pH-labile artificial natural killer cells for overcoming tumor drug resistance

Multifunctional injectable hydrogel with self-supplied H2S release and bacterial inhibition for the wound healing with enhanced macrophages polarization via interfering with PI3K/Akt pathway

Hydrogen sulfide (H2S) gas therapy is beneficial for accelerating wound healing and alleviating the inflammatory process, but is seriously hindered by insufficient delivery and unsustainable release in vivo. This study presents a multifunctional injectable hydrogel, OC@ε-PL-SATO, composed of oxidized hyaluronic acid and N-acetylcysteine (NAC) as an initiator, carboxymethyl chitosan and S-aroylthiooxime modified ε-Poly-(l-lysine) (ε-PL-SATO). ε-PL-SATO is a NAC-responsive H2S donor. OC@ε-PL-SATO hydrogel is designed for the desired wound healing process, with rapid gelation (<30 s) and a sustained H2S release. After mixing and gelling, H2S could be long-term released from the hydrogel and effectively drives macrophages toward M2 polarization, thereby ameliorating the inflammatory response. Revealed by transcriptome analysis, the underlying mechanism is that OC@ε-PL-SATO hydrogel releasing H2S inhibits LPS-mediated inflammatory responses in RAW264.7 cells by interfering with phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling and NF-κB activation. Furthermore, the OC@ε-PL-SATO hydrogel effectively eliminates the bacterial burden and alleviates the accompanying inflammation in a rat model of cutaneous wound infection. Importantly, the sustained generation of H2S gas significantly promotes angiogenesis and collagen deposition, ultimately accelerating the wound repair. In conclusion, this study provides a multifunctional injectable hydrogel with rapid gelatinization and continuous H2S release for accelerating the infected wound healing.

Artificial cells and biomimicry cells: A rising star in the fight against cancer

Biomimetic Artificial Cells (ACs) are engineered systems that mimic the properties and functions of natural cells, offering significant potential for biomedical applications. The performance and applicability of these synthetic constructs depend on the choice of materials and fabrication methods. Our review delves into the materials, fabrication techniques, and diverse applications of ACs, emphasizing their transformative impact on the field of cancer therapy as smart vehicles for drug delivery, immune system stimulation, cancer cell targeting to minimize off-target effects and maximizing therapeutic efficacy as well as in vitro models for cancer research. By providing a comprehensive overview, we aim to elucidate how these synthetic cells can move the field forward, offering innovative solutions to longstanding challenges in cancer treatment and opening new frontiers in less toxic treatment options.

Mitochondria-targeted and ROS-sensitive main-chain ruthenium polymer overcomes cancer drug resistance

The clinical efficacy of platinum-based chemotherapeutics, such as cisplatin, has been compromised by the prevalent emergence of drug resistance. This has propelled the search for alternative metal-based anti-tumor agents. Herein, we introduce PolyRu, a novel amphiphilic polymer containing a ruthenium complex and thioketal bonds in its main chain, for lung cancer treatment. PolyRu can self-assemble into nanoparticles (NP@PolyRu) in aqueous solutions and degrade within the reactive oxygen species-rich tumor microenvironment. The ruthenium complex in PolyRu specifically targets mitochondria and induces cancer cell apoptosis. The efficacy of NP@PolyRu was validated in a patient-derived xenograft model of human lung cancer, where NP@PolyRu significantly suppressed tumor progression with favorable biocompatibility，and showed excellent anti-tumor immune effect. NP@PolyRu emerges as a promising candidate for addressing cancer drug resistance, signifying a substantial leap forward in the realm of metal polymer-based cancer therapeutics.

Cell membrane derived biomimetic nanomedicine for precision delivery of traditional Chinese medicine in cancer therapy

The rapidly developing modern nanotechnology has brought new vitality to the application of traditional Chinese medicine (TCM), improving the pharmacokinetics and bioavailability of unmodified natural drugs. However, synthetic materials inevitably introduce incompatibilities. This has led to focusing on biomimetic drug delivery systems (DDS) based on biologically derived cell membranes. This "top-down" approach to nanomedicine preparation is simple and effective, as the inherited cell membranes and cell surface substances can mimic nature when delivering drugs back into the body, interacting similarly to the source cells at the biological interface. The concept of biologically derived TCM and biomimetic membranes aligns well with nature, the human body, and medicine, thereby enhancing the in vivo compatibility of TCM. This review focused on the recent progress using biomimetic membranes for TCM in cancer therapy, emphasizing the effective integration of biomimetic nanomedicine and TCM in applications such as cancer diagnosis, imaging, precision treatment, and immunotherapy. The review also provided potential suggestions on the challenges and prospects in this field.

Tumor-Targeted Magnetic Micelles for Magnetic Resonance Imaging, Drug Delivery, and Overcoming Multidrug Resistance

Nasopharyngeal carcinoma (NPC) is prevalent in Southern China. Unfortunately, current treatments encounter multidrug resistance (MDR). Overexpression of P-glycoprotein (P-gp), resulting in the efflux of chemotherapy drugs, is one of the significant mechanisms causing MDR. d-α-Tocopheryl poly(ethylene glycol) 1000 succinate (TPGS) has been demonstrated to effectively inhibit P-gp expression. The objectives of this study are to improve tumor MRI imaging, optimize docetaxel (DOC) administration, and target P-gp to overcome NPC resistance. Multifunctional micelles of TPGS (MM@DOC), loaded with magnetic nanoparticles, were synthesized for the targeted delivery of the first-line anticancer drug. MM@DOC exhibited greater toxicity and induced higher levels of apoptosis in DOC-resistant NPC cells (C666-1/DOC) compared to DOC. MM@DOC loaded with magnetic nanoparticles improved the quality of tumor MRI imaging. MM@DOC also demonstrated significant antitumor effects in nude mice with C666-1/DOC NPC. In conclusion, MM@DOC exhibited promising inhibitory effects on resistant tumors both in vitro and in vivo, optimized tumor MRI imaging, and showed great potential in drug delivery and overcoming resistance.

Melittin-incorporated nanomedicines for enhanced cancer immunotherapy

Immunotherapy is a rapidly developing and effective strategy for cancer therapy. Among various immunotherapy approaches, peptides have garnered significant attention due to their potent immunomodulatory effects. In particular, melittin emerged as a promising candidate to enhance cancer immunotherapy by inducing immunogenic cell death, promoting the maturation of antigen-presenting cells, activating T cells, enhancing the infiltration and cytotoxicity of effector lymphocytes, and modulating macrophage phenotypes for relieving immunosuppression. However, the clinical application of melittin is limited by poor targeting and systemic toxicity. To overcome these challenges, melittin has been incorporated into biomaterials and related nanotechnologies, resulting in extended circulation time in vivo, improved targeting, reduced adverse effects, and enhanced anti-cancer immunological action. This review provides an in-depth analysis of the immunomodulatory effects of melittin-incorporated nanomedicines and examines their development and challenges for clinical cancer immunotherapy.

Melittin and phospholipase A2: Promising anti-cancer candidates from bee venom

As the research on cancer-related treatment deepens, integrating traditional therapies with emerging interventions reveals new therapeutic possibilities. Melittin and phospholipase A2, the primary anti-cancer components of bee venom, are currently gaining increasing attention. This article reviews the various formulations of melittin in cancer therapy and its potential applications in clinical treatments. The reviewed formulations include melittin analogs, hydrogels, adenoviruses, fusion toxins, fusion peptides/proteins, conjugates, liposomes, and nanoparticles. The article also explored the collaborative therapeutic effects of melittin with natural products, synthetic drugs, radiotherapy, and gene expression regulatory strategies. Phospholipase A2 plays a key role in bee venom anti-cancer strategy due to its unique biological activity. Using an extensive literature review and the latest scientific results, this paper explores the current state and challenges of this field, with the aim to provide new perspectives that guide future research and potential clinical applications. This will further promote the application of bee venom in cancer therapy.

Polyphenol-Based Self-Assembled Nanomedicine for a Three-Pronged Approach to Reversing Tumor Immunosuppression

The challenges of multi-pathway immune resistance and systemic toxicity caused by the direct injection of immune checkpoint inhibitors are critical factors that compromise the effectiveness of clinical immune checkpoint blockade therapy. In this context, natural polyphenols have been employed as the primary component to construct a targeted and acid-responsive PD-L1 antibody (αPD-L1) delivery nanoplatform. This platform incorporates garcinol, an inhibitor of the Nuclear Factor Kappa-B (NF-κB) signaling pathway, to regulate pro-tumor immune escape cytokines and regulatory T cells. Additionally, the nanoplatform has been verified to induce immunogenic cell death (ICD), which promotes the maturation of dendritic cells and enhances the activity of cytotoxic T lymphocytes. In vivo and in vitro experimental results demonstrated that the nanoplatform can boost the immune response through a PD-L1 and NF-κB blocking/ICD inducing three-pronged strategy, thereby effectively combating tumor growth and metastasis.

Recent advances in the development of tumor microenvironment-activatable nanomotors for deep tumor penetration

Cancer represents a significant threat to human health, with the use of traditional chemotherapy drugs being limited by their harsh side effects. Tumor-targeted nanocarriers have emerged as a promising solution to this problem, as they can deliver drugs directly to the tumor site, improving drug effectiveness and reducing adverse effects. However, the efficacy of most nanomedicines is hindered by poor penetration into solid tumors. Nanomotors, capable of converting various forms of energy into mechanical energy for self-propelled movement, offer a potential solution for enhancing drug delivery to deep tumor regions. External force-driven nanomotors, such as those powered by magnetic fields or ultrasound, provide precise control but often necessitate bulky and costly external equipment. Bio-driven nanomotors, propelled by sperm, macrophages, or bacteria, utilize biological molecules for self-propulsion and are well-suited to the physiological environment. However, they are constrained by limited lifespan, inadequate speed, and potential immune responses. To address these issues, nanomotors have been engineered to propel themselves forward by catalyzing intrinsic "fuel" in the tumor microenvironment. This mechanism facilitates their penetration through biological barriers, allowing them to reach deep tumor regions for targeted drug delivery. In this regard, this article provides a review of tumor microenvironment-activatable nanomotors (fueled by hydrogen peroxide, urea, arginine), and discusses their prospects and challenges in clinical translation, aiming to offer new insights for safe, efficient, and precise treatment in cancer therapy.

Specific and efficient knockdown of intracellular miRNA using partially neutralized phosphate-methylated DNA oligonucleic acid-loaded mesoporous silica nanoparticles

Antisense oligonucleotides (ASOs) are molecules used to regulate RNA expression by targeting specific RNA sequences. One specific type of ASO, known as neutralized DNA (nDNA), contains site-specific methyl phosphotriester (MPTE) linkages on the phosphate backbone, changing the negatively charged DNA phosphodiester into a neutralized MPTE with designed locations. While nDNA has previously been employed as a sensitive nucleotide sequencing probe for the PCR, the potential of nDNA in intracellular RNA regulation and gene therapy remains underexplored. Our study aims to evaluate the regulatory capacity of nDNA as an ASO probe in cellular gene expression. We demonstrated that by tuning MPTE locations, partially and intermediately methylated nDNA loaded onto mesoporous silica nanoparticles (MSNs) can effectively knock down the intracellular miRNA, subsequently resulting in downstream mRNA regulation in colorectal cancer cell HCT116. Additionally, the nDNA ASO-loaded MSNs exhibit superior efficacy in reducing miR-21 levels over 72 hours compared to the efficacy of canonical DNA ASO-loaded MSNs. The reduction in the miR-21 level subsequently resulted in the enhanced mRNA levels of tumour-suppressing genes PTEN and PDCD4. Our findings underscore the potential of nDNA in gene therapies, especially in cancer treatment via a fine-tuned methylation location.

Immunomodulatory activities and biomedical applications of melittin and its recent advances

Melittin (MLT), a peptide containing 26 amino acids, is a key constituent of bee venom. It comprises ∼40%-60% of the venom's dry weight and is the main pricing index for bee venom, being the causative factor of pain. The unique properties of MLT extracted from bee venom have made it a very valuable active ingredient in the pharmaceutical industry as this cationic and amphipathic peptide has propitious effects on human health in diverse biological processes. It has the ability to strongly impact the membranes of cells and display hemolytic activity with anticancer characteristics. However, the clinical application of MLT has been limited by its severe hemolytic activity, which poses a challenge for therapeutic use. By employing more efficient mechanisms, such as modifying the MLT sequence, genetic engineering, and nano-delivery systems, it is anticipated that the limitations posed by MLT can be overcome, thereby enabling its wider application in therapeutic contexts. This review has outlined recent advancements in MLT's nano-delivery systems and genetically engineered cells expressing MLT and provided an overview of where the MLTMLT's platforms are and where they will go in the future with the challenges ahead. The focus is on exploring how these approaches can overcome the limitations associated with MLT's hemolytic activity and improve its selectivity and efficacy in targeting cancer cells. These advancements hold promise for the creation of innovative and enhanced therapeutic approaches based on MLT for the treatment of cancer.

Investigation of Anticancer Therapy Using pH-Sensitive Carbon Dots-Functionalized Doxorubicin in Cubosomes

Cancer remains a highly lethal disease due to its elusive early detection, rapid spread, and significant side effects. Nanomedicine has emerged as a promising platform for drug delivery, diagnosis, and treatment monitoring. In particular, carbon dots (CDs), a type of fluorescent nanomaterial, offer excellent fluorescence properties and the ability to carry multiple drugs simultaneously through covalent bonding. In this work, CDs with carbonyl groups on the surface were prepared by aldol condensation and reacted with amine groups in the structure of doxorubicin (DOX) through Schiff base reaction to generate pH-responsive CDs-DOX. On the other hand, cubosomes with three-dimensional lattice structures formed by lipid bilayers have advantageous capabilities of encapsulating various hydrophilic, amphiphilic, and hydrophobic substances. The pH-responsive CDs-DOX are subsequently loaded into cubosomes to form an anticancer therapeutic nanosystem, CDs-DOX@cubosome. Leveraging the unique properties of CDs-DOX and cubosomes, our CDs-DOX@cubosome can enter tumor tissue through the enhanced permeation and retention effect first and conduct membrane fusion with tumor cells to intracellularly release CDs-DOX. Then, the imine bond in CDs-DOX breaks under acidic conditions within human cancer cell lines (HeLa and HepG-2 cells), releasing DOX and achieving enhanced treatment of tumors. Additionally, fluorescent CDs can synchronously achieve real-time in situ diagnosis of tumor tissue. We demonstrate that our CDs-DOX@cubosome works as an excellent drug delivery system with therapeutic efficiency enhancement to the tumor and reduced side effects.

Exploring the potential of pH-sensitive polymers in targeted drug delivery

The pH-sensitive polymers have attained significant attention in the arena of targeted drug delivery (TDD) because of their exceptional capability to respond to alteration in pH in various physiological environments. This attribute aids pH-sensitive polymers to act as smart carriers for therapeutic agents, transporting them precisely to target locations while curtailing the release of drugs in off-targeted sites, thereby diminishing side effects. Many pH-responsive polymers in TDD have revealed promising results, with increased therapeutic efficacy and decreased toxic effects. Several pH-sensitive polymers, including, hydroxy-propyl-methyl cellulose, poly (methacrylic acid) (Eudragit series), poly (acrylic acid), and chitosan, have been broadly studied for their myriad applications in the management of various types of diseases. Additionally, the amalgamation of pH-sensitive polymers with, additive manufacturing techniques like 3D printing, has resulted in the progression of novel drug delivery systems that regulate drug release in a controlled manner. Herein, types of pH-sensitive polymers in TDD are systemically reviewed. We have briefly discussed the nanocarriers employed for the delivery of various pH-sensitive polymers in TDD. Finally, miscellaneous applications of pH-sensitive polymers are discussed thoroughly with special attention to the implication of 3D printing in pH-sensitive polymers.

Fully Active Delivery of Nanodrugs In Vivo via Remote Optical Manipulation

The active delivery of nanodrugs has been a bottleneck problem in nanomedicine. While modification of nanodrugs with targeting agents can enhance their retention at the lesion location, the transportation of nanodrugs in the circulation system is still a passive process. The navigation of nanodrugs with external forces such as magnetic field has been shown to be effective for active delivery, but the existing techniques are limited to specific materials like magnetic nanoparticles. In this study, an alternative actuation method is proposed based on optical manipulation for remote navigation of nanodrugs in vivo, which is compatible with most of the common drug carriers and exhibits significantly higher manipulation precision. By the programmable scanning of the laser beam, the motion trajectory and velocity of the nanodrugs can be precisely controlled in real time, making it possible for intelligent drug delivery, such as inverse-flow transportation, selective entry into specific vascular branch, and dynamic circumvention across obstacles. In addition, the controlled mass delivery of nanodrugs can be realized through indirect actuation by the microflow field. The developed optical manipulation method provides a new solution for the active delivery of nanodrugs, with promising potential for the treatment of blood diseases such as leukemia and thrombosis.

Reversal of Multidrug Resistance by the Synergistic Effect of Reversan and Hyperthermia to Potentiate the Chemotherapeutic Response of Doxorubicin in Glioblastoma and Glioblastoma Stem Cells

The glioblastoma stem cell (GSC) population in glioblastoma multiforme (GBM) poses major complication in clinical oncology owing to increased resistance to chemotherapeutic drugs, thereby limiting treatment in patients with recurring glioblastoma. To completely eradicate glioblastoma, a single therapy module is not enough; therefore, there is a need to develop a multimodal approach to eliminate bulk tumors along with the CSC population. With an aim to target transporters associated with multidrug resistance (MDR), such as P-glycoprotein (P-gp), a small-molecule inhibitor, reversan (RV) was used along with multifunctional magnetic nanoparticles (MNPs) for hyperthermia (HT) therapy and targeted drug delivery. Higher efflux of free doxorubicin (Dox) from the cells was stabilized by encapsulation in PPS-MnFe nanoparticles, whose physicochemical properties were determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Treatment with RV also enhanced the cellular uptake of PPS-MnFe-Dox, whereas RV and magnetic hyperthermia (MHT) together showed prolonged retention of fluorescence dye, Rhodamine123 (R123), in glioblastoma cells compared with individual treatment. Overall, in this work, we demonstrated the synergistic action of RV and HT to combat MDR in GBM and GSCs, and chemo-hyperthermia therapy enhanced the cytotoxic effect of the chemotherapeutic drug Dox (with lower effective concentration) and induced a higher degree of apoptosis compared to single-drug dosage.

pH-Responsive doxorubicin-loaded magnetosomes for magnetic resonance-guided focused ultrasound real-time monitoring and ablation of breast cancer

MR-guided focused ultrasound surgery (MRgFUS) is driving a new direction in non-invasive thermal ablation therapy with spatial specificity and real-time temperature monitoring. Although widely used in clinical practice, it remains challenging to completely ablate the tumor margin due to fear of damaging the surrounding tissues, thus leading to low efficacy and a series of complications. Herein, we have developed novel pH-responsive drug-loading magnetosomes (STPSD nanoplatform) for increasing the T2-contrast and improved the ablation efficiency with a clinical MRgFUS system. Specifically, this STPSD nanoplatform is functionalized by pH-responsive peptides (STP-TPE), encapsulating superparamagnetic iron oxide (SPIO) and doxorubicin (DOX), which can cause drug release and SPIO deposition at the tumor site triggered by acidity and MRgFUS. Under MRgFUS treatment, the increased vascular permeability caused by hyperthermia can improve the uptake of SPIO and DOX by tumor cells, so as to enhance ultrasound energy absorption and further enhance the efficacy of chemotherapy to completely ablate tumor margins. Moreover, we demonstrated that a series of MR sequences including T2-weighted imaging (T2WI), contrast-enhanced T1WI imaging (T1WI C+), maximum intensity projection (MIP), volume rendering (VR) and ADC mapping can be further utilized to monitor the MRgFUS ablation effect in rat models. Overall, this smart nanoplatform has the capacity to be a powerful tool to promote the therapeutic MRgFUS effect and minimize the side effects to surrounding tissues.

Nanosized Assemblies from Amphiphilic Solanesol Derivatives for Anticancer Drug Delivery

Unexpected functionalities of pharmaceutical excipients have been found in some cases. Preplanned introduction of excipients with therapeutic effects might not only reduce the risks of metabolism-related toxicity but also provide synergistic therapeutic effects. Herein, natural original solanesol (SOL), one of the isoprene compounds with some pharmacological activities, was selected to prepare a series of amphiphilic derivatives by chemical modification, and drug delivery systems for oncotherapy were established. Three derivatives, including solanesyl bromide (SOL-Br), monosolanesolsolanesyl succinate (MSS), and solanesylthiosalicylate (STS), were synthesized and formulated into nanosized self-assemblies for doxorubicin (DOX) encapsulation. Meanwhile, polyethylene glycol (PEG) derivatives were synthesized as the stabilizer of solanesol-based self-assemblies, among which hydrazine-poly(ethylene glycol)-hydrazine (PEG6000-DiHZ) was found to be more reliable. The optimized molar ratio between PEG6000-DiHZ and solanesol derivatives was found to be 2:1, considering the drug-loading capacity of self-assemblies. Consistent release profiles were found for the DOX-loaded self-assemblies, in which about 75-80% DOX was cumulatively released within 60 h at pH 5.0. The three DOX-loaded self-assemblies were found to be homogeneous spheres with average particle sizes in the range of 100-200 nm by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Blank self-assemblies were found to have an inhibiting ability toward MCF-7 and HepG-2 cancer cells, which might originate from the inherent nature of solanesol derivatives. In vivo pharmacodynamic experiments demonstrated that blank self-assemblies had certain inhibitory effect on tumor growth compared with the controls. Further enhanced effects were also found for the drug-loaded self-assemblies due to the synergistic anti-tumor effect existing between the drug and the carriers. This work has presented a simple and effective strategy to prepare a therapeutic carrier by direct assembling of the therapeutic compound without PEGylation steps, by which the therapeutic carrier materials could take their effect directly and synergistically along with the loaded drugs.

A novel natural killer-related signature to effectively predict prognosis in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a prevalent tumor that poses a significant threat to human health, with 80% of cases being primary HCC. At present, Early diagnosis and predict prognosis of HCC is challenging and the it is characterized by a high degree of invasiveness, both of which negatively impact patient prognosis. Natural killer cells (NK) play an important role in the development, diagnosis and prognosis of malignant tumors. The potential of NK cell-related genes for evaluating the prognosis of patients with hepatocellular carcinoma remains unexplored. This study aims to address this gap by investigating the association between NK cell-related genes and the prognosis of HCC patients, with the goal of developing a reliable model that can provide novel insights into evaluating the immunotherapy response and prognosis of these patients. This work has the potential to significantly advance our understanding of the complex interplay between immune cells and tumors, and may ultimately lead to improved clinical outcomes for HCC patients.

METHODS

For this study, we employed transcriptome expression data from the hepatocellular carcinoma cancer genome map (TCGA-LIHC) to develop a model consisting of NK cell-related genes. To construct the NK cell-related signature (NKRLSig), we utilized a combination of univariate COX regression, Area Under Curve (AUC) LASSO COX regression, and multivariate COX regression. To validate the model, we conducted external validation using the GSE14520 cohort.

RESULTS

We developed a prognostic model based on 5-NKRLSig (IL18RAP, CHP1, VAMP2, PIC3R1, PRKCD), which divided patients into high- and low-risk groups based on their risk score. The high-risk group was associated with a poor prognosis, and the risk score had good predictive ability across all clinical subgroups. The risk score and stage were found to be independent prognostic indicators for HCC patients when clinical factors were taken into account. We further created a nomogram incorporating the 5-NKRLSig and clinicopathological characteristics, which revealed that patients in the low-risk group had a better prognosis. Moreover, our analysis of immunotherapy and chemotherapy response indicated that patients in the low-risk group were more responsive to immunotherapy.

CONCLUSION

The model that we developed not only sheds light on the regulatory mechanism of NK cell-related genes in HCC, but also has the potential to advance our understanding of immunotherapy for HCC. With its strong predictive capacity, our model may prove useful in evaluating the prognosis of patients and guiding clinical decision-making for HCC patients.

Molecularly Stimuli-Responsive Self-Assembled Peptide Nanoparticles for Targeted Imaging and Therapy

Self-assembly has emerged as an extensively used method for constructing biomaterials with sizes ranging from nanometers to micrometers. Peptides have been extensively investigated for self-assembly. They are widely applied owing to their desirable biocompatibility, biodegradability, and tunable architecture. The development of peptide-based nanoparticles often requires complex synthetic processes involving chemical modification and supramolecular self-assembly. Stimuli-responsive peptide nanoparticles, also termed "smart" nanoparticles, capable of conformational and chemical changes in response to stimuli, have emerged as a class of promising materials. These smart nanoparticles find a diverse range of biomedical applications, including drug delivery, diagnostics, and biosensors. Stimuli-responsive systems include external stimuli (such as light, temperature, ultrasound, and magnetic fields) and internal stimuli (such as pH, redox environment, salt concentration, and biomarkers), facilitating the generation of a library of self-assembled biomaterials for biomedical imaging and therapy. Thus, in this review, we mainly focus on peptide-based nanoparticles built by self-assembly strategy and systematically discuss their mechanisms in response to various stimuli. Furthermore, we summarize the diverse range of biomedical applications of peptide-based nanomaterials, including diagnosis and therapy, to demonstrate their potential for medical translation.