radiolabeled NPs. Thus, meticulous and comprehensive understanding chemistry
and biology of NPs is required to develop successful radionanomedicine
therapeutics.
23.4 Enhancement of Radiolabeled Nanoparticles
for Effective Therapy
Gold nanoparticles (AuNPs) are one of the most actively investigated NPs for
cancer treatment, and modification was suggested to enhance therapeutic effects of
AuNPs. AuNPs have been proposed as localized heat sources for cancer treatment
utilizing two relevant properties of gold; resistance to oxidation and plasmon resonance with light [15]. Another beneficial property of gold is thermo-ablation,
which is produced by non-ionizing radiation such as microwaves or radiofrequency
(RF). AuNPs released heat to destroy malignant cells by means of absorbing RF
energy [16]. Besides AuNPs, several NPs such as iron oxide NPs or carbon NPs can
generate thermal heat. For example, iron oxide NPs released heat when they
were activated by an external alternating magnetic field, and then they induced
necrosis of the tumor microenvironment [17].
As well as utilizing intrinsic properties of AuNPs, various attempts have been
performed to modify AuNPs for efficient cancer theranostics. AuNPs can be
conjugated with peptides targeting a specific receptor on tumor cells, e.g. tumor
angiogenesis. Tumor angiogenesis is a well-known biologic process essential to
tumor growth. As an imaging biomarker and a promising therapeutic tactic targeting tumor angiogenesis, arginine-glycine-aspartate (RGD) peptides have been
actively investigated, since it antagonize avb3 integrin thereby effectively
inhibiting angiogenesis. The conjugation of RGD peptides to radiolabeled gold
nanoparticles (
177 Lu–RGD–AuNP) was evaluated for the treatment of glioma, and
it induced significantly less tumor progression in vivo [18]. Radiolabeled bombesin can also be used for cancer treatment. Bombesin is a tetradecapeptide that
has a high binding affinity to the gastrin-releasing peptide receptor (GRP). The
overexpression of GRP was imaged by radiolabeled bombesin on primary prostate
cancer and their metastatic lymph nodes in xenografts [19]. Bombesin conjugated
with
177 Lu–AuNP was investigated for the treatment of prostate cancer, utilizing
combination of photothermal therapy and radiation therapy [20]. This study also
demonstrated that the radiolabeled NPs exhibited properties that are suitable for
both plasmonic photothermal therapy and targeted radiotherapy in the treatment of
prostate cancer.
23 Therapeutic/Theranostic Use of Radionanomedicine
437
and biology of NPs is required to develop successful radionanomedicine
therapeutics.
23.4 Enhancement of Radiolabeled Nanoparticles
for Effective Therapy
Gold nanoparticles (AuNPs) are one of the most actively investigated NPs for
cancer treatment, and modification was suggested to enhance therapeutic effects of
AuNPs. AuNPs have been proposed as localized heat sources for cancer treatment
utilizing two relevant properties of gold; resistance to oxidation and plasmon resonance with light [15]. Another beneficial property of gold is thermo-ablation,
which is produced by non-ionizing radiation such as microwaves or radiofrequency
(RF). AuNPs released heat to destroy malignant cells by means of absorbing RF
energy [16]. Besides AuNPs, several NPs such as iron oxide NPs or carbon NPs can
generate thermal heat. For example, iron oxide NPs released heat when they
were activated by an external alternating magnetic field, and then they induced
necrosis of the tumor microenvironment [17].
As well as utilizing intrinsic properties of AuNPs, various attempts have been
performed to modify AuNPs for efficient cancer theranostics. AuNPs can be
conjugated with peptides targeting a specific receptor on tumor cells, e.g. tumor
angiogenesis. Tumor angiogenesis is a well-known biologic process essential to
tumor growth. As an imaging biomarker and a promising therapeutic tactic targeting tumor angiogenesis, arginine-glycine-aspartate (RGD) peptides have been
actively investigated, since it antagonize avb3 integrin thereby effectively
inhibiting angiogenesis. The conjugation of RGD peptides to radiolabeled gold
nanoparticles (
177 Lu–RGD–AuNP) was evaluated for the treatment of glioma, and
it induced significantly less tumor progression in vivo [18]. Radiolabeled bombesin can also be used for cancer treatment. Bombesin is a tetradecapeptide that
has a high binding affinity to the gastrin-releasing peptide receptor (GRP). The
overexpression of GRP was imaged by radiolabeled bombesin on primary prostate
cancer and their metastatic lymph nodes in xenografts [19]. Bombesin conjugated
with
177 Lu–AuNP was investigated for the treatment of prostate cancer, utilizing
combination of photothermal therapy and radiation therapy [20]. This study also
demonstrated that the radiolabeled NPs exhibited properties that are suitable for
both plasmonic photothermal therapy and targeted radiotherapy in the treatment of
prostate cancer.
23 Therapeutic/Theranostic Use of Radionanomedicine
437