Georgetown University researchers led by Dr Esther Chang have had some recent success with Phase 1 trials of cool little nanoliposomes (like fat only smaller) which fight cancer by gene therapy. Last time I checked, I thought gene therapy was years and years down the track, decades even, that it was the stuff of science fiction – but apparently it’s not as far away as I thought.
p53 is one of my all-time favourite gene/proteins because it does so many things – it has its fingers in a lot of pies, and I like pies. If you already know how p53 works, maybe it’s one of your favourites too, skip the following paragraph.
p53 is a tumour suppressor gene. A mutation that messes up your p53 is involved in over half of all human cancers, and is often one of the early mutations that a cell gets along the dark, dangerous, Darwinian path of becoming cancerous. Basically, p53 is activated when DNA is damaged and it stops the cell from replicating by stopping it before it enters the S phase and starts DNA synthesis, because it’s kickass and p53 knows that you don’t want to replicate mucked up DNA. When p53 is activated, a cell has two choices: to either repair the damage or kill itself. Without functional p53 DNA may get replicated with all kinds of errors, leading to multiple mutations and potentially cancer, and the cell is less likely to kill itself, leading to long-lived cells and potentially cancer.
So what these guys have done is pretty cool – they wrap up a section of DNA that has a functional copy of the p53 gene in a cationic liposome (positively charged hunk of fat).
When the liposome bumps into a cancer cell it sticks because of the tumour-specific antibodies and then, I’m assuming, the fat merges with the plasma membrane and the DNA segment is sent to the nucleus. The cancer cell now has a functioning copy of p53, and that will chafe it in the fun zone.
They’ve tried it on mice with human cancers grafted onto them (which is gross imho), and it made chemotherapy and radiotherapy more successful than control, so it seems to be working. Hell, I think gene therapy is pretty freaking cool, although a bit scary as well, and that this is an awesome idea. It’s futuristic and I’m feeling cautiously optimistic, how about you?