RESUMEN
Early diagnosis and complete resection of the tumor is an important way to improve the quality of life of patients with gastric cancer. In recent years, near-infrared (NIR) materials show great potential in fluorescence-based imaging of the tumors. To realize a satisfying intraoperative fluorescence tumor imaging, there are two pre-requirements. One is to obtain a stable agent with a relatively longer circulation time. The second is to make it good biocompatible and specific targeting to the tumor. Here, we developed an RGD-modified Distearyl acylphosphatidyl ethanolamine-polyethylene glycol micelle (DSPE-PEG-RGD) to encapsulate indocyanine green (ICG) for targeting fluorescence imaging of gastric cancer, aimed at realizing tumor-targeted accumulation and NIR imaging. 1H NMR spectroscopy confirmed its molecular structure. The characteristics and stability results indicated that the DSPE-PEG-RGD@ICG had a relatively uniform size of <200 nm and longer-term fluorescence stability. RGD peptides had a high affinity to integrin αvß3 and the specific targeting effect on SGC7901 was assessed by confocal microscopy in vitro. Additionally, the results of cytotoxicity and blood compatibility in vitro were consistent with the acute toxicity test in vivo, which revealed good biocompatibility. The biodistribution and tumor targeting image of DSPE-PEG-RGD@ICG were observed by an imaging system in tumor-bearing mice. DSPE-PEG-RGD@ICG demonstrated an improved accumulation in tumors and longer circulation time when compared with free ICG or DSPE-PEG@ICG. In all, DSPE-PEG-RGD@ICG demonstrated ideal properties for tumor target imaging, thus, providing a promising way for the detection and accurate resection of gastric cancer.
RESUMEN
At present, cancer is the first cause of death for humans, but early detection and treatment can help improve prognoses and reduce mortality. However, further development of carrier-assistant drug delivery systems (DDSs) is retarded by the aspects such as the low drug-carrying capacity, carrier-induced toxicity and immunogenicity, complex synthesis manipulation. The development of nanoscale drug delivery systems (NDDS) have been rapidly developed to address these issues. In this article, we used PLGA-PEG with good biocompatibility to encapsulate Fe3O4 nanoparticles (a magnetic resonance imaging contrast agent) and DOX (an antitumour drug) via the emulsion-solvent evaporation method, aimed at achieving a dual function of the early detection and the treatment of mammary cancer. The results showed that the Fe3O4/DOX/PLGA-PEG nanoparticles had a relatively uniform size, a high carrier rate of Fe3O4 and high encapsulation efficiency of DOX, and a relatively high activity of released DOX within 120 h. In addition, in vitro studies showed that the Fe3O4/DOX/PLGA-PEG nanoparticles were cytocompatibility in NIH 3T3 fibroblast cells culture study while had a special effect on destroying human breast cancer MCF-7 cells compared with pure DOX solution. In vitro studies revealed that the Fe3O4/DOX/PLGA-PEG enabled enhanced T2 contrast magnetic resonance. Overall, our multifunctional Fe3O4/DOX/PLGA-PEG nanoparticles, composed of biocompatible substances and therapeutic/imaging materials, have great potential for the early detection of cancer and accurate drug delivery via the dynamic monitoring using MRI.