What would a "cure for cancer" consist of?

Complex topic, simple question…

Everyone talks dreamily about curing cancer, but it’s not like a bacteria or virus that can be eradicated from the body, is it? What would a “cure for cancer” look like? Is the search actually getting anywhere? Are we waiting for just the right drug cocktail or chemo-type treatment?

All cancer cells have some common characteristics, so anything we could invent that could kill cells with those characteristics and no other cells would constitute a cure for cancer.

Failing that, genetic engineering may well produce a cure for cancer by making humans not get cancer in the first place.

Gotcha, thanks! And the second part of my question? Are we at all close to finding something like that? Just wondering what good those zillions of dollars are doing (hopefully a lot).

Could you really make someone immune to cancer? What about (hypothetical) exposure to radiation or something that directly affects the cells?

I’m not an oncologist, but I review a few research studies relating to oncology every year (for their statistical content) - I’ll share what I’ve picked up, but maybe someone else can chip in more information.

Are we close to finding something that will kill cancer cells only? Well, as I understand it, that depends on what kind of cancer cells you are talking about. There are many different types. Some chemo agents work pretty well against certain types of cancer, but there are other types of cancer that are extremely difficult to kill, or even slow/stop the growth of.

One of the past developments that got people really excited was the creation of drugs that slowed or prevented blood vessels from growing to feed tumors. In theory, this prevented them from growing by not permitting them to increase their food (blood) supply. In reality, these agents weren’t as effective as had been hoped.

A lot of the research studies that I see are simply studies to combine different existing regimens of chemo and/or radiation, in hopes of finding something that will add a couple of months to patients’ remaining lifespans. Whether this is really forward-thinking research that will lead to treatment breakthroughs is up for debate. I’ve seen one or two more recently that dealt with trying to develop a “vaccine” - this was pretty interesting to read about, and it requires the product to be tailored to each patient’s tumor cells. As far as a universal cancer vaccine goes, though, I’m not sure that’s possible, just because there are so many different types of cancer and some may be entirely unique to their hosts.

The only thing that would prevent people from getting cancer would be an agent that prevented changes in their DNA. Cells alter their growth and become tumors because of changes in their DNA. However, some other processes in the human body, like those related to some aspects of immunity, depend on the effects of mutation for effective function. If we look at ways to stop tumor growth after these changes have already taken place, then we’re dealing with either a drug/radiation that kills the cells (hopefully selectively!) or a way to make our immune systems recognize the cells as invaders, and mount an appropriate response.

Something that kills every single cancer cell, and leaves every single non-cancer cell alone? Probably not; that might never happen. Something that kills most cancer cells, but leaves most non-cancer cells alone? That depends on what you mean by “most”. The main area of research is refining the treatments we have so that they’ll kill more of the cancer cells, and less of the non-cancer cells. It probably won’t be a matter of “Poof! Cancer is suddenly eradicated!”, but more a matter of treatments gradually getting better and better.

Cancer is a catch-all term that covers dozens of different conditions, each with their own characteristics. The more we learn about it, the more complexity we find. It seems unlikely at this point to think that we’ll ever find a magic bullet cure where you can say, “take this pill and you’ll be cured.” It’s just not that simple. But we are making huge strides in diagnosis and treatment. People now routinely survive cancers that would have been a death sentence a few decades ago.

I know that this sounds weird, but I’ve sometimes wondered if maybe cancer will cure itself–in the sense of the evolution of the present human species.

Could cancer possibly be a group of diseases, that (while catastrophic to the individual), might be part of a slow, imperceptable physical evolutionary change in the human body, that will present itself in the far future of the human species as something with survival value?

In other words, could something like the accelerated, uncontrolled cell growth as we see in cancers today, perhaps be leading (in the far future of the human species), to something like natural limb regeneration or organ regrowth.

If that’s the case, couldn’t we still fight and hopefully cure cancers in individuals without blocking an apparent ongoing evolutionary process?

If I undertand it right ever childhood cancer survivor would unfortunately be a potential carrier of the trait. Since it is unfathomable to let kids die if they can be cured, it is less likely to kill the person before reaching reproductive age. IF it occurs after reproduction, then its already been passed on.

Not all cancers are based on genetics either so even then it would not cure everything. (pointed out by my wife Cyn on preview)

You’d need something that would:

  1. identify growth receptors on tumor cells (and block them);

  2. selectively induce cell death in tumor cells;

  3. detect and fix errors in the mechanisms that lead to unregulated cell reproduction

  4. effectively mark tumor cells for identification and annhilation by the immune system

  5. kill the tumors’ blood supply (selective angioinhibition)

We have experimental therapies involving vaccines (4) and growth inhibition (1), as well as old and new angioinhibitors(5). Items for (2) and (3) would effectively prevent cancer in its early stages.

Yeah, right. I reveal what the cure for cancer consists of and you steal it. Do I look like I was born yesterday? :smiley:

Possible cures could be along the lines of imatinib (trademarks: Gleevec (US) and Glivec (Europe)). This is a drug that cures (well, more or less) chronic myeloid leukemia (CML) with few side effects.

CML is caused by a specific chromosomal abnormality (called the Philadelphia chromosome) where chromosomes 9 and 22 exchange some material. The result is an abnormal enzyme called a tyrosine kinase which causes white blood cells to proliferate out of control. Imatinib binds to this tyrosine kinase and prevents it from functioning. Eventually the number of white blood cells with that defect drops to very low levels, although from what I understand, none of the patients are considered actually cured. Imatinib is also somewhat effective against another kind of cancer called gastrointestinal stromal tumors (GIST) and some other cancers, although it’s not as good against these as it is against CML.

It also doesn’t work for all cases and sometimes it stops working after having worked for some time. Two new drugs still in testing, dasatinib and nilotinib, seem to do a better job of suppressing the abnormal tyrosine kinase, so perhaps an actual cure for CML is in sight.

At any rate, this is a case where they focused on the chemical abnormality that caused the cancer and found a drug that inhibits its functioning. No doubt this is being attempted for other chromosomal abnormalities that cause cancer, but I don’t think anyone’s reported any successes yet.

No.

I think in the future that most cancer drugs will work in a similar way to Glivec.

Drugs which targets the abnormal mutations specific to the cancer cells and prevent those cells from replicating, or causing them to self-destruct (apoptose) look like they may be the way forward.

This might mean that cancer patients would have to take a pill everyday for the rest of their lives, but that “the rest of their lives” could be as long as for anyone else.

For the US audience, Glivec=Gleevec.

I think that the best hope for metastatic cancer involves angioinhibition: if we can stop angiogenesis, then we can kill or contain or prevent significant metastasis.

Having said that, the lieukemias and lymphomas are a different kettle of fish.

As long as we’re fantasizing…

The quickest and most efficient way to deal with a cell that has become reproductively uninhibited through genetic change is to kill it. But am I allowed to imagine a drug or, even, fleet of miniature robots, that would selectively undo the genetic damage?

After all, there is a process in nature that typifies this. The reversion of childhood ganglioneuroblastoma to pure gangliomas. Stage IV neuroblastoma spontaneously (or under the influence of chemotherapy) self-curing. The “blueberry muffin baby” survivors.

As a pathologist I fantasize this through a series of visual images of that horrible hepatocellular I saw last week, gradually losing the bizarreness of its nuclei and its multinucleation, achieving more and more cytoplasm-to-nucleus ratio, abandoning its ten-cell-layer-thick plates, settling down into nice little neighborhoods of friendly wiling cells, and finally becoming a ball of useless liver in the middle of the normal liver. (Useless because of no sensibly distributed portal triads or central veins. But a good neighbor)

I imagine its metastases to the lungs turning into harmless hamartomas.

Of course I have no idea how, but can’t I visualise?

Well, you could have a nanoframe, with one end sporting a receptor (to bind to that site of which you speak, the one with the mutation needing repair) and the other end sporting the fixy bit, the correct gene or chromosome or whatever the hell). You’d need a mechanism that would initiate the splice, say some sort of agent that is released when the receptor bit binds to something. Then the splicy bit activates, lets the fixy bit out, and splices it in.

Selective pressure could still operate under these circumstances; if, for example, loss of a parent put the offspring at some kind of social or economic disadvantage conferring statistically lower reproductive success.

You’re making the mistake of assuming that evolution has a long-term plan. It doesn’t. Evolution can only work with what it has right now, and that’s all it “knows” about. The way that evolution works on cancer is that, presumably, individuals with cancer tend to have fewer descendants (either by dying before they can have kids, or dying before the kids are independant and the kids starve, etc.). So to the extent that cancer is genetic, it would be slightly less common in each successive generation.

Now, it is conceivable that some day, one of the genes which causes or predisposes to cancer will mutate and allow individuals with that gene to regenerate organs or the like. If that ever happens (which is by no means assured, and in fact is pretty unlikely), then individuals with that mutated gene might well have an advantage. If the advantage is strong enough, then you’d expect to see it spread through the gene pool, until all humans were able to regenerate. But that hasn’t happened yet, so for now, cancer is still (to some extent) selected against by natural selection, and to a much greater extent, targetted by human researchers.

Better yet, just take a nanoframe with on end being a receptor and the other end some caged low half-life particle (technetium-99?). The various nanoframes bind to the cancer cells, you scan for the associated particle, and zap it with a multiply focused radiation gun, thereby minimizing damage to surrounding tissue.

Although not nearly as elegant as actual repair of the cancerous cell, this would allow one to kill the cancerous cell and takes care of the complexity inherent to gene splicing. Kill the thing, don’t fix it, kind of mentality.

While we are fantasizing, I envision that we would go to a hospital every so often (depending on risk factor), and in the course of a half hour or so have every cancerous cluster of cells in our body zapped into oblivion. Our body’s natural waste removal process could then clean it out the dead material, or if that doesn’t happen, it just lives on as inert/benign dead cell matter.

In the September 1986 issue of The Magazine of Fantasy & Science Fiction, Isaac Asimov had an article titled “The Enemy Within”, in which he points out that each of the billions of cells in the human body contain DNA, which itself contains numerous atoms of carbon. Though carbon is almost always in the friendly stable isotope carbon-12 (or less commonly, -13), a small amount is invariably the less less stable carbon-14 (or far less commonly, other isotopes). C-14 has identical chemical properties as C-12, and as long as it doesn’t decay, will work just fine. Sometimes decay does occur, though, and even though the rate is very slow compared to a human lifetime, but there are so many places C-14 can lurk in the body that breakdowns are occurring all the time. Each time a DNA C-14 breaks apart, it has the potential to shatter the entire strand. Most of the resulting fragments aren’t viable and are quickly broken down, but sometimes they begin replicating out of control and cancer results, completely independent of environmental factors like smoking or radiation exposure.

If there’s a cure for cancer, it’ll have to be something that either attacks these damaged strains or keeps them from growing. I expect it’ll be a maintenance treatment with regular doses, like insulin. Kim Stanley Robinson’s novel Red Mars speculates on such a treatment, necessary for Martian colonists who get large amounts of radiation exposure because of Mars’ thin atmosphere, with the nice side-effect that it greatly extends life.