Tuesday, March 20, 2012

Nanotech enables radiation-induced tumour destruction

A new technique is set to greatly increase the power by which radiation therapy destroys tumour cells. Scientists at the University of Texas have found a way to create nanostructures that can be loaded with radiation and deliver them locally to brain tumours. By making sure it barely leaks, cancer cells get the full load, while healthy surrounding tissue remains intact. Because radiation therapy, despite the development of novel methods to combat brain cancer, is still the most widely used form of treatment, this could save many lives.

The nanoparticles are supposed to deliver their toxic content specifically to tumour cells. To provide the necessary radiation, the structure contains rhenium-186, which is radioactive and sheds off electrons, known as beta radiation. Because it is harmful for cells, it needs to be administered locally. The radiation-packed particle is built with spherical fat molecules called liposomes. Most nanostructures consist of a carbon core, such as the ones currently being tested for use in breast cancer.

Because the nanoparticles help with the drug reaching its destination, it can pack a bigger punch than ordinary radiation treatment. Simply irradiating the brain will rapidly result in side effects because surrounding healthy tissue is easily damaged. Because of local delivery, the dose can be increased 20-30-fold, compared to conventional radiation therapies. Needless to say, this greatly increases its tumour-eradicating potential. According to the scientists that performed the experiments, the radiation only spreads out a few millimetres, highlighting its precise targeting. Additionally, this specific form of rhenium, also known as an isotope, has a short half life, which means it disappears readily from the body. This is beneficial, because we would not want to have it lingering in the brain for too long.

A study with nanoparticles containing rhenium-186 was performed in rats. Human tests are obviously necessary, and they are scheduled to start pretty soon. This is good news for patients suffering from glioblastoma, one of the most common and deadly forms of cancer that resides in the head. It remains to be seen whether the treatment will be equally effective in human patients: it could prove to be harder to get the drug where it is needed, as we are more complex beings than rats. Nevertheless, rats are often used as a model organism because of their striking similarities when it comes to physiology.

Other options
As stated before, there are many options being explored to improve brain cancer treatment. Scientists appear to have high expectancies of nanoparticles, which are currently being tested in various labs around the world. Also, attempts are being made to trick cancer cells into taking up poisonous sugar, or enabling the immune system to help us by vaccinating patients suffering from brain cancer.
A patient suffering from glioblastoma. Visible as a white spot.

No comments:

Post a Comment