Functionalized graphene oxide (CGO–cRGDyK/POLO) nanosheets were designed and developed for targeted drug delivery to integrin expression. The anticancer drug cambretastain A4 (CA4) was conjugated onto the CGO–cRGDyK/POLO nanosheets. The tumor targeting ligands, cyclic arginine–glycine–aspartic acid–tyrosine–lysine pentapeptides (cRGDyK), were conjugated to carboxylated graphene oxide (CGO) nanosheets, and poloxamer 188 (POLO) was rendered to make the CGO–cRGDyK nanosheets stable. The CGO–cRGDyK/POLO nanosheets exhibited good cytocompatibility, high CA4-loading capacity (0.6872 ± 0.0121 mg mg−1) via π–π stacking or hydrophobic interactions, and controlled release in vitro. The MTT assays showed that the CGO–cRGDyK nanosheets had greater antitumor effects on Hela cells than CGO/POLO nanosheets but lower cytotoxicity on the L02 cells than free CA4. In addition, the cellular uptake of CGO–cRGDyK/POLO nanosheets was increased significantly in human umbilical vein endothelial cells (the integrins-overexpressed cells) compared to the normal L02 cells. Thus, the CGO–cRGDyK/POLO nanosheets are an appealing platform for cancer chemotherapy.
This study aimed to prepare efficient cRGDyK peptide-decorated micelles for the targeted therapy of non-small-cell lung cancer (NSCLC). An amphiphilic copolymer N -succinyl-palmitoyl-chitosan (SPCS) was synthesized and characterized. cRGDyK peptide is a ligand that can target tumors via specific binding integrin receptor overexpressed on tumor neovascularization and cells. cRGDyK-functionalized SPCS micelles loaded with paclitaxel (PTX/cRGDyK-SPCS) were prepared by film dispersion method and then characterized according to morphology, size, and zeta potential . PTX/cRGDyK-SPCS micelles presented pH-triggered drug release behavior under acidic conditions. The accumulation of micelles detected by laser confocal fluorescence microscopy and flow cytometry showed that cRGDyK-SPCS micelles were easily taken up by A549 cells marked with the luciferase gene (luc-A549). Meanwhile, co-localization of the micelles and lysosomes was recorded dynamically using a live cell station. MTT assays and cell apoptosis studies revealed that cell viability was significantly inhibited by PTX/cRGDyK-SPCS micelles. More importantly, in vivo animal studies showed that cRGDyK-SPCS micelles mainly accumulated in the orthotopic tumor site. PTX/cRGDyK-SPCS micelles exhibited better anti-tumor activity in subcutaneous and orthotopic lung tumors compared with PTX/SPCS micelles and Taxol ® . These results suggested that PTX/cRGDyK-SPCS micelles had better cancer targeting capacity and superior anti-tumor efficacy. Thus, these micelles have great potential as novel carriers in delivering anti-tumor drugs.
Photodynamic therapy (PDT) has increasingly become an efficient and attractive cancer treatment modality based on reactive oxygen species (ROS) that can induce tumor death after irradiation with ultraviolet or visible light. Herein, to overcome the limited tissue penetration in traditional PDT, a novel near-infrared (NIR) light-activated NaScF 4 : 40% Yb, 2% [email protected] 2 upconversion nanoparticle (rUCNP) is successfully designed and synthesized. Chlorin e6, a photosensitizer and a chelating agent for Mn 2+ , is loaded into human serum albumin (HSA) that further conjugates onto rUCNPs. To increase the ability to target glioma tumor, an acyclic Arg–Gly–Asp peptide (cRGDyK) is linked to [email protected] (Ce6-Mn). This nanoplatform enables efficient adsorption and conversion of NIR light (980 nm) into bright red emission (660 nm), which can trigger the photosensitizer Ce6-Mn complex for PDT and T 1 -weighted magnetic resonance imaging (T 1 -weighted MRI) for glioma diagnosis. Our in vitro and in vivo experiments demonstrate that NIR light-activated and glioma tumor-targeted PDT can generate large amounts of intracellular ROS that induce U87 cell apoptosis and suppress glioma tumor growth owing to the deep tissue penetration of irradiated light and excellent tumor-targeting ability. Thus, this nanoplatform holds potential for applications in T 1 -weighted MRI diagnosis and PDT of glioma for antitumor therapy. Statement of Significance A near-infrared (NIR) light-activated nanoplatform for photodynamic therapy (PDT) was designed and synthesized. The Red-to-Green (R/G) ratio of NaScF 4 : 40% Yb, 2% Er almost reached 9, a value that was much higher than that of a traditional Yb/Er-codoped upconversion nanoparticle (rUCNP). By depositing a CaF 2 shell, the red-emission intensities of the rUCNPs were seven times strong as that of NaScF 4 : 40% Yb, 2% Er. The enhanced red-emitting rUCNPs could be applied in many fields such as bioimaging, controlled release, and real-time diagnosis. The nanoplatform had a strong active glioma-targeting ability, and all results achieved on subcutaneous glioma demonstrated that our NIR light-activated red-emitting upconverting nanoplatform was efficient for PDT. By loading Ce6-Mn complex into [email protected] , the nanoplatform could be used as a T 1 -weighted magnetic resonance imaging agent for tumor diagnosis.