4T1 Tumor-bearing Research Articles

Engineering Lipusu with lysophosphatidylcholine for improved tumor cellular uptake and anticancer efficacy.

Liposomes have been developed as drug delivery carriers to enhance the antitumor efficiency of therapeutic agents. Lipusu® (Lip), a paclitaxel (PTX) liposome, has been widely used in the treatment of breast cancer. Compared with PTX, Lip could change the biodistribution and reduce the systemic toxicity. However, there was no positive effect on the entry of PTX into tumor cells, and thus the therapeutic effect was not significantly improved. Therefore, it is meaningful to engineer Lip for improving tumor cellular uptake efficiency. Here, lysophosphatidylcholine (LPC)-engineered Lip (LPC-Lip) was constructed via inserting single chain lipid tails into liposomal lipid bilayers, which was realized by simple incubation. Compared with Lip, the better cellular uptake of liposomes modified with LPC resulted in enhanced cytotoxic activity of LPC-Lip in 4T1 cells. Furthermore, stronger tumor growth inhibition was observed in LPC-Lip treated 4T1 tumor-bearing mice without significant side effects. In conclusion, by modulating the lipid composition of Lip, the antitumor efficacy can be improved, and LPC engineered Lip may serve as a promising formulation of PTX for future cancer therapy.

A study on setting standards for near-infrared fluorescence-image guided surgery (NIRFGS) time lapse monitoring based on preoperative liver function assessment.

BackgroundThis study aimed to explore the relationship between the fluorescence intensity of indocyanine green (ICG) in near-infrared fluorescence guided surgery (NIRFGS) and preoperative liver function indicators.MethodsA total of 12 4T1 tumor-bearing mice were used for model establishment. Intraperitoneal injection (i.p.) of 20% carbon tetrachloride (CCl4) corn oil solution (50 µL) was given to mice in the liver injury model group, 24 hours after injection, the model was established, while the control group received 0% CCl4 corn oil solution (50 µL) (n=6 for each group). Additionally, doses of 8 mg/kg and 1 mg/kg of free ICG were injected intravenously (i.v.) (n=3 in each group). Fluorescence was imaged in vivo using an NIR fluorescence imaging system at different time points (1, 2, 4, 8, 12, 24, 48, and 72 h) after injection.ResultsThe absolute fluorescence intensity of mice in the liver injury model group was stronger than that in the control group. Mice in the liver injury model group had the same clearance rate of ICG from the tumor as normal mice. However, the background clearance rate was slower than that of normal mice, which prolonged the optimal tumor to background ratio (TBR) time. Correlation analysis was also used to determine which preoperative liver function parameters were most correlated with hepatic ICG clearance.ConclusionsLiver injury does not significantly affect the maximum TBR, but prolongs the optimal TBR time, and at the same time, a wider and more stable surgical window will appear. This study showed that a prolonged surgical start time is feasible according to preoperative liver function testing using NIR fluorescence imaging technology.

Development of fluorescent- and radio-traceable T1307-polymeric micelles as biomedical agents for cancer diagnosis: biodistribution on 4T1 tumor-bearing mice

In recent years, nanocarriers have been studied as promising pharmaceutical tools for controlled drug-delivery, treatment-efficacy follow-up and disease imaging. Among them, X-shaped amphiphilic polymeric micelles (Tetronic®, poloxamines) display great potential due to their biocompatibility and non-toxic effects, among others. In the present work, polymeric micelles based on the T1307 copolymer were initially decorated with a 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-fluorophore in order to determinate its in vivo biodistribution on 4T1 tumor-bearing mice. However, unfavorable results with this probe led to two different strategies. On the one hand, the BODIPY-micelle-loaded, L-T1307-BODIPY, and on the other hand, the 99mTc-micelle-radiolabeled, L-T1307- 99m Tc, were analyzed separately in vivo. The results indicated that T1307 accumulates mainly in the stomach, the kidneys, the lungs and the tumor, reaching the maximum organ-accumulation 2 hours after intravenous injection. Additionally, and according to the results obtained for L-T1307- 99m Tc, the capture of the polymeric micelles in organs could be observed up to 24 hours after injection. The results obtained in this work were promising towards the development of new radiotracer agents for breast cancer based on X-shaped polymeric micelles.

Enhancing Intersystem Crossing by Intermolecular Dimer-Stacking of Cyanine as Photosensitizer for Cancer Therapy

Enhancing Intersystem Crossing by Intermolecular Dimer-Stacking of Cyanine as Photosensitizer for Cancer Therapy

SKI-G-801, an AXL kinase inhibitor, blocks metastasis through inducing anti-tumor immune responses and potentiates anti-PD-1 therapy in mouse cancer models.

ObjectivesAXL‐mediated activation of aberrant tyrosine kinase drives various oncogenic processes and facilitates an immunosuppressive microenvironment. We evaluated the anti‐tumor and anti‐metastatic activities of SKI‐G‐801, a small‐molecule inhibitor of AXL, alone and in combination with anti‐PD‐1 therapy.Methods In vitro pAXL inhibition by SKI‐G‐801 was performed in both human and mouse cancer cell lines. Immunocompetent mouse models of tumor were established to measure anti‐metastatic potential of SKI‐G‐801. Furthermore, SKI‐G‐801, anti‐PD‐1 or their combination was administered as an adjuvant or neoadjuvant in the 4T1 tumor model to assess their potential for clinical application.ResultsSKI‐G‐801 robustly inhibited pAXL expression in various cell lines. SKI‐G‐801 alone or in combination with anti‐PD‐1 potently inhibited metastasis in B16F10 melanoma, CT26 colon and 4T1 breast models. SKI‐G‐801 inhibited the growth of B16F10 and 4T1 tumor‐bearing mice but not immune‐deficient mice. An antibody depletion assay revealed that CD8+ T cells significantly contributed to SKI‐G‐801‐mediated survival. Anti‐PD‐1 and combination group were observed the increased CD8+Ki67+ and effector T cells and M1 macrophage and decreased M2 macrophage, and granulocytic myeloid‐derived suppressor cell (G‐MDSC) compared to the control group. The neoadjuvant combination of SKI‐G‐801 and anti‐PD‐1 therapy achieved superior survival benefits by inducing more profound T‐cell responses in the 4T1 syngeneic mouse model.ConclusionSKI‐G‐801 significantly suppressed tumor metastasis and growth by enhancing anti‐tumor immune responses. Our results suggest that SKI‐G‐801 has the potential to overcome anti‐PD‐1 therapy resistance and allow more patients to benefit from anti‐PD‐1 therapy.

Engineered Cell-Derived Vesicles Displaying Targeting Peptide and Functionalized with Nanocarriers for Therapeutic microRNA Delivery to Triple-Negative Breast Cancer in Mice.

Polymeric nanocarriers (PNCs) can be used to deliver therapeutic microRNAs (miRNAs) to solid cancers. However, the ability of these nanocarriers to specifically target tumors remains a challenge. Alternatively, extracellular vesicles (EVs) derived from tumor cells show homotypic affinity to parent cells, but loading sufficient amounts of miRNAs into EVs is difficult. Here, it is investigated whether uPAR-targeted delivery of nanococktails containing PNCs loaded with therapeutic antimiRNAs, and coated with uPA engineered extracellular vesicles (uPA-eEVs) can elicit synergistic antitumor responses. The uPA-eEVs coating on PNCs increases natural tumor targeting affinities, thereby enhancing the antitumor activity of antimiRNA nanococktails. The systemic administration of uPA-eEV-PNCs nanococktail shows a robust tumor tropism, which significantly enhances the combinational antitumor effects of antimiRNA-21 and antimiRNA-10b, and leads to significant tumor regression and extension of progression free survival for syngeneic 4T1 tumor-bearing mice. In addition, the uPA-eEV-PNCs-antimiRNAs nanococktail plus low dose doxorubicin results in a synergistic antitumor effect as evidenced by inhibition of tumor growth, reduction of lung metastases, and extension of survival of 4T1 tumor-bearing mice. The targeted combinational nanococktail strategy could be readily translated to the clinical setting by using autologous cancer cells that have flexibility for ex vivo expansion and genetic engineering.

Molecularly Engineered Aptamers Targeting Tumor Tissue and Cancer Cells for Efficient in Vivo Recognition and Enrichment

Molecularly Engineered Aptamers Targeting Tumor Tissue and Cancer Cells for Efficient in Vivo Recognition and Enrichment

Double hit strategy using pH-sensitive liposomes containing doxorubicin and pheophorbide-a for combination tumor therapy

For successful combination therapy using nanoparticles, stable loading and targeted delivery of different drugs are important. Herein, we prepared pH-sensitive liposomes with hydrophilic doxorubicin (Dox) in the core and hydrophobic pheophobide-a (Pba) in the lipid membrane (pH-lipo-Dox-Pba). The liposomes provided high drug accumulation in tumor tissue, with an enhanced permeability and retention (EPR) effect and enhanced binding to tumor cells by cyclic Arg-Gly-Asp peptide (cRGD). After cellular uptake, Dox was released in response to the endo-lysosomal acidic pH and moved into the nucleus, while Pba remained in the cytosol. Therefore, a double hit strategy composed of a simultaneous attack on nucleus and cytosol could be achieved by chemo- and photodynamic therapy. High tumor accumulation of pH-lipo-Dox-Pba was observed after intravenous injection into 4T1 tumor-bearing mice. Effective suppression of tumor growth in the same mouse model demonstrated a synergetic effect of combination therapy enabled by the double hit strategy using pH-lipo-Dox-Pba.

Folic Acid Decorated Zeolitic Imidazolate Framework (ZIF-8) Loaded with Baicalin as a Nano-Drug Delivery System for Breast Cancer Therapy.

BackgroundBaicalin (BAN) has attracted widespread attention due to its low-toxicity and efficient antitumor activity, but its poor water solubility and low bioavailability severely limit its clinical application. Development of a targeted drug delivery system is a good strategy to improve the antitumor activity of baicalin.MethodsWe prepared a BAN nano-drug delivery system PEG-FA@ZIF-8@BAN with a zeolite imidazole framework-8 (ZIF-8) as a carrier, which can achieve the response of folate receptor (FR). We characterized this system in terms of morphology, particle size, zeta-potential, infrared (IR), ultraviolet (UV), x-ray diffraction (XRD), and Brunel-Emmett-Teller (BET), and examined the in vitro cytotoxicity and cellular uptake properties of PEG-FA@ZIF-8@BAN using MCF-7 cells. Lastly, we established a 4T1 tumor-bearing mouse model and evaluated its in vivo anti-mammary cancer activity.ResultsThe PEG-FA@ZIF-8@BAN nano-delivery system had good dispersion with a BAN loading efficiency of 41.45 ± 1.43%, hydrated particle size of 176 ± 8.1 nm, Zeta-potential of −23.83 ± 1.1 mV, and slow and massive drug release in an acidic environment (pH 5.0), whereas release was 11.03% in a neutral environment (pH 7.4). In vitro studies showed that PEG-FA@ZIF-8@BAN could significantly enhance the killing effect of BAN on MCF-7 cells, and the folic acid-mediated targeting could lead to better uptake of nanoparticles by tumor cells and thus better killing of cancer cells. In vivo studies also showed that PEG-FA@ZIF-8@BAN significantly increased the inhibition of the proliferation of solid breast cancer tumors (p < 0.01 or p < 0.001).ConclusionThe PEG-FA@ZIF-8@BAN nano-drug delivery system significantly enhanced the anti-breast cancer effect of baicalin both in vivo and in vitro, providing a more promising drug delivery system for the clinical applications and tumor management.

Boron difluoride formazanate dye for high‐efficiency NIR‐II fluorescence imaging‐guided cancer photothermal therapy

The small molecular second near-infrared (NIR-II, 1000–1700 nm) dye-based nanotheranostics can concurrently combine deep-tissue photodiagnosis with in situ phototherapy, which occupies a vital position in the early detection and precise treatment of tumors. However, the development of small molecular NIR-II dyes is still challenging due to the limited electron acceptors and cumbersome synthetic routes. Herein, we report a novel molecular electron acceptor, boron difluoride formazanate (BDF). Based on BDF, a new small molecular NIR-II dye BDF1005 is designed and synthesized with strong NIR-I absorption at 768 nm and bright NIR-II peak emission at 1034 nm. In vitro and in vivo experiments demonstrate that BDF1005-based nanotheranostics can be applied for NIR-II fluorescence imaging-guided photothermal therapy of 4T1 tumor-bearing mice. Under 808 nm laser irradiation, tumor growth can be effectively inhibited. This work opens up a new road for the exploitation of NIR-II small molecular dyes for cancer phototheranostics.

Hyaluronic Acid Derived Hypoxia-Sensitive Nanocarrier for Tumor Targeted Drug Delivery.

Hyaluronic acid (HA) is conjugated with BHQ3 moiety with azo bonds to prepare hypoxia-responsive polymer conjugate. Because of the amphiphilic nature, the polymer conjugate self-assembles to HA-BHQ3 nanoparticles (NPs). The anticancer drug doxorubicin (DOX) is loaded into the NPs. In the physiological environment, DOX is released slowly. In contrast, under hypoxic conditions, the azo bond in BHQ3 is cleaved, thus significantly enhancing the DOX release rate. For instance, after 24 h, 25% of DOX is released under normal conditions, while 74% of DOX is released under hypoxic conditions. In vitro cytotoxicity demonstrates higher toxicity in the hypoxic conditions. DOX@HA-BHQ3 NPs exhibit greater toxicity levels against 4T1 cells in hypoxic conditions. The fluorescent microscope images confirm the oxygen-dependent intracellular DOX release from the NPs. The in vivo biodistribution results suggest the tumor targetability of HA-BHQ3 NPs in 4T1 tumor-bearing mice.

Stapled Liposomes Enhance Cross‐Priming of Radio‐Immunotherapy

The release of tumor-associated antigens (TAAs) and their cross-presentation in dendritic cells (DCs) are crucial for radio-immunotherapy. However, the irradiation resistance of tumor cells usually results in limited TAA generation and release. Importantly, TAAs internalized by DCs are easily degraded in lysosomes, resulting in unsatisfactory extent of TAA cross-presentation. Herein, an antigen-capturing stapled liposome (ACSL) with a robust structure and bioactive surface is developed. The ACSLs capture and transport TAAs from lysosomes to the cytoplasm in DCs, thereby enhancing TAA cross-presentation. l-arginine encapsulated in ACSLs induces robust T cell-dependent antitumor response and immune memory in 4T1 tumor-bearing mice after local irradiation, resulting in significant tumor suppression and an abscopal effect. Replacing l-arginine with radiosensitizers, photosensitizers, and photothermal agents may make ACSL a universal platform for the rapid development of various combinations of anticancer therapies.

Mitochondria-Targeting MoS2-Based Nanoagents for Enhanced NIR-II Photothermal-Chemodynamic Synergistic Oncotherapy.

The synergy of chemodynamic therapy (CDT) and photothermal therapy (PTT) can improve anticancer efficacy, while the limited diffusion distance and the short lifetime of •OH still greatly restrict the therapeutic efficacy of PTT-CDT. Herein, MoS2@PDA-Fe@PEG/TPP (MPFPT) nanosheets (NSs) with mitochondria-targeting ability were reported for enhanced PTT-CDT synergistic oncotherapy. MPFPT NSs were prepared by covalent modification of poly(ethylene glycol) (PEG) and triphenylphosphonium (TPP) on polydopamine (PDA)-Fe3+coated MoS2 NSs. Co-localization experiments showed that MPFPT NSs can efficiently target mitochondria via the direction of TPP. Moreover, MPFPT NSs have good photothermal performance in the second near-infrared (NIR-II) region and can greatly accelerate the Fenton reaction from H2O2 to generate more hydroxyl radicals (•OH). In vitro experimental results showed that MPFPT NSs have improved therapeutic efficacy to cancer cells than similar MoS2-based nanoagents without mitochondria-targeting units, which can be attributed to the short distance between mitochondria and MPFPT NSs and the efficient damage of mitochondria by in situ generated •OH. In the 4T1 tumor-bearing mice model, MPFPT NSs demonstrated significantly enhanced therapeutic efficacy by PTT-CDT, suggesting the superiority of the mitochondria-targeting strategy. This study reveals that mitochondria-targeting MPFPT NSs are promising nanoagents for oncotherapy.

Aptamer-assisted tumor localization of bacteria for enhanced biotherapy

Despite bacterial-mediated biotherapies have been widely explored for treating different types of cancer, their implementation has been restricted by low treatment efficacy, due largely to the absence of tumor-specific accumulation following administration. Here, the conjugation of aptamers to bacterial surface is described by a simple and cytocompatible amidation procedure, which can significantly promote the localization of bacteria in tumor site after systemic administration. The surface density of aptamers can be easily adjusted by varying feed ratio and the conjugation is able to increase the stability of anchored aptamers. Optimal bacteria conjugated with an average of 2.8 × 105 aptamers per cell present the highest specificity to tumor cells in vitro, separately generating near 2- and 4-times higher accumulation in tumor tissue at 12 and 60 hours compared to unmodified bacteria. In both 4T1 and H22 tumor-bearing mouse models, aptamer-conjugated attenuated Salmonella show enhanced antitumor efficacy, along with highly activated immune responses inside the tumor. This work demonstrates how bacterial behaviors can be tuned by surface conjugation and supports the potential of aptamer-conjugated bacteria for both targeted intratumoral localization and enhanced tumor biotherapy.

Doxorubicin nanomedicine based on ginsenoside Rg1 with alleviated cardiotoxicity and enhanced antitumor activity.

Aim: The authors aimed to develop Dox@Rg1 nanoparticles with decreased cardiotoxicity to expand their application in cancer. Materials & methods: Dox@Rg1 nanoparticles were developed by encapsulating doxorubicin (Dox) ina self-assembled Rg1. The antitumor effect of the nanoparticles was estimated using 4T1 tumor-bearing mice and the protective effect on the heart was investigated in vitro and in vivo. Results: Different from Dox, the Dox@Rg1 nanoparticles induced increased cytotoxicity to tumor cells, which was decreased in cardiomyocytes by the inhibition of apoptosis. The study in vivo revealed that the Dox@Rg1 nanoparticles presented a perfect tumor-targeting ability and improved antitumor effects. Conclusion: Dox@Rg1 nanoparticles could enhance the antitumor effects and decrease the cardiotoxicity of Dox.

Precise Regulation of Enzyme-Nanozyme Cascade Reaction Kinetics by Magnetic Actuation toward Efficient Tumor Therapy.

Spatiotemporal regulation of multi-enzyme catalysis with stimuli is crucial in nature to meet different metabolic requirements but presents a challenge in artificial cascade systems. Here, we report a strategy for precise and tunable modulation of enzyme-nanozyme cascade reaction kinetics by remote magnetic stimulation. As a proof of concept, glucose oxidase (GOx) was immobilized onto a ferrimagnetic vortex iron oxide nanoring (Fe3O4 NR) functionalized with poly(ethylene glycol) of different molecular weights to construct a series of Fe3O4 NR@GOx with nanometer linking distances. The activities of GOx and the Fe3O4 NR nanozyme in these systems were shown to be differentially stimulated by Fe3O4 NR-mediated local heat in response to an alternating magnetic field (AMF), leading to modulated cascade reaction kinetics in a distance-dependent manner. Compared to the free GOx and Fe3O4 NR mixture, Fe3O4 NR(D2)@GOx with an optimum linking distance of 1 nm exhibits a superior kinetic match between GOx and the Fe3O4 NR nanozyme and over a 400-fold higher cascade activity under AMF exposure. This enables remarkable intracellular reactive oxygen species production and significantly improved tumor inhibition of AMF-stimulated Fe3O4 NR(D2)@GOx in 4T1 tumor-bearing mice. The strategy reported here offers a straightforward new tool for fine-tuning multi-enzyme catalysis at the molecular level using magnetic stimuli and holds great promise for use in a variety of biotechnology and synthetic biology applications.

PH-sensitive doxorubicin-tocopherol succinate prodrug encapsulated in docosahexaenoic acid-based nanostructured lipid carriers: An effective strategy to improve pharmacokinetics and reduce toxic effects

Side effects often limit the use of doxorubicin (DOX) in cancer treatment. We have recently developed a nanostructured lipid carrier (NLC) formulation for synergistic chemotherapy, encapsulating DOX and the anticancer adjuvants docosahexaenoic acid (DHA) and α-tocopherol succinate (TS). Hydrophobic ion-pairing with TS allowed a high DOX entrapment in the nanocarrier. In this work, we investigated the pharmacokinetics of this formulation after intravenous administration in mice. The first data obtained led us to propose synthesizing covalent DOX-TS conjugates to increase DOX retention in the NLC. We successfully conjugated DOX to TS via an amide or hydrazone bond. In vitro studies in 4T1 tumor cells indicated low cytotoxicity of the amide derivative, while the hydrazone conjugate was effective in killing cancer cells. We encapsulated the hydrazone derivative in a DHA-based nanocarrier (DOX-hyd-TS/NLC), which had reduced particle size and high drug encapsulation efficiency. The pH-sensitive hydrazone bond allowed controlled DOX release from the NLC, with increased drug release at acidic conditions. In vivo studies revealed that DOX-hyd-TS/NLC had a better pharmacokinetic profile than free DOX and attenuated the short-term cardiotoxic effects caused by DOX, such as QT prolongation and impaired left ventricular systolic function. Moreover, this formulation showed excellent therapeutic performance by reducing tumor growth in 4T1 tumor-bearing mice and decreasing DOX-induced toxicity to the heart and liver, demonstrated by hematologic, biochemical, and histologic analyses. These results indicate that DOX-hyd-TS/NLC may be a promising nanocarrier for breast cancer treatment.

Branched-Chain Amino Acids Catabolism Pathway Regulation Plays a Critical Role in the Improvement of Leukopenia Induced by Cyclophosphamide in 4T1 Tumor-Bearing Mice Treated With Lvjiaobuxue Granule.

Background: Cyclophosphamide is a common tumor chemotherapy drug used to treat various cancers. However, the resulting immunosuppression leads to leukopenia, which is a serious limiting factor in clinical application. Therefore, the introduction of immunomodulators as adjuvant therapy may help to reduce the hematological side effects of cyclophosphamide. Lvjiaobuxue granule has been widely used in the clinical treatment of gynecological diseases such as anemia and irregular menstruation. Recently, it has been found to increase the function of white blood cells, but its mechanism of action is still unclear. We aimed to reveal the mechanisms of Lvjiaobuxue granule against acute leukopenia by an integrated strategy combining metabolomics with network pharmacology. Methods: Subcutaneously inoculated 4T1 breast cancer cells to prepare tumor-bearing mice, intraperitoneal injection of cyclophosphamide to establish a 4T1 tumor-bearing mice leukopenia animal model, using pharmacodynamic indicators, metabolomics, network pharmacology and molecular biology and other technical methods. To comprehensively and systematically elucidate the effect and mechanism of Lvjiaobuxue granule in improving cyclophosphamide-induced leukopenia in 4T1 tumor-bearing mice. Results: Lvjiaobuxue granule can improve the blood routine parameters and organ index levels of the leukopenia model of 4T1 tumor-bearing mice. Metabolomics studies revealed that 15 endogenous metabolites in the spleen of mice were considered as potential biomarkers of Lvjiaobuxue granule for their protective effect. Metabonomics and network pharmacology integrated analysis indicated that Lvjiaobuxue granule exerted the leukocyte elevation activity by inhibiting the branched-chain amino acids (BCAAs) degradation pathway and increasing the levels of valine, leucine and isoleucine. The results of molecular biology also showed that Lvjiaobuxue granule can significantly regulate the key enzymes in the catabolism of BCAAs, which further illustrates the importance of BCAAs in improving leukopenia. Conclusion: Lvjiaobuxue granule exerts obvious pharmacological effects on the leukopenia model of 4T1 tumor-bearing mice induced by cyclophosphamide, which could be mediated by regulating the branched-chain amino acid degradation pathway and the levels of valine, leucine and isoleucine.

A Versatile Calcium Phosphate Nanogenerator for Tumor Microenvironment-activated Cancer Synergistic Therapy.

Gas therapy is an emerging "green" cancer treatment strategy; however, its outcome often restricted by the complexity, diversity, and heterogeneity of tumor. Herein, a tumor targeting and tumor microenvironment-activated calcium phosphate nanotheranostic system (denoted as GCAH) is constructed for effective synergistic cancer starvation/gas therapy. GCAH is obtained by a facile biomineralization strategy using glucose oxidase (GOx) as a biotemplate, followed by loading of l-Arginine (L-Arg) and modification of hyaluronic acid (HA) to allow special selectivity for glycoprotien CD44 overexpressed cancer cells. This nanotheranostic system not only exhausts the glucose nutrients in tumor region by the GOx-triggered glucose oxidation, the generated H2 O2 can oxidize L-Arg into NO under acidic tumor microenvironment for enhanced gas therapy. As such, there are significant enhancement effects of starvation therapy and gas therapy through the cascade reactions of GOx and L-Arg, which yields a remarkable synergistic therapeutic effect for 4T1 tumor-bearing mice without discernible toxic side effects.

Piperine-Loaded Glycyrrhizic Acid- and PLGA-Based Nanoparticles Modified with Transferrin for Antitumor : Piperine-Loaded Glycyrrhizic Acid- and PLGA-Based Nanoparticles.

The purpose of this study was to enhance the antitumor effect of piperine by constructing the nanoparticles modified with transferrin (Tf-PIP-NPs) and evaluating their efficacy in vitro and in vivo. The Tf-PIP-NPs were prepared by the solvent evaporation method, and their properties were characterized. The effects of Tf-PIP-NPs on cytotoxicity, cell uptake, apoptosis, and mitochondrial membrane potential were evaluated in HepG2 cells, MDA-MB-231 cells, and 4T1 cells. In a 4T1 tumor-bearing mouse model, the antitumor efficacy of Tf-PIP-NPs was assessed in terms of tumor volumes, changes in body weight, HE staining, and immunohistochemical analysis. With a mean particle size of 112.2 ± 1.27nm, the zeta potential of (- 28.0 ± 1.6mV) Tf-PIP-NPs were rapidly internalized by tumor cells after 1h through the transferrin receptor (TfR)-mediated endocytosis pathway, significantly inducing cellular apoptosis and mitochondrial membrane potential loss. Although Tf-PIP-NPs had no significant difference with PIP-NPs in tumor volume inhibition due to the presence of tumor microenvironment, it could significantly upregulate the expression of related pro-apoptotic proteins and induce tumor necrosis. We used the self-assembly properties of glycyrrhizic acid (GL) and polymer-PLGA to encapsulate piperine and modified with the transferrin, which provided a promising approach to improve the antitumor efficacy for anticarcinogen.