The nanowarrior: using nanomedicine to fight cancer
At first glance nanomedicine seems like the stuff of science fiction. But it’s already here, and Dr Khuloud Al-Jamal, Senior Lecturer in Nanomedicine at King’s College London tells us how it’s helping to beat cancer.
A branch of medicine where travelling around blood vessels in a tiny spaceship is all in a day’s work? More than slightly reminiscent of the forgotten 1980s film Inner Space it’s true. But in essence, that’s just what nanomedicine is. Sending tiny molecular spaceships loaded with drugs into the human body, destined to battle disease.
“We design different types of very, very, small- nanosized- carriers that can deliver either drug molecules or biological agents to cells,” explains Dr Al-Jamal.
“These ‘nanocarriers’ act as a vehicle, helping to direct the drug to where it should go. For example, sometimes a new drug might have a problem dissolving in water or blood samples, or permeating through cell or target tissue on its own. So you need to use the nanocarrier as a kind of tiny car, to deliver the drug to that particular cell.”
From silica, to protein and fat-like molecules, to tiny gold particles. Nanocarriers come in many forms but have one thing in common- they are all tiny. Ranging from just 1 to 100 nanometers across, nanocarriers are dwarfed by human red blood cells which lumber in at a hefty 6000 to 8000 nanometers wide.
And that’s where the nanowarrier’s skills lie, using their knowledge of chemistry and physics to design, develop and manipulate these miniscule vehicles.
Nanomedicine in cancer
But just how is nanomedicine helping cancer? Dr Al-Jamal explains: “Cancer can especially benefit from nanomedicine because tumour cells have different properties to healthy cells. Their special physiology makes them particularly well suited. For example, some types have different genetic profiles and different receptors on their surface. When we engineer nanocarriers we can use these different characteristics to help them selectively target and move in on cancer cells.”
“Tumours also have leaky blood vessels. This is great for us because it means nanocarriers can escape through these leaky vessels at the site of the tumour, but won’t be able to reach most healthy cell types, where blood vessels are more intact.”
“Another beauty of nanocarriers is that they can also be designed to ‘codeliver’ more than one type of drug at the same time. This makes them ripe for use in combination therapy to treat cancer.”
As the name suggests, combination therapies combine two or more different treatments simultaneously. The aim is to hit cancer twice as hard with one shot, and reduce levels of treatment resistance. Dr Al-Jamal’s project with Worldwide Cancer Research, where she is using nanotechnology to improve radiotherapy efficiency in cancer, is a good example of how nanotechnology could improve combination therapies.
“We are developing nanocapsules which can deliver both radiation particles and small molecules called siRNAs to cancer cells,” explains Dr Al-Jamal.
“These siRNAs can manipulate and switch off certain genes that help the cancer cells withstand radiotherapy, and make them become ‘radioresistant’. By delivering the siRNA at the same time as the radiotherapy, we hope to make the cell more susceptible to destruction by internal radiation. Ultimately we think this will mean patients need smaller doses of radiation, causing less harm to healthy cells, and therefore less side-effects.”
What’s next for nanomedicine?
By all accounts nanomedicine is coming on in more than just nano-sized leaps and bounds. Admittedly, there’s a way to go before we are all popping tiny spaceships loaded-up with vitamins. But there are already numerous nanomedicine-based cancer therapies are in clinical trials, and some are already on the market . A remarkable achievement for a relatively young area of medicine.
“When I did my PhD in 2000, the nanofield was actually very, very, new.” Explains Dr Al-Jamal. “Back then it was called ‘drug delivery’, because it was all about using nanocarriers to deliver drugs. Now the field has expanded, and it’s not only drugs being delivered, but also other larger molecules like gene therapy agents, and imaging molecules. We’re not just looking to use nanocarriers to treat disease, but also to diagnose and follow the progress of the disease too.”
But what’s next? Cancer management is changing all the time, and nanomedicine must change too.
“I think that with the move towards more personalised medicine, where a patient receives a cancer treatment specifically tailored to the genetic and biological profile of the cancer they have, we will start to see nanomedicine being used in the clinic more and more. Nanocarriers will be used either to deliver that patient’s specific combination of treatments, or to help improve how well the therapy targets cancer cells, while leaving healthy cells alone,” says Dr Al-Jamal.
“Nanomedicine will also help improve diagnosis and monitoring of cancer. I think we will be able to develop very selective nanocarriers for detecting even small numbers of cancer cells- so it can be picked-up very early, and we can monitor it closely.”
From diagnosis to treatment- it seems nanomedicine really is set for big things.
Dr Al-Jamal and Izzat Suffian’s beautiful microscope image of breast cancer cells treated by nanocarriers loaded with the anticancer drug doxorubicin was a winning picture in the 2014 Wellcome Image Awards.