Preliminary Validation of Tumor Cell Attachment Inhibition Assay for Developmental Toxicants With Mouse S180 Cells

This study was designed to explore the possibility of using ascitic mouse sarcoma cell line (S180) to validate the mouse tumor cell attachment assay for developmental toxicants, and to test the inhibitory effects of various developmental toxicants. The results showed that 2 of 3 developmental toxicants under consideration, sodium pentobarbital and ethanol, significantly inhibited S180cells attachment to Concanavalin A-coaed surfaces. Inhibition was dependent on concentration, and the IC50 (the concentration tha reduced attachment by 50% ), of these 2 chemicals was 1.2×10-3mol/L and 1 .0 mol/L, respectively. Anoher developmental toxiant, hydmiortisone, did not show inhibitory activity. Two non-developmental toxicants, sodium chloride and glycine were also tested and these did not decrease attachment rates. The main results reported here were generally sindlar to those obtained with ascitic mouse ovdrian tumor cells as a model. Therefore, this study added further evidence to the conclusion that cell specificity does not lindt attachment inhibition to Con A-coated surfaces, so S180 cell may serve as an altemative cell model, especially when other cell lines are unavailable. Furthermore, after optimal validation, it can be suggested that an S180 cell attachment assay may be a candidate for a series of assays to detect developmental toxicants.

Inhibition of tumor angiogenesis by TTF1 from extract of herbal medicine

AIM:To study the inhibition of tumor angiogenesis by 5,2,4'-trihydroxy-6,7,5'-trimethoxyflavone(TTF1) isolated from an extract of herbal medicine Sorbaria sorbifolia.METHODS:Angiogenic activity was assayed using the chick embryo chorioallantoic membrane(CAM) method.Microvessel density(MVD) was determined by staining tissue sections immunohistochemically for CD34 using the Weidner capillary counting method.The mRNA and protein levels of vascular endothelial growth factor(VEGF),vascular endothelialgrowth factor receptor 2(VEGFR2,Flk-1/KDR),basic fibroblast growth factor(bFGF),cyclo-oxygenase(COX)-2 and hypoxia-inducible factor(HIF)-1α were detected by quantitative real-time polymerase chain reaction and Western blotting analysis.RESULTS:The TTF1 inhibition rates for CAM were 30.8%,38.2% and 47.5% with treatment concentrations of 25,50 and 100 μg/embryo × 5 d,respectively.The inhibitory rates for tumor size were 43.8%,49.4% and 59.6% at TTF1 treatment concentrations of 5,10,and 20 μmol/kg,respectively.The average MVD was 14.2,11.2 and 8.5 at treatment concentrations of 5 μmol/kg,10 μmol/kg and 20 μmol/kg TTF1,respectively.The mRNA and protein levels of VEGF,KDR,bFGF,COX-2 and HIF-1α in mice treated with TTF1 were significantly decreased.CONCLUSION:TTF1 can inhibit tumor angiogenesis,and the mechanism may be associated with the down-regulation of VEGF,KDR,bFGF,HIF-1α and COX-2.

Tumor microenvironment-activatable neuropeptide-drug conjugates enhanced tumor penetration and inhibition via multiple delivery pathways and calcium deposition

Peptide-drug conjugates have achieved considerable development and application as a novel strategy for targeted delivery of anticancer drugs. Bioactive peptides induced calcium deposition can irreversibly assist inhibition of tumors. However, active regulation of calcium level through signal transduction of bioactive substances has not been reported yet. In this study, novel neuropeptide-doxorubicin conjugates(NP-DOX) with lysosome-specific acid response were described for neuropeptide Y_1 receptor(Y_1R)-overexpressed triple-negative breast cancer. The delivery mechanism of NP-DOX was clarified that diverse pathways were involved, including intracellular and intercellular transport. Importantly, up-regulation of Y_1 R-mediated intracellular calcium level via second messenger inositol triphosphate was presented in NP-DOX treated MDA-MB-231 cells. In vivo antitumor efficacy demonstrated that NP-DOX showed less organ toxicity and enhanced tumor inhibition benefited from its controlled release and Y_1R-mediated calcium deposition, compared with free DOX. This bioconjugate is a proof-of-concept confirming that neuropeptide-mediated control of signaling responses in neuropeptide-drug conjugates enables great potential for further applications in tumor chemotherapy.

Astragalus polysaccharides can regulate cytokine and P-glycoprotein expression in H22 tumor-bearing mice

AIM:To investigate the adjunct anticancer effect of Astragalus polysaccharides in H22 tumor-bearing mice.METHODS:To establish a solid tumor model,5.0 × 10 6 /mL H22 hepatoma cells were inoculated subcutaneously into the right armpit region of Kunming mice(6-12 wk old,18-22 g).When the tumors reached a size of 100 mm 3,the animals were treated as indicated,and the mice were randomly assigned to seven groups(n = 10 each).After ten days of treatment,blood samples were collected from mouse eyes,and serum was harvested by centrifugation.Mice were sacrificed,and the whole body,tumor,spleen and thymus were weighed immediately.The rate of tumor inhibition and organ indexes were calculated.The expression levels of serum cytokines,P-glycoprotein(P-GP) and multidrug resistance(MDR) 1 mRNA in tumor tissues were detected using enzyme-linked immunosorbent assay,Western blotting,and quantitative myeloid-derived suppressor cells reverse transcription-polymerase chain reaction,respectively.RESULTS:The tumor inhibition rates in the treatment groups of Adriamycin(ADM) + Astragalus polysaccharides(APS)(50 mg/kg),ADM + APS(100 mg/kg),and ADM + APS(200 mg/kg) were significantly higher than in the ADM group(72.88% vs 60.36%,P = 0.013;73.40% vs 60.36%,P = 0.010;77.57% vs 60.36%,P = 0.001).The spleen indexes of the above groups were also significantly higher than in the ADM group(0.65 ± 0.22 vs 0.39 ± 0.17,P = 0.023;0.62 ± 0.34 vs 0.39 ± 0.17,P = 0.022;0.67 ± 0.20 vs 0.39 ± 0.17,P = 0.012),and the thymus indexes of the ADM + APS(100 mg/kg) and ADM + APS(200 mg/kg) groups were significantly higher than in the ADM group(0.20 ± 0.06 vs 0.13 ± 0.04,P = 0.029;0.47 ± 0.12 vs 0.13 ± 0.04,P = 0.000).APS was found to exert a synergistic antitumor effect with ADM and to alleviate the decrease in the sizes of the spleen and thymus induced by AMD.The expression of interleukin-1α(IL-1α),IL-2,IL-6,and tumor necrosis factor-α(TNF-α) was significantly higher in the ADM + APS(50 mg/kg),ADM + APS(100 mg/kg) and ADM + APS(200 mg/kg) groups than in the ADM group;and IL-10 was significantly lower in the above groups than in the ADM group.APS could increase IL-1α,IL-2,IL-6,and TNF-α expression and decrease IL-10 levels.Compared with the ADM group,APS treatment at a dose of 50-200 mg/kg could downregulate MDR1 mRNA expression in a dose-dependent manner(0.48 ± 0.13 vs 4.26 ± 1.51,P = 0.000;0.36 ± 0.03 vs 4.26 ± 1.51,P = 0.000;0.21 ± 0.04 vs 4.26 ± 1.51,P = 0.000).The expression level of P-GP was significantly lower in the ADM + APS(200 mg/kg) group than in the ADM group(137.35 ± 9.20 mg/kg vs 282.19 ± 20.54 mg/kg,P = 0.023).CONCLUSION:APS exerts a synergistic anti-tumor effect with ADM in H22 tumor-bearing mice.This may be related to its ability to enhance the expression of IL1α,IL-2,IL-6,and TNF-α,decrease IL-10,and downregulate MDR1 mRNA and P-GP expression levels.

Trojan horses in tumor:engineered pyroelectric and photodynamic nanocomposites for NIR-induced cell apoptosis and tumor growth inhibition

It is desirable but always challenging to develop a cutting-edge tumor treatment strategy with high therapeutic efficacy,lesiontargeted precision and mild accessibility.Compared to traditional treatment modalities,photodynamic therapy has been widely studied since the generation of reactive oxygen species(ROS)at cancerous lesions unprecedentedly offers a convenient approach for localized tumor eliminations.Nevertheless,the consumption of oxygen for ROS production in a hypoxic tumor microenvironment has dramatically limited its feasibility and efficacy.Herein,the engineered nanocomposites of BTO@PDA-ICGHA with photodynamic and pyroelectric performances have been fabricated and applied to the photodynamic-pyroelectric dynamic treatments.The continuing ROS production derived from intracellular oxygen(O_(2))and water(H_(2)O)by laser irradiation contributed to the superb tumor cell apoptosis and significant tumor growth inhibition.Thus,this study has validated a new concept by depositing the engineered nanocomposites at the tumor just like Trojan horses,facilitating ROS release as killers and exerting the NIR-induced cell apoptosis and tumor growth inhibition with high therapeutic efficiency and expectable translational perspectives.

Effect of grape proanthocyanidins on tumor growth and angiogenesis in H22 liver cancer xenograft model

Objective: The aim of this study was to investigate the effect of grape proanthocyanidins(GPC) on the growth and angiogenesis of hepatocellular carcinoma H22 cells xenograft in mice. Methods: The xenograft model was established using injected subcutaneously H22 cells into the right axilla of the mice. Each group was treated with different doses of GPC and Endostar. All these treatments were maintained for 10 days, and mice were sacrificed. The xenograft tumors in mice were measured. The proliferation activity level of H22 cells was determined by MTT assay, and the levels of vascular endothelial growth factor(VEGF) protein were examined by immunohistochemistry. Results: When treated with 50, 100 and 200 mg/kg of GPC and Endostar, the tumor inhibition rates were 13.17%, 23.37%, 36.15% and 14.71%, respectively. The tumor weight of xenograft was significantly lighter in high GPC group than the control group(P < 0.05). The ODs in GPC groups were 0.835, 0.666 and 0.519, respectively. The absorbances in middle and high GPC groups were statistically significant, compared with control group(P < 0.01). Immunohistochemical technique showed the expression of VEGF of the GPC groups was downregulated significantly compared with the control group(P < 0.01). Conclusion: GPC can inhibit the growth of hepatocellular carcinoma H22 cell xenograft in mice. The inhibition of angiogenesis by the down-regulation of VEGF expression may play a key role in the anti-neoplastic effect of GPC.

ANTITUMOR MECHANISM OF GEM10 BY THE NATURAL KILLER ACTIVITY AND INTERLEUKIN-2 PRODUCTION

Objective To investigate th e anti-tumor effects of GeM10 by the natural killer(NK) cells activities and th e production of Interleukin-2 (IL-2) in peripheral blood mononuclear cells (PB MNCs). Methods Assay of human NK cells activities by dye reject ion assay in vitro and production of IL-2 in PBMNC by IL-2 bioassay with I L-2 dependent cell line CTLL2 and MTT colorometric method. Results GeM10 could significantly stimulate NK activities (60μg·mL -1 G eM10: 17.077±7.665, 120μg·mL -1 GeM10: 24.9±13.04; control: 7.72±4 .64, P< 0.05). GeM10 could up-regulate the production of IL-2 of PBMNCs in tumor patients(60μg·mL -1 GeM10: 2.965± 1.183; 120μg·mL -1 GeM10: 2.28±0.847; control: 1.792±0.823, P<0.05).Conclu si on The GeM10 not only can stimulate the NK activities but also increase the IL-2 production by PBMNCs in tumor patients. These findings indicate that the GeM10 may have promise as an anti-tumor drug and a biological response modi fier in clinic.

Nanomaterials for visualized tumor surgical navigation and postoperative recurrence inhibition

Preoperative localization of the tumor sites and intraoperative real-time monitoring are essential for precise surgery but are meanwhile challenging due to the lack of high-resolution,easy-to-operate,and fast visualization techniques.On the other hand,tumor recurrence and metastasis after surgery greatly reduce the survival rate of patients.Intervening tumor recurrence during surgery is a future direction of tumor treatment.Nanomaterials with external condition responsiveness(light,ultrasound,and magnetic field)can accurately assist intraoperative detection and surgical resection due to their functions such as tumor cell targeting,fluorescence imaging,and real time monitoring,providing a more accurate,shorter duration,and visualization method of surgical resection.Moreover,nanomaterials are versatile and can easily be tailored for application in different tumors.Locally filled or systemically circulating nanomaterials with slow drug release and residual tumor cell-targeting ability have promising applications in inhibiting tumor recurrence.Here,we review surgical navigation and postoperative recurrence interventional nanomaterials and their landscape in guiding tumor treatment.We summarize the classification and characteristics of these nanomaterials and discuss their application in the surgical navigation and recurrence inhibition of different tumors.We also provide an outlook on the challenges and future development of nanomaterials for visualized tumor surgical navigation and postoperative recurrence inhibition.

Inhibitory Effect of Buddlejasaponin Ⅳ on Hepatocarcinoma 22(H_(22)) in Mice

[Objective] This study aimed to investigate the inhibitory effect of buddle- jasaponin IV on growth of hepatocarcinoma 22 （H22） tumor in mice. [Method] The H= tumor cells were transplanted in the right axillary skins of mice. The tumor- bearing mice were randomly divided into five groups, including control group, CTX group （20.0 mg/kg） and buddlejasaponin IV treatment groups （0.25, 0.50 and 1.00 mg/kg）. There were 10 mice in each group. During the treatment, the body weights and survivals of mice in all groups were recorded. The buddlejasaponin IV was in- jected into the abdominal cavities of mice, which lasted for 10 consecutive days. All the mice were slaughtered the next day. The tumors in the abdominal cavities were tanked out and weighed. The tumor inhibition rate, spleen index and thymus index, as well as SOD activity, MDA content, GGT activity and AKP activity in serum were determined. [Result] Compared with the control group, the high- and middle- dosage buddlejasaponin IV treatment groups all showed significant （P〈0.01） inhibito- ry effects on transplanted H22 tumor in mice with tumor inhibition rates of 56.96% and 50.63%, respectively. Compared with those in the control group, the SOD ac- tivity of mice in the high-dosage buddlejasaponin IV treatment group was significant- ly increased （P〈0.05）, and the MDA contents, GGT and AKP activities in mice in the high-, middle- and low-dosage buddlejasaponin IV treatment groups were all sig- nificantly reduced （P〈0.01）. There were no significant differences in all the indexes, except SOD activity, between the CTX and control groups. [Conclusion] Buddlejas- aponin IV has certain inhibitory effect on H22 tumor, of which the mechanism might be related to antioxidation capacity in body.

Ensemble of single-atom catalysis and defect engineering in Cu_(1)/CeO_(2) nanozymes for tumor therapy

As a class of nanomaterials with natural enzyme-like characteristics, nanozymes have shown their great potential in various applications. Reducible metal oxides featured with defect structures, and single-atom catalysts with isolated metal sites are regarded as two of the most promising nanozymes. However, the strategies to construct highly performed nanozymes by combining these advantages are rarely reported. Herein, we report the coordination-unsaturated single-atomic Cu species supported on sintered CeO_(2), which combines the advantages of defect engineering and single-atom catalysis, exhibiting a largely enhanced peroxidase(POD)-like activity. The high-temperature calcination induces the transformation of inert Cu_(1)O_(4) species into coordination-unsaturated Cu_(1)O_(3) sites. This novel Cu_(1)O_(3) active sites with an unsaturated coordination work as a new type of defect sites to greatly activate the isolated Cu atoms and accelerate the dissociation of H_(2)O_(2) to form hydroxyl radicals(·OH). The obtained nanozyme with a high POD-like activity possesses low cytotoxicity, showing potential applications for the tumor inhibition in vitro and in vivo.

Inhibitory effect of arsenic trioxide on angiogenesis and expression of vascular endothelial growth factor in gastric cancer

AIM: To investigate the inhibitory effect of As2O3 on angiogenesis of tumor and expression of vascular endothelial growth factor (VEGF) in tumor cells in vivo and in vitro. METHODS: The solid tumor model was formed in nude mice with the gastric cancer cell line SGC-7901. The animals were randomly divided into three groups. As2O3 was injected into the arsenic-treated groups (2.5 mg/kg and 5 mg/kg) and the same volume of saline solution was injected into the control group. Microvessel density (MVD) and expression of VEGF were detected with immunofluorescence laser confocal technology. Further expression of VEGF protein and VEGF mRNA was measured with Western bloting and fluorescence quantitative RT- PCR in SGC-7901 cells treated with As2O3. RESULTS: In nude mice, after treatment with 5 mg/kg and 2.5 mg/kg As2O3 respectively, about 50% and 30% tumor growth inhibition were observed correspondingly (P < 0.05, P < 0.05). Decrease in MVD appeared in As2O3-treated tumors compared with control group (P < 0.001, P < 0.001). MVD in tumors was significantly lower in 5 mg/kg group than in 2.5 mg/kg group (P < 0.01). The fluorescence intensity levels of VEGF in tumor cells were significantly lowered in the arsenic-treated groups (P < 0.01, P < 0.01). The fluorescence intensity level of VEGF in 5 mg/kg group was lower than that in 2.5 mg/ kg group (P < 0.01). In vitro, the expression of VEGF protein decreased in dose- and time-dependent manner after the treatment with As2O3, but in VEGF mRNA no significant difference was found between the control group and the treated groups. CONCLUSION: As2O3 can inhibit solid tumor growth by inhibiting the formation of new blood vessels. One of the mechanisms is that As2O3 can inhibit VEGF protein expression.

Effect of arsenic trioxide on vascular endothelial cell proliferation and expression of vascular endothelial growth factor receptors Flt-1 and KDR in gastric cancer in nude mice

AIM： To investigate the effect of arsenic trioxide （As2O3） on expression of vascular endothelial growth factor receptor-1 （VEGFR-1, Flt-1） and VEGFR-2 （KDR） in human gastric tumor cells and proliferation of vascular endothelial cells.METHODS： The solid tumor model was formed in nude mice with the gastric cancer cell line SGC-7901. The animals were treated with As2O3. Microvessel density （MVD） and expression of Flt-1 and KDR were detected by immunofluorescence laser confocal microscopy. SGC-7901 cells were treated respectively by exogenous recombinant human VEGF165 or VEGF165 ＋ As2O3. Cell viability was measured by MTT assay. Cell viability of ECV304 cells was measured by MTT assay, and cell cycle and apoptosis were analyzed using flow cytometry.RESULTS： The tumor growth inhibition was 30.33% and 50.85%, respectively, in mice treated with As2O3 2.5 and 5 mg/kg. MVD was significantly lower in arsenic-treated mice than in the control group. The fluorescence intensity levels of Flt-1 and KDR were significantly less in the arsenic-treated mice than in the control group. VEGF165 may accelerate growth of SGC7901 cells, but As2O3 may disturb the stimulating effect of VEGF165. ECV304 cell growth was suppressed by 76.51%, 71.09% and 61.49% after 48 h treatment with As2O3 at 0.5, 2.5 and 5 μmol/L, respectively. Early apoptosis in the As2O3- treated mice was 2.88-5.1 times higher than that in the controls, and late apoptosis was 1.17-1.67 times higher than that in the controls.CONCLUSION： Our results showed that As2O3 delays tumor growth, inhibits MVD, down-regulates Flt-1 and KDR expression, and disturbs the stimulating effect of VEGF165 on the growth of SGC7901 cells. These results suggest that As2O3 might delay growth of gastric tumors through inhibiting the paracrine and autocrine pathways of VEGF/VEGFRs.

Preparation of chitosan-Epigallocatechin-3-O-gallate nanoparticles and their inhibitory effect on the growth of breast cancer cells

In this paper,we prepared the nanoparticle drug carrier system between nanoparticles chitosan and Epigallocatechin-3 O-gallate(EGCG)for breast cancer cell inhibiting application.For this drug carrier system,chitosan acts as a carrier and EGOG as a drug.Which were systematically characterized and thoroughly evaluated in terms of their inhibition rate and biocompatibility.We also did a cell scratch test and the result indicated that the chitosan EGCG nanoparticles have inhibitory effect on the growth of breast cancer cells.The inhibition rate could reach up to 21.91%.This work revealed that the modification of nanopartidles paved a way for specific biomedical applications.

Ovarian growing teratoma syndrome with multiple metastases in the abdominal cavity and liver:A case report

BACKGROUND Growing teratoma syndrome(GTS)is an unusual presentation of an amazing transformation of teratoma from malignant to benign on pathology during or after systemic or intraperitoneal chemotherapy.The definitive pathogenesis is still not fully understood due to the lack of large-sample studies.CASE SUMMARY A 53-year-old woman underwent radical surgery and postoperative intraperitoneal chemotherapy due to immature teratoma of the right ovary at the age of 28.She remained well during a 25-year follow-up period after surgery.Multiple asymptomatic solid masses were found in the liver on ultrasonography a month ago.Enhanced computed tomography(CT)of the abdomen revealed multiple masses in the abdominal cavity.The largest one was located in the posterior peritoneum next to the sixth segment of the right liver,about 7.9 cm×7.5 cm in size.Three masses were present inside the liver,and one mass was in the right pelvic floor.Multiple lumps in the abdominal cavity were completely removed by surgery.During the operation,multiple space-occupying lesions were seen,ranging in size from 0.5 to 3 cm,and grayish white in color and hard in texture.Ovarian GTS was finally diagnosed based on postoperative pathology.After surgery,she recovered uneventfully.During a 3-year follow-up,the patient remained free of the disease without any recurrence on CT scan.CONCLUSION GTS is a rare phenomenon characterized by conversion of immature teratoma to mature one during or after chemotherapy and presents as growing and metastasizing masses.The pathogenesis of GTS is unclear,and the prognosis is good after surgical resection.

Comparative antitumor and anti-proliferative activities of Hippophae rhamnoides L. leaves extracts

Objective:To evaluate the antitumor and anti-proliferative activities of methanol,aqueous,acetone,ethyl acetate,ethanol,chloroform and n-hexane extracts of Hippophae rhamnoides leaves.Methods:Antitumor activities were evaluated by using the antitumor potato disc assay by using inoculums(Agrobacterium tumefaciens)with three different concentrations of test samples(10,100 and 1000 mg/L).Anti-proliferative activity was evaluated by the given method of methyl thiazolyl tetrazolium assay.The concentrations of the extract ranging from 0.039 to 10 mg/mL were tested against HeLa cells.Results:Highest tumors inhibition activity(60.9%and 55.8%)was shown by methanol and ethanol extracts,with EC_(50) values of 424.41 and 434.61 mg/L respectively.At 10 mg/mL,The highest cell inhibition 75.61%was observed in methanol extract and the lowest 36.59%were calculated in n-hexane extract.The difference in tumor and cell inhibition(%)may be due to the different concentration of active compounds responsible for antitumor and anti-proliferative activities.All extracts have considerable level of tumor and cell inhibitiory effect in a dose dependent manner.Conclusions:Our finding showed that Hippophae rhamnoides leaves are a potent natural source of antitumor and antiproliferative agent.

A site-oriented nanosystem for active transcellular chemo-immunotherapy to prevent tumor growth and metastasis

Immunotherapy has shown promising potential in cancer therapy;however, poor delivery by nanocarriers and insufficient immune response in tumors have severely impeded its clinical application. To overcome these disadvantages, a site-specific and active transcellular drug delivery system was developed herein for chemotherapyenhanced immunotherapy. When arriving at the tumor site,the matrix metallopeptidase 2(MMP2)-responsive shell detached from the nanosystem, releasing positively charged cores. The cationic surface of the inner cores induced adsorption-meditated transcytosis, which facilitated transendothelial transportation and transcellular drug delivery into distal tumor cells. PD-L1 antibody and chemotherapeutic drugs were loaded in the outer layer and inner cores of the nanosystem, respectively, to be precisely delivered to target sites, thereby achieving synchronized delivery and siteoriented release of different anticancer agents. PD-L1 antibody released in the tumor microenvironment effectively blocked the binding of PD-L1 to its receptors on the T cell surface. Oxaliplatin and indoximod co-delivered in the cationic cores can induce immunogenic cell death and attenuate the immunosuppressive effect throughout the tumor tissues,recruiting a large amount of T cells and further enhancing the immunotherapy. The resulting synergistic antitumor response could not only efficiently inhibit the growth of primary tumors, but also help prevent metastasis of primary tumor to distant sites. This study offers a novel nano-enabled strategy for chemo-immunotherapy in immunosuppressive tumors.

Intelligent nanoreactor coupling tumor microenvironment manipulation and H_(2)O_(2)-dependent photothermal-chemodynamic therapy for accurate treatment of primary and metastatic tumors

Tumor microenvironment(TME),as the“soil”of tumor growth and metastasis,exhibits significant differences from normal physiological conditions.However,how to manipulate the distinctions to achieve the accurate therapy of primary and metastatic tumors is still a challenge.Herein,an innovative nanoreactor(AH@MBTF)is developed to utilize the apparent differences(copper concentration and H_(2)O_(2)level)between tumor cells and normal cells to eliminate primary tumor based on H_(2)O_(2)-dependent photothermal-chemodynamic therapy and suppress metastatic tumor through copper complexation.This nanoreactor is constructed using functionalized MSN incorporating benzoyl thiourea(BTU),triphenylphosphine(TPP),and folic acid(FA),while being co-loaded with horseradish peroxidase(HRP)and its substrate ABTS.During therapy,the BTU moieties on AH@MBTF could capture excessive copper(highly correlated with tumor metastasis),presenting exceptional anti-metastasis activity.Simultaneously,the complexation between BTU and copper triggers the formation of cuprous ions,which further react with H_(2)O_(2)to generate cytotoxic hydroxyl radical(•OH),inhibiting tumor growth via che-modynamic therapy.Additionally,the stepwise targeting of FA and TPP guides AH@MBTF to accurately accu-mulate in tumor mitochondria,containing abnormally high levels of H_(2)O_(2).As a catalyst,HRP mediates the oxidation reaction between ABTS and H_(2)O_(2)to yield activated ABTS•^(+).Upon 808 nm laser irradiation,the activated ABTS•^(+)performs tumor-specific photothermal therapy,achieving the ablation of primary tumor by raising the tissue temperature.Collectively,this intelligent nanoreactor possesses profound potential in inhib-iting tumor progression and metastasis.

Anti-melanoma effect and action mechanism of a novel chitosan-based composite hydrogel containing hydroxyapatite nanoparticles

Hydroxyapatite nanoparticles(HANPs)have been increasingly regarded and reported due to their potential anti-tumor ability.Previously,we found that the rod-like HANPs had good application potential for cutaneous melanoma(CMM).To satisfy the actual requirements in repairing post-operative skin defects and inhibiting CMM recurrence after tumorectomy,we constructed a novel chitosan/alginate(CS/Alg)hydrogel containing the aforementioned HANPs.The in vitro cell experiments confirmed that activated mitochondrial-dependent apoptosis was tightly related to the anti-tumor ability of HANPs.Specifically,we further discovered several target proteins might be involved in abnormal activating Wnt,proteoglycans in cancer,oxidative phosphorylation and p53 signaling pathways.The in vivo animal experiments demonstrated that the HANPsloaded CS/Alg hydrogel(CS/Alg/HANPs)had a similar effect on inhibiting tumor growth as HANPs,and CS/Alg hydrogel as well as phosphate buffered saline(PBS)group(control)not showed any effect,proving the key role of HANPs.The immunohistochemical staining demonstrated a tumor inhibition via the mitochondria-mediated apoptosis pathway,consistent with the in vitro evaluation.Moreover,CS/Alg/HANPs exhibited no additional biosafety risk to the functions of major organs.Overall,this CS/Alg/HANPs hydrogel has substantial application potential for treating CMM.