Nanoparticles release drugs only at the site of lung cancer
8 March 2015
German scientists have developed nanoparticles that release
drugs only in the presence of lung tumour cells in human and mouse
lungs. The particles were developed by Scientists from the Helmholtz
Zentrum München (HMGU) and the Ludwig-Maximilians-Universität (LMU)
in Munich who were working in a joint project at the Nanosystems
Initiative Munich Excellence Cluster.
In the journal, ACS Nano, the scientists reported that this
approach led to a significant increase in the effectiveness of
current cancer medicines in lung tumour tissue.
Nanoparticles are extremely small particles that can be modified
for a variety of uses in the medical field. For example, they can be
engineered to be able to transport medicines specifically to the
disease site while not interfering with healthy body parts.
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
nanoparticles 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
"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.
van Rijt, S. et al. 2015. Protease Mediated Release of
Chemotherapeutics From Mesoporous Silica Nanoparticles to Ex Vivo
Human and Mouse Lung Tumors, ACS Nano. doi: 10.1021/nn5070343. Link