Tumor angiogenesis plays a key role in
tumor growth and
metastasis; thus, targeting
tumor-associated angiogenesis is an important goal in
cancer therapy. However, the efficient delivery of drugs to
tumors remains a key issue in antiangiogenesis
therapy. GX1, a
peptide identified by phage-display technology, is a novel
tumor vasculature endothelium-specific
ligand and possesses great potential as a targeted vector and
antiangiogenic agent in the diagnosis and treatment of human
cancers.
Endostar, a novel recombinant human
endostatin, has been shown to inhibit
tumor angiogenesis. In this study, we developed a
theranostic agent composed of GX1-conjugated
poly(lactic acid) nanoparticles encapsulating
Endostar (GPENs) and labeled with the near-infrared
dye IRDye 800CW to improve
colorectal tumor targeting and treatment efficacy in vivo. The in vivo fluorescence molecular imaging data showed that GPENs (
IRDye 800CW) more specifically targeted
tumors than free
IRDye 800CW in
colorectal tumor-bearing mice. Moreover, the antitumor efficacy was evaluated by bioluminescence imaging and immunohistology, revealing that GPENs possessed improved antitumor efficacy on subcutaneous colorectal xenografts compared to other treatment groups. Thus, our study showed that GPENs, a novel GX1
peptide guided form of nanoscale
Endostar, can be used as a
theranostic agent to facilitate more efficient targeted
therapy and enable real-time monitoring of therapeutic efficacy in vivo.