ovalbumin and Carcinoma--Hepatocellular

Topics: Aged; Animals; Base Sequence; Carcinoma, Hepatocellular; Cell Nucleus; Cytoplasm; Humans; Kinetics; Liver; Liver Neoplasms; Models, Biological; Neoplasms, Experimental; Ovalbumin; Oxidation-Reduction; Polyribosomes; Protein Biosynthesis; Rats; RNA, Messenger; S-Adenosylhomocysteine; S-Adenosylmethionine

Seleno-ovalbumin (Se-OVA) was a selenium conjugating protein synthesized by the combination of ovalbumin (OVA) and inorganic selenium. In this paper, the structure of Se-OVA was characterized, and the anticancer effect of Se-OVA on hepatocellular carcinoma HepG2 cells was investigated. Through FT-IR, UV, endogenous fluorescence and XRD assays, it was found that the structural characterization of Se-OVA changed after seleno-modification. In addition, the cell assays showed that Se-OVA could induce apoptosis of HepG2 cells by arresting cell cycle in S phase, generating intracellular reactive oxygen species, reducing the mitochondrial transmembrane potential, and triggering the Bax- and Bcl-2-mediated mitochondria apoptosis pathway. These findings revealed that Se-OVA might serve as a novel anticancer drug for cancer adjuvant therapy.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Hepatocellular; Cell Cycle; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Hep G2 Cells; Humans; Liver Neoplasms; Membrane Potential, Mitochondrial; Mitochondria; Organoselenium Compounds; Ovalbumin; Reactive Oxygen Species; Signal Transduction; Spectroscopy, Fourier Transform Infrared

Immunostimulatory monoclonal antibodies (ISmAb) that unleash antitumor immune responses are showing efficacy in cancer clinical trials. Anti-B7-H1 (PD-L1) monoclonal antibodies (mAb) block a critical inhibitory pathway in T cells, whereas anti-CD137 and OX40 mAbs provide T-cell costimulation. A combination of these ISmAbs (anti-CD137 + anti-OX40 + anti-B7-H1) was tested using a transgenic mouse model of multifocal and rapidly progressing hepatocellular carcinoma, in which c-myc drives transformation and cytosolic ovalbumin (OVA) is expressed in tumor cells as a model antigen.. Flow-cytometry and immunohistochemistry were used to quantify tumor-infiltrating lymphocytes (TIL) elicited by treatment and assess their activation status and cytolytic potential. Tolerance induction and its prevention/reversal by treatment with the combination of ISmAbs were revealed by in vivo killing assays.. The triple combination of ISmAbs extended survival of mice bearing hepatocellular carcinomas in a CD8-dependent fashion and synergized with adoptive T-cell therapy using activated OVA-specific TCR-transgenic OT-1 and OT-2 lymphocytes. Mice undergoing therapy showed clear increases in tumor infiltration by activated and blastic CD8(+) and CD4(+) T lymphocytes containing perforin/granzyme B and expressing the ISmAb-targeted receptors on their surface. The triple combination of ISmAbs did not result in enhanced OVA-specific cytotoxic T lymphocyte (CTL) activity but other antigens expressed by cell lines derived from such hepatocellular carcinomas were recognized by endogenous TILs. Adoptively transferred OVA-specific OT-1 lymphocytes into tumor-bearing mice were rendered tolerant, unless given the triple mAb therapy.. Extension of survival and dense T-cell infiltrates emphasize the translational potential of combinational immunotherapy strategies for hepatocellular carcinoma. Clin Cancer Res; 19(22); 6151-62. ©2013 AACR.

Topics: Adoptive Transfer; Animals; Antibodies, Monoclonal; B7-H1 Antigen; Carcinoma, Hepatocellular; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Cytotoxicity, Immunologic; Disease Models, Animal; Immunotherapy; Liver Neoplasms; Lymphocyte Activation; Lymphocyte Count; Lymphocytes, Tumor-Infiltrating; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Mice, Transgenic; Ovalbumin; OX40 Ligand; Survival; T-Lymphocytes, Cytotoxic; Tumor Necrosis Factor Receptor Superfamily, Member 9; Tumor Necrosis Factors

Virotherapy can potentially be used to induce tumor-specific immune responses and to overcome tumor-mediated tolerance mechanisms because apoptotic tumor cells are exposed together with viral danger signals during oncolysis. However, insufficient numbers of dendritic cells (DC) present at the site of oncolysis can limit a tumor-specific immune response and the resulting therapeutic benefit. We investigated MHC class I peptide-specific immune responses against model antigens ovalbumin (OVA) and hemagglutinin (HA) in mouse tumor models that support efficient replication of the oncolytic adenovirus hTert-Ad. Virotherapy resulted in peptide-specific cytotoxic T-cell responses against intracellular tumor antigens. Triggering of DC and T-cell infiltration to the oncolytic tumors by macrophage inflammatory protein 1alpha (MIP-1alpha, CCL3) and Fms-like tyrosine kinase-3 ligand (Flt3L) enhanced both antitumoral and antiviral immune responses. Although immune-mediated clearance of the virus can restrict therapeutic efficacy of virotherapy, MIP-1alpha/FLT3L-augmented hTert-Ad virotherapy inhibited local tumor growth more effectively than virotherapy alone. In agreement with the hypothesis that immune-mediated mechanisms account for improved outcome in MIP-1alpha/FLT3L virotherapy, we observed systemic antitumoral effects by MIP-1alpha/FLT3L virotherapy on uninfected lung metastasis in immunocompetent mice but not in nude mice. Furthermore, MIP-1alpha/FLT3L virotherapy of primary tumors was strongly synergistic with tumor DC vaccination in inhibition of established lung metastasis. Combined viroimmunotherapy resulted in long-term survival of 50% of treated animals. In summary, improvement of cross-presentation of tumor antigens by triggering of DC and T-cell infiltration during virotherapy enhances antitumoral immune response that facilitates an effective viroimmunotherapy of primary tumors and established metastases.

Topics: Adenoviridae; Animals; Antineoplastic Agents; Antiviral Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Dendritic Cells; Disease Models, Animal; Female; Hemagglutinins; Kidney; Male; Mice; Mice, Inbred C57BL; Mice, Nude; Neoplasms; Ovalbumin; Telomerase

The chicken ovalbumin upstream-promoter transcription factor (COUP-TF) has a dual effect on the regulation of the mitochondrial 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase gene. COUP-TF could act as a transcriptional activator or repressor of this gene through different DNA sequences. COUP-TF induces expression of a reporter gene linked to the mitochondrial HMG-CoA synthase gene promoter in human hepatoma HepG2 cells, but represses it in a Leydig tumour cell line (R2C); in both these cell lines the expression of the mitochondrial HMG-CoA synthase gene mimics that of liver and testis. The activation is promoted by a fragment of the gene from coordinates -62 to +28, which contains a GC box and a TATA box, and where no COUP-TF binding site was observed by in vitro DNA binding studies. On the other hand, the COUP-TF inhibitory effect is mainly due to repression of peroxisome-proliferator-activated receptor-dependent activation of the gene, interacting with the region from -104 to -92. To our knowledge this work represents the second example of a target gene for COUP-TF I that could be either activated or repressed by the action of this receptor through different DNA sequences of the same gene.

Topics: Animals; Carcinoma, Hepatocellular; Chickens; COUP Transcription Factor I; DNA; DNA-Binding Proteins; Enzyme Repression; Gene Expression Regulation, Enzymologic; Humans; Hydroxymethylglutaryl-CoA Synthase; Leydig Cell Tumor; Microbodies; Mitochondria; Ovalbumin; Rats; Receptors, Cytoplasmic and Nuclear; Trans-Activators; Transcription Factors; Tumor Cells, Cultured

Topics: Animals; Carcinoma, Hepatocellular; Cytotoxicity Tests, Immunologic; Guinea Pigs; Immune Sera; Immunity, Cellular; Liver Neoplasms; Lymphocytes; Lymphotoxin-alpha; Mast-Cell Sarcoma; Mice; Ovalbumin; Rabbits; Spleen

Synthesis of ovalbumin in fragmented oviduct magnum explants of immature, estrogen-stimulated chicks has been studied in the presence of exogenous tRNA. tRAN from Novikoff hepatoma specifically inhibited ovalbumin synthesis, determined by precipitation with antisera. In addition, the major protein(s) synthesized in the presence of hepatoma tRNA had higher electrophoretic mobility than ovalbumin, as shown by sodium dodecyl sulfate polyacrylamide gel electrophoresis. tRNAs from rat liver, rooster liver, and hen oviduct did not affect ovalbumin synthesis, although oviduct tRNA is stimulatory during the earlier stages of estrogen stimulation.

Topics: Animals; Carcinoma, Hepatocellular; Chickens; Dactinomycin; Estradiol; Female; Liver; Liver Neoplasms; Male; Neoplasms, Experimental; Ovalbumin; Oviducts; Rats; Ribonucleases; RNA, Transfer