Cancer is among the most dreadful fatal diseases globally, and the efficacy of recent chemotherapeutic approaches is limited due to many related drawbacks. The major limitation associated with cancer chemotherapy is the poor aqueous solubility of most of the anticancer drugs, development of multidrug resistance, low bioavailability, small plasma half-life, and serious side effects to healthy tissues due to unspecific distribution of chemotherapeutic drugs. Advancement in nanoscience provides the means of specific and selective targeting of cancer cells. Chitosan, one of the naturally occurring biocompatible and mucoadhesive biopolymers that have been widely used in recent years for the effective delivery of anti-cancer drugs at the target site. Chitosan nanoparticles can encapsulate both hydrophilic and lipophilic chemotherapeutic drugs, proteins/peptides as well as different genetic materials like DNA, miRNA, siRNA, etc. in their polymeric matrix. Due to the unique polymeric matrix, these nanoparticles improve the solubility as well as the stability of encapsulated molecules in the biological system. Chitosan nanoparticles can improve the pharmacokinetic profile as well as the therapeutic efficacy of encapsulated drugs by controlling the release rates and targeted delivery process. These nanoparticles selectively deliver the encapsulated drugs to desired sites through passive or active targeting mechanisms thereby decrease the undesirable side-effects. The surface of chitosan nanoparticles can be modified with different ligands like antibodies, proteins, peptides, polysaccharides, and nucleic acids to achieve selective targeting. This review will provide a state-of-the-art perspective on recent development in chitosan-nanoparticles for smart anti-cancer therapeutic delivery. Graphical Abstract

Azacitidine (AZA), an inhibitor of DNA methyltransferase, is a commonly recognized drug used in clinical treatment for myelodysplastic syndrome and breast cancer. Due to higher aqueous solubility and negative log P of AZA causes poor cancer cell permeation and controlled release. The objective of the present study was to formulate and optimize AZA-loaded liposome (AZA-LIPO) for breast cancer chemotherapy by using Box Behnken design (BBD) and in vitro evaluation using MCF-7 cells. AZA-LIPO were prepared using a thin film hydration technique and characterization study was performed by using FTIR and DSC. The prepared formulations were optimized using BBD and the optimized formulation was further subjected for particle size, surface charges, polydispersity index (PDI), drug loading, entrapment efficiency, TEM, XRD, in-vitro drug release and hemolytic toxicity. The mean particle size of optimized AZA-LIPO was 127 nm. Entrapment efficiency and drug loading of AZA-LIPO was found to be 85.2% ± 0.5 and 6.82 ± 1.6%, respectively. Further, in vitro drug release study showed preliminary burst release in 2 h followed by a sustained release for 36 h in phosphate buffer at different pH (4.0, 5.5, and 7.4) as compared to free drug. Drug release was found to be pH dependent, as the pH was increased, the drug release rate was found to be low. Time-dependent cell viability assay exhibited significant higher cell viability and higher internalization than free AZA in MCF-7 cells. AZA-LIPO were more effective than the free AZA in reducing Bcl2 expression, while increasing pro-apoptotic Bax and caspase-3 activity. The result showed that the formulated biocompatible AZA-LIPO nano-formulations may be used as an efficient anti-cancer drug delivery system for the treatment of breast cancer after establishing preclinical and clinical studies.

Insulin-dependent diabetic patients have to count on the administration of painful and discomforting insulin injections. However, inadequate insulin absorption and the risk of insulin level escalation in the blood are some disadvantages associated with insulin therapy. Thus, the current study intends to formulate insulin-loaded chitosan nanoparticles for refining the systemic absorption of insulin via the ocular route. Insulin-loaded chitosan nanoparticles were prepared by the ionotropic gelation method and characterized for various parameters. Optimized insulin loaded nanoparticles (C4T4I4) were positively charged with a particle size of 215 ± 2.5 nm and showed 65.89 ± 4.3% entrapment efficiency. The in vitro drug release exhibited sustained release of insulin, where 77.2 ± 2.1% of release was observed after 12 h and leads to an assumption of the non-Fickian diffusion release mechanism. The permeation study discloses good mucoadhesive and better permeation properties of insulin loaded nanoparticles compared to free Insulin. No significant difference was observed in the size of particles after six months of storage, signifying their adequate stability. Nanoparticles were found to be non-irritant to ocular tissues and exhibited prominent blood glucose level reduction in vivo. The outcomes of this study suggested that the chitosan nanoparticulate system could act as a prominent carrier system for insulin with enhanced stability and efficacy.

Introduction: Cancer immunotherapy is a fast-growing field that has achieved tremendous progress in recent years. It is one of the most potent tools that can activate the immune system against cancer. Nevertheless, the development of safe and effective vaccines to overcome emerging new disease remains challenging since several emerging antigens are poorly immunogenic. Nanotechnology has provided a realistic resolution for the drawback of traditional cancer immunotherapy. Area covered: This review discusses different cancer immunotherapy approaches focusing on recent advancements in nanomedicine-based cancer immunotherapy. The literature review method includes inclusion and exclusion criteria to categorize important articles. The literature survey was carried out using PubMed, Google Scholar, Scopus, and the Saudi digital library. Expert opinion: In the last two decades, the development and application of nanoparticles incorporating antigen/adjuvant in cancer immunotherapy have experienced rapid growth. Soon, progressively multifaceted nanovaccines presenting different antigens and co-delivered with antigens will be clinically translated. Better understanding and improved knowledge of nanomedicines-based delivery approaches and immunostimulatory action, and in-vivo biodistribution would inevitably facilitate the altruistic design of cancer nanovaccine for humankind.