As summer finally arrives for most of the UK and we’re spending more time outside in the sunshine at Wimbledon, Glastonbury, or maybe just pottering around the garden, scientists in Chicago have been studying the potential anti-skin-cancer benefits of caffeine. The paper was a challenging read as it’s pretty much completely unrelated to what I spend my days doing but hopefully I’ve understood it enough to share a bit with you….
As you may already know from your bottles of Soltan, ultraviolet radiation B (UVB) rays are the main component of sunshine that can cause skin cancer. They do this by damaging the DNA in our skin cells – the damaged DNA is then recognised by the cell causing it to die. Problems happen when the cells containing the damaged DNA don’t die and instead, because of the damage caused by the UVB rays, they start to grow uncontrollably – this is cancer.
In the paper, the scientists are studying the effects of caffeine on the different systems responsible for causing the cell to die, or not. To start with they fired UVB rays at some cells grown in the lab and measured how many of the damaged cells died. When they added caffeine to the cells, more of them died meaning the chance of damaged cells becoming cancerous would be less. When caffeine was added to cells which had not been fired with UVB rays it made no significant difference.
One of the proteins responsible for the uncontrolled cell growth in cancer is called AKT – whose job it is to keep cells alive. Sometimes when skin cells are exposed to UVB rays, AKT is incorrectly ‘switched on’ which means cells are kept alive when they actually contain damaged DNA and should die. When caffeine was added to the cells that had been damaged by UVB rays the amount of AKT that was ‘switched on’ was much lower than when caffeine wasn’t added meaning these potentially cancerous cells will die (as they should).
This work has only touched on some of the many possible ways that caffeine may help prevent cancer, other systems are being studied and, as is common in science, some of them don’t agree with what was published here – maybe these scientists in Chicago are just trying to come up with an excuse to drink more coffee!! Importantly the paper only looks at cells grown in the lab and not as part of a whole animal or human – maybe the results would be completely different. Please note, I am by no means encouraging you to drink more coffee, as a decaffeinated person I would actually encourage the opposite 🙂
My first post may be considered a bit of a cheat as the subject is very closely related to my own research, but we have to start somewhere! This paper talks about how this group have changed the shape of an enzyme to change the way it works. The work all revolves around a chemical called perillyl alcohol which could be an effective anti-cancer drug. At the moment perillyl alcohol is purified from natural sources such as lavender oil and cherries but, as it is only there in very low levels, this is an expensive process. In order to make this chemical more feasible as a drug we need to come up with a cheap way of making loads of it. And the answer lies in enzymes.
For those of you who’ve forgotten high school biology, enzymes are proteins which catalyse reactions, which means they take a one chemical (called the substrate) and turn it into another (the product) millions of times faster than the same reaction would occur without the enzyme. Enzymes exist in all living systems; they are involved in making our cells, in breaking down our food…. without enzymes nothing would happen fast enough for life to exist! The bit you’ll probably remember about enzymes is that they are very specific, that is they will only bind substrates of a specific shape (lock & key model and all that). Depending on how the initial substrate binds you’ll then only get specific products released, and this is where the paper comes in.
They found an enzyme (with the great name of CYP102A1) which binds a substrate called limonene which can be very cheaply extracted at high levels from lemons. CYP102A1 converts limonene into a number of different products depending on how it binds the limonene. All of these products are very similar to our friend perillyl alcohol but with some key differences that mean they won’t work as an anti-cancer drug. The group of scientists therefore decided to examine, using some pretty swanky computer simulations, what it was about the shape of the binding site on CYP102A1 that meant it wouldn’t convert limonene into perillyl alcohol. Once they’d identified the important bits of the enzyme they changed them in various different ways and carried out some trials to see if the enzyme would now generate some perillyl alcohol when they fed it limonene. It took a couple of attempts but in the end they made three changes which meant the CYP102A1 now converts 97% of the limonene into perillyl alcohol and only 3% into other useless products. This is quite an achievement and now means that the enzyme could be used on an industrial scale to make bucket loads of perillyl alcohol which may one day help people suffering with cancer.
It is fairly intimidating starting a blog. Potentially, thousands of people could read, and judge, what I write (although I’m sure I won’t be that successful!) So I apologise for my humble beginnings, this is an experiment and with any luck, my writing will go from strength to strength.
The aim of my blog is to increase the accessibility of current scientific research to the general (non-scientific) public. I want to focus on the advances and the publications that don’t make the headlines, the work that will lead somewhere in the long run but hasn’t necessarily solved a major problem, cured a major disease or found a new way to live more sustainably. The research I hope to write about is what most research scientists spend their careers doing – small bits here and there that are built upon by other scientists to increase our understanding of a particular system, test hypotheses of how we can exploit a process to make life a little easier or design something new using the knowledge we’ve acquired through centuries of scientific discovery.
The posts are short, bite-size if you like; making it easy to take in the snippet of information I present and still have time to get on with all the other things you have to do. In just 5 or 10 minutes you can find out something a little bit cool… I hope you enjoy reading!