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Cancer is even more complicated than we thought

There's some really interesting—and rather disturbing—research coming out of the UK on the nature of cancer cells and why advanced-stage cancers are so difficult to treat.

Scientists have long known that the same type of cancer can play out in very different ways, from a genetic perspective, in one patient compared to another. But this new research shows that, even within the same patient—even within the same tumor—different samples of cancer cells have more genetic differences than they have similarities.

That's a very big deal. It means that cancer cells aren't just cells that grow uncontrollably. They also mutate. Which means that they evolve. That fact has serious implications for cancer treatment. Just like bacteria can evolve to become resistant to antibiotics, cancer cells can evolve resistance to the treatments we throw at them. At Not Exactly Rocket Science, Ed Yong explains how this discovery fits into the bigger picture of why curing cancer is so damned difficult:

For a start, cancer isn’t a single disease, so we can dispense with the idea of a single “cure”. There are over 200 different types, each with their own individual quirks. Even for a single type – say, breast cancer – there can be many different sub-types that demand different treatments. Even within a single subtype, one patient’s tumour can be very different from another’s. They could both have very different sets of mutated genes, which can affect their prognosis and which drugs they should take.

And now we know that's true within a tumor, as well. At the Cancer Research UK blog (where Ed used to work), Henry Scowcroft has a nice summary of how this one discovery explains three perplexing problems we've long had with cancer cells:

Firstly, cancer is very difficult to cure after it has spread. This is despite years of progress in chemotherapy and radiotherapy, two techniques that can offer respite to people with advanced cancer.

Secondly, most advanced cancers eventually become resistant to every type of drug used to treat them – both ‘traditional’ chemo and these newer agents. This is quite extraordinary: tumours can work out how to cope with chemicals that they’ve never ‘seen’ before – a biological superpower far beyond that of infectious diseases. Just consider how it’s taken ‘multidrug resistant’ bacteria like MRSA decades to evolve. Yet cancers can do this in a matter of months or even weeks. How?

And finally, researchers haven’t yet managed to develop tests to predict how a patient’s disease will progress, nor monitor their progress (a field called ‘biomarker’ research) – this is despite years of research, and a lot of tantalising pilot studies. Sometimes researchers detect a promising ‘signal’ by looking at samples from a handful of patients, only for this to disappear in larger numbers of people.

Read Ed Yong's full story on this research.

Read Henry Snowcroft's full story on this research.

Scary science, national security, and open-source research

I’ve been following the story about the scientists who have been working to figure out how H5N1 bird flu might become transmissible from human to human, the controversial research they used to study that question, and the federal recommendations that are now threatening to keep that research under wraps.

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Time-lapse video of lab-grown snowflakes

Back in December, researchers at Caltech posted a research paper to arXiv that attempts to explain why the shape and structure of snowflakes change significantly depending on relatively small shifts in temperature.

In order to study this, they had to grow snowflakes in laboratory conditions. It was not an easy thing to figure out how to do. On his Snowcrystals page, physicist Kenneth G. Libbrecht show you how it's done.

There are many ways to grow snowflakes, but my favorite starts with something called a vapor diffusion chamber. This is essentially nothing more than an insulated box that is kept cold on the bottom (say -40C) and hot on the top (say +40C). A source of water is placed at the top, and water vapor diffuses down through the box, producing supersaturated air. The cold, supersatured air at the center of the chamber is ideal for growing ice crystals.

While working with this diffusion chamber, we rediscovered a wonderful technique for growing synthetic snow crystals that was first published in 1963 by meteorologist Basil Mason and collaborators [1]. One starts by putting a wire into the diffusion chamber from below, so that small ice crystals begin growing on the wire's tip. Then apply a high voltage to the wire, say +2000 volts, and voila -- slender ice needles begin growing from the wire.

Video Link

Fish mimics mimic octopus

This is a great find by Not Exactly Rocket Science's Ed Yong. A tourist and a couple of researchers from the California Academy of Sciences have documented an instance of Pacific-dwelling jawfish hiding from predators by blending into the stripes of well-known camouflage guru, the mimic octopus.

This relationship is probably a rare occurrence. The black-marble jawfish is found throughout the Pacific from Japan to Australia, while the mimic octopus only hangs around Indonesia and Malaysia. For most of its range, the jawfish has no octopuses to hide against. Instead, Ross and Rocha think that this particular fish is engaging in “opportunistic mimicry”, taking advantage of a rare chance to share in an octopus’s protection.

Video Link

Thanks, Atvaark!

Forecast uncertain: Chaos theory, weather prediction, and brain cancer

A diagnosis of brain cancer is basically a death sentence. It’s a terrible thing for anyone to deal with, and it’s only made worse by all the uncertainty.

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Coffee: An antidepressant and religion preventative?

A recently published study found a correlation between higher rates of coffee drinking in women and decreased risk of depression. Naturally, that finding made headlines. But blogger Scicurious has a really nice analysis of the paper that picked up a significant flaw in the way the data is being interpreted. There was a correlation between drinking more coffee and a lowered risk of depression. But that wasn't the only correlation the researchers found—just the only correlation they made a big deal of in their conclusions.

On her blog, Scicurious lists the other correlations and explains why it's hard to draw any solid conclusion from this data set:

1) Smoking. The interaction between depression risk, smoking, and coffee consumption was “marginally” significant (p=0.06), but they dismiss it as being due to chance because it was “unexpected”. Um. Wait. Nicotine is a STIMULANT. It is known to have antidepressant like effects in animal models (though the withdrawal is no fun). This is not unexpected.

2) Drinking: heavy coffee drinkers drink more. But note that they don’t say that drinking coffee puts you at risk for drinking alcohol.

3) Obesity: heavy coffee drinkers are, on average, thinner, but not more physically active. They do not conclude that coffee drinking prevents obesity.

4) Church going: heavy coffee drinkers are less likely to go to church. Less likely to go to church, less likely to develop depression…heck, forget depression, maybe coffee prevents religion now! Now THAT would be a heck of a finding.

Here’s the thing. I do believe that high coffee consumption correlates with decreased risk of depression. But a lot of other things do as well. I am not convinced that the high coffee consumption wasn’t part of a lifestyle that correlated with decreased risk of depression, maybe they have stronger support networks or less incidence of depression in the family. It could be many other things.

Image: Coffee, a Creative Commons Attribution (2.0) image from dyobmit's photostream