Animals ; COS Cells ; Female ; Genetic Therapy ; Interleukin-12 ; genetics ; Liver Neoplasms, Experimental ; immunology ; therapy ; Mice ; Mice, Inbred BALB C ; T-Lymphocytes, Cytotoxic ; immunology

OBJECTIVETo observe the in vivo antitumor activity of murine liver tumor vaccine expressing MIP-1alpha mediated by recombinant adenoviral vector.

METHODSThe infection efficacy was measured by GFP expression 48 hours after infection of Hepa1-6, and the number of cells was counted daily for 14 days. 5 x 10(6) modified Hepa1-6 cells were inoculated subcutaneously to C57BL/6 mice and the tumor-free animals were rechallenged by 2 x 10(6) wild-type Hepa1-6 cells or syngenic EL4 cells four weeks later. The tumor volume was measured twice a week.

RESULTSAdenoviral vectors could efficiently infect Hepa1-6 cells in vitro, and the in vitro growth rate of AdmMIP-1alpha modified Hepa1-6 cells was not affected; however the in vivo tumorigenicity was significantly decreased, compared with that of control vector modified Hepa1-6. Rechallenge of the tumor-free mice four weeks after administration of AdmMIP-1alpha with the parental Hepa1-6 cells resulted in significant inhibition of tumor growth, but there was no significant difference when rechallenged with EL4.

CONCLUSIONSThe liver cancer cells expressing mMIP-1alpha mediated by recombinant adenoviral vector decrease tumorigenicity and elicit specific immunological protection, and could be used as an effective liver tumor vaccine.

Adenoviridae ; genetics ; Animals ; Cancer Vaccines ; immunology ; Chemokine CCL3 ; Chemokine CCL4 ; Genetic Therapy ; Liver Neoplasms, Experimental ; therapy ; Macrophage Inflammatory Proteins ; genetics ; Mice ; Mice, Inbred C57BL ; Vaccines, Synthetic ; immunology

OBJECTIVETo investigate the immunotherapy efficacy of both helper T lymphocytes (Th) and cytotoxic T lymphocytes (CTL) epitopes augmented dendritic cells (DCs) tumor vaccine on gastric cancer.

METHODSNaïve spleen T cells were stimulated by mixed peptides (a mixture of Th epitope MAGE-3 (22-36)) primed DCs per week in vitro. After 4 cycles of restimulation, peptide specific T cells were harvested and subgroups of which were determined with flow cytometry. Cytokines secreting profiles by CD4+ T cells and cytotoxicities of CD8+ T cells on tumor cells were assessed. The protective immunity by referred DCs tumor vaccines was also monitored.

RESULTSBoth Th and CTL epitopes primed DCs could elicit both CD4+ T cells and CD8+ T cells in vitro,of which CD4+ T cells released high amount of Th1 type cytokines (IFN-gamma, IL-2) on recognizing specific antigen, as well as CD8+ T cells exhibited efficient tumor-killing capacity. The effects induced by DCs pulsed with single epitope (Th or CTL epitope) in vivo were less effective than those induced by DCs pulsed with mixture epitopes.

CONCLUSIONSBoth Th and CTL epitopes augmented DCs tumor vaccine can induce CD4+ Th1 and CD8+ CTL mediated immune responses to eradicate gastric cancer cells.

Animals ; Cancer Vaccines ; immunology ; therapeutic use ; Cell Line ; Cell Line, Tumor ; Dendritic Cells ; immunology ; Epitopes, T-Lymphocyte ; immunology ; Immunotherapy ; Melanoma, Experimental ; Mice ; Peptides ; immunology ; Stomach Neoplasms ; therapy ; T-Lymphocytes, Cytotoxic ; immunology ; T-Lymphocytes, Helper-Inducer ; immunology

Human epidermal growth factor receptor 2 (HER2) proteins are overexpressed in a high proportion of gastric cancer (GC) cases and affect the maintenance of cancer stem cell (CSC) subpopulations, which are used as targets for the clinical treatment of patients with HER2-positive GC. Despite improvements in survival, numerous HER2-positive patients fail treatment with trastuzumab, highlighting the need for more effective therapies. In this study, we generated a novel type of genetically modified human T cells, expressing a chimeric antigen receptor (CAR), and targeting the GC cell antigen HER2, which harbors the CD137 and CD3ζ moieties. Our findings show that the expanded CAR-T cells, expressing an increased central memory phenotype, were activated by the specific recognition of HER2 antigens in an MHC-independent manner, and effectively killed patient-derived HER2-positive GC cells. In HER2-positive xenograft tumors, CAR-T cells exhibited considerably enhanced tumor inhibition ability, long-term survival, and homing to targets, compared with those of non-transduced T cells. The sphere-forming ability and in vivo tumorigenicity of patient-derived gastric cancer stem-like cells, expressing HER2 and the CD44 protein, were also inhibited. Our results support the future development and clinical application of this adoptive immunotherapy in patients with HER2-positive advanced GC.
Animals ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasms, Experimental ; immunology ; pathology ; therapy ; Receptor, ErbB-2 ; immunology ; Receptors, Antigen, T-Cell ; immunology ; Stomach Neoplasms ; immunology ; pathology ; therapy ; Tumor Cells, Cultured

antibody against tumor specific surface membrane protein was produced by immunizing a New Zealand White rabbit with antigen (66 kDa) prepared from the plasma membrane of rat hepatoma induced by feeding a diet containing 3'-methyl-4-dimethylaminoazobenzene, and was purified by protein A-Sepharose 6MB affinity chromatography. The purified antibody was incorporated into liposomes by a reverse phase evaporation vesicle method in order to prepare a tumor specific anticancer drug carrier. The effect of the antibody against tumor specific antigen was evaluated by comparing the inhibition of DNA synthesis in hepatoma cells with different preparations of methotrexate. Methotrexate encapsulated into liposome showed a stronger inhibitory effect on DNA synthesis (1.4-1.7 times) than free methotrexate. Liposomes having the antibody showed stronger inhibitory effect (3.1 times) on DNA synthesis than free methotrexate group in hepatic nodular area. From these results, it is concluded that tumor specific antibody inserted into liposomal membrane would be recognized by surface antigens which were expressed on the plasma surface membrane of rat hepatoma cells and thereby increase the carrying efficiency of drugs to the target cells. This could be useful in cancer chemotherapy.
Animal ; Antibodies, Neoplasm ; Antigens, Neoplasm/*immunology ; Antigens, Surface/*immunology ; Drug Carriers ; Liposomes ; Liver Neoplasms, Experimental/*drug therapy ; Male ; Methotrexate/*administration and dosage ; Rats ; Support, Non-U.S. Gov't

antibody against tumor specific surface membrane protein was produced by immunizing a New Zealand White rabbit with antigen (66 kDa) prepared from the plasma membrane of rat hepatoma induced by feeding a diet containing 3'-methyl-4-dimethylaminoazobenzene, and was purified by protein A-Sepharose 6MB affinity chromatography. The purified antibody was incorporated into liposomes by a reverse phase evaporation vesicle method in order to prepare a tumor specific anticancer drug carrier. The effect of the antibody against tumor specific antigen was evaluated by comparing the inhibition of DNA synthesis in hepatoma cells with different preparations of methotrexate. Methotrexate encapsulated into liposome showed a stronger inhibitory effect on DNA synthesis (1.4-1.7 times) than free methotrexate. Liposomes having the antibody showed stronger inhibitory effect (3.1 times) on DNA synthesis than free methotrexate group in hepatic nodular area. From these results, it is concluded that tumor specific antibody inserted into liposomal membrane would be recognized by surface antigens which were expressed on the plasma surface membrane of rat hepatoma cells and thereby increase the carrying efficiency of drugs to the target cells. This could be useful in cancer chemotherapy.
Animal ; Antibodies, Neoplasm ; Antigens, Neoplasm/*immunology ; Antigens, Surface/*immunology ; Drug Carriers ; Liposomes ; Liver Neoplasms, Experimental/*drug therapy ; Male ; Methotrexate/*administration and dosage ; Rats ; Support, Non-U.S. Gov't

OBJECTIVETo develop a new vaccine expressing membrane-bound heat shock protein 70 (mbHSP70) and further study its antitumor therapeutic effect.

METHODThe pre- established vector expressing mbHSP70 was transfected into CT26 cells of colorectal cancer. After the CT26 cells were incubated with 900 microg/ml G418, the sub-clones resistant to G418 were harvested and the HSP70 positive clones were selected by limiting dilution. The clones were amplified and inactivated, thereby the vaccine expressing mbHSP70 was prepared. Lymphocyte proliferation stimulated by the vaccines, NK and CTL activity was observed. The antitumor efficacy of vaccine was observed in BALB/c mice model with colorectal cancer.

RESULTSThe laser confocal microscopy and flow cytometry showed that there existed much HSP70 on the vaccine membrane surface. The HSP70 gene-modified vaccine displayed augmented lymphocyte proliferation and higher NK and CTL activity in vitro,and marked tumor suppression and prolonged survival time of the vaccinated micein vivo, when compared with its counterpart. Furthermore, mbHSP70-expression vaccine elicited lymphocyte proliferation most intensively, generated the highest NK and CTL activity as well as the strongest antitumor effect, and prolonged survival time of the vaccinated mice.

CONCLUSIONA new vaccine expressing mbHSP70 has more potent antitumor immunity and better therapeutic efficacy than HSP70 gene-modified vaccine did.

Animals ; Cancer Vaccines ; therapeutic use ; Cell Membrane ; immunology ; metabolism ; HSP70 Heat-Shock Proteins ; immunology ; Immunotherapy ; Mice ; Mice, Inbred BALB C ; Neoplasms, Experimental ; therapy ; Transfection

OBJECTIVETo develop a novel thermal treatment modality against metastatic tumor, and to verify the hypothesis that the extent of tumor angiogenesis damage and tumor cell necrosis, accompanied with immune suppression cells relief is deterministic to enhance therapeutic effect in the thermal treatment.

METHODSThe thermal treatment system was developed in our laboratory. The treatment including hyperthermia and alternate treatment, were locally applied to 4T1 murine mammary carcinoma. The extent of tumor necrosis was examined. Further investigations were performed to study the changes of MDSCs in peripheral blood and spleen.

RESULTSThe alternate treatment caused more damage to tumor microvasculature and tumor cell necrosis. Immunosuppression cells significantly reduced in peripheral blood and spleen. Moreover, it highly increased the survival rate of tumor-bearing mice.

CONCLUSIONSThe greatest destruction of primary tumor induced by the alternate treatment led to a relief of immune suppression in tumor bearing mice, and significantly increased therapeutic effect, especially for metastatic tumor.

Animals ; Female ; Hyperthermia, Induced ; methods ; Mammary Neoplasms, Experimental ; immunology ; pathology ; therapy ; Mice ; Mice, Inbred BALB C ; Myeloid Cells ; immunology ; Neoplasm Metastasis

BACKGROUNDDendritic cells (DCs) are the most powerful antigen-presenting cells to induce specific T-cell immunity, which plays an important role in the body's anti-tumor responses. In this study, we assessed the feasibility and efficacy of inducing T-cell immunity against Epstein-Barr virus (EBV)-associated tumors in vivo using dendritic cells transfected with EBV latent membrane 2A (LMP2A) recombinant adenovirus.

METHODSCytokine-activated bone marrow-derived DCs transfected with EBV LMP2A recombinant adenovirus were infused into BALB/c mice. Splenic cytotoxic T-cell responses were evaluated by cytotoxicity and interferon-gamma production assays. in vivo immune protection was then assessed in the mice tumor models implanted with tumor cells expressing EBV LMP2A.

RESULTSDCs transfected with EBV LMP2A recombinant adenovirus could strongly induce EBV LMP2A-specific cytotoxic T-cell responses and upregulate interferon-gamma production in vivo. Vaccination using these DCs led to prolongation of overall survival rates in the mice tumor models and retarded tumor growth.

CONCLUSIONSThe results suggest that DCs transfected with EBV LMP2A recombinant adenovirus can serve as a feasible and effective tool for eliciting LMP2A-specific cytotoxic T-cell responses against EBV LMP2A in vivo in the treatment of EBV-associated tumors.

Adenoviridae ; genetics ; Animals ; Dendritic Cells ; immunology ; Female ; Herpesvirus 4, Human ; immunology ; Immunotherapy ; Mice ; Mice, Inbred BALB C ; Neoplasms, Experimental ; therapy ; T-Lymphocytes, Cytotoxic ; immunology ; Transduction, Genetic ; Vaccination ; Viral Matrix Proteins ; immunology

OBJECTIVETo observe the inhibitory effect of dendritic cells (DCs) activated cytotoxicity T lymphocyte (CTL) combined with MAGE-1 nonapeptide on transplanted human hepatocyte carcinoma (HCC) in nude mice.

METHODSA model of HCC transplanted tumor was established by injecting BEL-7402 cell line HCC cells subcutaneously on the back of nude mice. Successful transplantation rate was 73%. Specific CTLs (1 x 10(6)), which were activated by DCs combined with MAGE-1 nonapeptide, were injected into the site of transplanted tumor (group A, n = 5). Another group of 17 mice were treated with same amounts of different kinds of cells, and they were divided into groups B, C, D, E, and F. The growth of tumor was observed, and pathological examination was also done.

RESULTS(1) The activated lymphocytes induced by DCs combined with MAGE-1 nonapeptide could suppress the growth of tumor and reduce the tumor size. In group A, 5/5 mice survived for at least two weeks, while the tumors grew rapidly and the majority of the mice died within two weeks in other groups (groups B, C, D, E, F) (P < 0.01). (2) Extensive necrosis and apoptosis were found in transplanted tumors in group A.

CONCLUSIONSThe DCs combined with MAGE-1 nonapeptide could not only inhibit the growth of HCC, but also result in produce death and apoptosis of HCC, hence preventing tumor metastasis and recurrence. The mechanism underlying tumor immunization resulted from DCs might be enhanced in apoptosis of tumor cells. MAGE-1 nonapeptide combined with DCs might be a potential novel tumor vaccine for the treatment of HCC.

Animals ; Antigens, Neoplasm ; Apoptosis ; Cancer Vaccines ; immunology ; Dendritic Cells ; immunology ; Humans ; Liver Neoplasms, Experimental ; immunology ; pathology ; therapy ; Melanoma-Specific Antigens ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Proteins ; administration & dosage ; genetics ; Neoplasm Transplantation ; T-Lymphocytes, Cytotoxic ; immunology ; Transplantation, Heterologous