Tag Archives: cancer

Our cancerous common ancestor?

Peter Watts, still recovering from a close brush with mortality in the form of a flesh-eating virus (pictures NSFL – Not Safe For Lunch), blogs an interesting new scientific paper that suggests that we are all cancer. Take it away, Mister Watts:

I don’t mean this proximally. I mean it in the sense that all birds are dinosaurs — because according to Davies & Lineweaver, cancer (more precisely, “tumor-like neoplasms”) is the common ancestor of all animal life. Every malignant lump on your breast, every metastatic colony proliferating through your marrow, is just a rebooted revisitation of your grandmother a million times removed.

The basic idea’s petty straightforward. Natural selection reaches into every corner of the biosphere, you see; and a billion years ago that meant every cell for itself because unicellular life was the only game in town. A mere six hundred million years back, though, all that had changed. Metazoans were everywhere — cells grouped into colonies with specialized subsystems called tissues and organs —and somehow, within those colonies, the whole beat-the-competition thing had fallen out of favor. Cells worked together, now; hell, red blood cells even gave up their nuclei for the good of the organism, which really puts the kibosh on any future solo career. I think it had something to do with inclusive fitness.

In between, presumably, there was something halfway between Cuba and the US, some intermediate form between everyone for themselves and everyone for the state. Some kind of loose affiliation of cells which valued their individual freedom, but were not above at least some level of cooperation. Modern-day sponges might be a pretty good example: some cellular specialization, a bit of the ol’ helping hand between cells, but nothing so altruistic as an actual tissue. Call it “Metazoa 1.0″. Davies and Lineweaver do.

According to D&L, that old 1.0 operating system is still sleeping down there in our genetic code; it’s just been turned off by the more recent regulatory genes of Metazoa 2.0. It hasn’t been eradicated outright, because a lot of those ancient genes are still useful (“…the genes responsible for the cellular cooperation necessary for multicellularity are also the genes that malfunction in cancer cells.”) It’s just been — tamed, is as good a word as any. Tamed, and deactivated.

Except when something happens to one of those bits of regulatory code that keep it comatose. When some base pair flips this way instead of that, Metazoa 1.0 wakes up, its ancestral toolkit intact, ready to party like it’s One Billion Years B.P.

Watts, trained scientists that he is, is at pains to point out that Davies & Lineweaver are merely looking at old data with a new interpretation, and that they’ve put forward a theory rather than a statement of fact… and yeah, I know most of you who read here already know the difference, but this is the internet, after all. But…

… the great thing about being a science fiction writer is that I don’t really have to wait if I don’t want to. Here is an idea, peer-reviewed and legitimately published, thrown into discourse: We are all descended from Cancer. We are borne of the Holy Tumor. Isn’t that a thought. Doesn’t that get your mind going: to the imagination of ancient habitats, somewhere on this planet or within it. To isolated refugia, cut off from the rest of the world when stromatolites were still young, where 2.0 never happened and the cancerous Metazoan prototype was free to chart its own evolutionary course through a billion years.

I find these sorts of insights into the genesis of story ideas fascinating (as I do the science at the root of them). Though I’m kinda surprised that a guy who was nearly killed off by some incredibly virulent and weird disease a few weeks back (on the tail of having narrowly avoided becoming an anomalous Canadian blip in the 2010 immigration law incarceration statistics of the United States) needs to read biology papers to find potentially horrifying things to write about…

An Old Enemy: Fighting Cancer

So how did I go from last month’s topic about geoengineering to cancer treatment? Well, for one, keeping the Earth healthy is a bit like doing the same for humans: harder than you’d think. Systems engineering on a fairly complex level that we don’t entirely understand. This is also a personal topic. Cancer used to be an academic concept for me. Not any more. Science fiction lost a brilliant voice to cancer earlier this year, when Kage Baker died of it. Now I have friends and family with cancer, and it has become a palpable evil rather than something distant that I don’t want, like elephantiasis or malaria. I’ve seen it, and I don’t like it. Continue reading An Old Enemy: Fighting Cancer

Reaching an accomodation with cancer

cancer cellsIn the Western world at least, cancer is one of our most intractable enemies; medical science has advanced hugely in the last half-century, and cancer mortality rates have fallen as a result of preventative measures, but the essential approach remains the same as it ever has been – eradicate the tumour cells from the body at any cost.

Mathematical oncologist Robert Gatenby reckons that’s the wrong route, though. He suggests that rather than doing our utmost to purge cancer from the body, we should instead seek to reach a form of compromise with it – playing it to a stalemate, in other words, treating it as an inevitability to be controlled rather than an alien incursion to be expelled.

How people treat invasive species can provide an analogy for thinking about cancer therapy. In treating a field for a pest, for example, you might treat three-quarters of it with a pesticide, and leave the other quarter untreated. Pesticide-sensitive pests remain there, and they spread out into the field after treatment, preventing pesticide resistance from becoming dominant.

Using pesticides on an entire field is like what we’re doing with cancer now. And we all agree that we’d rather get rid of the pests altogether, but if you can’t do it, if every time you have an infestation you treat it and get resistance, then you try a different strategy. The alternative is to try to reduce the pest population so that it doesn’t damage your crop, and accept the fact that they’re going to be there. That’s what I’m talking about with cancer.

There’s a certain seductive logic to Gatenby’s idea; it chimes in harmony with the more systemic approaches we’re starting to take to agriculture and the environment, for example. Obviously, there’s a lot of research to be done to check whether or not he’s on to something, but the prospect of higher cancer survival rates using the drugs and treatments we already have to hand is a heartening one. [image by euthman]

Viruses used to kill cancer cells

tamedviruswiA fascinating concept: researchers at the University of Oxford have developed a method that uses modified viruses to destroy cancerous cells, whilst leaving healthy cells intact:

The research team modified a common virus – called an adenovirus – so that it could deliver genetic therapy to destroy tumours without poisoning the liver.

The changes enabled the virus to keeps its natural ‘infectious’ characteristics to replicate in, and kill, cancer cells in mice.

But for the first time the virus is also recognised and destroyed by healthy mouse liver cells, so it is no longer toxic.

Poachers make the best gamekeepers, no?

[from Physorg][image from Physorg]

Cure your cancer by contracting a virus

Seneca Valley oncolytic virus structureThe race to find a cure for cancer continues among a number of vectors, the better known of which are chemotherapy and gene therapy. But there are other methods being developed, including oncolytic viruses.

The Seneca Valley Virus is a naturally-occurring (and untweaked) virus which has been shown in clinical trials to be remarkably effective at treating some of the more nasty human cancer types while presenting no threat to the human body itself.

The biggest upside of oncolytic viral treatments is that they can be used on cancers for which there is no viable surgical procedure, though their ability to travel through the bloodstream and work on metastatic cases as well as local ones is good news too. [image from Wikimedia Commons]