Nanoscale metal–organic frameworks (nMOFs) have attracted much attention as emerging porous materials as drug delivery carriers. Appropriate surface modification of them can greatly improve stability and introduce biocompatibility and cancer targeting functionality into drug delivery systems. Herein, we prepared nano-sized MIL-101(Fe)-N 3 and loaded anticancer drug doxorubicin (DOX) into it. The synthetic polymer layer Alkyne-PLA-PEG was then attached to the F3 peptide (labeled as Alkyne-PLA-PEG-F3), and the surface of DOX/MIL-101(Fe)-N 3 was covalently modified with it to obtain DOX/MIL-101-PLA-PEG-F3. Nano-sized MIL-101(Fe)-N 3 has high drug loading capacity and the modification of MIL-101(Fe)-N 3 by polymer Alkyne-PLA-PEG not only improved the dispersion, but also avoided the sudden release of the drugs and increased the biocompatibility of nanocarriers. The F3 peptide introduced into the nanocarriers also enabled it to specifically target tumor tissues and achieved active targeted drug delivery. As a nucleolin-mediated endocytosis drug delivery system, DOX/MIL-101-PLA-PEG-F3 can not only deliver anticancer drugs to tumors accurately, but also participate in Fenton-like reaction to generate hydroxyl radicals (•OH) for chemodynamic therapy (CDT), thus enabling combination therapy. It holds great promise as drug candidates to reduce systemic toxicity and improve the efficacy of cancer treatment.
Nanoscale metal–organic frameworks (nMOFs) are a unique type of hybrid materials, which are broadly applicable as cargo delivery systems. However, the relatively low material stability and insufficient cancer cell interacting capacity have limited nMOFs’ applications in cancer theranostics. Herein, a zirconium-based nMOF UiO-66-N3 was synthesized, and its surface was covalently functionalized with alkyne-containing polyethylene glycol (PEG) via the azide–alkyne click chemistry. After that, F3 peptide was attached for targeting of cancer cells (the material was denoted as UiO-66-PEG-F3). Doxorubicin (DOX) served as a therapeutic drug and a fluorescent label in this study, and it was transported into UiO-66-PEG conjugates with sufficient drug loading efficiency. pH-responsive release of DOX from UiO-66 conjugates was witnessed. The structural integrity of UiO-66-N3 was maintained post the surface modification process. Flow cytometry and confocal fluorescence microscopy revealed that DOX/UiO-66-PEG-F3 had stronger accumulation in MDA-MB-231 cells (nucleolin+) compared with DOX/UiO-66-PEG. In order to track the pharmacokinetic behavior (organ distribution profile) in vivo, the positron-emitting zirconium-89 (89Zr) was incorporated into UiO-66-N3. Similar PEGylation and F3 peptide conjugation resulted in the formation of 89Zr-UiO-66-PEG-F3. Serial positron emission tomography (PET) imaging demonstrated that the preferential accumulation of 89Zr-UiO-66-PEG-F3 in MDA-MB-231 tumors, and their liver clearance was faster than PEGylated UiO-66 using noncovalent methods. Thus, the PEGylated nMOFs using covalent strategies may find broad application in future cancer theranostics.
Yudi Deng,Zhijie Jiang,Yincheng Jin,Jianan Qiao,Shan Yang,Hui Xiong,Jing Yao
Detrimental tumor microenvironment (TME) relies on distorted tumor vasculature for further tumor expansion. Vascular normalization therapy partly improves TME through vessel repairing, while these therapies enter an unbreakable Möbius ring due to each attempt hindered by pro-angiogenic factors from TME, leading to limited duration and extent of vascular normalization. Here, we developed a nanosystem including FLG and MAR/MPA nanodrugs to regulate both tumor vasculature and TME. FLG nanodrugs were constructed by connecting VEGF/VEGFR2 inhibitory low molecular weight heparin and gambogic acid with F3 peptide decoration for directly regulating on vascular endothelial cells and inducing vascular normalization. Meanwhile, MAR/MPA nanodrugs encapsulating CCL5/CCR5 blocker maraviroc were designed to restrict cytokine functions of angiogenesis and TME deterioration, contributing to vasculature repairing and TME reconstruction. Our results demonstrated this combined nanosystem synergistically induced vascular normalization window lasting 9 days and restored vascular permeability and oxygen supply in Panc-1 tumor. Furthermore, in melanoma, our nanosystem achieved immune improvements with increased infiltration of CD4 + and CD8 + T cells in a remodeled TME. The two nanodrugs assisting each other in terms of both vascular repairing and TME improvements successfully reversed the vicious crosstalk to a positive one, achieving overall TME remodeling and promoting therapeutic efficiency.