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Researchers Block HIV Infection In Monkeys With Artificial Protein

An anonymous reader writes: Immunologists have developed a synthetic molecule that's able to attach to HIV and prevent it from interacting with healthy cells. "HIV infects white blood cells by sequentially attaching to two receptors on their surfaces. First, HIV's own surface protein, gp120, docks on the cell's CD4 receptor. This attachment twists gp120 such that it exposes a region on the virus that can attach to the second cellular receptor, CCR5. The new construct combines a piece of CD4 with a smidgen of CCR5 and attaches both receptors to a piece of an antibody. In essence, the AIDS virus locks onto the construct, dubbed eCD4-Ig, as though it were attaching to a cell and thus is neutralized." The new compound was tested in monkeys. After successively higher injections of HIV, all four monkeys who received the compound beforehand stayed from free infection. Any potential medical treatment is still a ways off — the researchers plan more trials in monkeys before involving humans in the testing.

56 of 96 comments (clear)

  1. Re:first post motherfuckers by ionymous · · Score: 1

    anyone see where my pen is?
    Oh! There it is! thanks!

  2. Best news I've heard all day by seven+of+five · · Score: 5, Funny

    You've no idea what a pain it is to get a monkey to use a condom.

    1. Re:Best news I've heard all day by Anonymous Coward · · Score: 1

      You've no idea what a pain it is to get a monkey to use a condom.

      Why do you say that? Do they go Ape when you ask or something?

    2. Re:Best news I've heard all day by LifesABeach · · Score: 1

      And here I was thinking the study had been conducted in the halls of congress; now I can not get the picture of a primate in the halls of congress walking around with a condom on.

    3. Re:Best news I've heard all day by penguinoid · · Score: 1

      I've heard toucans have really big peckers.

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    4. Re:Best news I've heard all day by slashdice · · Score: 1

      haha, but what about penguins?

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  3. Re:Cancer just doesn't have that "it" factor!! by sribe · · Score: 4, Informative

    I just wish half as much effort had been put into fighting cancer as has been put into fighting AIDS over the last three decades.

    And what exactly makes you think that is NOT the case? Oh, wait, I see, you're a homophobic idiot who just assumes that because you see actors on TV talking about AIDS, that somehow there's no money being spent on cancer research anymore. You really could not be more wrong if you tried.

  4. Re:Monkeys With Artificial Protein by Anonymous Coward · · Score: 1

    http://i.imgur.com/yLRORhT.gif

  5. Re:Cancer just doesn't have that "it" factor!! by AmiMoJo · · Score: 5, Informative

    AIDS is a lot easier to beat than cancer, because cancer is actually a whole range of conditions that are caused by different things and need different treatments.

    --
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  6. Not really that newsworthy by Mortiss · · Score: 3, Interesting

    This type of compounds (HIV fusion inhibitors) is already well known and available on the market e.g. Enfuvirtide

    The only hope here is that this inhibitor will be cheaper and perform better in humans than already available ones. However, according to FA, these type of experiments are still way off..

  7. Re:Cancer just doesn't have that "it" factor!! by ArmoredDragon · · Score: 1

    And here I thought AIDS was too retro for contemporary artists.

  8. Re:Profit by AmiMoJo · · Score: 2

    I wonder if there is really much money to be made from a cure for AIDS. I mean, infection rates in developed countries are fairly low and protection is widely available and used. Western countries would probably try to eradicate it entirely once a cure was found.

    The big growth areas are where Catholicism and poverty is preventing people taking action to prevent the spread, but those areas are also unlikely to be able to afford to pay much for a cure.

    --
    const int one = 65536; (Silvermoon, Texture.cs)
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  9. Likely not. by emil · · Score: 1

    This technique will likely be effective against virons in blood plasma, but it will do precisely nothing to a quiescent provirus, so an infected individual will retain infection reservoirs. Unless the active protein can cross the blood-brain barrier, brain infection will also continue and will still lead to accelerated cognitive decline and aids-related dementia. Assuming that it works, this is a godsend for effective control, but a cure it likely is not. A cure will only be accomplished when the silent reservoirs can be coaxed into activity and the host cells containing the provirus are destroyed.

    1. Re:Likely not. by SydShamino · · Score: 1

      You're correct that this doesn't sound like a cure. On the other hand, it might be both a very effective vaccine for the uninfected, and a reliable treatment for those infected. (This depends mostly on HIV's ability to mutate these receptors into something that can reject the drug but still connect to the target cells.) Even if a vaccine isn't a cure, it can lead to eradication of the disease. The smallpox vaccine wasn't a cure either, for example, but with sufficient coverage it was quite effective.

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  10. Re:Cancer just doesn't have that "it" factor!! by rogoshen1 · · Score: 3, Informative

    Yep, while AIDS is preventable; it still kills a huge number of people in Africa. In the grand scheme of things AIDS deaths in the west are a drop in the bucket by comparison.

    Should research not be done in an effort to help that situation, just because some gays in the west die from the same diesease?

    Blind, or evil -- take your pick.

  11. Re:Cancer just doesn't have that "it" factor!! by jbarone · · Score: 2

    A whole lot of cancers are preventable, or at least the odds of getting them can be substantially reduced. But they require lifestyle changes, like getting more exercise and eating less and healthier, that affluent westerners don't like making. Much easier to heap blame on others for not changing THEIR lifestyles in a way to prevent diseases, while we rely on pharmaceutical corporations to find cures to the diseases that affect us.

  12. Re:Cancer just doesn't have that "it" factor!! by MightyYar · · Score: 2

    It makes me so angry all I see is pink.

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  13. Re:Cancer just doesn't have that "it" factor!! by jellomizer · · Score: 2

    While it is one one most preventable in terms it, can be controlled by voluntary actions. However these actions are in societies taboo areas. So it is difficult to say to propose the use of condoms to people in a society where they are told not to have premarital sex. So by having such items shows that you are guilty of diverting from societies expectation.

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  14. A biological "race" condition? by TomR+teh+Pirate · · Score: 2

    My understanding of HIV is that when it infects human cells, it hijacks the tRNA (iirc) so that the human cells continue producing more HIV viruses. With the article describing synthetic antibodies binding to HIV, the virus is unable to infect human cells. So this would seem like a race condition where the antibody needs to get to the HIV *before* HIV has a chance to infect a human cell. How can this happen reliably?

    1. Re:A biological "race" condition? by Gilgaron · · Score: 1

      You'd just have to stay on the treatment until all of your already infected cells die.

    2. Re:A biological "race" condition? by smellsofbikes · · Score: 1

      My understanding of HIV is that when it infects human cells, it hijacks the tRNA (iirc) so that the human cells continue producing more HIV viruses. With the article describing synthetic antibodies binding to HIV, the virus is unable to infect human cells. So this would seem like a race condition where the antibody needs to get to the HIV *before* HIV has a chance to infect a human cell. How can this happen reliably?

      Mostly through concentration: making sure there are 100x or more antibodies against HIV present than the cells HIV is targeting.
      But it's also helped by binding affinity. When a receptor and a substrate bind, it's generally reversible -- they can join or separate, and there is a measurable equilibrium between the bound and unbound states, which is a function of concentration of both receptor and substrate, and a constant that reflects how well they actually stick together. Generally, antibodies are _vastly_ better at sticking to things because they're designed to be. (Okay, the 'designed to be' is not actually true but for the purposes of this, it's an okay approximation) So if your antibody/HIV binding affinity is 100x better than the HIV/cell binding affinity, and you have 100x more antibodies than target cells, the number of viral/cell bindings is going to be much lower than the number of antibody/viral bindings.

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  15. Re:Cancer just doesn't have that "it" factor!! by arkane1234 · · Score: 1

    THANK you. There are so many people I hear say stuff like "Oh, cancer has already been cured, they're just holding the vaccine back from us" or "I'm waiting for the cancer pill to come out".

    About as bright as waiting for the pill to stop death.

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  16. Re:Cancer just doesn't have that "it" factor!! by king+neckbeard · · Score: 1

    HIV is infectious and cancer is not (HPV is though).. HIV has only one cause, while cancer takes countless forms with countless causes, and factors that might decrease the risk of one may increase the risk of another. Fighting cancer is like fighting death.

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  17. Re:why? by codeButcher · · Score: 2

    Yeah, or they could test on politicians. Lab staff does not tend to get so attached to them, but otherwise not much difference.

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  18. Re:Derp by arkane1234 · · Score: 1

    Yes, Derp is right. Please stop.

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  19. Re:why? by arkane1234 · · Score: 1

    Like, the entire human race, yes.
    Apes can't sue, though.

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  20. Re:Cancer just doesn't have that "it" factor!! by bobbied · · Score: 4, Insightful

    What a troll... Who cares?

    Look, I don't care what the Hollywood elites want to throw their PR machines onto, it's usually bogus from them anyway. For the most part it's about the show, the PR the "look at me!" mind set with them. If their efforts manage to actually *help* somebody, I'm totally happy for everybody involved, knock yourselves out, raise money enjoying rubber chicken at $10,000/plate or recording PSA's for free.

    Just remember that all this hoopla is only really about 2 things. 1. Public Relations and keeping your face in front of the paps so your photo shows up more often to keep your prospective fan base alive between your actual paying gigs... 2. For some, a secondary point is to assuage their feelings of guilt for being so affluent and living in such opulent surroundings. They tell themselves they ARE good people, after all they did all this AIDS/Cancer/Feed the Children/SPCA and PETA stuff for free..

    Be happy anytime good comes out of something and stop complaining that their issue of the day is the wrong one in your eyes. Be happy even if their motives for doing good are no good. Just be happy that good is being done and let the rest go. Then go out and do what YOU think is right...

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  21. How does one "Stayed from Free Infection" by dbrossard · · Score: 1

    I can understand Freeing a Stayed Infection, or even Staying Infection from Freedom. But what the heck is this?

  22. Re:Cancer just doesn't have that "it" factor!! by Anonymous Coward · · Score: 1

    I wouldn't say it's easier... The mutation rate of HIV is absolutely incredible. That's why they have to give 3 drugs or more at a time just to keep it in control. While there have been several people who've been cured of "cancer" (being an umbrella term, thank you for point that out), I've only heard of 1 person ever being cured of HIV ("Berlin patient" Timothy Ray Brown). Lots of people have undergone the bone marrow transplant and being free of the disease for years, but had a relapse later.

  23. Re:Cancer just doesn't have that "it" factor!! by SydShamino · · Score: 3, Interesting

    More recent HIV treatments target portions of the virus that mutate slowly, and are moreover unlikely to be able to mutate more quickly. These have significantly higher chances of being a "cure" compared to the older cocktails to which you refer. Unfortunately it did take 20 years of AIDs research to figure this out and have the knowledge and technology to develop these techniques, but I think a very reliable vaccine will be readily available by the end of the decade, and a cure 5-10 years after that.

    --
    It doesn't hurt to be nice.
  24. Re:Cancer just doesn't have that "it" factor!! by pz · · Score: 4, Informative

    The biggest contribution from the massive levels of research on AIDS is not curing the disease. That will be wonderful when, and if, it happens. The biggest contribution will be that, as a result of trying to cure AIDS, we have learned immense, really truly immense, amounts about the immune system and it's incredible intricacies.

    And, guess what? Ultimately, it is the immune system that keeps your body free of cancer. Cancers happen frequently in your body, and the immune system beats them down. When it fails at that for some reason, only then does clinical disease happen. I've heard it said that most people have 6 or so small cancers in their bodies at any given time, all being properly managed by the immune system.

    Understanding the immune system, because we have been trying to cure a disease of the immune system, will eventually do more good for human health than any other single effort since the invention of antibiotics, with the possible exception of magnetic resonance imaging.

    But let's look at the GP's assertion about money. The National Cancer Institute's budget appropriation for FY15 was $4.9B. They're the part of the NIH that sponsors cancer research. The National Institute of Allergy and Infections Diseases, the NIH that is charged with fighting AIDS, had $4.3B appropriated for FY15. Even if we assumed that the entire NIAID budget went to AIDS (and it does not), the NCI has a bigger budget. So the GP is just flat out wrong with his initial assertion: much less research effort in the form of NIH extramural support is spent on AIDS than on cancer.

    --

    Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
  25. Re:Cancer just doesn't have that "it" factor!! by Em+Adespoton · · Score: 1

    THANK you. There are so many people I hear say stuff like "Oh, cancer has already been cured, they're just holding the vaccine back from us" or "I'm waiting for the cancer pill to come out".

    About as bright as waiting for the pill to stop death.

    Oh, there's all sorts of solutions to stop death. They're all rather permanent however.

    But yeah; Cancer is a description of a process, not an actual disease. I'd think that after so many decades of cancer awareness campaigns, people would get this. Cancer is basically about cells replicating in an unregulated manner. The CAUSE for this depends on what's actually wrong. Finding a cure for cancer is like finding a cure for headaches -- the problem isn't the headache (which kind?) but the process that is causing the biofeedback in the first place.

    And yeah; Lymphoma all by itself probably has got as much press and research over the past two decades as HIV (yeah; AIDS isn't a disease either; it -- again -- is a descrpition of a biological state).

  26. Re:why? by Em+Adespoton · · Score: 1

    Why do they use monkeys for this experiment? Aren't there plenty of homos around?

    Homo Habilus is dead already
    Homo Erectus is also dead.
    Homo Sapiens is long gone
    Homo Sapiens Sapiens is still hanging on....

    But why not try it on Homo Milk?

    Thanks, but I think Rhesus monkeys and Bonobos are probably better bets for now. Pigs and rats would also be decent contenders for some tests, but not others.

  27. Re:Cancer just doesn't have that "it" factor!! by Anonymous Coward · · Score: 3, Interesting

    Hodgkin's Lymphoma is actually an outlier and a really useful example.

    Hodgkin's is caused by a very specific mutation. Relatively early on, they realised that if you can poison the mutated cells without killing the patient, they get better. And if you're lucky, they don't just get better, they stay better, it's a bona fide cure.

    This same idea (just kill the mutants) seems applicable to a lot of cancers, but Hodgkin's stands out because

    1. Lots of young people get it. We don't know exactly why, but men in their 20s get it a lot (compared to say, lung cancer or other types of cancer, which mostly old people get). This means your cure has a remarkable effect. Old people were going to die soon anyway, but a 25 year old man cured of Hodgkins may well live 40-50 more years. So you can be 100% sure it's working.

    2. One very specific cell that scientists already knew existed has one fairly obvious and easy to understand defect. They didn't know why yet, but the cells look all wrong under a microscope. Cured patients, and normal people who aren't sick don't have the characteristic cells. So if something kills those cells, but not the patient, it's a possible cure.

    There is a downside to all this. We've been curing Hodgkin's for longer than we've done proper scientific medicine. The people who invented a cure didn't run a double blind trial to see how well it worked. They tried it, cured some people and went "Good work, time to go home". So today we have NO CLUE how bad Hodgkin's is exactly. If you're untreated at say, Stage IIb, can you expect to die in a year? Two years? Five years? We really don't know. Some people refuse treatment, and those tend to die horrible deaths a few years later, riddled with cancer and other problems, but not enough of them exist to have any confidence in an estimate and they're crazy people who avoid doctors, so who knows if it's a bad for normal people who just can't get cancer drugs.

    Because we're sure it works it would be terribly unethical to run a trial now. You'd be condemning half the trial participants to death, just to prove a point! So we will probably never be sure.

  28. Monkeys don't get HIV, they get SIV or SHIV by VitrosChemistryAnaly · · Score: 1

    I'm amazed that TFS says HIV as well as the first link. TFNA (The Fucking Nature Article) title is "AAV-expressed eCD4-Ig provides durable protection from multiple SHIV challenges". Wow, SHIV is right there in the title. Humans can be infected with "human immunodeficiency virus". Simians can be infected with "simian immunodeficiency virus".

    Additionally, plenty of "monkeys" get SIV and don't become symptomatic because they're natural hosts. Rhesus macaques (as stated in the Nature article), however, are not natural hosts and do become symptomatic. Just using the over-arching term "monkey" is ridiculous for a "science" blog.

    --
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    1. Re:Monkeys don't get HIV, they get SIV or SHIV by VitrosChemistryAnaly · · Score: 1

      Um, SHIV is a man-made construct. It's SIV with the envelope coding region from HIV.

      --
      "It's a tarp!" -- Dyslexic Admiral Ackbar
  29. Re:Cancer just doesn't have that "it" factor!! by Dragonslicer · · Score: 1

    You missed that episode of South Park, didn't you?

  30. Re:Cancer just doesn't have that "it" factor!! by Anonymous Coward · · Score: 1

    A whole lot of cancers are preventable, or at least the odds of getting them can be substantially reduced. But they require lifestyle changes, like getting more exercise and eating less and healthier, that affluent westerners don't like making. Much easier to heap blame on others for not changing THEIR lifestyles in a way to prevent diseases, while we rely on pharmaceutical corporations to find cures to the diseases that affect us.

    You mean once we convince our body not to mutate a cell during the normal cell replication process?

  31. Re:That's some good news by Anonymous Coward · · Score: 1

    Approximately 25% of straight people have had anal sex, compared to 60% of gay males.

    But since only about 5% of the population is gay, that means there's almost 10 times the number of straight couples having anal sex as gay couples.

  32. Could be a very effective treatment by PeterM+from+Berkeley · · Score: 2

    If you can cause the protein to be generated in the blood, why not also treat cells on the brain side of the blood-brain barrier as well to produce the protein and so protect the brain?

    If you can do that, you can halt transmission to new people, and halt progression of the disease on both sides of the blood-brain barrier, it's about as close to a cure as could be achieved without actually destroying all the quiescent viruses.

    Heck, it might actually cause less damage to the host than destroying all the quiescent viruses--the host cells are still sort of functional, but if you killed them all, their functions would fail completely.

    See for example the antiviral treatment in research, which causes infected cells to die:
    http://en.wikipedia.org/wiki/D...

    A worry with this treatment is that many nerve cells are infected with herpesvirus in some people, and simply taking these cells out may result in far more damage than desired. Better to leave infected cells intact and enforce dormancy, which protects hosts and prevents spread.

    --PeterM

    --PM

  33. Re:Cancer just doesn't have that "it" factor!! by Anonymous Coward · · Score: 1

    Actually, you're wrong. Sure not everyone who is clinically diagnosed with cancer had a choice, but more research every day shows how destabilizing your body's immune system is often a huge factor in the development of cancer that requires medical intervention. Take smoking as an example of one choice people make that often results in multiple forms of cancer. Another is diet. The foods and quantities that Americans consume contribute significantly to stomach, colon, or rectal cancers. I could go on and on because the substantial growth in cancer rates seem to be tied to many choices we as a species have made over the decades.

    Oh, and for the record, sexuality isn't a choice, but unsafe sex is and heterosexuals are just as guilty of it as homosexuals.

  34. Of course they stayed by sacrilicious · · Score: 1

    all four monkeys who received the compound beforehand stayed from free infection

    "Come for the injection, stay from free infection!!"

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  35. Re:Cancer just doesn't have that "it" factor!! by micahraleigh · · Score: 1

    Ad hominem-ing your way through the slashdot echo chamber I see.

    The other guy was a lot more daring than you.

  36. Re:Cancer just doesn't have that "it" factor!! by sribe · · Score: 1

    I could go on and on because the substantial growth in cancer rates...

    Good post, except for that bullshit that people so like to repeat. There is substantial decline, not growth, in cancer rates. This has been true for decades.

  37. Re:Cancer just doesn't have that "it" factor!! by sribe · · Score: 2

    People don't choose to get cancer. AIDS, however, is almost completely voluntary. Nice job, throwing slurs at dissenters, though. That's the way to show tolerance! :)

    1) Many people in the west voluntarily choose to engage in behaviors which greatly increase their chances of getting cancer. So, in developed societies, much cancer is voluntary according to your definition. Meanwhile, in Africa, many women have no choice whatsoever about being forced into activities from which they contract AIDS, and their children are certainly not born with it voluntarily.

    2) First off, the basic point the "dissenter" made was completely incorrect, there is not so vastly more research effort going to AIDS than there is to cancer and there is no factual basis that would lead one to such a conclusion, it was purely an unfounded assertion. Second off, my supposed "slur" was nothing more than reading what was obvious from the derogatory way he (yes, he, that too is obvious) referred to gays and those who advocate for their causes.

  38. Re:Cancer just doesn't have that "it" factor!! by sribe · · Score: 1

    Ad hominem-ing your way through the slashdot echo chamber I see.

    Nope. It is crystal clear that the poster is severely homophobic. Maybe you should read it again, carefully, and note the unfounded assertion based purely in bias, the deprecation of the suffering of a certain segment, the derogatory references to those who support them, and so on. The post was sickeningly vile.

  39. Re:why? by Culture20 · · Score: 1

    Apes can't sue, though.

    Humans can. Humans are great apes.

  40. Re:Cancer just doesn't have that "it" factor!! by DrSlinky · · Score: 1

    I just wish half as much effort had been put into fighting cancer as has been put into fighting AIDS over the last three decades. But then, cancer doesn't have every actor in Hollywood raising money for it, or treating it like the ultimate cause celeb because they have some gay friends. Even now that AIDS is completely survivable with drugs, every arrogant Hollywood asshole is still supporting AIDS charities at the expense of much more deadly diseases.

    Then why the fuck is half the shit in my my grocery cart colored pink, for Breast Cancer Awareness?

  41. Add it to the antivirals toolbox by __aaltlg1547 · · Score: 1

    We already have drugs that work pretty much the same way. This is just another of the same sort that can go in our toolchest.

    But we really need a vaccine.

  42. To take your point one step further... by mmell · · Score: 1

    Research into HIV and AIDS has occurred at a time when research on genetics is making discoveries at a breakneck pace. Combining these events has resulted in the discovery or creation of techniques in virology, immunology and epidemiology. Even if I knew nobody with HIV or AIDS, and even if those who had the infection were completely isolated from me I should consider myself the beneficiary of the knowledge and technology we've gained by working on vaccines, treatments and cures for this disease.

  43. Re:why? by dave420 · · Score: 1

    Let's not get carried away - they're pretty good apes. Did I say they? I meant we. Shit. Ook.

  44. Re:why? by dave420 · · Score: 1

    If Homo sapiens sapiens is around, then Homo sapiens is also around, as the former is a subspecies of the latter.

  45. Re:Cancer just doesn't have that "it" factor!! by meta-monkey · · Score: 1

    I bet there's a prostate cancer counter on tumblr. Every time it ticks up they hold a .gif party. One fewer male oppressor.

    --
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  46. Re:That's some good news by ImprovOmega · · Score: 1

    Wait...so the other 40% of homosexual men are celibate or virgins? Your stats appear to be made up.

  47. Re:Cancer just doesn't have that "it" factor!! by micahraleigh · · Score: 1

    First, that is not clear.

    Second, even if it was, calling someone a name is a pretty thin argument.

    Third, what is wrong with believing homosexuality is immoral? I think it is wrong. Obama thought it was wrong. You've got a lot of work to do if you're going to call all the people names that disagree with you.

  48. Re:Cancer just doesn't have that "it" factor!! by Rich0 · · Score: 1

    Ultimately, it is the immune system that keeps your body free of cancer. Cancers happen frequently in your body, and the immune system beats them down. When it fails at that for some reason, only then does clinical disease happen.

    You could make the same argument about MANY functions within your body. There are many different mechanisms in cells that work to prevent uncontrolled cell growth. There are many controls on the cell cycle which have to fail. The tumor needs to create demand for more blood vessels to sustain growth. The tumor has to evade the immune system, etc.

    It seems like cancer is the flip-side of multicellular life, and as a result humans have many different mechanisms for preventing it. Only when they all fail do cancers form. The problem is that you have billions of cells independently dividing and every time they do there is an opportunity for more mutations to creep in. Sooner or later any level of redundancy is bound to fail.