Searching for a breast cancer cure
Jennifer Squire recently finished second in the Deakin University Three Minute Thesis finals. This is an edited version of her address.
Most of you here will know of someone who has been affected by this horrible disease, so I don’t really need to tell you that it is the most common cancer found in Australian women with one in nine diagnosed before the age of 85. And I certainly don’t need to tell you that there is no cure, only treatments like chemotherapy, that plough through the body like a bulldozer, destroying everything in its paths-including healthy tissue.
But what if we could selectively destroy just the cancerous cells so that healthy tissue was left alone? Well that’s where my research comes in – I am aiming to develop a chemotherapy drug delivery system that will only target and destroy cancer cells.
Cancer dominates over healthy cells because it grows very rapidly without any constraints. It does this by growing lots of tiny little blood vessels from one pre-existing vessel. However, this results in a tangled web of blood vessels, much like the roots of a weed, that are leaky, which allows particles of a certain size to easily pass through the walls of the blood vessel and into the tumour tissue.
Now liposomes and micelles, which are nano-sized particles, are the perfect size to do this.
So imagine if we put a current chemotherapy agent inside a liposome or micelle that would then act like a biological vehicle, driving the chemotherapeutic to the tumour whilst also shielding and protecting the surrounding healthy tissue from being harmed. Being the perfect size this vehicle will have no trouble getting into the tumour cells and releasing a high dose of the chemotherapy it is carrying directly into the heart of the tumour.
Breast cancer tumours also over express hormone receptors that ‘grab’ hormones, like estrogen from the blood stream, allowing the tumour to keep growing rapidly.
As a chemist I am trying to make a range of liposomes and micelles that have a chemotherapy agent, Tamoxifen, attached to the outside. The special thing about Tamoxifen is that it works by mimicking the hormone estrogen, so the receptor will grab and pull it into the tumour by mistake.
This is helpful as it acts like a GPS for our liposome, guiding it directly into the tumour where it can release a second dose of the different type of chemotherapy agent that it is carrying.
This double barreled delivery system has the potential to deliver a high dose of chemotherapy directly into breast cancer tumours whilst also minimising side effects.
So with my research, the very thing that gives cancer the competitive edge over our healthy cells could also ultimately bring about its demise.