lipid-a and Carcinoma--Hepatocellular

We previously found that artificial glycosphingolipids (artGSLs) containing very-long-chain fatty acids behave as strong immunogens in mice and promote the production of antibodies recognizing the oligosaccharide portion of artGSLs as the epitope. Here, we report that the oligosaccharide structure of artGSLs influences these immunogenic properties. We evaluated the antibody-inducing activity of artGSLs with different oligosaccharide structures in mice and found strong IgG-inducing activity only with an artGSL containing a core-fucosylated tetraoligosaccharide (Manβ1,4GlcNAcβ1,4[Fucα1,6]GlcNAc). To characterize the immunogenic properties of this artGSL, we analyzed various derivatives and found that the non-reducing terminal mannose structure was critical for the antibody-inducing activity. These artGSLs also exhibited IgG-inducing activity dependent on co-administration of lipid A adjuvant, but no cytokine-inducing activity similar to α-galactosylceramide was detected. Furthermore, repetitive immunization with the artGSL promoted the production of antibodies against a core-fucosylated α-fetoprotein isoform (AFP-L3) known as a hepatocellular carcinoma-specific antigen. These results indicate that the newly designed artGSLs specifically induce adaptive immune responses and promote antibody production by B cells, which can be utilized to develop anti-glycoconjugate antibodies and cancer vaccines targeting tumor-associated carbohydrate antigens.

Topics: Adjuvants, Immunologic; alpha-Fetoproteins; Animals; Carcinoma, Hepatocellular; Glycosphingolipids; Immunity, Humoral; Immunization; Lipid A; Liver Neoplasms; Mice

We have reported that ONO-4007, a novel synthetic lipid A derivative with low toxic activities, produced large amount of tumor necrosis factor (TNF)-alpha selectively in the tumor tissues and brought about complete cures in about 60% of rats bearing TNF-alpha sensitive KDH-8 cells, which also secreted a large amount of transforming growth factor (TGF)-beta. In our present study, to explore ONO-4007 induced Th1-type immune response, we investigated the mRNA expression of interferon (IFN)-gamma, Interleukin (IL)-1beta, IL-6, IL-10, IL-12 in KDH-8 bearing rats. We next examined the nitric oxide (NO) production. We found that IFN-gamma, IL-1beta, IL-6 and IL-12 mRNA expression of the tumor tissue were higher in the ONO-4007 treated rats than in phosphate buffer saline (PBS) treated rats. Western blotting also revealed that IL-12 protein production was increased. NO production from peritoneal macrophages were suppressed in tumor-bearing rats, but ONO-4007 restored it up to the normal level. These results suggest that ONO-4007 induces and restores Th1-type immune response through cytokine production cascade, followed by initial TNF-alpha production, eventually leading to tumor eradication.

Topics: Animals; Carcinoma, Hepatocellular; Female; Interferon-gamma; Interleukin-1; Interleukin-10; Interleukin-12; Interleukin-6; Lipid A; Liver Neoplasms, Experimental; Macrophages, Peritoneal; Nitric Oxide; Rats; Rats, Wistar; RNA, Messenger; RNA, Neoplasm; Th1 Cells; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

ONO-4007 is a new synthetic lipid A derivative with low endotoxic activities. We have examined the therapeutic effects of ONO-4007 on rat hepatocellular carcinoma KDH-8 cells, rat fibrosarcoma KMT-17 cells and rat mammary adenocarcinoma SST-2 cells in vivo. Multiple systemic i.v. administration of ONO-4007 was performed on days 7, 14 and 21 after tumor implantation of KDH-8 and SST-2 cells, and on days 5, 10 and 15 after tumor implantation of KMT-17 cells. ONO-4007 showed significant therapeutic effects on KDH-8 cells; by the administration of ONO-4007 (2.5 mg/kg) 70% of rats were cured and by the administration of ONO-4007 (5 mg/kg) 50% of rats were cured. Furthermore, the ONO-4007 treatment prolonged the mean survival time of KDH-8-bearing rats. However, ONO-4007 had no effect on KMT-17 and SST-2 cells, and it had no direct effect on the growth of KDH-8 cells in vivo. Albeit the stimulation with ONO-4007 induced mRNA expressions of interleukin (IL)-1alpha, IL-6 and tumor necrosis factor (TNF)-a, those of IL-2, IL-4, IL-10 and interferon (IFN)-gamma were not induced. Using a bioassay, we found that the production of TNF-alpha in the tumor tissues was induced by ONO-4007 in a dose-dependent manner. KDH-8 cells were sensitive to human natural TNF-alpha in vitro. However, KMT-17 and SST-2 cells were resistant against TNF-alpha in vitro. These results suggest that ONO-4007 is therapeutically useful for the treatment of TNF-alpha-sensitive tumors.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Survival; Cytokines; Female; Fibrosarcoma; Indicators and Reagents; Lipid A; Liver Neoplasms; Mammary Neoplasms, Experimental; Neoplasm Transplantation; Polymerase Chain Reaction; Rats; Rats, Wistar; RNA, Neoplasm; Spleen; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha