g(m1)-ganglioside and Stomach-Neoplasms

Topics: Animals; Antibodies, Monoclonal; Antineoplastic Agents; Apoptosis; Benzodiazepines; Cell Proliferation; Drug Design; Female; G(M1) Ganglioside; GPI-Linked Proteins; Humans; Immunoconjugates; Lung Neoplasms; Mesothelin; Mice; Mice, SCID; Small Cell Lung Carcinoma; Stomach Neoplasms; Structure-Activity Relationship; Tetrahydroisoquinolines; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Cetuximab, a chimeric monoclonal antibody to epidermal growth factor receptor (EGFR), has been proved to have clinically significant antitumor activity against advanced colorectal cancers, but its therapeutic activity for gastric cancers remains unclear. In the present study, we investigated the antitumor effect and action mechanism of cetuximab using EGFR high-expressing (MKN-28) and EGFR low-expressing (GLM-1) gastric cancer cell lines without gene amplification. Cetuximab showed neither significant growth inhibition nor induction of apoptosis in either cell line in vitro, and only slightly inhibited ligand-induced phosphorylation of protein kinase B and extracellular signal-regulated kinase in MKN-28 cells. In contrast, cetuximab significantly inhibited subcutaneous and intraperitoneal tumor growth of MKN-28 cells, but not GLM-1 cells, in nude mice. This antitumor activity was significantly enhanced and diminished in nude mice by treatment with interleukin-2 (IL-2) and antiasialo GM1 antibody, which can expand and deplete natural killer (NK) cells, respectively. Antibody-dependent cellular cytotoxicity (ADCC) of cetuximab, as measured by (51)Cr release assay, was significantly higher in MKN-28 than in GLM-1 cells. This ADCC activity was enhanced by IL-2 and reduced by heat-aggregate of human immunoglobulin G, an inhibitor for FcR-III of NK cells. These results suggest that cetuximab in combination with IL-2 shows significant antitumor activity against EGFR high-expressing gastric cancer mainly through NK cell-mediated ADCC. Combination therapy with cetuximab and IL-2 would thus offer a new potential therapeutic approach for a subset of EGFR-overexpressing gastric cancers.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antibody-Dependent Cell Cytotoxicity; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cetuximab; Drug Synergism; ErbB Receptors; G(M1) Ganglioside; Humans; Immunohistochemistry; Interleukin-2; Male; Mice; Neoplasm Metastasis; Neoplasm Transplantation; Stomach Neoplasms; Transplantation, Heterologous

The biological significance of isolated tumor cells and micrometastasis in lymph node defined by the International Union against Cancer remains essentially unknown because of the lack of appropriate animal models. In the present study, we developed a lymph node micrometastasis model featuring a human gastric cancer cell line tagged with green fluorescent protein gene (GCIY-EGFP), which allows visualization of even isolated tumor cells in the development of metastasis without histologic procedure. Using this model, we investigated the effect of surgery and chemotherapy on the growth of early-phase metastasis formation in the lymph nodes.. The time course of spontaneous inguinal lymph node metastasis after s.c. inoculation of GCIY-EGFP cells into nude mice was examined with fluorescence dissecting microscopy. Then, the effects of surgical removal of the primary tumor with or without anti-asialo GM1 treatment or postoperative chemotherapy on the growth of isolated tumor cells and micrometastasis in the lymph nodes were examined.. GCIY-EGFP cells were found to metastasize spontaneously to the inguinal lymph nodes to form isolated tumor cells, micrometastasis, and, finally, develop macroscopic metastasis at 1 to 2, 3 to 5, and 5 weeks postinjection, respectively. When the primary tumors were removed within 2 weeks of inoculation, isolated tumor cells, but not micrometastasis, in the lymph nodes regressed by 4 weeks after surgery in all the mice examined (five of five). This spontaneous regression of isolated tumor cells was completely reversed by anti-asialo GM1 treatment, which could deplete natural killer cells effectively in nude mice. Chemotherapy following resection of the primary tumor at an early stage partially eliminated the remaining micrometastasis in the lymph nodes.. These results suggest that isolated tumor cells in the regional lymph nodes regressed by removal of the primary tumor mainly via natural killer cell-mediated antitumor activity and that micrometastasis in the lymph nodes could be effectively eliminated by the postoperative chemotherapy.

Topics: Animals; Antibodies, Monoclonal; G(M1) Ganglioside; Gastrectomy; Green Fluorescent Proteins; Humans; Killer Cells, Natural; Lymph Node Excision; Lymph Nodes; Lymphatic Metastasis; Male; Mice; Mice, Nude; Neoplasm Staging; Neoplasm Transplantation; Postoperative Care; Skin Neoplasms; Stomach Neoplasms; Tumor Cells, Cultured

Hypoxia-inducible factor 1 alpha (HIF-1alpha), a component of HIF-1, is expressed in human tumors and renders cells able to survive and grow under hypoxic (low-oxygen) conditions. YC-1, 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole, an agent developed for circulatory disorders that inhibits platelet aggregation and vascular contraction, inhibits HIF-1 activity in vitro. We tested whether YC-1 inhibits HIF-1 and tumor growth in vivo.. Hep3B hepatoma, NCI-H87 stomach carcinoma, Caki-1 renal carcinoma, SiHa cervical carcinoma, and SK-N-MC neuroblastoma cells were grown as xenografts in immunodeficient mice (69 mice total). After the tumors were 100-150 mm(3), mice received daily intraperitoneal injections of vehicle or YC-1 (30 microg/g) for 2 weeks. HIF-1 alpha protein levels and vascularity in tumors were assessed by immunohistochemistry, and the expression of HIF-1-inducible genes (vascular endothelial growth factor, aldolase, and enolase) was assessed by reverse transcription-polymerase chain reaction. All statistical tests were two-sided.. Compared with tumors from vehicle-treated mice, tumors from YC-1-treated mice were statistically significantly smaller (P<.01 for all comparisons), expressed lower levels of HIF-1 alpha (P<.01 for all comparisons), were less vascularized (P<.01 for all comparisons), and expressed lower levels of HIF-1-inducible genes, regardless of tumor type.. The inhibition of HIF-1 alpha activity in tumors from YC-1-treated mice is associated with blocked angiogenesis and an inhibition of tumor growth. YC-1 has the potential to become the first antiangiogenic anticancer agent to target HIF-1 alpha.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Carcinoma; Carcinoma, Hepatocellular; Cell Hypoxia; Culture Media, Conditioned; Endothelial Growth Factors; Enzyme-Linked Immunosorbent Assay; Female; G(M1) Ganglioside; Gene Expression Regulation, Neoplastic; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Immunoblotting; Indazoles; Intercellular Signaling Peptides and Proteins; Kidney Neoplasms; Killer Cells, Natural; Liver Neoplasms; Lymphokines; Male; Mice; Mice, SCID; Neoplasms; Neovascularization, Pathologic; Neuroblastoma; Platelet Endothelial Cell Adhesion Molecule-1; Precipitin Tests; Rats; Reverse Transcriptase Polymerase Chain Reaction; Stomach Neoplasms; Transcription Factors; Transplantation, Heterologous; Tumor Cells, Cultured; Uterine Cervical Neoplasms; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

We report a 63-year-old man who died of respiratory failure. He was well until 1992 (57 years of his age), when he had an onset of progressive weakness of the bilateral upper limbs. He showed no improvement with TRH administration in other hospital. On January 12, 1994, he admitted to our department because of the progressive muscle weakness. Neurologic examination revealed a muscular atrophy associated with severe weakness and hyporeflexia in both upper limbs, and fasciculation were seen in his tongue. Electrophysiological studies revealed mild conduction block in the left medial nerve, and F-waves were not evoked in the left ulnar nerve and bilateral median nerves. After an administration of 25 g/day of human gamma-immunoglobulin for 5 days, conduction block as well as F-wave abnormalities in the left median and left ulnar nerve were improved, yet no improvement of muscle weakness was seen. The anti-GM1 IgG titer was transiently elevated in the patient's serum after gamma-immunoglobulin therapy. On September 8, 1994, subtotal gastrectomy was performed because of the early stage gastric cancer. Histological examination showed poorly differentiated adenocarcinoma (signet-ring cell carcinoma). His muscle weakness had been gradually extended to the lower limbs and he couldn't walk himself on January, 1998. On March, 1998, he developed tetraplegia, mild dysphagia, dysuria and the respiratory disturbance. On April 12, 1998, he admitted to our department for the second time. Neurologic examination revealed a muscular atrophy and fasciculation associated with severe weakness in all of his limbs, tongue and musclus masseter. Neither deep tendon reflex nor pathologic reflex was evoked in his upper and lower extremities. His ocular movements and sensations were well preserved. He died of respiratory failure on May 1, 1998. The patient was presented in a neurological CPC. Neurological and laboratory findings suggested a spinal progressive muscular atrophy (SPMA). However, there were several unusual points as a typical SPMA in this case, that is, an improvement of the electrophysiological abnormalities by gamma-globulin treatment, as well as transient elevation of anti-GM1 antibody. The clinical neurologists have arrived at the conclusion that the patient had lower motor neuron syndrome associated with anti-ganglioside antibody and cause of death was ascribed to the respiratory failure. We discussed whether this case was SPMA or multifocal motor neuropathy. Postmort

Topics: Autoantibodies; Carcinoma, Signet Ring Cell; Diagnosis, Differential; Diverticulum, Colon; G(M1) Ganglioside; gamma-Globulins; Humans; Male; Middle Aged; Motor Neuron Disease; Muscular Atrophy, Spinal; Stomach Neoplasms; Thyroiditis

Gangliosides of human gastric and mammary tumours and of homologous normal tissues were studied by using biochemical methods and specific antisera. It was found that in most cases GM3, GD3 and GM1 are predominant gangliosides, whereas several polar components are minor ones. A comparison of the relative amount of ganglioside fractions revealed that in gastric tumours the per cent content of polar compounds is higher than in intact tissue; however, the absolute content of all gangliosides is markedly increased. A comparative study of the composition of mammary tumour and normal tissue gangliosides demonstrated two types of changes: i) the absolute content of all gangliosides in tumour tissue was increased and, ii) the increase in the content of total gangliosides was paralleled with the appearance of a new fraction (presumably GM4), the decrease of the GD3 content and the disappearance of polar gangliosides. A possible mechanism of this effect is discussed.

Topics: Breast Neoplasms; G(M1) Ganglioside; G(M3) Ganglioside; Gangliosides; Humans; Stomach Neoplasms

Culture of tumor-infiltrating lymphocytes (TIL) containing about 20% BMC2 tumor cells with recombinant human interleukin 2 (rIL-2) resulted in the diminish of tumor cells and the growth of lymphocytes. These IL-2-activated lymphocytes showed a strong cytotoxic activity against not only syngeneic tumor cells but also allogeneic tumor cells. Such broad-reactive killer cells, termed lymphokine-activated killer (LAK) cells, are also inducible from spleen cells by in vitro activation with IL-2. However, LAK cells generated from TIL (TIL-LAK) showed higher cytotoxic activity against BMC2 than LAK cells generated from spleen cells (S-LAK). Furthermore, it was demonstrated that TIL-LAK cells revealed marginal cytotoxic activity against normal Con A blasts and YAC-1 cells as opposed to S-LAK. Flow cytometric analysis of TIL-LAK indicated that TIL-LAK cells mainly consisted of Thy 1.2+, Ly 2+, asialo GM1+ cells. TIL-LAK cells displayed not only in vitro cytotoxicity but also in vivo anti-tumor activity. Furthermore, it was also confirmed that TIL-LAK cells could be induced in autochthonous mouse tumor systems and human gastric tumor systems.

Topics: Animals; Antigens, Ly; Antigens, Surface; Cytotoxicity, Immunologic; G(M1) Ganglioside; Glycosphingolipids; Immunity, Cellular; Interleukin-2; Killer Cells, Natural; Male; Mice; Mice, Inbred Strains; Neoplasm Transplantation; Neoplasms, Experimental; Recombinant Proteins; Stomach Neoplasms; Thy-1 Antigens

Influences of natural killer cells on the transplantable human tumors was evaluated by using anti-asialo GM1 antibody. Two human gastric adenocarcinomas designated as St-4 (poorly differentiated) and St-40 (well differentiated) were inoculated into nude mice. The effects of anti-asialo GM1 antibody were assessed in terms of tumor doubling time (Td) and 3H-thymidine (3H-TdR) uptake labeling index (L.I.). Whereas the Td of St-4 was significantly shortened by administration of anti-asialo GM1 antibody, no noticeable changes were observed in St-40. This enhanced growth of St-4 was also supported by the elevation of L.I. both in flashing and repeating methods. On the other hand, as the repeated L.I. of St-40 was almost 100% in control tumors, repeated L.I. was not increased by the administration of anti-asialo GM1 antibody. It was supported that natural killer activity of nude mice regulated the growth of transplantable human tumors concerning with the growth fractions.

Topics: Adenocarcinoma; Animals; Antibodies; G(M1) Ganglioside; Glycosphingolipids; Humans; Killer Cells, Natural; Mice; Mice, Nude; Neoplasm Transplantation; Stomach Neoplasms; Transplantation, Heterologous

Intravenous injection of anti-asialo GM1, which has been shown to eliminate natural killer (NK) activity in vitro in the presence of complement, completely abolished NK activity against lymphoma cell line (YAC-1) in spleen cells from athymic nude mice as well as from conventional mice. An immunofluorescence study revealed a decreased number of asialo GM1 positive cells in the spleens of mice injected with anti-asialo GM1 than in those of mice injected with normal rabbit serum. In the nude mice with reduced NK activity, incidence of tumor take and the growth were enhanced when syngeneic (RL male-1), and allogeneic (YAC-1) tumors and human tumors were transplanted subcutaneously. These results strongly suggest that NK cells play an important role in transplanted-tumor growth in vivo.

Topics: Animals; Antibodies; Cell Transformation, Neoplastic; Dose-Response Relationship, Immunologic; Female; G(M1) Ganglioside; Gangliosides; Humans; Inguinal Canal; Killer Cells, Natural; Lymph Nodes; Lymphoma; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Metastasis; Neoplasm Transplantation; Rabbits; Stomach Neoplasms