essentially correct, it's just that every metabolic pathway is in a dynamic equilibrium. So let's say you do deprive the body of fresh glucose intake. While liver is turning fat into ketone bodies, and brain and skeletal muscle are digesting those ketone bodies, at the same time that TCA cycle that is now getting fed ketone bodies is going to push back upstream to tilt 'eat sugar' (glycolysis) a little bit more towards 'make sugar' (gluconeogenesis); meanwhile, other ketone bodies (dihydroxyacetone) are going to plug right into the gluconeogenic pathway.
The body will be making glucose where it can, because, if I recall correctly, red blood cells can't make use of ketone bodies, full stop. Some level of production must be maintained.
Which, in the body's parlance, is 'starvation'. If red blood cells are going hungry, from the body's perspective, there's a serious problem. But that's part of the difference between true ketosis and a ketogenic diet - the latter continues glucose intake, with a preference towards stimulating ketogenesis. The former is "oh fuck where's the glucose why can't I use the glucose aaaaaah!"
I gotta go refresh this now - you're painfully reminding me of how long it's been since I reviewed biochem.
> Making the glucose the patient intakes mildly radioactive
The carbon and oxygen in glucose used as fuel doesn't stay in the cell - it becomes lactic acid (or carbon dioxide and water), which leaves the cell.
You could make a weaponised version of something which does get retained in the cancer cell. For example, nucleosides, which are the raw material for DNA, and which are needed in volume to support cancer cells' rapid proliferation. These drugs are called nucleoside analogues, and are used to treat cancer and viruses:
If cancer cells have high metabolic requirements, couldn't you attack them by:...
The keto diet is actually recommended for certain types of cancer patients for this reason. While almost all human body cells can adjust to using ketones, most types of cancer cells cannot.
[1] Say replacing the hydrogens in glucose with tritium
That's part of the problem. Think you can come up with a synthesis of glucose that replaces the nonlabile hydrogens with tritium, is doable on the days scale, repurifiable for human consumption and mass producable on-site at a hospital?
I'd be willing to have a crack at this if I thought it could help (my background is in nuclear methods for materials characterisation). But I've a feeling that the difference in uptake between cancerous and normal tissue might not be large enough to make this especially useful. Fluorine-18 labelled glucose is used in PET imaging, but not for treatment as far as I'm aware. On the other hand, if a compound can be found that is more selective for the cancer in question, making it radioactive may offer a further improvement.
Isotope labeling for imaging requires only a low isotope purity. One radioactive glucose in a vast sea of normal glucose is just fine, because as I'm sure you know the energies of the emitted particles make a very distinct marker.
>Not so radioactive that the person is harmed but radioactive enough to pack an extra punch to the metabolically starved, and therefore stressed, cancer cells (who are drawing more of the glucose to themselves).
Tritium will be transferred to proteins and retained in the body. A low-calorie diet won't help: when the glucose enters the citric acid cycle, the 3H will end up everywhere. 18FDG, used for PET, is also concentrated in the kidneys and bladder, ruling it out for therapy. If it were that easy to find something uptaken only by tumors, we'd be using it.
In brachytherapy, we do something like this, except we put a solid radiation source inside the tumor. Nonetheless, the treatment has serious side effects.
The high metabolic rate is used. Some forms of chemotherapy kill cells that replicate quickly. That's why hair falls out and patients puke - the gut lining replicates quickly.
At least that's my understanding. I'm not in the field.
Low-carb is a thing/fad/potentially useful practice among patients.
As to Radioactivity, I’m not sure if your model would work: higher usage does not necessarily mean “more contact with”. Does the fish that drinks more have more exposure to water than his friend?
That said, radioactivity is obviously used, because cells at the proliferation stage are specifically susceptible to it. The same is true for most chemotherapy, I. e. they target the mechanisms of cell division.
> It doesn't produce any alternative lines for thinking about treatment, causality, etc.
The whole "genes that shouldn't be on being switched on" thing made me think about David Sinclair's work on aging, and his information theory of aging.
Has anyone been really looking into ways to avoid damaging (or ways to repair) epigenetic information as a potential solution to cancer?
Couldn't agree more. I actually wrote a reply along these lines then decided I should get some work done and dropped it.
>"Cannot help but switch to previous single-celled metabolism"
This line itself should immediately give anyone with a molecular bio line a pause. Molecules, cells and other small chemical phenomena are not humans. They do not act with intent.
Personifying these machines and systems may be helpful to make a system relatable, but it is a toy model, not an explanatory one.
Thanks for the detailed info. I had read once that some large animals (e.g. blue whales) have surprisingly little cancer.. any idea why this is the case? Or is it just the rarity of us testing large animals for cancer?
> There is a relatively new theory saying that malignant, metastatic cancer cells behave like single cell organisms,
This is the track they are on, but given how shortlived they are, they never get the chance to do much evolution. They only have time to learn a few tricks. Simple things like turning stuff of or up/downregulating existing systems. It's a strange step to "cannot help but switch to the previous single-celled metabolism, very inefficient compared to ours".
> given how shortlived they are, they never get the chance to do much evolution
There is a very rare category of cancers for which this is not true, clonally transmissible cancers[1]. They can move from individual to individual like other pathogens. One example is the devil facial tumor disease[2] that has killed around 95% of Tasmanian devils.
I'm no biologist, but I'd be surprised if this is true.
Genes which are essential the the function of an organism are well conserved relative to silenced genes over long time spans.
This is because mutations happen randomly, and mutations to essential genes in the germline tend to get weeded out, while mutations to silenced genes can get corrupted without affecting the fitness of the offspring. This theory, from the way you've stated it, would require preservation of inactive genes for hundreds of millions of years, only to spring back to action in cancer cells.
You're assuming that the set of genes that produce multicellular life are largely disjoint from those that produce unicellular life, and that is unlikely to be the case. Much more likely, multicellular life is an incremental set of changes layered on top of unicellular life, and so the only thing required to revert from multicellular back to unicellular is a breakdown in that higher-layer functionality.
If you're not already familiar with them, you might want to look up HeLa cells:
> You're assuming that the set of genes that produce multicellular life are largely disjoint from those that produce unicellular life,
I assume no such thing.
I've read (but can't cite) that roughly 90% of our genes are related to construction and maintenance of the cell itself, and only about 10% are related to higher order organization. Just as it has been said that something like humans and tomatoes have 50% of our genomes in common, there is a significant but smaller percent that we have in common with single-celled life forms.
"This theory, from the way you've stated it, would require preservation of inactive genes for hundreds of millions of years, only to spring back to action in cancer cells."
This is only true if the genes for being single-celled are inactive in multi-celled creatures and would need to be re-actived to revert to being single-celled. But this is not the case. Milti-cellularity is a functional layer built on top of single-cellularity, so to revert to being single-celled you have to deactivate currently active genes, not activate inactive ones.
Well, that is why I linked to NIH rather than one scientist's blog.
Myers is very outspoken in his rejection of the idea, but even as an amateur I can see rhetoric sleights of hand in his argumentation. An example:
These “layers” don’t exist! When my car malfunctions, I don’t get a horse
Bad comparison, a car did not evolve from a horse, there is no mechanism for it to have a previous "horse layer".
Myers seems to hate the idea so much and return to it so often and with so many damnations and so few citations that it actually decreases his credibility in my eyes.
Well I wouldn't say the multicellular system is reverting to a single older cell phase per say. Rather it needs NAD+ so it optimizes for that. The cells also lose adhesion and then migrate so clearly there's some "programming exception" not being caught. I view the cell as a bunch of copy paste code that's had some degree of refactoring applied so there are different programs and control systems in operation at any given time. Sometimes these get activated or not repressed erroneously, sometimes the source code gets scrambled.
Yeah, there isn't really any science to back it up.
> and the original genes might carry on within our DNA until today
Luckily we don't need to resort to "might". Since the advent of genome sequencing we can just go ahead and take a look!
E.g. yeast (your standard single-celled organism) posesses ~6000 genes of which ~23% (= 1380 genes) are similar in function to those of humans. Of those genes most of them have been severely mutated, on average sharing 32% sequence similarity, which is a world of difference in terms of protein functionality.
The few highly preserved genes that remain are core parts of all eucaryotic life (ribosomes, proteins for amino acid metabolism, etc.) and are some of the most studied genes (regarding cancer and in general).
Suggesting that there are some genes hiding in there and have been overlooked due to narrow-mindedness of the whole life science community is a bit naive.
So someone left in a bunch of legacy code and nobody knows which combination of feature flags fully turns it off? At least if we cure cancer we can use whatever we learned to make programming a little easier.
"The findings suggest that drugs that force cancer cells to switch back to aerobic respiration instead of fermentation could offer a possible way to treat tumors. Drugs that inhibit NAD+ production could also have a beneficial effect, the researchers say."
And hopefully that's a path to follow that will help treat/cure some types of cance? This all just barely makes sense to me, but my first question was "Does this help beat cancer in a new way?" and I guess the answer is... maybe?
So tempting to go with analogies we are familiar with.