Tumor is a serious threat to human health, with extremely high morbidity and mortality rates. However, tumor treatment is challenging, and the development of antitumor drugs has always been a significant research focus. Plant polysaccharides are known to possess various biological activities. They have many pharmacological properties such as immunomodulation, antitumor, antiviral, antioxidative, antithrombotic, and antiradiation effects, reduction of blood pressure and blood sugar levels, and protection from liver injury. Among these effects, the antitumor effect of plant polysaccharides has been widely studied. Plant polysaccharides can inhibit tumor proliferation and growth by inhibiting tumor cell invasion and metastasis, inducing cell apoptosis, affecting the cell cycle, and regulating the tumor microenvironment. They also have the characteristics of safety, high efficiency, and low toxicity, which can alleviate, to a certain extent, the adverse reactions caused by traditional tumor treatment methods such as surgery, radiotherapy, and chemotherapy. Therefore, this paper systematically summarizes the direct antitumor effects of plant polysaccharides, their regulatory effects on the tumor microenvironment, and intervening many common high-incidence tumors in other ways. It also provides data support for the administration of plant polysaccharides in modern tumor drug therapy, enabling the identification of new targets and development of new drugs for tumor therapy.

Cancer remains one of the most prominent global health concerns, posing a substantial threat to public health. Millions of people die from cancer each year, and many cancer types remain incurable at present. Conventional cancer treatments, including surgery, chemotherapy, radiotherapy, and immunotherapy, often fail to achieve optimal clinical outcomes and are frequently associated with severe trauma and adverse effects. Consequently, there is an urgent need to develop novel therapeutic strategies to address these limitations. Hydrogels have been widely utilised as platforms for loading drugs, proteins, DNA, and stem cells in biomedical tissue repair and cancer therapy. Through modification of their physicochemical properties and functions, hydrogels can be endowed with responsiveness to multiple stimuli. In recent years, stimuli-responsive hydrogels (also known as smart-responsive hydrogels), as novel drug delivery systems, have demonstrated remarkable efficacy in cancer treatment. Stimuli-responsive hydrogels are capable of altering their mechanical properties, swelling behaviour, hydrophilicity, bioactivity, and molecular permeability in response to endogenous stimuli (including pH, ROS, and temperature) and exogenous stimuli (including light, ultrasound, and magnetic fields). This review highlights recent advances and applications of responsive hydrogels triggered by endogenous stimuli (including pH, ROS, and temperature) and exogenous stimuli (including light, ultrasound, and magnetic force) in cancer drug delivery and treatment. Finally, the current application limitations and future prospects of smart-responsive hydrogels are summarised.

The rapid pace of modern life has contributed to a significant decline in sleep quality, which has become an urgent global public health issue. Melatonin, an endogenous hormone that regulates circadian rhythms, is vital in maintaining normal sleep cycles. While oral melatonin supplementation is widely used, transdermal delivery systems present advantages that include the avoidance of first-pass metabolism effects and enhanced bioavailability. In this study, a novel melatonin transdermal delivery system was successfully developed using a thermosensitive poly(N-vinylcaprolactam) [p(NVCL)]-based carrier. The p(NVCL) polymer was synthesized through free radical polymerization and characterized for its structural properties and phase transition temperature, in alignment with skin surface conditions. Orthogonal optimization experiments identified 3% azone, 3% menthol, and 4% borneol as the optimal enhancer combination for enhanced transdermal absorption. The formulation demonstrated exceptional melatonin loading characteristics with high encapsulation efficiency and stable physicochemical properties, including an appropriate pH and optimal moisture content. Comprehensive in vivo evaluation using normal mouse models revealed significant sleep quality improvements, specifically a shortened sleep latency and extended non-rapid eye movement sleep duration, with elevated serum melatonin and serotonin levels. Safety assessments including histopathological examination, biochemical analysis, and 28-day continuous administration studies confirmed excellent biocompatibility with no adverse reactions or systemic toxicity. Near-infrared fluorescence imaging provided direct evidence of enhanced transdermal absorption and superior biodistribution compared to oral administration. These findings indicate that the p(NVCL)-based melatonin transdermal gel system offers a safe, effective and convenient non-prescription option for sleep regulation, with promising potential for clinical translation as a consumer sleep aid.

Atherosclerosis remains a leading cause of cardiovascular mortality despite advances in pharmacological and interventional therapies. Current treatment approaches face limitations including systemic side effects, inadequate local drug delivery, and restenosis following vascular interventions. Gel-based technologies offer unique advantages through tunable mechanical properties, controlled degradation kinetics, high drug-loading capacity, and potential for stimuli-responsive therapeutic release. This review examines gel platforms across multiple scales and applications in atherosclerosis research and intervention. First, gel-based in vitro models are discussed. These include hydrogel matrices simulating plaque microenvironments, three-dimensional cellular culture platforms, and microfluidic organ-on-chip devices. These devices incorporate physiological flow to investigate disease mechanisms under controlled conditions. Second, therapeutic strategies are addressed through macroscopic gels for localized treatment. These encompass natural polymer-based, synthetic polymer-based, and composite formulations. Applications include stent coatings, adventitial injections, and catheter-delivered depots. Natural polymers often possess intrinsic biological activities including anti-inflammatory and immunomodulatory properties that may contribute to therapeutic effects. Third, nano- and microgels for systemic delivery are examined. These include polymer-based nanogels with stimuli-responsive drug release responding to oxidative stress, pH changes, and enzymatic activity characteristic of atherosclerotic lesions. Inorganic–organic composite nanogels incorporating paramagnetic contrast agents enable theranostic applications by combining therapy with imaging-guided treatment monitoring. Current challenges include manufacturing consistency, mechanical stability under physiological flow, long-term safety assessment, and regulatory pathway definition. Future opportunities are discussed in multi-functional integration, artificial intelligence-guided design, personalized formulations, and biomimetic approaches. Gel technologies demonstrate substantial potential to advance atherosclerosis management through improved spatial and temporal control over therapeutic interventions.

Breast cancer treatment still faces challenges including local recurrence, systemic toxicity, tumor heterogeneity, drug resistance, and immunosuppression. Conventional systemic administration provides limited exposure at the tumor site and exhibits significant toxicity. Injectable hydrogels, combining the properties of minimally invasive administration, in situ gelation, local retention, and sustained release, have become a key platform for local precision drug delivery. Compared with nanomedicines or free drugs, hydrogels can both prolong drug retention time and achieve on-demand release through the modulation of crosslinking density, degradation rate, and responsive chemical bonds. This review is organized around the material logic of such systems. Injectable hydrogels are first classified into natural, synthetic, hybrid, supramolecular, nanocomposite, and self-healing systems, the in situ gelation chemistries available to each are compared, and network parameters such as crosslinking density, mesh size, swelling, porosity, modulus, and rheology are related to release kinetics and intratumoral retention. Current research is primarily advancing along two directions: one is the construction of pH-, enzyme-, redox/ROS-, hypoxia-, ATP-, glucose-or thermo-responsive hydrogels; the other is achieving active targeting by integrating functionalized hydrogels with targets such as CD44, folate receptor, integrins, EGFR, transferrin receptor, and HER2 or with biomimetic cell-membrane coatings. On this basis, hydrogels have been extended to cancer vaccines, immune checkpoint modulation, local delivery of CAR-T/CAR-NK, as well as combination therapies involving chemotherapy, photothermal therapy, photodynamic therapy, chemodynamic therapy, sonodynamic therapy, radiosensitization, gene therapy, and theranostics. The constraints imposed on hydrogel design by different payload classes, including small molecules, natural products, proteins and peptides, nucleic acids, antibodies, exosomes, and gene-editing machinery, are further examined, and imaging-integrated theranostic gels are discussed together with the emerging role of machine learning and digital fabrication in hydrogel optimization. Based on the biological foundations of breast cancer, this review summarizes advances in the material design, microenvironment-responsive release, targeting strategies, immunomodulation, and combination therapy of hydrogels, critically evaluates the limitations of each strategy, and aims to provide a reference for the design of mechanistically well-defined and translatable hydrogel delivery systems for breast cancer.