Photo-triggered gadofullerene: enhanced cancer therapy by combining tumor vascular disruption and stimulation of anti-tumor immune responses.

Efficient treatment of primary tumor and preventing cancer metastasis present intriguing alternatives to cancer therapy. Herein, for the first time, we reported the photo-triggered nano-gadofullerene (Gd@C82-Ala, abbreviated Gd-Ala) induced malignant tumor vascular disruption by shortening the light interval between Gd-Ala administration and light illumination, where oxygen in blood vessels was employed efficiently to produce cytotoxic reactive oxygen species (ROS). The produced ROS could not only destroy the tumor cells but also devastate the vascular endothelial cells corresponding to the loss of intercellular junctions and vessels disruption. Notably, the irradiated Gd-Ala could enhance dendritic cells (DCs) maturation, which further secreted tumor necrosis factor-α (TNF-α) and interleukin-12 (IL)-12, and then activated T lymphocytes by up-regulation of cluster of differentiation CD4+ and CD8+ T lymphocytes. Furthermore, the down-regulation of matrix metalloprotein 2 (MMP2) and MMP9 also reduce the rate of tumor metastasis. This work explored a new biomedical application of gadofullerene, thereby providing a smart carbon nanomaterial candidate for tumor ablation and inhibition of cancer metastasis.

Biodegradable, Hydrogen Peroxide, and Glutathione Dual Responsive Nanoparticles for Potential Programmable Paclitaxel Release.

Reactive oxygen species (ROS) and glutathione (GSH) dual responsive nanoparticulate drug delivery systems (nano-DDSs) hold great promise to improve the therapeutic efficacy and alleviate the side effects of chemo drugs in cancer theranosis. Herein, hydrogen peroxide (H2O2) and GSH dual responsive thioketal nanoparticle (TKN) was rationally designed for paclitaxel (PTX) delivery. Compared to other stimuli-sensitive nano-DDSs, this dual responsive DDS is not only sensitive to biologically relevant H2O2 and GSH for on-demand drug release but also biodegradable into biocompatible byproducts after fulfilling its delivering task. Considering the heterogeneous redox potential gradient, the PTX loaded TKNs (PTX-TKNs) might first respond to the extracellular ROS and then to the intracellular GSH, achieving a programmable release of PTX at the tumor site. The selective toxicity of PTX-TKNs to tumor cells with high levels of ROS and GSH was verified both in vitro and in vivo.

RF-assisted gadofullerene nanoparticles induces rapid tumor vascular disruption by down-expression of tumor vascular endothelial cadherin.

The tumor vasculature with unique characteristics offers an attractive target for anti-cancer therapy. Herein, we put forward a novel antitumor therapeutic mechanism based on the gadofullerene nanocrystals (GFNCs), the agent we have previously shown to efficiently disrupt tumor vasculature by size-expansion with assistance of radiofrequency (RF). However, the tumor vascular disrupting mechanism of RF-assisted GFNCs treatment was not further studied. In the present work, a rapid tumor blood flow shutdown has been observed by the vascular perfusion imaging in vivo and vascular damages were evident 6 h after the RF-assisted GFNCs treatment. Importantly, a significant down-expression of tumor vascular endothelial cadherin (VE-cadherin) treated by RF-assisted GFNCs was further investigated, which caused vascular collapse, blood flow shut-down and subsequent tumor hemorrhagic necrosis. These findings set forth a systematic mechanism on the superior anti-tumor efficiency by RF-assisted GFNCs treatment.

Amino acid functionalized gadofullerene nanoparticles with superior antitumor activity via destruction of tumor vasculature in vivo.

Researchers have been puzzled of the therapy of malignant tumors and the current therapeutic strategies are always accompanied by toxicity or side effects. Developing efficient nanodrugs could reduce the dosage and greatly improve the therapeutic effects in cancer treatments. Here we initially reported a novel kind of gadofullerene nanoparticles functionalized with amino acid (ß-alanine), which exhibited a superior antitumor activity in hepatoma H22 models via a novel therapeutic mechanism. The involvement of ß-alanine improved the tumor inhibition rate up to 76.85% for a single treatment by strengthening the interaction with radiofrequency (RF) and extending blood circulation time. It realized a highly antivascular treatment to cut off the nutrient supply of tumor cells by physically destroying the abnormal tumor blood vessels assisted by RF. In situ and real-time observation of the vascular change was conducted using the dorsal skin fold chamber model, which corresponded to the erythrocyte diapedesis in histopathological examination. The ultrastructural changes of vascular endothelial cells were further investigated by environmental scanning electron microscopy and transmission electron microscopy. Long-term toxicity evaluation showed that the GF-Ala nanoparticles could be eliminated from the mice after several days and no obvious toxicity was found to the main organs. All these encouraging results suggest GF-Ala nanoparticles are valuable for the significant therapeutic potential with high-efficacy and low-toxicity.

Fullerene/photosensitizer nanovesicles as highly efficient and clearable phototheranostics with enhanced tumor accumulation for cancer therapy.

A novel phototheranostic platform based on tri-malonate derivative of fullerene C70 (TFC70)/photosensitizer (Chlorin e6, Ce6) nanovesicles (FCNVs) has been developed for effective tumor imaging and treatment. The FCNVs were prepared from amphiphilic TFC70-oligo ethylene glycol -Ce6 molecules. The developed FCNVs possessed the following advantages: (i) high loading efficiency of Ce6 (up to ∼57 wt%); (ii) efficient absorption in near-infrared light region; (iii) enhanced cellular uptake efficiency of Ce6 in vitro and in vivo; (iv) good biocompatibility and total clearance out from the body. These unique properties suggest that the as-prepared FCNVs could be applied as an ideal theranostic agent for simultaneous imaging and photodynamic therapy of tumor. This finding may provide a good solution to highly efficient phototheranostic applications based on fullerene derivatives fabricated nanostructures.

A Versatile and Clearable Nanocarbon Theranostic Based on Carbon Dots and Gadolinium Metallofullerene Nanocrystals.

Nanocarbons such as carbon nanotubes, graphene derivatives, and carbon nanohorns have illustrated their potential uses as cancer theranostics owing to their intrinsic fluorescence or NIR absorbance as well as superior cargo loading capacity. However, some problems still need to be addressed, such as the fates and long-term toxicology of different nanocarbons in vivo and the improvement of their performance in various biomedical imaging-guided cancer therapy systems. Herein, a versatile and clearable nanocarbon theranostic based on carbon dots (CDs) and gadolinium metallofullerene nanocrystals (GFNCs) is first developed, in which GFNCs enhance the tumor accumulation of CDs, and CDs enhance the relaxivity of GFNCs, leading to an efficient multimodal imaging-guided photodynamic therapy in vivo without obvious long-term toxicity. Furthermore, biochemical analysis reveals that the novel nanotheranostic can harmlessly eliminate from the body in a reasonable period of time after exerting diagnostic and therapeutic function.

Synergistic Effect of Human Serum Albumin and Fullerene on Gd-DO3A for Tumor-Targeting Imaging.

A macromolecular magnetic resonance imaging (MRI) contrast agent was successfully synthesized by conjugating the gadolinium/1,4,7,10-tetraazacyclododecane-1,4,7-tetracetic acid complex (Gd-DO3A) with 6,6-phenyl-C61 butyric acid (PC61BA) and upon further modification with human serum albumin (HSA). The final product, PC61BA-(Gd-DO3A)/HSA, has a high stability and exhibits a much higher relaxivity (r1 = 89.1 mM(-1) s(-1) at 0.5 T, 300 K) than Gd-DO3A (r1 = 4.7 mM(-1) s(-1)) does under the same condition, producing the synergistic positive effect of HSA and C60 on the relaxivity of Gd-DO3A. The in vivo MR images of PC61BA-(Gd-DO3A)/HSA-treated tumor-bearing mice show strong signal enhancement for the tumor area due to the enhanced permeability and retention effect. The maximum accumulation of PC61BA-(Gd-DO3A)/HSA at the tumor site was achieved at 4 h postinjection, which may guide surgery. The results from the hematology and histological observations indicate that PC61BA-(Gd-DO3A)/HSA has no obvious toxicity in vivo. These unique properties of PC61BA-(Gd-DO3A)/HSA enable them to be highly efficient for tumor-targeting MRI in vivo, possibly providing a good solution for tumor diagnosis.