Nanoparticles are extremely small particles that can be modified for a variety of uses in the medical field. For example, nanoparticles can be engineered to be able to transport medicines specifically to the disease site while not interfering with healthy body parts.
Selective drug transport verified in human tissue for the first time
The Munich scientists have developed nanocarriers that only release the carried drugs in lung tumour areas. The team headed by Silke Meiners, Oliver Eickelberg and Sabine van Rijt from the Comprehensive Pneumology Center (HMGU), working with colleagues from the Chemistry Department (LMU) headed by Thomas Bein, were able to show nanoparticles’ selective drug release to human lung tumour tissue for the first time.
Tumour specific proteins were used to release drugs from the nanocarriers
Tumour tissue in the lung contains high concentrations of certain proteases, which are enzymes that break down and cut specific proteins. The scientists took advantage of this by modifying the nanocarriers with a protective layer that only these proteases can break down, a process that then releases the drug. Protease concentrations in the healthy lung tissue are too low to cleave this protective layer and so the medicines stay protected in the nanocarrier.
“Using these nanocarriers we can very selectively release a drug such as a chemotherapeutic agent specifically at the lung tumour,” reports research group leader Meiners. “We observed that the drug’s effectiveness in the tumour tissue was 10 to 25 times greater compared to when the drugs were used on their own. At the same time, this approach also makes it possible to decrease the total dose of medicines and consequently to reduce undesirable effects.”
Further studies will now be directed to examine the safety of the nanocarriers in vivo and verify the clinical efficacy in an advanced lung tumour mouse model.
Protease-Mediated Release of Chemotherapeutics from Mesoporous Silica Nanoparticles to ex Vivo Human and Mouse Lung Tumors van Rijt, S. et al. (2015): ACS Nano. doi: 10.1021/nn5070343