88
Z. Liu and Y. Liu
overexpressed SW620 colon cancer cells (Fig. 4.5c). These aptamers enhanced the
binding efficacy between nanoparticles (AP-MSN-DOX) and SW620 colon tumor
cells, then increased their cellular uptake and cytotoxicity to cancer cells, which
resulted in significant inhibition effects on SW620 cells.
Moreover, targeting ligands and tumor microenvironment triggered drug release
could be integrated in one system, thus providing an innovative method for
cancer therapy [59, 60]. Zahiri et al. [61] reported an Apt-PCDA-DMSN@DOX
hybrid nanoreservoir for CD133-targeted drug delivery. Dendritic mesoporous silica
nanoparticles (DMSNs) were utilized as the nanocarriers to load DOX. Then, polycarboxylic acid dextran (PCAD) was electrostatically capped on the surface of DMSNs.
The modification increased the biocompatibility of the nano-reservoir and endowed it
with pH-dependent drug release manner. Finally, an RNA aptamer which can specifically bind with cancer stem cell (CSC) marker CD133 was covalently attached to
the carboxyl groups of dextran and fabricated an Apt-PCDA-DMSN@DOX system.
The prepared drug delivery system efficiently delivered DOX to CD133
+ colorectal
cancer cells (HT29), and intelligently released the cargo in low pH condition. The
in vitro cytotoxicity experiments demonstrated that Apt-PCDA-DMSN@DOX has
significantly higher cellular uptake and cytotoxicity on HT29 (CD133
+ ) cells than
on CHO (CD133
− ) cells. This study indicated that the prepared nanodrug delivery
system provided a smart and promising approach to transport drugs to the site of
action in a safe and specific manner.
4.4.1.3 Iron Oxide Nanoparticles
Iron oxide nanoparticles were widely employed as targeted drug delivery platforms
due to their unique magnetic property and easy surface modification. However, the
lack of targeting accuracy has been a vital obstacle for iron oxide nanoparticles application in precise medicine. The selective and efficient delivery of the intended agent
to the desired site, which can be achieved through using proper targeting or recognition moieties. DNA aptamers are attractive in designing active drug delivery systems
due to their inherent advantages. Hassam et al. [62] developed AS1411 aptamerfunctionalized albumin loaded on iron oxide and gold nanoparticles for targeted
delivery of doxorubicin. The nanocarrier was synthesized by a desolvated crosslinking method and the synthesized nanoparticles were found to be spherical with
an average diameter of 120 nm and a zeta potential of about -50.3 mV. Anna et al.
[63] presented magneto-dynamic therapy for selective elimination of tumor cells
in vivo using DNA aptamer-functionalized magnetic nanoparticles exposed to a low
frequency alternating magnetic field. Specific delivery of the aptamer-conjugated
ferroarabinogalactan (FeAG) nanoparticles to the tumor site was confirmed by
magnetic resonance imaging (MRI). After treated with a low frequency alternating
magnetic field, the aptamer modified FeAG caused cancer cell death in vitro and
tumor volume reduction in vivo (Fig. 4.5d).
Z. Liu and Y. Liu
overexpressed SW620 colon cancer cells (Fig. 4.5c). These aptamers enhanced the
binding efficacy between nanoparticles (AP-MSN-DOX) and SW620 colon tumor
cells, then increased their cellular uptake and cytotoxicity to cancer cells, which
resulted in significant inhibition effects on SW620 cells.
Moreover, targeting ligands and tumor microenvironment triggered drug release
could be integrated in one system, thus providing an innovative method for
cancer therapy [59, 60]. Zahiri et al. [61] reported an Apt-PCDA-DMSN@DOX
hybrid nanoreservoir for CD133-targeted drug delivery. Dendritic mesoporous silica
nanoparticles (DMSNs) were utilized as the nanocarriers to load DOX. Then, polycarboxylic acid dextran (PCAD) was electrostatically capped on the surface of DMSNs.
The modification increased the biocompatibility of the nano-reservoir and endowed it
with pH-dependent drug release manner. Finally, an RNA aptamer which can specifically bind with cancer stem cell (CSC) marker CD133 was covalently attached to
the carboxyl groups of dextran and fabricated an Apt-PCDA-DMSN@DOX system.
The prepared drug delivery system efficiently delivered DOX to CD133
+ colorectal
cancer cells (HT29), and intelligently released the cargo in low pH condition. The
in vitro cytotoxicity experiments demonstrated that Apt-PCDA-DMSN@DOX has
significantly higher cellular uptake and cytotoxicity on HT29 (CD133
+ ) cells than
on CHO (CD133
− ) cells. This study indicated that the prepared nanodrug delivery
system provided a smart and promising approach to transport drugs to the site of
action in a safe and specific manner.
4.4.1.3 Iron Oxide Nanoparticles
Iron oxide nanoparticles were widely employed as targeted drug delivery platforms
due to their unique magnetic property and easy surface modification. However, the
lack of targeting accuracy has been a vital obstacle for iron oxide nanoparticles application in precise medicine. The selective and efficient delivery of the intended agent
to the desired site, which can be achieved through using proper targeting or recognition moieties. DNA aptamers are attractive in designing active drug delivery systems
due to their inherent advantages. Hassam et al. [62] developed AS1411 aptamerfunctionalized albumin loaded on iron oxide and gold nanoparticles for targeted
delivery of doxorubicin. The nanocarrier was synthesized by a desolvated crosslinking method and the synthesized nanoparticles were found to be spherical with
an average diameter of 120 nm and a zeta potential of about -50.3 mV. Anna et al.
[63] presented magneto-dynamic therapy for selective elimination of tumor cells
in vivo using DNA aptamer-functionalized magnetic nanoparticles exposed to a low
frequency alternating magnetic field. Specific delivery of the aptamer-conjugated
ferroarabinogalactan (FeAG) nanoparticles to the tumor site was confirmed by
magnetic resonance imaging (MRI). After treated with a low frequency alternating
magnetic field, the aptamer modified FeAG caused cancer cell death in vitro and
tumor volume reduction in vivo (Fig. 4.5d).