Surface functionalization of liposomes can play a key role in overcoming the current limitations of nanocarriers to treat solid tumors, i.e., biological barriers and physiological factors. The phospholipid vesicles (liposomes) containing anticancer agents produce fewer side effects than non-liposomal anticancer formulations, and can effectively target the solid tumors. This article reviews information about the strategies for targeting of liposomes to solid tumors along with the possible targets in cancer cells, i.e., extracellular and intracellular targets and targets in tumor microenvironment or vasculature. Targeting ligands for functionalization of liposomes with relevant surface engineering techniques have been described. Stimuli strategies for enhanced delivery of anticancer agents at requisite location using stimuli-responsive functionalized liposomes have been discussed. Recent approaches for enhanced delivery of anticancer agents at tumor site with relevant surface functionalization techniques have been reviewed. Finally, current challenges of functionalized liposomes and future perspective of smart functionalized liposomes have been discussed.

Effective therapy for Alzheimer’s disease is a major challenge in the pharmaceutical sciences. There are six FDA approved drugs (e.g., donepezil, memantine) that show some effectiveness; however, they only relieve symptoms. Two factors hamper research. First, the cause of Alzheimer’s disease is not fully understood. Second, the blood-brain barrier restricts drug efficacy. This review summarized current knowledge relevant to both of these factors. First, we reviewed the pathophysiology of Alzheimer’s disease. Next, we reviewed the structural and biological properties of the blood-brain barrier. We then described the most promising drug delivery systems that have been developed in recent years; these include polymeric nanoparticles, liposomes, metallic nanoparticles and cyclodextrins. Overall, we aim to provide ideas and clues to design effective drug delivery systems for penetrating the blood-brain barrier to treat Alzheimer’s disease.

Crocetin (CRT) has shown various neuroprotective effects such as antioxidant activities and the inhibition of amyloid β fibril formation, and thus is a potential therapeutic candidate for Alzheimer's disease (AD). However, poor water solubility and bioavailability are the major obstacles in formulation development and pharmaceutical applications of cRt. in this study, a novel water-soluble cRt-γcyclodextrin inclusion complex suitable for intravenous injection was developed. the inclusion complex was nontoxic to normal neuroblastoma cells (N2a cells and SH-SY5Y cells) and AD model cells (7PA2 cells). furthermore, it showed stronger ability to downregulate the expression of c-terminus fragments and level of amyloid β in 7PA2 cell line as compared to the CRT free drug. Both inclusion complex and CRT were able to prevent SH-SY5Y cell death from H 2 o 2-induced toxicity. the pharmacokinetics and biodistribution studies showed that cRt-γ-cyclodextrin inclusion complex significantly increased the bioavailability of cRt and facilitated cRt crossing the blood-brain barrier to enter the brain. this data shows a water-soluble γ-cyclodextrin inclusion complex helped to deliver cRt across the blood-brain barrier. this success should fuel further pharmaceutical research on cRt in the treatment for AD, and it should engender research on γ-cyclodextrin with other drugs that have so far not been explored. Alzheimer's disease (AD) is an irreversible neurodegenerative disease which cannot be cured by any therapeutic approaches up to now 1. As the number of AD patients increases, the need to develop safe, effective drugs for AD therapy becomes increasingly urgent. In traditional herbal medicine, several plants have been used to treat the symptoms of neurodegenerative diseases 2,3. Crocetin (CRT) is an active compound isolated from the fruits of gardenia (Gardenia jasminoides Ellis) and the stigmas of saffron (Crocus sativus L.) 4. Various pharmacological activities of CRT have been reported. CRT can inhibit amyloid β (Aβ) fibril formation, destabilize pre-formed Aβ fibrils and improve Aβ degradation in vitro 5,6. CRT can also reduce Aβ 1-42-induced neurotoxicity by attenuating oxidative stress in murine hippocampal cells 7. Furthermore, CRT can reduce the production of various neurotoxic molecules from neuron, such as lipopolysaccharide (LPS)-induced nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and reactive oxygen species (ROS), which provided strong protection from neuronal cell death 8,9. Moreover, CRT has been proven to cross the blood-brain barrier (BBB) limitedly after administration 10. The mentioned properties of CRT indicate that it may be a potentially useful candidate for AD treatment. In terms of its chemical structure (Fig. 1A), CRT contains two carboxylic acid groups at each end of a polyene chain. However, CRT is insoluble in water in the physiological range (0.0056 g/L); it can only slightly dissolve in pyridine, dimethyl sulfoxide or aqueous alkali solutions at pH above 9 11. Poor solub...

Purpose: Lung cancer has a high incidence rate worldwide with a 5-year survival rate of 18%, and is the leading cause of cancer-related deaths. The aim of this study is to augment therapeutic efficacy of quercetin (QR) for lung cancer therapy by targeting transferrin receptors, which are overexpressed and confined to tumor cells. Methods: In this study, T7 surface-functionalized liposomes loaded with QR (T7-QR-lip) having different T7 peptide densities (0.5%, 1% and 2%) were prepared by the film hydration method. T7 surface-functionalized liposomes were characterized and evaluated in terms of in vitro cytotoxicity and cellular uptake, 3D tumor spheroid penetration and inhibition capabilities, in vivo biodistribution and therapeutic efficacy in mice with orthotopic lung-tumor implantation by fluorescent and bioluminescent imaging via pulmonary administration. Results: In vitro, 2% T7-QR-lip exhibited significantly augmented cytotoxicity (~3-fold), higher apoptosis induction and S-phase cell-cycle arrest. A prominent peak right-shift and enhanced mean fluorescence intensity was observed in A549 cells treated with T7 Coumarin-6 liposomes (T7-Cou6-lip), confirming the target specificity of T7 targeted liposomes; while, after treatment with T7-QR-lip and non-targeted QR-lip, no significant difference was observed in cellular uptake and in vitro cytotoxicity studies in MRC-5 (normal lung fibroblast) cells. T7-Cou6-lip showed higher fluorescence intensity in A549 cells and a significantly deeper penetration depth of 120 µm in the core of the tumor spheroids and T7-QR-lip produced significantly higher tumor-spheroid growth inhibition. The in vivo biodistribution study via pulmonary delivery of T7 1,1’-dioctadecyltetramethyl-indotricarbocyanine iodide liposomes demonstrated liposome accumulation in the lungs and sustained-release behavior up to 96 h. Further, T7-QR-lip significantly enhanced the anticancer activity of QR and lifespan of mice ( p <0.01, compared with saline) in orthotopic lung tumor-bearing mice via pulmonary administration. Conclusion: T7 surface-functionalized liposomes provide a potential drug delivery system for a range of anticancer drugs to enhance their therapeutic efficacy by localized (pulmonary) administration and targeted delivery.

Cancer is a global health challenge. There are drawbacks to conventional chemotherapy such as poor bioavailability, development of drug resistance and severe side effects. Novel drug delivery system may be an alternative to optimize therapeutic effects. When such systems consist of natural materials, they offer important advantages: they are usually highly biocompatible, biodegradable, nontoxic and nonimmunogenic. Furthermore, natural materials can be easily modified for conjugation with a wide range of therapeutic agents and targeting ligands, according to the therapeutic purpose. This article reviews different natural ingredients and their applications in drug delivery systems for cancer therapy. Firstly, an overview of the polysaccharides and protein-based polymers that have been extensively investigated for drug delivery are described. Secondly, recent advances in using various natural ingredient-based polymeric nanoparticles for cancer therapy are reviewed. The characteristics of these delivery systems are summarized, followed by a discussion of future development and clinical potential. This review aims to summarize current knowledge and provide a basis for developing effective tailor-made formulations for cancer therapy in the future.