Enhanced systemic tumor suppression by in situ vaccine combining radiation and OX40 agonist with CpG therapy.

BACKGROUND: In situ tumor vaccine has been gradually becoming a hot research field for its advantage of achieving personalized tumor therapy without prior antigen identification. Various in situ tumor vaccine regimens have been reported to exert considerable antitumor efficacy in preclinical and clinical studies. However, the design of in situ tumor vaccines still needs further optimization and the underlying immune mechanism also waits for deeper investigation. METHODS: A novel triple in situ vaccine strategy that combining local radiation with intratumoral injection of TLR9 agonist CpG and OX40 agonist was established in this sturdy. Local and abscopal antitumor efficacy as well as survival benefit were evaluated in the bilateral tumors and pulmonary metastasis model of B16F10 melanoma. In situ vaccine-induced immune responses and immune-associated variation in tumor environment were further investigated using multiparameter flow cytometry and RNA sequencing. Base on the analysis, the RT + CpG + αOX40 triple in situ vaccine was combined with checkpoint blockade therapy to explore the potential synergistic antitumor efficacy. RESULTS: Enhanced tumor suppression was observed with minimal toxicity in both treated and untreated abscopal tumors after receiving RT + CpG + αOX40 triple vaccine. The introduction of local radiation and OX40 agonist benefit more to the inhibition of local and abscopal lesions respectively, which might be partially attributed to the increase of effector memory T cells in the tumor microenvironment. Further analysis implied that the triple in situ vaccine did not only activate the microenvironment of treated tumors, with the upregulation of multiple immune-associated pathways, but also enhanced systemic antitumor responses, thus achieved superior systemic tumor control and survival benefit. Moreover, the triple in situ vaccine synergized with checkpoint blockade therapy, and significantly improved the therapeutic effect of anti-programmed cell death protein (PD)-1 antibody. CONCLUSION: This triple combining in situ vaccine induced intensive antitumor responses, mediated effective systemic tumor control and survival benefit, and displayed impressive synergistic antitumor effect with checkpoint blockade therapy. These data preliminary confirmed the efficacy, feasibility and safety of the triple combining in situ vaccine, suggesting its great application potential as both monotherapy and a part of combined immunotherapeutic regimens in clinical scenario.

Lymph node-targeted neoantigen nanovaccines potentiate anti-tumor immune responses of post-surgical melanoma.

BACKGROUND: Neoantigens are considered ideal targets for immunotherapy, especially tumor vaccine, because of their strong specificity and immunogenicity. Here, we developed a neoantigen nanovaccine used liposomes with lymph-node targeting characteristic. METHODS: Our nanovaccine was composed of neoantigens, an amphiphilic liposome and an adjuvant Montanide™ ISA 51. Small animal imaging system and immunofluorescence staining were used to identify the distribution of nanovaccines. A subcutaneous-tumor-resection mouse model of melanoma was established to evaluate the anti-tumor efficacy. Flow cytometry was performed to assay the immune responses initiated by nanovaccines. RESULTS: Nanovaccines could traffic to lymph nodes, be uptaken by CD11c+ DCs and promote DCs maturity. After the treatment of our neoantigen nanovaccines, the average recurrence time was extended from 11 to 16 days and the median survival time was even prolonged 7.5 days relative to the control group (NS group). Nanovaccines increased neoantigen-specific T cells to 10-fold of free vaccines, and upregulated Th1 cytokines, such as IFN-γ and TNF-α. The anti-tumor activity of spleen lymphocytes in the nanovaccine group was significantly stronger than that of other groups. However, some immune-inhibitory cells or molecules in tumor microenvironment have been detected upregulated under the immune pressure of neoantigen nanovaccines, such as Tregs and PD-L1. The efficacy of the neoantigen nanovaccine combined with anti-PD1 antibody or Treg inhibiting peptide P60 was better than that of the single treatment. CONCLUSIONS: We developed a general vaccine strategy, triggering specific T cell responses, and provided feasible combination strategies for better anti-tumor efficacy.

Tumor eradicated by combination of imiquimod and OX40 agonist for in situ vaccination.

Various cancer vaccines have been developed to generate and amplify antigen-specific T cell responses against malignancy. Among them, in situ vaccination is one of the most practical types as it can trigger immune responses without previous antigen identification. Here we reported a novel in situ vaccine by intratumoral injection of imiquimod and OX40 agonist. In mice bearing hepatic carcinoma, both the injected tumor and the noninjected tumor in the distant lesion of the same mice were suppressed after vaccination. Further studies found that this in situ vaccine triggered systemic tumor-specific responses, with one-fold increase of effector memory T cells properties and stronger toxicity of lymphocytes in spleen. Besides, we found that imiquimod upregulated the expression of OX40 on CD4+ T cells and thus enhanced the effectiveness of OX40 agonist. Five immune-positive-related pathways were activated after vaccination. This in situ vaccine caused little harm to normal organs and provided long-term protection against the same syngeneic tumor rechallenge. Due to its effectiveness, feasibility and safety, this strategy could potentially be applied to various types of late-stage solid tumors and worthy of further clinical research.

Monocrotophos detection with a bienzyme biosensor based on ionic-liquid-modified carbon nanotubes.

Acetylcholinesterase (AChE) biosensor technology is widely applied in the detection of organophosphate pesticides in agricultural production via the inhibition of AChE activity by organophosphates. However, the AChE electrode has some drawbacks, such as low stability and high overpotential. Combining the advantages of multiwalled carbon nanotubes (MWCNTs) and ionic liquids, we constructed a novel bienzyme electrode [Cl/iron porphyrin (FePP)-modified MWCNTs/AChE/glassy carbon electrode], which included AChE and mimetic oxidase FePP. In this electrode, FePP is covalently bound to the AChE carrier via ionic liquid for increased electrode sensitivity and stability. Under optimal conditions, this novel biosensor has a monocrotophos detection limit of 3.2 × 10-11 mol/L and good recovery of 89-104%. After 5 weeks of storage at 4 °C, the oxidation current was 97.8% of its original value. The biosensor has high stability and sensitivity for monocrotophos detection and is a promising device for monitoring food safety. Graphical abstract The complete synthesis process of Cl/FePP-MWCNTs/AChE/GCE.

[Infection of Giardia lamblia in HIV-Infected Individuals and in Kindergarden Children in Rural Area of Anhui and Genotype Analysis].

Objective: To understand the situation of Giardia lamblia infection in HIV-infected individuals and in kindergarden children in rural area of Anhui Province and analyze the genotype of the parasite. Methods: HIV-infected individuals registered in an AIDS treatment facility and children in a local kindergarden were included in this study during April 24 and May 9, 2015. The feces were collected, stained by iodine solution, and examined by microscopy. DNA was extracted from the positive feces, and nested PCR was performed to amplify the triosephosphate isomerase（tpi） gene of G. lamblia. The products were sequenced. The phylogenetic tree was constructed with BLAST, ClustalX 1.83 and MEGA6.0 softwares for analysis of homology and phylogeny. Results: One hundred and twenty-seven HIV-infected individuals and 125 kindergarden children were included. G. lamblia infection was found in three children and one HIV-infected individual. The infection detection rate in children and HIV patients was 2.40% （3/125） and 0.79% （1/127）, respectively （P>0.05）. Feces of the three infected children was soft, and no symptoms of diarrhea and stomachache were complained. Feces of the HIV-infected individual was washy, and symptoms like diarrhea, stomachache, weakness and weight loss were reported. PCR produced a specific band at 500 bp for the four persons. The sequencing results further confirmed infection in these four persons. The duplicate samples of the infected HIV patient had a 79% sequence similarity, and were 79% and 98% homologous to the Shanghai human strain of G. lamblia (GenBank accession No: KF271445), respectively. The samples of the 3 children had a 99% similarity, and all were 79% homologous to the Shanghai human strain of G. lamblia. The phylogenetic tree showed that the isolate from the HIV patient was mixed genotype of A+B, while those from the 3 children were all assemblage A. There was a high similarity between the isolates. Conclusions: There is Giardia infections in HIV patients and kindergarden children in the area. The genotype of the isolate from the HIV individual is mixed assemblage A+B while those from the children are assemblage A.

A Thermosensitive Bi-Adjuvant Hydrogel Triggers Epitope Spreading to Promote the Anti-Tumor Efficacy of Frameshift Neoantigens.

Tumor-specific frameshift mutations encoding peptides (FSPs) are highly immunogenic neoantigens for personalized cancer immunotherapy, while their clinical efficacy is limited by immunosuppressive tumor microenvironment (TME) and self-tolerance. Here, a thermosensitive hydrogel (FSP-RZ-BPH) delivering dual adjuvants R848 (TLR7/8 agonist) + Zn2+ (cGAS-STING agonist) is designed to promote the efficacy of FSPs on murine forestomach cancer (MFC). After peritumoral injection, FSP-RZ-BPH behaves as pH-responsive sustained drug release at sites near the tumor to effectively transform the immunosuppressive TME into an inflammatory type. FSP-RZ-BPH orchestrates innate and adaptive immunity to activate dendritic cells in tumor-draining lymph nodes and increase the number of FSPs-reactive effector memory T cells (TEM) in tumor by 2.9 folds. More importantly, these TEM also exhibit memory responses to nonvaccinated neoantigens on MFC. This epitope spreading effect contributes to reduce self-tolerance to maintain long-lasting anti-tumor immunity. In MFC suppressive model, FSP-RZ-BPH achieves 84.8% tumor inhibition rate and prolongs the survival of tumor-bearing mice with 57.1% complete response rate. As a preventive tumor vaccine, FSP-RZ-BPH can also significantly delay tumor growth. Overall, the work identifies frameshift MFC neoantigens for the first time and demonstrates the thermosensitive bi-adjuvant hydrogel as an effective strategy to boost bystander anti-tumor responses of frameshift neoantigens.

Membrane fusogenic nanoparticle-based HLA-peptide-addressing universal T cell receptor-engineered T (HAUL TCR-T) cell therapy in solid tumor.

T cell receptor-engineered T (TCR-T) cell therapy has demonstrated therapeutic effects in basic research and clinical trials for treating solid tumors. Due to the peptide-dependent recognition and the human leukocyte antigen (HLA)-restriction, TCR-T cell therapy is generally custom designed to target individual antigens. The lack of suitable universal targets for tumor cells significantly limits its clinical applications. Establishing a universal TCR-T treatment strategy is of great significance. This study designed and evaluated the HLA-peptide-addressing universal (HAUL) TCR-T cell therapy based on HLA-peptide (pHLA) loaded membrance fusogenic deliver system. The pHLA-NP-based tumor cell membrane modification technology can transfer the pHLA onto the surface of tumor cells through membrane fusogenic nanoparticles. Then tumor cells are recognized and killed by TCR-T cells specifically. The HAUL TCR-T cell therapy technology is a universal technology that enables tumor cells to be identified and killed by specific TCR-T cells, regardless of the HLA typing of tumor cells.

Nanomodified Switch Induced Precise and Moderate Activation of CAR-T Cells for Solid Tumors.

Chimeric antigen receptor (CAR)-T cell therapy is a transformative treatment against advanced malignancies. Unfortunately, once administrated in vivo, CAR-T cells become out of artificial control, and fierce response to CAR-T therapy may cause severe adverse events, represented by cytokine-release syndrome and on-target/off-tumor effects. Here, a nanomodified switch strategy is developed, leading to sustained and precise "on-tumor only" activation of CAR-T cells. Here, original gelatinase-responsive nanoparticles (NPs) are used to selectively deliver the heterodimerizing switch, which is the key component of switchable CAR with separated activation modules. The "NanoSwitch" is tumor-specific, thus inactivated switchable CAR-T cells do little harm to normal cells, even if the normal cells express the target of CAR-T. Owing to the sustained-release effect of NPs, the CAR-T cells are activated smoothly, avoiding sudden release of cytokine. These data introduce NanoSwitch as a universal and applicable solution to safety problems of CAR-T therapy regardless of the target.

[Establishment of the experimental animal model of Babesia microti].

OBJECTIVE: To establish the experimental animal model for the study of Babesia microti. METHODS: BALB/c mice, immunosuppressive BALB/c mice, SCID mice and NOD-SCID mice were inoculated with B. microti-infected red blood cells (RBC) by intraperitoneal injection respectively. After inoculation, thin blood smears were prepared every day, stained with Giemsa staining and examined for the presence of parasitemia. Three mice were dissected to examine the infectivity in bone marrow, brain, spleen, heart, lung, kidney and liver tissues. The infection rate of erythrocytes in different tissues was recorded, and the relationship between the infectivity of tissues and infection rate in peripheral blood was analyzed. Blood samples infected with B. microti were preserved in liquid nitrogen with dimethyl sulfoxide (DMSO) for 2 months. The thawed parasitized blood was injected into the BALB/c mice by same route and the parasitemia was monitored. RESULTS: The four kinds of mice were all infected by B. microti with parasitemia. The percentage of parasitized red blood cells from peripheral blood were 82.4% (BALB/c mice, d7), 73.2% (immunosuppressive BALB/c mice, d5), 86.4% (SCID mice, d8) and 72.5% (NOD-SCID mice, d8) at the maximum, respectively. Parasitemia decreased rapidly in BALB/c mice, whereas decreased slowly in immunosuppressive BALB/c mice. Only the parasitemia in SCID mice and NOD-SCID mice decreased significantly and tended to picking up again. The parasites were observed in RBCs from bone marrow, brain, spleen, heart, lung, kidney and liver tissues. The infection rate of erythrocytes in tissues increased with an increase of infection in peripheral blood. After cryopreservation, the parasites proliferated in BALB/c mice. Parasitemia appeared after inoculation with frozen infected blood two days later than that of fresh infected blood. The infection rate reached its peak after inoculation with frozen infected blood one day later than that of fresh infected blood. CONCLUSION: The experimental animal model of B. microti has been established. The infection rate of erythrocytes is related to the immune status of the host mice.

A dual-adjuvant neoantigen nanovaccine loaded with imiquimod and magnesium enhances anti-tumor immune responses of melanoma.

Neoantigen-based tumor vaccines have been applied in patient-specific melanoma-derived immunogenic mutated epitopes (neoantigens), with potential antineoplastic and immunomodulating effects. Yet, their use is limited by different physicochemical properties and poor pharmacokinetics. Herein, we constructed a human serum albumin-based dual adjuvant neoantigen nanovaccine loaded with imiquimod and magnesium. Magnesium, in coordination with imiquimod, could greatly activate dendritic and T cells. After subcutaneous injection, the nanovaccine effectively targeted tumor-draining lymph nodes (LNs) and promoted the presentation of neoantigens, thus generating a large number of effector T cells. In the B16F10 mouse melanoma prevention model, the nanovaccine effectively inhibited tumor growth and prolonged the survival time of tumor-bearing mice. To sum up, this new neoantigen nanovaccine could be used as a new method for targeting melanoma and may be potentially applied in clinical work.

China's 2060 carbon-neutrality agenda: the nexus between energy consumption and environmental quality.

This study examined the nexus between energy consumption and environmental quality in light of China's 2060 carbon-neutrality agenda utilizing annual frequency data from 1971 to 2018. In order to obtain valid and reliable outcomes, more robust econometric techniques were employed for the analysis. From the results, all the variables were first differenced stationary and cointegrated in the long-run. The elastic effects of the predictors on the explained variable were explored through the ARDL, FMOLS, and the DOLS techniques, and from the discoveries, energy utilization worsened environmental quality in the country via more CO2 emissions. Also, industrialization and urbanization deteriorated the country's environmental quality; however, technological innovations improved ecological quality in the nation. On the causal connections between the variables, a unidirectional causality from energy consumption to CO2 effluents was discovered. Also, feedback causalities between industrialization and CO2 secretions, and between urbanization and CO2 exudates were disclosed. However, there was no causality between technological innovations and CO2 emanations. Based on the findings, the study recommended among others that, since energy consumption pollutes the environment, the country should transition to the utilization of renewable energies. Also, the government should allocate more resources to the renewable energy sector. This will help increase the portion of clean energy in the country's total energy mix. Furthermore, research and development that are linked to the utilization of green energies should be supported by the government. Data constraints were the main limitation of this exploration. Therefore, in the future, if more data become available, similar explorations could be conducted to check the robustness of our study's outcomes.

Benefits of an Immunogenic Personalized Neoantigen Nanovaccine in Patients with High-Risk Gastric/Gastroesophageal Junction Cancer.

Personalized neoantigen vaccines have shown strong immunogenicity in clinical trial, but still face various challenges in facilitating an efficient antitumor immune response. Here, a personalized neoantigen nanovaccine (PNVAC) platform for adjuvant cancer immunotherapy is generated. PNVAC triggers superior protective efficacy against tumor recurrence and promotes longer survival than free neoantigens, especially when combined with anti-PD-1 treatment in a murine tumor model. A phase I clinical trial (ChiCTR1800017319) is initiated to evaluate the safety, immunogenicity, and prophylactic effect of PNVAC on preventing tumor recurrence in patients with high-risk gastric/gastroesophageal junction cancer after adjuvant chemotherapy of postsurgical resection. The one- and two-year disease-free survival rates are significantly higher than historical record. PNVAC induces both CD4+ and CD8+ T cell responses as well as antigen-experienced memory T cell phenotype. Furthermore, the immune response is persistent and remains evident one year after the vaccination. This work provides a safe and feasible strategy for developing neoantigen vaccines to delay gastric cancer recurrence after surgery.

Symptomatic and Asymptomatic Protist Infections in Hospital Inpatients in Southwestern China.

Cryptosporidium spp., Entamoeba histolytica, Giardia duodenalis, and Blastocystis sp. infections have been frequently reported as etiological agents for gastroenteritis, but also as common gut inhabitants in apparently healthy individuals. Between July 2016 and March 2017, stool samples (n = 507) were collected from randomly selected individuals (male/female ratio: 1.1, age range: 38-63 years) from two sentinel hospitals in Tengchong City Yunnan Province, China. Molecular (PCR and Sanger sequencing) methods were used to detect and genotype the investigated protist species. Carriage/infection rates were: Blastocystis sp. 9.5% (95% CI: 7.1-12.4%), G. duodenalis 2.2% (95% CI: 1.1-3.8%); and E. histolytica 2.0% (95% CI: 0.9-3.6%). Cryptosporidium spp. was not detected at all. Overall, 12.4% (95% CI: 9.7-15.6) of the participants harbored at least one enteric protist species. The most common coinfection was E. histolytica and Blastocystis sp. (1.0%; 95% CI: 0.3-2.2). Sequence analyses revealed that 90.9% (10/11) of the genotyped G. duodenalis isolates corresponded to the sub-assemblage AI. The remaining sequence (9.1%, 1/11) was identified as sub-assemblage BIV. Five different Blastocystis subtypes, including ST3 (43.7%, 21/48), ST1 (27.1%, 13/48), ST7 (18.8%, 9/48), ST4 (8.3%, 4/48), and ST2 (2.1%, 1/48) were identified. Statistical analyses confirmed that (i) the co-occurrence of protist infections was purely random, (ii) no associations were observed among the four protist species found, and (iii) neither their presence, individually or jointly, nor the patient's age was predictors for developing clinical symptoms associated with these infections. Overall, these protist mono- or coinfections are asymptomatic and do not follow any pattern.

[Study on the solid state transformation of PET/nano-CaCO3 composites by variable temperature FTIR spectroscopy].

Solid state transformation of crude poly (ethylene terephthalate)(PET) and PET/nano-CaCO3 (MPET) composites were studied by variable temperature FTIR spectroscopy during the heating process from 40 to 250 degrees C. The effects of nanometer calcium carbonate(nano-CaCO3) on the solid state transformation and crystal correlation bands of MPET composites were analyzed by the curves of the ratio of 1 342 and 1 410 cm(-1) absorbency(A1 342/A1 410) with temperature increasing, and together with DSC curves in the same condition. The results showed that the crystallization degrees of crude PET and MPET are obviously different in this condition by adding nano-CaCO3 particles as inhomogeneous nucleating agents.

Superior Antitumor Efficacy of IFN-α2b-Incorporated Photo-Cross-Linked Hydrogels Combined with T Cell Transfer and Low-Dose Irradiation Against Gastric Cancer.

INTRODUCTION: The exhaustion and poor homing of activated lymphocytes are critical obstacles in adoptive cell immunotherapy for solid tumors. In order to effectively deliver immune cells into tumors, we encapsulated interferon-α2b (IFN-α2b) into macroporous hydrogels as an enhancement factor and utilized low-dose irradiation (LDI) as a tumoral attractor of T cells. METHODS: Hydroxypropyl cellulose hydrogels were prepared by irradiation techniques, and the cross-sectional microstructure was characterized by scanning electron microscopy. The synergistic antitumor mechanism of combination of IFN-α2b and CIK cells was evaluated by detecting the expression of activation marker CD69 on CIK cell surface and IFN-γ production by CIK cells. The in vivo antitumor activity of IFN-α2b-incorporated hydroxypropyl cellulose hydrogels combined with CIK and radiation was evaluated in an MKN-45 xenografted nude mice model. RESULTS: The bioactivity of IFN-α2b was well maintained in ultraviolet-reactive, rapidly cross-linkable hydroxypropyl cellulose hydrogels. In vitro studies demonstrated IFN-α2b-activated T cells, as evidenced by upregulating early activation marker CD69 and secretion inflammatory cytokine IFN-γ. In vivo real-time image showed our hydrogels kept a higher amount of drug delivery at the tumor site for a long time compared with free drug injection. Low-dose irradiation promoted T cell accumulation and infiltration in subcutaneous tumors. Combination of IFN-α2b-loaded hydrogels (Gel-IFN) with T cells and LDI exhibited higher efficacy to eradicate human gastric cancer xenograted tumors with less proliferating cells and more necrotic regions compared with IFN-α2b or T cells alone. DISCUSSION: HPC hydrogels kept the activity of IFN-α2b and stably release of IFN-α2b to stimulate T cells for a long time. At the same time, low-dose radiation recruits T cells into tumors. This innovative integration mode of IFN-α2b-loaded hydrogels and radiotherapy offers a potent strategy to improve the therapeutic outcome of T cell therapy.

Molecular Epidemiology and Risk Factors of Blastocystis sp. Infections Among General Populations in Yunnan Province, Southwestern China.

BACKGROUND: Blastocystis is a common enteric parasite of controversial pathogenic roles in human diseases. Although the prevalence of Blastocystis infections has been investigated in a diverse range of populations, there is little knowledge on the molecular epidemiology and risk factors of Blastocystis infections among general populations in southeastern China. MATERIALS AND METHODS: A total of 507 individuals were randomly selected in Yunnan province, China from July 2016 to March 2017. Stool specimens were sampled for detection of Blastocystis sp. using PCR assay, and the risk factors of Blastocystis infections were identified. Blastocystis isolates were subtyped, and the associations of Blastocystis infections and subtypes with clinical manifestations were examined. RESULTS: The overall detection rate of Blastocystis sp. was 9.47% (95% CI: 7.13-12.44%). Toilet type (OR = 3.248, 95% CI: 1.245-8.473), anemia (OR = 2.601, 95% CI: 1.245-8.473) and type of daily drinking water (OR = 3.11, 95% CI: 1.557-6.213) were identified as risk factors of Blastocystis infections; however, Blastocystis infections showed no associations with clinical symptoms. Four subtypes (ST1 to ST4) were characterized in Blastocystis isolates, in which ST3 was predominant (4.73%, 95% CI: 3.2-6.94%), followed by ST1 (3.16%, 95% CI: 1.95-5.07%), ST4 (1.38%, 95% CI: 0.07-2.82%) and ST2 (0.2%, 95% CI: 0-1.11%). In addition, ST1 subtype infection was found to correlate with anemia (OR = 4.66, 95% CI: 1.631-14.314). CONCLUSIONS: There is a high prevalence of Blastocystis infections among general populations in Yunnan province, southwestern China, and toilet type, anemia and type of daily drinking water are risk factors of Blastocystis infections. ST3 is the dominant subtype of Blastocystis sp. characterized, and ST1 correlates with anemia. Improving hygiene conditions, developing healthy lifestyles and intensifying health education programs are strongly recommended to reduce the prevalence and transmission potential of Blastocystis infections.

MicroRNA-200c Nanoparticles Sensitized Gastric Cancer Cells to Radiotherapy by Regulating PD-L1 Expression and EMT.

INTRODUCTION: Immuno-checkpoint inhibitors (ICIs) in advanced gastric cancer either as monotherapy or in combining strategies are rapidly evolving but still in early phase. Various efforts have been made to provide insights into regulating immune checkpoint molecule programmed cell death ligand-1 (PD-L1) expression to improve ICIs efficacy. The aim of this study was to investigate the effect and potential mechanism of miR-200c nanoparticles combined with radiotherapy in gastric cancer cells. METHODS: We prepared miR-200c-loaded nanoparticles (miR-200c NPs) to achieve targeted delivery of miR-200c to AGS cells. The roles of miR-200c NPs and radiotherapy in regulating the viability of AGS cells were assessed by CCK-8 toxicity test and Annexin V-FITC/PI apoptosis kit. Flow cytometry was used to analyze expression of PD-L1 and CD44 on the surface of AGS cells treated by miR-200c NPs and/or ionizing radiation. Enzyme-linked immunosorbent assay (ELISA) was used to test the level of transforming growth factor-beta 1 (TGF-ß1) secreted by AGS cells. The cooperation mechanism between miR-200c NPs and radiotherapy was also explored in vitro. RESULTS: Compared with naked miR-200c mimics, miR-200c NPs significantly downregulated PD-L1 expression of gastric cancer cells. The combination of miR-200c NPs and radiotherapy showed significantly synergistic inhibitory effect on gastric cancer cells by inhibiting immune escape mediated by PD-L1, reversing EMT phenotype as well as abrogating cancer stem cells (CSCs)-associated properties of tumor cells. CONCLUSION: MiR-200c NPs sensitized gastric cancer cells to radiotherapy by regulating PD-L1 expression and EMT.

Antitumor Activity of Thermosensitive Hydrogels Packaging Gambogic Acid Nanoparticles and Tumor-Penetrating Peptide iRGD Against Gastric Cancer.

INTRODUCTION: Gambogic acid (GA) is proved to have anti-tumor effects on gastric cancer. Due to poor solubility, non-specific biological distribution, toxicity to normal tissues and short half-life, it is hard to be applied into the clinic. To overcome these issues, we developed a thermosensitive and injectable hydrogel composed of hydroxypropyl cellulose, silk fibroin and glycerol, with short gelling time, good compatibility and sustained release, and demonstrated that the hydrogel packaged with gambogic acid nanoparticles (GA-NPs) and tumor-penetrating peptide iRGD could improve the anti-tumor activity. METHODS: The Gelling time and micropore size of the hydrogels were regulated through different concentrations of glycerol. Controlled release characteristics of the hydrogels were evaluated with a real-time near-infrared fluorescence imaging system. Location of nanoparticles from different carriers was traced by confocal laser scanning microscopy. The in vivo antitumor activity of the hydrogels packaging GA-NPs and iRGD was evaluated by investigating tumor volume and tumor size. RESULTS: The thermo-sensitive properties of hydrogels were characterized by 3-4 min, 37°C, when glycerol concentration was 20%. The hydrogels physically packaged with GA-NPs and iRGD showed higher fluorescence intensity than other groups. The in vivo study indicated that the co-administration of GA-NPs and iRGD by hydrogels had higher antitumor activity than the GA-loaded hydrogels and free GA combining with iRGD. Free GA group showed few antitumor effects. Compared with the control group, the body weight in other groups had no obvious change, and the count of leukocytes and hemoglobin was slightly decreased. DISCUSSION: The hydrogel constructed iRGD and GA-NPs exerted an effective anti-tumor effect possibly due to retention effect, local administration and continuous sustained release of iRGD promoting the penetration of nanoparticles into a deep part of tumors. The delivery system showed little systemic toxicity and would provide a promising strategy to improve anti-gastric cancer efficacy.

Prevalence and risk factors of Fascioliasis in China.

Fascioliasis has emerged as a significant public health problem among ruminants and humans. Human fascioliasis is a neglected food-borne parasitic disease, which has emerged or reemerged in more than 60 countries worldwide. In China, the first case of human fascioliasis was reported in 1921 in Fujian Province. The first major outbreak of this parasitic disease in 29 patients occurred in 2012 in Yunnan Province. Nonetheless, the prevalence of fascioliasis in China is probably underestimated due to the poor sensitivity of diagnostic tests, limited epidemiological data, and a poor understanding of the impact of subclinical illness. This study aimed to review the prevalence and risk factors of fascioliasis in China so as to improve the prevention and control of this disease.