Vascular endothelial growth factor-targeted paclitaxel-loaded liposome microbubbles and inhibition of human epidermoid-2 cell proliferation

Evaluation of Liposome-Loaded Microbubbles as a Theranostic Tool in a Murine Collagen-Induced Arthritis Model

Rheumatoid arthritis (RA) is an autoimmune disease characterized by severe inflammation of the synovial tissue. Here, we assess the feasibility of liposome-loaded microbubbles as theranostic agents in a murine arthritis model. First, contrast-enhanced ultrasound (CEUS) was used to quantify neovascularization in this model since CEUS is well-established for RA diagnosis in humans. Next, the potential of liposome-loaded microbubbles and ultrasound (US) to selectively enhance liposome delivery to the synovium was evaluated with in vivo fluorescence imaging. This procedure is made very challenging by the presence of hard joints and by the limited lifetime of the microbubbles. The inflamed knee joints were exposed to therapeutic US after intravenous injection of liposome-loaded microbubbles. Loaded microbubbles were found to be quickly captured by the liver. This resulted in fast clearance of attached liposomes while free and long-circulating liposomes were able to accumulate over time in the inflamed joints. Our observations show that murine arthritis models are not well-suited for evaluating the potential of microbubble-mediated drug delivery in joints given: (i) restricted microbubble passage in murine synovial vasculature and (ii) limited control over the exact ultrasound conditions in situ given the much shorter length scale of the murine joints as compared to the therapeutic wavelength.

Recent Advancements in Liposome-Targeting Strategies for the Treatment of Gliomas: A Systematic Review

Malignant tumors represent some of the most intractable diseases that endanger human health. A glioma is a tumor of the central nervous system that is characterized by severe invasiveness, blurred boundaries between the tumor and surrounding normal tissue, difficult surgical removal, and high recurrence. Moreover, the blood-brain barrier (BBB) and multidrug resistance (MDR) are important factors that contribute to the lack of efficacy of chemotherapy in treating gliomas. A liposome is a biofilm-like drug delivery system with a unique phospholipid bilayer that exhibits high affinities with human tissues/organs (e.g., BBB). After more than five decades of development, classical and engineered liposomes consist of four distinct generations, each with different characteristics: (i) traditional liposomes, (ii) stealth liposomes, (iii) targeting liposomes, and (iv) biomimetic liposomes, which offer a promising approach to promote drugs across the BBB and to reverse MDR. Here, we review the history, preparatory methods, and physicochemical properties of liposomes. Furthermore, we discuss the mechanisms by which liposomes have assisted in the diagnosis and treatment of gliomas, including drug transport across the BBB, inhibition of efflux transporters, reversal of MDR, and induction of immune responses. Finally, we highlight ongoing and future clinical trials and applications toward further developing and testing the efficacies of liposomes in treating gliomas.

A Gastric Cancer Peptide GX1-Modified Nano-Lipid Carriers Encapsulating Paclitaxel: Design and Evaluation of Anti-Tumor Activity

Aim

The aim of this study was to develop a GX1-modified nanostructured lipid carrier (NLCs) and to evaluate its ability to improve the anti-gastric cancer tumor effects of paclitaxel (PTX).

Main Methods

The GX1-modified NLCs were synthesized and loaded with PTX (GX1-PTX-NLCs) by emulsion solvent evaporation technique. The anti-tumor activity and pharmacodynamics were then evaluated by in vitro cell studies and animal experiments.

Key Findings

The GX1-modified NLCs were successfully synthesized and confirmed by ¹H NMR and MALDI-TOF-MS. PTX-loaded NLCs produced particles with average size distribution less than or equal to 222 nm and good drug loading and entrapment efficiency. In vitro studies demonstrated that GX1-PTX-NLCs had a more obvious inhibitory effect on Co-HUVEC cells than PTX and unmodified PTX-NLCs. The cellular uptake results also showed that GX1-PTX-NLCs were largely concentrated in Co-HUVEC cells, and the uptake rates of GX1-PTX-NLCs in Co-HUVEC were higher than those of the free drug and the PTX-NLC. In vivo studies demonstrated that GX1-PTX-NLCs possess strong anti-tumor effect and showed higher tumor growth inhibition and lower toxicity in nude mice.

Significance

These results suggest that GX1-modified NLCs enhanced the anti-tumor activity of PTX and reduced its toxicity effectively. GX1-PTX-NLCs may be considered as a potent drug delivery system for therapy of gastric cancer.