Question: Could your create a bacteria that could save cancer victims and permentantly keep cancer away from them? and is so how far away is science to creating such a bacteria?

Mark Roberts answered on 24 Jun 2010:

To be honest the answer is kind of yes and no

Cancer is not just one disease – it’s cells proliferating out of control – your cells normally don’t divide when they don’t need to and in cancer this goes wrong – but your cells control this process in many ways so many different things could go wrong – this means to treat the cancer you’d need to treat each cancer differently – so lots of cures!

If we assume just targeting one cancer using bacteria – the main issue with any cancer treatment is specificity – these are your cells that cause cancer so they look like your cells (this is why your immune system doesn’t kill cancer!) so spotting the difference between a cancer cell you’d like to kill and a normal cell is a problem. You could try designing a bacteria to infect dividing cells – since that is what is causing the cancer but that will have side effects (eg hair loss) in other parts of your body where you need cells to divide. As we learn more in the future we may be able to find a way to tell cancer cells apart from normal cells better – if we do then yes you could target a bacteria to kill / infect those cells.

There are some further problems though – namely your own immune system! If you’re infecting yourself with bacteria your immune system will still react to it and try to kill it (just like it does with any infection) so if it’s going to be a usable treatment we’ll need a way to make the bacteria not recognised by the immune system

Phew – that was a long answer. In short. Yes it is in theory possible, at least as a temporary treatment rather than permanent cure. The science is still a long way off as it’s very difficult to do what you’ve just described. People are working on it and it is plausible, just hard!

Also to ‘find’ cancer cells bacteria will need to sense the outside world – so my research in understanding how that works will be important!