Tumor Growth In Tumor-bearing Mice Research Articles

Therapeutic targeting of TNIK in papillary thyroid carcinoma: a novel approach for tumor growth suppression.

Papillary thyroid carcinoma (PTC) is a common endocrine malignancy. The pathology of PTC is far from clear. As a kinase that can be targeted, the role of TNIK in PTC has not been investigated. This study was focused on the effects and molecular mechanisms of TNIK in PTC. Both public datasets and clinical specimens were used to verify TNIK expression. The effects of TNIK were investigated in both cell lines and mice models. Transcriptome analysis was used to explore the underlying mechanism of TNIK. Immunofluorescence, wound healing, and qRT-PCR assays were used to validate the mechanism of TNIK in PTC. The therapeutic effects of TNIK inhibitor NCB-0846 were evaluated by flow cytometry, western blot, and subcutaneous xenografts mice. TNIK expression was upregulated in PTC tissues. TNIK knockdown could suppress cell proliferation and tumor growth in no matter cell models or nude mice. The transcriptome analysis, GO enrichment analysis, and GSEA analysis results indicated TNIK was highly correlated with cytoskeleton, cell motility, and Wnt pathways. The mechanistic studies demonstrated that TNIK regulated cytoskeleton remodeling and promoted cell migration. NCB-0846 significantly inhibited TNIK kinase activity, induced cell apoptosis, and activated apoptosis-related proteins in a dose-dependent manner. In addition, NCB-0846 inhibited tumor growth in tumor-bearing mice. In summary, we proposed a novel regulatory mechanism in which TNIK-mediated cytoskeleton remodeling and cell migration to regulate tumor progression in PTC. TNIK is a therapeutic target in PTC and NCB-0846 would act as a novel targeted drug for PTC therapy.

Cu–Tremella fuciformis polysaccharide–based tumor microenvironment–responsive injectable gels for cuproptosis-based synergistic osteosarcoma therapy

Cuproptosis affects osteosarcoma locally, and the exploitation of cuproptosis-related biomaterials for osteosarcoma treatment is still in its infancy. We designed and synthesized a novel injectable gel of Cu ion–coordinated Tremella fuciformis polysaccharide (TFP–Cu) for antiosteosarcoma therapy. This material has antitumor effects, the ability to stimulate immunity and promote bone formation, and a controlled Cu2+ release profile in smart response to tumor microenvironment stimulation. TFP–Cu can selectively inhibit the proliferation of K7M2 tumor cells by arresting the cell cycle and promoting cell apoptosis and cuproptosis. TFP–Cu also promoted the M1 polarization of RAW264.7 cells and regulated the immune microenvironment. These effects increased osteogenic gene and protein expression in MC3T3-E1 cells. TFP–Cu could significantly limit tumor growth in tumor-bearing mice by inducing tumor cell apoptosis and improving the activation of anti-CD8 T cell-mediated immune responses. Therefore, TFP–Cu could be a potential candidate for treating osteosarcoma and bioactive drug carrier for further cancer-related applications.

Targeted chemotherapy via HER2-based chimeric antigen receptor (CAR) engineered T-cell membrane coated polymeric nanoparticles

Cell membrane-derived nanoparticles (NPs) have recently gained popularity due to their desirable features in drug delivery such as mimicking properties of native cells, impeding systemic clearance, and altering foreign body responses. Besides NP technology, adoptive immunotherapy has emerged due to its promise in cancer specificity and therapeutic efficacy. In this research, we developed a biomimetic drug carrier based on chimeric antigen receptor (CAR) transduced T-cell membranes. For that purpose, anti-HER2 CAR-T cells were engineered via lentiviral transduction of anti-HER2 CAR coding lentiviral plasmids. Anti-HER2 CAR-T cells were characterized by their specific activities against the HER2 antigen and used for cell membrane extraction. Anti-cancer drug Cisplatin-loaded poly (D, l-lactide-co-glycolic acid) (PLGA) NPs were coated with anti-human epidermal growth factor receptor 2 (HER2)-specific CAR engineered T-cell membranes. Anti-HER2 CAR-T-cell membrane-coated PLGA NPs (CAR-T-MNPs) were characterized and confirmed via fluorescent microscopy and flow cytometry. Membrane-coated NPs showed a sustained drug release over the course of 21 days in physiological conditions. Cisplatin-loaded CAR-T-MNPs also inhibited the growth of multiple HER2+ cancer cells in vitro. In addition, in vitro uptake studies revealed that CAR-T-MNPs showed an increased uptake by A549 cells. These results were also confirmed via in vivo biodistribution and therapeutic studies using a subcutaneous lung cancer model in nude mice. CAR-T-MNPs localized preferentially at tumor areas compared to those of other studied groups and consisted of a significant reduction in tumor growth in tumor-bearing mice. In Conclusion, the new CAR modified cell membrane-coated NP drug-delivery platform has demonstrated its efficacy both in vitro and in vivo. Therefore, CAR engineered membrane-coated NP system could be a promising cell-mimicking drug carrier that could improve therapeutic outcomes of lung cancer treatments.

Liposomal co-delivery of toll-like receptors 3 and 7 agonists induce a hot triple-negative breast cancer immune environment

Triple-negative breast cancer (TNBC) is highly aggressive and has no standard treatment. Although being considered as an alternative to conventional treatments for TNBC, immunotherapy has to deal with many challenges that hinder its efficacy, particularly the poor immunogenic condition of the tumor microenvironment (TME). Herein, we designed a liposomal nanoparticle (LN) platform that delivers simultaneously toll-like receptor 7 (imiquimod, IQ) and toll-like receptor 3 (poly(I:C), IC) agonists to take advantage of the different toll-like receptor (TLR) signaling pathways, which enhances the condition of TME from a “cold” to a “hot” immunogenic state. The optimized IQ/IC-loaded LN (IQ/IC-LN) was effectively internalized by cancer cells, macrophages, and dendritic cells, followed by the release of the delivered drugs and subsequent stimulation of the TLR3 and TLR7 signaling pathways. This stimulation encouraged the secretion of type I interferon (IFN-α, IFN-β) and CXCLl0, a T-cell and antigen-presenting cells (APCs) recruitment chemokine, from both cancer cells and macrophages and polarized macrophages to the M1 subtype in in vitro studies. Notably, systemic administration of IQ/IC-LN allowed for the high accumulation of drug content in the tumor, followed by the effective uptake by immune cells in the TME. IQ/IC-LN treatment comprehensively enhanced the immunogenic condition in the TME, which robustly inhibited tumor growth in tumor-bearing mice. Furthermore, synergistic antitumor efficacy was obtained when the IQ/IC-LN-induced immunogenic state in TME was combined with anti-PD1 antibody therapy. Thus, our results suggest the potential of combining 2 TLR agonists to reform the TME from a “cold” to a “hot” state, supporting the therapeutic efficacy of immune checkpoint inhibitors.

Physalin A Induces Apoptosis and Autophagy in Hepatocellular Carcinoma via Inhibition of PI3K/Akt Signaling Pathway.

Physalin A (PA) is a bioactive withanolide with multiple pharmacological properties and has been indicated to be cytotoxic to hepatocellular carcinoma (HCC) cell line HepG2. This study aims to explore the mechanisms underlying PA antitumor activity in HCC. HepG2 cells were exposed to various concentrations of PA. Cell counting kit-8 assay and flow cytometry were implemented for evaluating cell viability and apoptosis, respectively. Immunofluorescence staining was utilized for detecting autophagic protein LC3. Western blotting was employed for measuring levels of autophagy-, apoptosis- and phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) signaling-related proteins. A xenograft mouse model was established to verify the antitumor activity of PA in vivo. PA impaired HepG2 cell viability, and triggered apoptosis as well as autophagy. Inhibiting autophagy augmented PA-evoked HepG2 cell apoptosis. PA repressed PI3K/Akt signaling in HCC cells and activating PI3K/Akt reversed PA-triggered apoptosis and autophagy. PA treatment inhibited tumor growth in tumor-bearing mice. PA triggers HCC cell apoptosis and autophagy by inactivating PI3K/Akt signaling.

ATB0,+-targeted nanoparticles initiate autophagy suppression to overcome chemoresistance for enhanced colorectal cancer therapy

Oxaliplatin (OXA) resistance remains the major obstacle to the successful chemotherapy of colorectal cancer (CRC). As a self-protection mechanism, autophagy may contribute to tumor drug resistance, therefore autophagy suppression could be regarded as a possible treatment option in chemotherapy. Cancer cells, especially drug-resistant tumor cells, increase their demand for specific amino acids by expanding exogenous supply and up-regulating de novo synthesis, to meet the needs for excessive proliferation. Therefore, it is possible to inhibit cancer cell proliferation through pharmacologically blocking the entry of amino acid into cancer cells. SLC6A14 (ATB0,+) is an essential amino acid transporter, that is often abnormally up-regulated in most cancer cells. Herein, in this study, we designed oxaliplatin/berbamine-coloaded, ATB0,+-targeted nanoparticles ((O + B)@Trp-NPs) to therapeutically target SLC6A14 (ATB0,+) and inhibit cancer proliferation. The (O + B)@Trp-NPs utilize the surface-modified tryptophan to achieve SLC6A14-targeted delivery of Berbamine (BBM), a compound that is found in a number of plants used in traditional Chinese medicine, which could suppress autolysosome formation though impairing autophagosome-lysosome fusion. We verified the feasibility of this strategy to overcome the OXA resistance during colorectal cancer treatment. The (O + B)@Trp-NPs significantly inhibited the proliferation and decreased the drug resistance of resistant colorectal cancer cells. In vivo, (O + B)@Trp-NPs greatly suppressed the tumor growth in tumor-bearing mice, which is consistent with the in vitro data. This research offers a unique and promising chemotherapeutic treatment for colorectal cancer.

Reversal of Cisplatin Resistance in Ovarian Cancer by the Multitargeted Nanodrug Delivery System Tf-Mn-MOF@Nira@CDDP.

Cisplatin (CDDP) is a widely used chemotherapeutic drug with proven efficacy for treating tumors. However, its use has been associated with severe side effects and eventually leads to drug resistance, thus limiting its clinical application in patients with ovarian cancer (OC). Herein, we aimed to investigate the success rate of reversing cisplatin resistance using a synthetic, multitargeted nanodrug delivery system comprising a Mn-based metal-organic framework (Mn-MOF) containing niraparib (Nira) and CDDP alongside transferrin (Tf) conjugated to the surface (Tf-Mn-MOF@Nira@CDDP; MNCT). Our results revealed that MNCT can target the tumor site, consume glutathione (GSH), which is highly expressed in drug-resistant cells, and then decompose to release the encapsulated Nira and CDDP. Nira and CDDP play a synergistic role in increasing DNA damage and apoptosis, exhibiting excellent antiproliferation, migration, and invasion activities. In addition, MNCT significantly inhibited tumor growth in tumor-bearing mice and exhibited excellent biocompatibility without side effects. Furthermore, it depleted GSH, downregulated multidrug-resistant transporter protein (MDR) expression, and upregulated tumor suppressor protein phosphatase and tensin homolog (PTEN) expression, consequently reducing DNA damage repair and reversing cisplatin resistance. These results indicate that multitargeted nanodrug delivery systems can provide a promising clinical approach to overcoming cisplatin resistance. This study provides an experimental basis for further investigation into multitargeted nanodrug delivery systems to reverse cisplatin resistance in patients with OC.

Construction of pH-Sensitive Nanovaccines Encapsulating Tumor Cell Lysates and Immune Adjuvants for Breast Cancer Therapy.

The current immunotherapy strategies for triple negative breast cancer (TNBC) are greatly limited due to the immunosuppressive tumor microenvironment (TME). Immunization with cancer vaccines composed of tumor cell lysates (TCL) can induce an effective antitumor immune response. However, this approach also has the disadvantages of inefficient antigen delivery to the tumor tissues and the limited immune response elicited by single-antigen vaccines. To overcome these limitations, a pH-sensitive nanocalcium carbonate (CaCO3 ) carrier loaded with TCL and immune adjuvant CpG (CpG oligodeoxynucleotide 1826) is herein constructed for TNBC immunotherapy. This tailor-made nanovaccine, termed CaCO3 @TCL/CpG, not only neutralizes the acidic TME through the consumption of lactate by CaCO3 , which increases the proportion of the M1/M2 macrophages and promotes infiltration of effector immune cells but also activates the dendritic cells in the tumor tissues and recruits cytotoxic T cells to further kill the tumor cells. In vivo fluorescence imaging study shows that the pegylated nanovaccine could stay longer in the blood circulation and extravasate preferentially into tumor site. Besides, the nanovaccine exhibits high cytotoxicity in 4T1 cells and significantly inhibits tumor growth of tumor-bearing mice. Overall, this pH-sensitive nanovaccine is a promising nanoplatform for enhanced immunotherapy of TNBC.

Delivery of quercetin for breast cancer and targeting potentiation via hyaluronic nano-micelles

Quercetin (QT) is a very effective anticancer drug in combating breast cancer. However, it has several disadvantages such as poor water solubility, low bioavailability and low targeting, which seriously restrict its clinical application. In this work, amphiphilic hyaluronic acid polymers (dHAD) were synthesized by grafting dodecylamine to hyaluronic acid (HA). The dHAD self-assembles with QT to form drug-carrying micelles (dHAD-QT). The dHAD-QT micelles possessed excellent drug-loading capacities (75.9 %) for QT and showed significantly improved CD44 targeting compared with unmodified HA. dHAD-QT micelles exhibited high cytotoxicity and apoptosis-inducing abilities, which were ascribed to the pH-sensitive dHAD-QT micelles accomplishing rapid drug release of QT under low pH condition. Importantly, in vivo experiments showed that dHAD-QT effectively inhibited tumor growth in tumor-bearing mice, with a tumor inhibition rate of 91.8 %. Furthermore, dHAD-QT prolonged the survival time of tumor-bearing mice and reduced the toxicity of the drug to normal tissues. These findings indicate that the designed dHAD-QT micelles have promising potential as efficient nano-drugs for breast cancer treatment.

Zhao’s Weitiao No 3 inhibits tumor growth in gastric cancer-bearing nude mice

Purpose: To investigate the effect of Zhao’s Weitiao No. 3 (ZW3) on the progression of gastric cancer (GC) in mice, and to determine its effects on the proliferation and apoptosis of gastric cancer tissues.
 Methods: Tumor growth in vivo was used to determine the effect of ZW3 (15, 30, and 60 mg/kg) on GC growth in mice. Immunohistochemical and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assays were conducted to evaluate the effects of ZW3 on the proliferation and apoptosis of mouse GC tissues, while quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunoblot assays were conducted to determine its effects on GC cell apoptosis.
 Results: ZW3 inhibited tumor growth in tumor-bearing mice, suppressed the expression of proliferation-related proteins (p < 0.001), increased the apoptosis of tumor cells in tumor-bearing mice (p < 0.001), and suppressed the expression of apoptosis-related proteins in mouse tumor tissues (p < 0.001).
 Conclusion: Thus, ZW3 is a potential drug for the management of GC. However, further investigations are required to determine its full potential

Antigen-Loaded Extracellular Vesicles Induce Responsiveness to Anti-PD-1 and Anti-PD-L1 Treatment in a Checkpoint Refractory Melanoma Model.

Extracellular vesicles (EV) are important mediators of intercellular communication and are potential candidates for cancer immunotherapy. Immune checkpoint blockade, specifically targeting the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) axis, mitigates T-cell exhaustion, but is only effective in a subset of patients with cancer. Reasons for therapy resistance include low primary T-cell activation to cancer antigens, poor antigen presentation, and reduced T-cell infiltration into the tumor. Therefore, combination strategies have been extensively explored. Here, we investigated whether EV therapy could induce susceptibility to anti-PD-1 or anti-PD-L1 therapy in a checkpoint-refractory B16 melanoma model. Injection of dendritic cell-derived EVs, but not checkpoint blockade, induced a potent antigen-specific T-cell response and reduced tumor growth in tumor-bearing mice. Combination therapy of EVs and anti-PD-1 or anti-PD-L1 potentiated immune responses to ovalbumin- and α-galactosylceramide-loaded EVs in the therapeutic model. Moreover, combination therapy resulted in increased survival in a prophylactic tumor model. This demonstrates that EVs can induce potent antitumor immune responses in checkpoint refractory cancer and induce anti-PD-1 or anti-PD-L1 responses in a previously nonresponsive tumor model.

Patchouli alcohol inhibits GPBAR1-mediated cell proliferation, apoptosis, migration, and invasion in prostate cancer.

G protein-coupled bile acid receptor 1 (GPBAR1) is a G protein-coupled receptor for bile acids, which is widely expressed in many human tissues. Patchouli alcohol (PA) has been shown to have an anti-cancer effect, including in prostate cancer (PCa). This study sought to confirm the regulatory mechanism of GPBAR1 in the anti-cancer activity of PA in PCa. The SwissTargetPrediction website (Pro >0) was used to predict the target of PA. The UALCAN and The Cancer Genome Atlas-Prostate cohort was used to examine the differentially expressed genes and PCa recurrence. A gene set enrichment analysis (GSEA) was conducted to analyze the relationship between the expression of GPBAR1 and PCa proliferation, migration, and invasion. Cell proliferation, migration, and invasion were assessed by colony formation, 5-Ethynyl-2'-deoxyuridine staining, cellscratch assays, and Transwell invasion assays, respectively. A xenograft animal model was established to assess the effect of PA on tumor growth in vivo. GPBAR1 protein and apoptosis related protein expression was measured by western blot. GPBAR1 was a PA target predicted by the SwissTargetPrediction website. PA inhibited the expression of GPBAR1 in PCa cells in a time- and dose-dependent manner. The abnormal expression of GPBAR1 was related to cell proliferation, migration, and invasion. Additionally, GPBAR1 overexpression promoted the cell proliferation, migration, and invasion, and inhibited the apoptosis of PCa cells. GPBAR1 silencing inhibited the cell proliferation, migration, and invasion, and promoted the apoptosis of PCa cells. High expressions of GPBAR1 suppressed tumor growth in tumor-bearing mice. Further, GPBAR1 promoted the activation of nuclear factor kappa B (NF-κB) signaling, and PA regulated the malignant phenotypes of PCa cells via the NF-κB signaling pathway mediated by GPBAR1. GPBAR1 is a promising drug target of PA, and was shown to regulate the proliferation, apoptosis, migration, and invasion of PCa cells through GPBAR1/NF-κB inhibition.

Facile preparation of a novel hyaluronic acid-modified metal-polyphenol photothermal nanoformulation for tumor therapy

Photothermal therapy (PTT) is a potentially effective and non-invasive tumor therapy that has attracted the attention of many researchers. This study systematically investigated the formation of metal-polyphenol nanoparticles and their photothermal properties. A simple physical self-assembly method was used to embed hyaluronic acid (HA) into metal-polyphenol nanoparticles, and a novel type of HA-modified ferrous baicalein nanoparticle (HFBNP) was successfully prepared for the first time. Unlike most current methods that utilize positive and negative charge attraction or chemical bonding, the method proposed in this study is to embed HA into nanostructures to reduce the risk of HA shedding in the circulation, thereby improving the tumor targeting efficiency while avoiding the use of other chemical reagents. HFBNP had a suitable size distribution and good biosafety meanwhile efficiently converting near-infrared (NIR) laser energy into thermal energy. The active targeting capability mediated by HA significantly increased the uptake of nanoparticles by tumor cells, and HFBNP exhibited a strong growth inhibitory effect on tumor cells under NIR laser irradiation. With the combination of PTT and chemotherapy, HFBNP significantly inhibited tumor growth in tumor-bearing mice. In conclusion, the nanosystem prepared in this study provides a new strategy for tumor therapy.

Alkaline plasma-activated water (PAW) as an innovative therapeutic avenue for cancer treatment

Plasma-activated water (PAW) is considered to be an effective anticancer agent due to the diverse aqueous reactive oxygen and nitrogen species (RONS: ROS and RNS), but the drawback of low dose and short duration of RONS in acidified PAW limits their clinical application. Herein, this Letter presents an innovative therapeutic avenue for cancer treatment with highly-effective alkaline PAW prepared by air surface plasma. This anticancer alkaline formulation is comprised of a rich mixture of highly chemical RONS and exhibited a prolonged half-life compared to acidified PAW. The H2O2, NO2−, and ONOO−/O2− concentrations in the alkaline PAW can reach up to 18-, 16-, and 14-fold higher than that in acidic PAW, and the half-life of these species was extended over 8-, 10-, and 26-fold, respectively. The synergistic potent redox action between these RONS with alkaline pH was shown to be more potent than acidic PAW for cancer cell inhibition in vitro. Furthermore, the alkaline PAW injection treatment also significantly inhibited tumor growth in tumor-bearing mice. The possible reasons are that the alkaline PAW would disturb the acid extracellular milieu leading to the inhibition of tumor growth and progression; moreover, the efficient and durable RONS with alkaline pH could induce significant cell apoptosis by altering cell biomolecules and participating apoptosis-related signaling pathways. These findings offer promising applications for developing a strategy with real potential for tumor treatment in clinical applications.

PH-responsive and targeted delivery of rutin for breast cancer therapy via folic acid-functionalized carbon dots

Here, first we have synthesized carbon dots (CDs) from red Korean ginseng, and modified further with folic acid (FA) for the targeted and controlled delivery of a natual flavonoid, rutin (RUT). FA conjugated and morin loaded CDs (FA-CDs-RUT) displayed size ~70 nm, drug loading content of 14.5 % and a pH-dependent drug release behaviour. Human breast cancer MCF-7 cells were taken for checking the anticancer activities of FA-CDs-RUT. The nanohybrids (FA-CDs-RUT) showed a dose-dependent (10–50 μg/mL) cytotoxicity in MCF-7 cells and caused apoptotic cell death by inducing oxidative stress and mitochondrial damage. Besides, anti-migratory role of FA-CDs-RUT was also observed. The in vivo intravenous (i.v.) administration of FA-CDs-RUT nanohybrid was found to effectively decrease the tumor growth in tumor-bearing mice as compared with bare rutin and CDs. Interestingly, none of the nanoformulations and bare rutin caused any significant alterations in blood biochemical parameters. The enhanced anticancer activity of FA-CDs-RUT is thought to be due to combinatorial anticancer effects of CDs and rutin. We also performed docking study of rutin with Bcl-2 to gain insights into possible pathways of cell growth regulation. Molecular docking study shown that rutin binds with Bcl-2 with binding affinity of −7.6 k Cal/mol. Together, this study provides insight into the usability of FA-CDs-RUT to treat breast cancer with their mechanisms of action.

Elucidation of the Mechanism of Topotecan-induced Antitumor Immune Activation

Danger-associated molecular patterns (DAMPs) derived from damaged or dying cells elicit inflammation and potentiate antitumor immune responses. We found that treatment of cancer cells with the antitumor agent topotecan (TPT), an inhibitor of topoisomerase I (TOP1), induces DAMP secretion that triggers dendritic cell activation and cytokine production. TPT administration inhibits tumor growth in tumor-bearing mice, which is accompanied by infiltration of activated DCs and CD8+ T cells. These effects are abrogated in mice lacking stimulator of interferon genes (STING), an essential molecule in cytosolic DNA-mediated innate immune responses. Furthermore, we identified ribosomal protein L15 (RPL15), a 60S ribosomal protein, as a novel TPT target and showed that TPT inhibited pre-ribosomal subunit formation via its binding to RPL15, resulting in the induction of DAMP-mediated antitumor immune activation independent of TOP1. RPL15 knockdown induced DAMP secretion and increased the cytotoxic T lymphocyte (CTL) population but decreased the T-regulatory cell (Treg) population in a B16-F10 murine melanoma model, which sensitized B16-F10 tumors against programmed death receptor-1(PD-1) blockade. Our study identified a novel TPT target protein and showed that ribosomal stress is a trigger of DAMP secretion, which contributes to antitumor immunotherapy.

Multifunctional Nanosnowflakes for T1-T2 Double-Contrast Enhanced MRI and PAI Guided Oxygen Self-Supplementing Effective Anti-Tumor Therapy.

IntroductionAccurate tumor diagnosis is essential to achieve the ideal therapeutic effect. However, it is difficult to accurately diagnose cancer using a single imaging method because of the technical limitations. Multimodal imaging plays an increasingly important role in tumor treatment. Photodynamic therapy (PDT) has received widespread attention in tumor treatment due to its high specificity and controllable photocytotoxicity. Nevertheless, PDT is susceptible to tumor microenvironment (TME) hypoxia, which greatly reduces the therapeutic effect of tumor treatment.MethodsIn this study, a novel multifunctional nano-snowflake probe (USPIO@MnO2@Ce6, UMC) for oxygen-enhanced photodynamic therapy was developed. We have fabricated the honeycomb-like MnO2 to co-load chlorin e6 (Ce6, a photosensitizer) and ultrasmall superparamagnetic iron oxide (USPIO, T1-T2 double contrast agent). Under the high H2O2 level of tumor cells, UMC efficiently degraded and triggered the exposure of photosensitizers to the generated oxygen, accelerating the production of reactive oxygen species (ROS) during PDT. Moreover, the resulting USPIO and Mn2+ allow for MR T1-T2 imaging and transformable PAI for multimodal imaging-guided tumor therapy.ResultsTEM and UV-vis spectroscopy results showed that nano-snowflake probe (UMC) was successfully synthesized, and the degradation of UMC was due to the pH/ H2O2 responsive properties. In vitro results indicated good uptake of UMC in 4T-1 cells, with maximal accumulation at 4 h. In vitro and in vivo experimental results showed their imaging capability for both T1-T2 MR and PA imaging, providing the potential for multimodal imaging-guided tumor therapy. Compared to the free Ce6, UMC exhibited enhanced treatment efficiency due to the production of O2 with the assistance of 660 nm laser irradiation. In vivo experiments confirmed that UMC achieved oxygenated PDT under MR/PA imaging guidance in tumor-bearing mice and significantly inhibited tumor growth in tumor-bearing mice, exhibiting good biocompatibility and minimal side effects.ConclusionThe multimodal imaging contrast agent (UMC) not only can be used for MR and PA imaging but also has oxygen-enhanced PDT capabilities. These results suggest that UMC may have a good potential for further clinical application in the future.

Targeted delivery of doxorubicin to tumor cells using engineered circular bivalent aptamer

Breast cancer is among the most frequent tumors in women and one of the main reasons of cancer death globally. Chemotherapy is among the leading cancer treatments, but because of its lack of selectivity, it can cause severe side effects. Therapeutic oligonucleotides and targeted drug delivery systems can largely overcome this problem. In this study, a targeted therapeutic complex containing doxorubicin (Dox), a chemotherapy drug, and AS1411 aptamer was designed using a circular bivalent system to treat breast cancer. The reason for naming the engineered circular bivalent aptamer system is the presence of AS1411 aptamers in circular shape on both sides of the system, and the engineered part includes a complementary sequence in the middle of the system. Finally, the therapeutic capability of the prepared targeted platform was assessed in vitro and in vivo. To prepare the system using two engineered AS1411 aptamers, both of them were incubated together at room temperature. Finally, a targeted therapeutic complex was formed by loading Dox between two complementary sequences. To analyze the properties and efficacy of the prepared complex, the loading rate of Dox in the complex, drug release at different pHs, and complex stability were verified. Also toxicity assay, flow cytometry analysis and fluorescence imaging were examined in nontarget cells (CHO cells, Chinese hamster ovary cells), and target cells (MCF-7 cells, human breast cancer cells, and 4T1 cells, mouse breast cancer cell). Also, the anti-tumor efficiency of the formulation was evaluated in mice bearing 4T1 tumor cells. The results showed that the targeted drug complex (Cb-Apt-Dox) has advantages such as high specificity for target cells, high stability in serum and simple preparation. According to results of the drug release test, the designed system is steady in the serum and blood environment. Cb-Apt-Dox could significantly increase cell uptake in MCF-7 and 4T1 cells (target, nucleolin positive) compared with CHO cells (nontarget, nucleolin negative). Based on the results of toxicity assay, Cb-Apt-Dox remarkably reduced cell viability in MCF-7 and 4T1 cells compared to CHO cells. Also, Cb-Apt-Dox significantly declined tumor growth in tumor-bearing mice compared to Dox and Cb-Apt. Our results verify that Cb-Apt-Dox can enhance antitumor effectiveness, minimize side effects of Dox and open up a new platform for breast cancer treatment.

Elastic Nanovaccine Enhances Dendritic Cell-Mediated Tumor Immunotherapy.

Nanovaccine-based immunotherapy (NBI) has the ability to initiate dendritic cell (DC)-mediated tumor-specific immune responses and maintain long-term antitumor immune memory. To date, the mechanism by which the mechanical properties of nanoparticles alter the functions of DCs in NBI remains largely unclear. Here, a soft mesoporous organosilica-based nanovaccine (SMONV) is prepared and the elasticity-dependent effect of the nanovaccine on the underlying DC-mediated immune responses is studied. It is found that the elasticity results in greater internalization of SMONV by DCs, followed by the induction of substantial cytosolic delivery of antigens via endosomal escape, leading to effective DC maturation and antigen cross-presentation. Impressively, elasticity enables SMONV to enhance lymphatic drainage of antigens in vivo, thus stimulating robust humoral and cellular immunity. The results from therapeutic tumor vaccination further reveal that subcutaneously administered SMONV effectively suppresses tumor growth in tumor-bearing mice by evoking antigen-specific CD8+ T-cell immune responses, mitigating regulatory T-cell-mediated immunosuppression, and increasing central memory and effector memory T-cell populations. Furthermore, combinatorial immunization with SMONV and anti-PD-L1 blocking antibodies results in an amplified therapeutic effect on tumor-bearing mice. These findings reveal the elastic effect of the nanovaccine on DC-mediated immune responses, and the prepared SMONV represents a facile and powerful strategy for antitumor immunotherapy.

Dendrobium officinale polysaccharide promotes M1 polarization of TAMs to inhibit tumor growth by targeting TLR2

Promoting M1 polarization of tumor-associated macrophages (TAMs) is an effective pathway for malignant tumor therapy. In this study, we aimed to demonstrate whether homogeneous Dendrobium officinale polysaccharide (DOP) could promote M1 polarization of TAMs to inhibit tumor growth, and how it promoted. Results exhibited that DOP could inhibit the tumor growth and promote the M1 polarization of TAMs in tumor-bearing mice. Macrophage depletion and replenishment experiment clearly proved that the inhibitory effect of DOP on tumor growth is dependent on promoting M1 polarization of TAMs. Moreover, we found that DOP could reach tumor microenvironment (TME) and directly bind to TAMs to promote its M1 polarization via targeting toll-like receptor 2 (TLR2) after oral administration. These results clarified that DOP could remarkably inhibit the tumor growth of tumor-bearing mice via directly targeting the TLR2 of TAMs to promote its M1 polarization.