The use of nanoparticles and other nanoscale materials has been gathering a lot of significant interest in recent years and has even adapted into its own interdisciplinary field of science known as nanomedicine. Whilst there are still some issues to be ironed out within the nanomedicine field, it has brought about great advances within medicine, including many nanoparticle-based therapies for cancer. Given that the alternative to such treatments is longer periods of intensive chemotherapy and radiotherapy (although some therapies still use these processes but the cancer killing effects are more enhanced), there has been a lot of research dedicated to fighting cancer within the nanomedicine sector.
Cancer is currently on the rise. Currently, around every 1 in 8 males in the UK will be diagnosed with prostate cancer, with there being a significantly higher risk if the males are older, or if there is a pre-existing history of the cancer in the family. There are a range of nanoparticle therapeutic treatments undergoing developments, some of which are used to enhance the effects of chemotherapy and radiotherapy, whereas others deliver specific drugs to cancer cells.
Nanocarrier vessels are the most widely used therapeutic treatment for all types of cancer, as it enables the cancer-killing drug payload to be delivered to a specific site of interest (i.e. the tumour), whereupon the drug is released to the cancer cells, thus destroying them, whilst leaving the surrounding healthy cells undamaged. The same is true for prostate cancer, where specific drugs designed to kill prostate cancer cells can be loaded into the nanocarriers. Even though their regulatory viability is questionable, nanocarriers offer a much safer route to killing cancer cells (i.e. without causing unnecessary damage to healthy tissue), but not all nanocarriers are a viable option because of their inability to be excreted efficiently.
A lot of research in the early days of nanocarrier drug delivery systems focused on vessels of an inorganic nature, yet these are the types that are troublesome to break down or excrete. This has caused a shift in the types of nanocarrier vessels undergoing research at the fundamental level nowadays, and the shift has been towards organic-based vessels, such as liposomes. The shift has been attributed to a few factors, such as a much wider range of usable delivery vessels, but the most significant factors as to why organic nanocarriers are being used more and more is due to their much higher bioavailability, biocompatibility and the ability to be excreted by the body.
Another growing area, both academically and commercially, is the use of magnetic nanoparticles, i.e. nanoparticles composed of iron oxide to thermally treat cancer cells. Whilst iron oxide nanoparticles themselves are not highly biocompatible, their surface can be functionalized with biocompatible organic groups, such as polyethylene glycol (PEG), to make them suitable for use within the body. These particles can be directed remotely using an external magnetic field to the site of interest. Once the nanoparticles reach the cancerous site, they can be activated to undergo Brownian motion, which releases heat and destroys the cancer cells.
Nanoparticle Therapy in Recent News
Nanoparticle-based therapies for tackling prostate cancer has recently been in the news since a paper emerged in the Nature open-access journal, Scientific Reports. This new report details that their new therapy can be used to kill cancer cells and make tumours more sensitive to chemotherapy (a two-fold approach) and it is thought that it will reach clinical trials soon. Whilst it is a therapy that can be used with prostate cancer, it has also been stated that it is also usable for breast cancer.
The researchers use a core-shell lipid polymer hybrid nanoparticle to deliver two different drugs, rather than the conventional encapsulation of one drug, to the cancerous prostate. Both drugs used in the therapy are already FDA approved, which makes the transition to the clinic a lot smoother. One drug is an anti-cancer drug, known as docetaxel, and the other is a multiple sclerosis drug, known as fingolimod, that makes tumours more sensitive to chemotherapy treatments.
Both drugs have their disadvantages when used in a traditional capacity. Fingolimod is known to supress the immune system and be toxic in the blood, whereas docetaxel can produce serious side effects if the tumour is resistant to chemotherapy. So, by using a nanocarrier to target the specific area of interest, both drugs can know be administered together, with a much lower risk than ever before, to help kill cancerous prostate cell
Prostate Cancer UK: https://prostatecanceruk.org/prostate-information