Tumor Microenvironment-Responsive Nanoshuttles with Sodium Citrate Modification for Hierarchical Targeting and Improved Tumor Theranostics

FA-PEG Modified ZIF(Mn) Nanoparticles Loaded with Baicalin for Imaging-Guided Treatment of Melanoma in Mice

Background

Melanoma is an aggressive skin tumor with limited therapeutic options due to rapid proliferation, early metastasis, and poor prognosis. Baicalin (BA), a natural flavonoid, shows promise in inducing ferroptosis and apoptosis but faces challenges of poor solubility and bioavailability. To address these issues, we developed a multifunctional drug delivery system: manganese-doped ZIF-8 nanoparticles (ZIF(Mn)) loaded with BA and modified with folic acid (FA) and polyethylene glycol (PEG). FA targets melanoma cells by exploiting folate receptor overexpression, while PEG enhances biocompatibility and systemic circulation. Manganese enables magnetic resonance (MR) imaging for real-time, non-invasive therapy monitoring.

Methods

BA-loaded ZIF(Mn)/FA-PEG nanoparticles were synthesized via a one-pot method, enabling drug encapsulation, Mn²+ incorporation, and surface modification. The nanoparticles were comprehensively characterized (particle size, Zeta potential, FTIR, and XRD). Cytotoxicity and cellular uptake were evaluated in B16-F10 melanoma cells, and in vivo experiments in C57BL/6J mice investigated MR imaging capability, antitumor efficacy, and biosafety.

Results

BA@ZIF(Mn)/FA-PEG nanoparticles demonstrated excellent stability, a BA loading capacity of 33.50 ± 0.04%, and pH-responsive release, with accelerated drug release under acidic tumor conditions. Mn²+ provided strong T1-weighted MR imaging contrast. Cellular and animal studies showed enhanced uptake, reduced premature drug release, and improved compatibility. Mechanistically, the nanoparticles induced significant ferroptosis and apoptosis in melanoma cells, leading to potent antitumor effects.

Conclusion

The BA@ZIF(Mn)/FA-PEG nanoplatform effectively integrates targeted delivery, imaging guidance, and dual ferroptosis-apoptosis induction, offering a promising strategy for improving melanoma treatment outcomes.

A General "Two-Lock" Strategy to Enhance Drug Loading and Lysosomal Escape in Intelligent Boronate Ester Polymer Nanoparticles for Improved Chemotherapy

Boronate ester can be used to prepare intelligent polymer nanoparticles (NPs). However, the traditional boronate ester polymer NPs made of boronic acid and diols using a "single-lock" strategy (B-O NPs) exhibit low drug loading capacity (DLC) and insufficient lysosomal escape ability, resulting in limited antitumor efficacy. We develop a "two-lock" strategy that combines dodecanamine and boronic acid using boron-nitrogen (B ← N) coordination to enhance the formation of a boronate ester polymer. Through this strategy, amphiphilic dextran and poly(vinyl alcohol) are synthesized through conjugation with the phenylboronic acid (PBA)/dodecanamine complex. The amphiphilic dextran encapsulates paclitaxel (PTX) to form B-N-O NPs with a higher DLC than their "single-lock" compartments due to enhanced boronate ester stability and improved hydrophobic drug-polymer interactions. Moreover, the B-N-O NPs release more PTX under acidic conditions compared with the B-O NPs. To demonstrate the generality of this "two-lock" strategy, eight polymer prodrug B-N-O NPs employing poly(vinyl alcohol) or dextran, along with PBA-modified gemcitabine, fluorouracil, and 7-ethyl-10-hydroxycamptothecin, or boronic acid-containing bortezomib and dodecanamine, are prepared, showing overall enhanced DLC and higher responsive drug release efficiency compared to B-O NPs. Importantly, B-N-O NPs with a combination of dodecanamine and boronic acid show a better lysosomal escape capability than B-O NPs. Moreover, B-N-O NPs exhibit stronger cytotoxicity compared to B-O NPs and free drugs in vitro. Their enhanced drug loading, responsive drug release, and lysosomal escape abilities contribute to enhanced antitumor efficacy in vivo. This "two-lock" strategy can be a general and convenient method to prepare responsive polymer NPs with enhanced anticancer efficacy.

Fasting-Mimicking Diet Facilitates Anti-tumor Therapeutic Effects by Nutrient-Sensitive Nanocomposites

Cancer cells support their uncontrolled proliferation primarily by regulating energy metabolism. Inhibiting tumor growth by blocking the supply of nutrients is an effective treatment strategy. Fasting-mimicking diet (FMD), as a low-calorie, low-protein, low-sugar, high-fat diet, can effectively reduce the nutrient supply to tumor cells. However, the significant biological barrier presented by the tumor microenvironment imposes greater demands and challenges for drug design. This study constructs the multifunctional nanocomposite ZnFe2O4@TiO2@CHC@Orl-FA (ZTCOF), which has great potential to overcome the aforementioned drawbacks. ZnFe2O4@TiO2 could produce 1O2 with ultrasound, and stimulate the Fenton-like conversion of endogenous H2O2 to ·OH, achieving a combined therapeutic effect of sonodynamic therapy (SDT) and chemodynamic therapy (CDT). Orl (Orlistat) and CHC (α-cyano-4-hydroxycinnamic acid) not only block tumor cell energy metabolism but also increase sensitivity to reactive oxygen species, enhancing the cytotoxic effect on tumor cells. Furthermore, combining the treatment strategies with FMD condition control can further inhibit cancer cell energy metabolism, achieving significant synergistic anti-tumor therapy. Both in vitro and in vivo experiments confirm that ZTCOF with SDT/CDT/starvation can achieve effective tumor suppression and destruction. This work provides theoretical and technical support for anti-tumor multimodal synergistic therapy.

Cell membrane-coated biomimetic nanomedicines: productive cancer theranostic tools

As the second-leading cause of human death, cancer has drawn attention in the area of biomedical research and therapy from all around the world. Certainly, the development of nanotechnology has made it possible for nanoparticles (NPs) to be used as a carrier for delivery systems in the treatment of tumors. This is a biomimetic approach established to craft remedial strategies comprising NPs cloaked with membrane obtained from various natural cells like blood cells, bacterial cells, cancer cells, etc. Here we conduct an in-depth exploration of cell membrane-coated NPs (CMNPs) and their extensive array of applications including drug delivery, vaccination, phototherapy, immunotherapy, MRI imaging, PET imaging, multimodal imaging, gene therapy and a combination of photothermal and chemotherapy. This review article provides a thorough summary of the most recent developments in the use of CMNPs for the diagnosis and treatment of cancer. It critically assesses the state of research while recognizing significant accomplishments and innovations. Additionally, it indicates ongoing problems in clinical translation and associated queries that warrant deeper research. By doing so, this study encourages creative thinking for future projects in the field of tumor therapy using CMNPs while also educating academics on the present status of CMNP research.

Size transformable organic nanotheranostic agents for NIR-II imaging-guided oncotherapy

Nanotheranostic agents combined the second near-infrared (NIR-II, 1000-1700 nm) fluorescence imaging with phototherapy strategy have attracted tremendous interest. However, the actual efficacy of NIR-II probes could be weakened by their limited accumulation and penetration in tumor tissues. Herein, a size-transformable NIR-II nanotheranostic agent (BBT-HASS@FPMPL NPs) is employed for simultaneously enhanced penetration and retention in deep tumor tissue to realize precise image and effective PTT therapy. BBT-HASS@FPMPL NPs were first formed by using hyaluronic acid (HA) chains and disulfide bonds as stimuli-responsive "lock" to efficiently load conjugated oligomer (BBTN+), and then folic acid (FA) modified polylysine (FPMPL) shell was stacked at the surface by electrostatic interaction. Dual targeting with HA and FA is expected to lead to more selective targeting and better accumulation of BBT-HASS@FPMPL NPs in tumor sites. Simultaneously, obvious particle size reduction and charge reversal can be triggered in acidic tumor microenvironment to achieve deep intratumor filtration through transcytosis. Following tumor penetration, size change was further initiated by overexpressed hyaluronidase and GSH in tumor. Free BBTN+ can be subsequently released from nanoparticles to promote specific intratumor retention, which synergistically enhance photothermal therapeutic efficacy. Owing to sufficient tumor accumulation and deep penetration, the NIR-II emission of BBTN+ could further be used for precise monitoring of subcutaneous tumor progression in mice for 6 days with just one dose injection. We expect that such nanotheranostic platform that combined the high resolution of NIR-II fluorescence with deep tumor penetration and long intratumor retention could be useful for real-time monitoring of tumor process, precise diagnosis, and enhanced phototherapy.

Lipid-assisted PEG-b-PLA nanoparticles with ultrahigh SN38 loading capability for efficient cancer therapy

The topoisomerase I inhibitor, 7-ethyl-10-hydroxycamptothecin (SN38), has demonstrated potent anticancer activity. However, its clinical application is hindered by its low solubility and high crystallization propensity, which further complicates its encapsulation into nanoparticles for systemic delivery. Herein, we explore the utilization of lipid-assisted poly(ethylene glycol)-block-poly(D,L-lactide) (PEG-b-PLA) nanoparticles to achieve ultrahigh loading capability for SN38. Through the introduction of cationic, anionic, or neutral lipids, the SN38 loading efficiency and loading capacity is elevated to >90% and >10% respectively. These lipids efficiently attenuate the intermolecular π-π stacking of SN38, thereby disrupting its crystalline structure. Moreover, we assess the therapeutic activity of SN38-loaded formulations in various tumor models and identify an anionic lipid 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) sodium salt (DOPG)-assisted formulation that exhibits the highest anticancer activity and has favorable biosafety. Overall, our findings present a simple and robust strategy to achieve ultrahigh loading efficiency of SN38 using commonly employed PEG-b-PLA nanoparticles, opening up a new avenue for the systemic delivery of SN38.

Advances in Antitumor Nano-Drug Delivery Systems of 10-Hydroxycamptothecin

10-Hydroxycamptothecin (HCPT) is a natural plant alkaloid from Camptotheca that shows potent antitumor activity by targeting intracellular topoisomerase I. However, factors such as instability of the lactone ring and insolubility in water have limited the clinical application of this drug. In recent years, unprecedented advances in biomedical nanotechnology have facilitated the development of nano drug delivery systems. It has been found that nanomedicine can significantly improve the stability and water solubility of HCPT. NanoMedicines with different diagnostic and therapeutic functions have been developed to significantly improve the anticancer effect of HCPT. In this paper, we collected reports on HCPT nanomedicines against tumors in the past decade. Based on current research advances, we dissected the current status and limitations of HCPT nanomedicines development and looked forward to future research directions.

Dual-responsive nanoparticles with transformable shape and reversible charge for amplified chemo-photodynamic therapy of breast cancer

Herein, we designed a dual-response shape transformation and charge reversal strategy with chemo-photodynamic therapy to improve the blood circulation time, tumor penetration and retention, which finally enhanced the anti-tumor effect. In the system, hydrophobic photosensitizer chlorin e6 (Ce6), hydrophilic chemotherapeutic drug berberrubine (BBR) and matrix metalloproteinase-2 (MMP-2) response peptide (PLGVRKLVFF) were coupled by linkers to form a linear triblock molecule BBR-PLGVRKLVFF-Ce6 (BPC), which can self-assemble into nanoparticles. Then, positively charged BPC and polyethylene glycol-histidine (PEG-His) were mixed to form PEG-His@BPC with negative surface charge and long blood circulation time. Due to the acidic tumor microenvironment, the PEG shell was detached from PEG-His@BPC attributing to protonation of the histidine, which achieved charge reversal, size reduction and enhanced tumor penetration. At the same time, enzyme cutting site was exposed, and the spherical nanoparticles could transform into nanofibers following the enzymolysis by MMP-2, while BBR was released to kill tumors by inducing apoptosis. Compared with original nanoparticles, the nanofibers with photosensitizer Ce6 retained within tumor site for a longer time. Collectively, we provided a good example to fully use the intrinsic properties of different drugs and linkers to construct tumor microenvironment-responsive charge reversal and shape transformable nanoparticles with synergistic antitumor effect.

A Procedurally Activatable Nanoplatform for Chemo/Chemodynamic Synergistic Therapy

The responsive nano-drug delivery systems based on the complex characteristics of the tumor microenvironment (TME), such as acidic pH, hypoxia, and hydrogen peroxide (H2O2) overexpression, could enhance the biological activity...

Safety Evaluation of Nanotechnology Products

Nanomaterials are now being used in a wide variety of biomedical applications. Medical and health-related issues, however, have raised major concerns, in view of the potential risks of these materials against tissue, cells, and/or organs and these are still poorly understood. These particles are able to interact with the body in countless ways, and they can cause unexpected and hazardous toxicities, especially at cellular levels. Therefore, undertaking in vitro and in vivo experiments is vital to establish their toxicity with natural tissues. In this review, we discuss the underlying mechanisms of nanotoxicity and provide an overview on in vitro characterizations and cytotoxicity assays, as well as in vivo studies that emphasize blood circulation and the in vivo fate of nanomaterials. Our focus is on understanding the role that the physicochemical properties of nanomaterials play in determining their toxicity.

Construction of hollow polydopamine nanoparticle based drug sustainable release system and its application in bone regeneration

Nanomaterial-based drug sustainable release systems have been tentatively applied to bone regeneration. They, however, still face disadvantages of high toxicity, low biocompatibility, and low drug-load capacity. In view of the low toxicity and high biocompatibility of polymer nanomaterials and the excellent load capacity of hollow nanomaterials with high specific surface area, we evaluated the hollow polydopamine nanoparticles (HPDA NPs), in order to find an optimal system to effectively deliver the osteogenic drugs to improve treatment of bone defect. Data demonstrated that the HPDA NPs synthesized herein could efficiently load four types of osteogenic drugs and the drugs can effectively release from the HPDA NPs for a relatively longer time in vitro and in vivo with low toxicity and high biocompatibility. Results of qRT-PCR, ALP, and alizarin red S staining showed that drugs released from the HPDA NPs could promote osteogenic differentiation and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs) in vitro. Image data from micro-CT and H&E staining showed that all four osteogenic drugs released from the HPDA NPs effectively promoted bone regeneration in the defect of tooth extraction fossa in vivo, especially tacrolimus. These results suggest that the HPDA NPs, the biodegradable hollow polymer nanoparticles with high drug load rate and sustainable release ability, have good prospect to treat the bone defect in future clinical practice.

Tumor Microenvironment-Responsive Nanococktails for Synergistic Enhancement of Cancer Treatment via Cascade Reactions

A combination treatment strategy that relies on the synergetic effects of different therapeutic approaches has been considered to be an effective method for cancer therapy. Herein, a chemotherapeutic drug (doxorubicin, Dox) and a manganese ion (Mn²⁺) were co-loaded into regenerated silk fibroin-based nanoparticles (NPs), followed by the surface conjugation of phycocyanin (PC) to construct tumor microenvironment-activated nanococktails. The resultant PC-Mn@Dox-NPs showed increased drug release rates by responding to various stimulating factors (acidic pH, hydrogen peroxide (H₂O₂), and glutathione), revealing that they could efficiently release the payloads (Dox and Mn²⁺) in tumor cells. The released Dox could not only inhibit the growth of tumor cells but also generated a large amount of H₂O₂. The elevated H₂O₂ was decomposed into the highly harmful hydroxyl radicals and oxygen through an Mn²⁺-mediated Fenton-like reaction. Furthermore, the generated oxygen participated in photodynamic therapy (PDT) and produced abundant singlet oxygen. Our investigations demonstrate that these PC-Mn@Dox-NPs exhibit multiple bioresponsibilities and favorable biosafety. By integrating Dox-induced chemotherapy, Mn²⁺-mediated chemodynamic therapy, and PC-based PDT via cascade reactions, PC-Mn@Dox-NPs achieved enhanced in vitro and in vivo anticancer efficacies compared to all the mono- or dual-therapeutic approaches. These findings reveal that PC-Mn@Dox-NPs can be exploited as a promising nanococktail for cascade reaction-mediated synergistic cancer treatment.

pH-Sensitive Biomaterials for Drug Delivery

The development of precise and personalized medicine requires novel formulation strategies to deliver the therapeutic payloads to the pathological tissues, producing enhanced therapeutic outcome and reduced side effects. As many diseased tissues are feathered with acidic characteristics microenvironment, pH-sensitive biomaterials for drug delivery present great promise for the purpose, which could protect the therapeutic payloads from metabolism and degradation during in vivo circulation and exhibit responsive release of the therapeutics triggered by the acidic pathological tissues, especially for cancer treatment. In the past decades, many methodologies, such as acidic cleavage linkage, have been applied for fabrication of pH-responsive materials for both in vitro and in vivo applications. In this review, we will summarize some pH-sensitive drug delivery system for medical application, mainly focusing on the pH-sensitive linkage bonds and pH-sensitive biomaterials.

Multifunctional peptides for tumor therapy

Controlled nano-systems for drug delivery are designed to deliver therapeutical drugs to desirable sites on demand. Due to the diverse physiological functions of peptides, it is reasonable to introduce peptides into anti-tumor nano-system. The integration of peptides into nanomaterials has complementary advantages, which not only avoids the rapid degradation of peptides in vivo, but also improves the intelligence and functionality of the nano-system. We summarized the functional peptides with targeting and stimulus-responsive properties, and the present review outlined the most relevant and recent developed peptide-based multifunctional nanomaterials for tumor therapy.

BiVO4@Bi2S3 Heterojunction Nanorods with Enhanced Charge Separation Efficiency for Multimodal Imaging and Synergy Therapy of Tumor

Despite malignant tumors being one of the most serious diseases threatening human health and living quality, exploring theranostic agents for highly effective tumor diagnosis and treatment is still full of challenges. Herein, we demonstrate the design and preparation of Tween-20-modified BiVO₄@Bi₂S₃ heterojunction nanorods (HNRs) for multimodal computed tomography (CT)/photoacoustic (PA) imaging and radiotherapy (RT)/radiodynamic therapy (RDT)/photothermal therapy (PTT) synergistic therapy. Benefiting from the high X-ray attenuation coefficient of Bi, BiVO₄@Bi₂S₃ HNRs exhibit a sensitive CT imaging capacity and radiation enhancement effect during RT. Meanwhile, the strong NIR absorption of Bi₂S₃ endows BiVO₄@Bi₂S₃ HNRs with an excellent PA imaging and photothermal transformation capacity. More importantly, by taking advantage of the type II band alignment between BiVO₄ and Bi₂S₃, an extra internal electric field is established to accelerate the separation of X-ray-induced electrons and holes in BiVO₄@Bi₂S₃ HNRs, resulting in the realization of highly effective X-ray-induced RDT. Because the in vitro and in vivo experiments have verified that the RT/RDT/PTT synergistic therapeutic efficacy is greatly superior to any single treatment, it is believed that our BiVO₄@Bi₂S₃ HNRs can be used as the multifunctional nanotheranostic platform for malignant tumor theranostics.

Cell Membrane Coated-Biomimetic Nanoplatforms Toward Cancer Theranostics

Research of nanotechnology for cancer therapy and diagnosis extends beyond drug delivery into the targeted site or surveillance the distribution of nanodrugs in vivo or distinction tumor tissue from normal tissue. To satisfy the clinic needs, nanotheranostic platform should hide the surveillance by immune system and the sequestration by filtration organs (i.e., liver and spleen). Use of biologically derived cellular components in the fabrication of nanoparticles can hide these barriers. In this review, we update the recent progress on cell membrane-coated nanoparticles for cancer theranostics. We hope this review paper can inspire further innovations in biomimetic nanomedicine.

Nanomaterials for Nanotheranostics: Tuning Their Properties According to Disease Needs

Nanotheranostics is one of the biggest scientific breakthroughs in nanomedicine. Most of the currently available diagnosis and therapies are invasive, time-consuming, and associated with severe toxic side effects. Nanotheranostics, on the other hand, has the potential to bridge this gap by harnessing the capabilities of nanotechnology and nanomaterials for combined therapeutics and diagnostics with markedly enhanced efficacy. However, nanomaterial applications in nanotheranostics are still in its infancy. This is due to the fact that each disease has a particular microenvironment with well-defined characteristics, which promotes deeper selection criteria of nanomaterials to meet the disease needs. In this review, we have outlined how nanomaterials are designed and tailored for nanotheranostics of cancer and other diseases such as neurodegenerative, autoimmune (particularly on rheumatoid arthritis), and cardiovascular diseases. The penetrability and retention of a nanomaterial in the biological system, the therapeutic strategy used, and the imaging mode selected are some of the aspects discussed for each disease. The specific properties of the nanomaterials in terms of feasibility, physicochemical challenges, progress in clinical trials, its toxicity, and their future application on translational medicine are addressed. Our review meticulously and critically examines the applications of nanotheranostics with various nanomaterials, including graphene, across several diseases, offering a broader perspective of this emerging field.

Anchoring copper nanoclusters to Zn-containing hydroxy double salt: construction of 2D surface confinement induced enhanced emission toward bio-enzyme sensing and light-emitting diode fabrication

Surface CIEE based on Zn-HDS as host material and GSH-CuNCs as guest molecules was developed to produce fluorescence composite GSH-CuNCs/Zn-HDS for the first time.

Doxorubicin-loaded Cu2S/Tween-20 nanocomposites for light-triggered tumor photothermal therapy and chemotherapy

In clinical tumor therapy, traditional treatments such as surgery, radiotherapy and chemotherapy all have their own limitations. With the development of nanotechnology, new therapeutic methods based on nanomaterials such as photothermal therapy (PTT) have also emerged. PTT takes advantage of the poor thermal tolerance of tumor cells and uses the heat generated by photothermal reagents to kill tumor cells. A transition metal sulfide represented as Cu₂S is an ideal photothermal reagent because of its easy preparation, high extinction coefficient and photothermal conversion efficiency. Surface modification of nanoparticles (NPs) is also necessary, which not only can reduce toxicity and improve colloidal stability, but also can provide the possibility of further chemotherapeutic drug loading. In this work, we report the fabrication of Tween-20 (Tw20)-modified and doxorubicin (Dox)-loaded Cu₂S NPs (Cu₂S/Dox@Tw20 NPs), which significantly improves the performance in tumor therapy. Apart from the enhancement of colloidal stability and biocompatibility, the drug loading rate of Dox in Tw20 reaches 11.3%. Because of the loading of Dox, Cu₂S/Dox@Tw20 NPs exhibit chemotherapeutic behaviors and the tumor inhibition rate is 76.2%. Further combined with a near-infrared laser, the high temperature directly leads to the apoptosis of a large number of tumor cells, while the release of chemotherapeutic drugs under heat can not only continue to kill residual tumor cells, but also inhibit tumor recurrence. Therefore, with the combination of PTT and chemotherapy, the tumor was completely eliminated. Both hematological analysis and histopathological analysis proved that our experiments are safe.

In clinical tumor therapy, traditional treatments such as surgery, radiotherapy and chemotherapy all have their own limitations.

Targeted multifunctional nanomaterials with MRI, chemotherapy and photothermal therapy for the diagnosis and treatment of bladder cancer

Folate-modified vincristine-loaded polydopamine-coated Fe₃O₄ superparticles are designed as multifunctional nanomaterials for the imaging and treatment of bladder cancer.

Preparation of CdTe superparticles for white light-emitting diodes without Förster resonance energy transfer

Due to many unique and excellent optical properties, quantum dots (QDs) have been seen as one of the most promising color conversion materials in light-emitting diodes (LEDs). However, the Förster resonance energy transfer (FRET) among different colored QDs always causes a significant red-shift of the fluorescence emission, impeding the fabrication of LEDs with predicted photoluminescence (PL) emission spectra. In this work, we take advantage of CdTe superparticles (SPs), which are assembled by CdTe QDs, as the color conversion materials for the fabrication of WLEDs. Because of their submicron size, the distance between QDs with different emissions can be large enough to avoid the FRET process. More importantly, this method provides us with an opportunity to precisely design and regulate the PL emission spectra of LEDs. By easily overlapping the individual PL spectra of CdTe SPs with different emissions, the certain ratio of their usage for fabricating LEDs with desired PL emission spectra is identified. According to this idea, a WLED with a color rendering index (CRI) of 81, luminous efficacy of 27 lm W-1, and color coordinate at (0.33, 0.34) with the color temperature of 5742 K is achieved.

Multidrug resistant tumors-aimed theranostics on the basis of strong electrostatic attraction between resistant cells and nanomaterials

The gene expression of resistant cells usually raises the negative potential of cell membranes. Utilizing the strong electrostatic attraction of resistant cells with nanomaterials, multidrug resistance tumors-aimed theranostics is demonstrated.