Advances in Polymeric Micelles: Responsive and Targeting Approaches for Cancer Immunotherapy in the Tumor Microenvironment

Advanced therapeutic strategies using Thermo-sensitive chitosan/pectin hydrogel in the treatment of multiple cancers

Current cancer therapies including immunotherapy and chemotherapy produce adverse side effects that demand improved drug distribution methods. Research shows that thermosensitive chitosan/pectin-based hydrogels serve as an effective platform technology for drug delivery during cancer therapy because of their ability to control drug release at specific locations. The hydrogels perform temperature-triggered sol-gel phase shifts which enables prolonged drug delivery together with minimal toxic side effects. The biocompatible and biodegradable properties of these materials enable solutions against drug resistance and tumour heterogeneity challenges. Studies have demonstrated that these hydrogels enhance drug bioavailability, extend circulation time, and improve tumour targeting, leading to increased therapeutic efficacy and reduced systemic toxicity. Their ability to sustain drug release and penetrate tumour microenvironments makes them a promising strategy for overcoming drug resistance and tumour heterogeneity. Their ability to reproduce native tissue properties poses challenges that scientists must address through improved structural optimization approaches. The combination of latest nanotechnology innovations and interdisciplinary studies has sped up the creation of chitosan/pectin hydrogels for cancer treatment applications. This review highlights the significant advancements and demonstrated effectiveness of thermosensitive chitosan/pectin hydrogels in cancer treatment by exploring their design parameters alongside their drug release behaviour while discussing their potential medical applications.

Personalized nanovaccines for treating solid cancer metastases

Cancer vaccines have garnered attention as a potential treatment for cancer metastases. Nevertheless, the clinical response rate to vaccines remains < 30%. Nanoparticles stabilize vaccines and improve antigen recognition and presentation, resulting in high tumor penetration or accumulation, effective co-distribution of drugs to the secondary lymphatic system, and adaptable antigen or adjuvant administration. Such vaccine-like nanomedicines have the ability to eradicate the primary tumors as well as to prevent or eliminate metastases. This review examines state-of-the-art nanocarriers developed to deliver tumor vaccines to metastases, including synthetic, semi-biogenic, and biogenic nanosystems. Moreover, it highlights the physical and pharmacological properties that enhance their anti-metastasis efficiency. This review also addresses the combination of nanovaccines with cancer immunotherapy to target various steps in the metastatic cascade, drawing insights from preclinical and clinical studies. The review concludes with a critical analysis of the challenges and frameworks linked to the clinical translation of cancer nanovaccines.

Pioneering Advances and Innovative Applications of Mesoporous Carriers for Mitochondria-Targeted Therapeutics

Mitochondria, known as the cell's powerhouse, play a critical role in energy production, cellular maintenance, and stemness regulation in non-cancerous cells. Despite their importance, using drug delivery systems to target the mitochondria presents significant challenges due to several barriers, including cellular uptake limitations, enzymatic degradation, and the mitochondrial membranes themselves. Additionally, barriers in the organs to be targetted, along with extracellular barriers formed by physiological processes such as the reticuloendothelial system, contribute to the rapid elimination of nanoparticles designed for mitochondrial-based drug delivery. Overcoming these challenges has led to the development of various strategies, such as molecular targeting using cell-penetrating peptides, genomic editing, and nanoparticle-based systems, including porous carriers, liposomes, micelles, and Mito-Porters. Porous carriers stand out as particularly promising candidates as drug delivery systems for targeting the mitochondria due to their large pore size, surface area, and ease of functionalisation. Depending on the pore size, they can be classified as micro-, meso-, or macroporous and are either ordered or non-ordered based on both size and pore uniformity. Several methods are employed to target the mitochondria using porous carriers, such as surface modifications with polyethylene glycol (PEG), incorporation of targeting ligands like triphenylphosphonium, and capping the pores with gold nanoparticles or chitosan to enable controlled and triggered drug delivery. Photodynamic therapy is another approach, where drug-loaded porous carriers generate reactive oxygen species (ROS) to enhance mitochondrial targeting. Further advancements have been made in the form of functionalised porous silica and carbon nanoparticles, which have demonstrated potential for effective drug delivery to mitochondria. This review highlights the various approaches that utilise porous carriers, specifically focusing on silica-based systems, as efficient vehicles for targeting mitochondria, paving the way for improved drug delivery strategies in mitochondrial therapies.

Tumor Microenvironment-Responsive Drug Delivery Based on Polymeric Micelles for Precision Cancer Therapy: Strategies and Prospects

In clinical practice, drug therapy for cancer is still limited by its inefficiency and high toxicity. For precision therapy, various drug delivery systems, including polymeric micelles self-assembled from amphiphilic polymeric materials, have been developed to achieve tumor-targeting drug delivery. Considering the characteristics of the pathophysiological environment at the drug target site, the design, synthesis, or modification of environmentally responsive polymeric materials has become a crucial strategy for drug-targeted delivery. In comparison to the normal physiological environment, tumors possess a unique microenvironment, characterized by a low pH, high reactive oxygen species concentration, hypoxia, and distinct enzyme systems, providing various stimuli for the environmentally responsive design of polymeric micelles. Polymeric micelles with tumor microenvironment (TME)-responsive characteristics have shown significant improvement in precision therapy for cancer treatment. This review mainly outlines the most promising strategies available for exploiting the tumor microenvironment to construct internal stimulus-responsive drug delivery micelles that target tumors and achieve enhanced antitumor efficacy. In addition, the prospects of TME-responsive polymeric micelles for gene therapy and immunotherapy, the most popular current cancer treatments, are also discussed. TME-responsive drug delivery via polymeric micelles will be an efficient and robust approach for developing clinical cancer therapies in the future.