The prestigious journal Nature Communications reveals
that silicon nanomaterials for the localized delivery of
chemotherapeutics behave differently in malignant tumors in comparison
to healthy tissues. The joint study was conducted at the Technion,
Massachusetts Institute of Technology (MIT) and the Harvard Medical
School.
“We have shown for the first time
that biomaterials in general, and nanostructured porous silicon in
particular, behave differently when they are injected (or implanted) at
the tumor microenvironment.” says Prof. Ester Segal, who heads the
Technion team that led the study. “Over the last few years, we
successfully engineered silicon to be used as a carrier of anticancer
drugs that releases its contents in a controlled manner, and now we
are focusing on the degradation mechanism of the silicon at the diseased
tissue.”
Nanostructured Porous Silicon is
the common name for a family of silicon-based materials containing
nano-scale holes. This material is today seen as a promising drug
delivery vehicle, mainly due to its unique characteristics: a large
surface area (geared for drug unloading), biocompatbility, and
bio-degradability in a safe and non-toxic manner. In recent years, Prof.
Segal and her doctoral student Adi Tzur-Balter developed ‘containers’
(carriers) for the delivery of anticancer drugs. Through careful design
of the silicon containers, in terms of their pore diameter and surface
chemistry, the group achieved optimal features for effective drug
delivery.
The important findings of the
study, which investigates the behaviour of the silicon ‘containers in
breast cancer tumors, are associated with the accelerated degradation of
the silicon material in the diseased area. The research showed that
reactive oxygen scecies upregulated in the cancerous environment (in vivo), induce oxidation of the silicon, causing a rapid degradation of the ‘containers’ as compared with (in vitro)
lab experiments. As a result, this article sheds light on the process
of nanostructured silicon degradation at the tumor microenvironment, and
allows for early and smart design intervention of the silicon structure
to facilitate controlled release of the drug at the targeted site.
Importantly, the ability to determine and predict material fate in vivo under specific environments is the next step in biomaterial design that could lead to fast and successful clinical translation.
Reference:
“Mechanism of Erosion of Nanostructured Porous Si Drug Carriers in Neoplastic Tissues”; Nature Communications.