Inhibitory effect of antibodies against human chorionic gonadotropin on the growth of colorectal tumour cells.

Human chorionic gonadotropin (hCG) was initially believed to be secreted exclusively by the embryo with its primary function being “rescue” of the corpus luteum. However, recently it has been found that the hormone (or its individual subunits) is also secreted by many cancers and that in many cases secretion is associated with poor patient prognosis. In this study, we assessed the presence of hCG in colorectal cancer cells (CCL-253) and evaluated the anti-tumour effects of anti-hCG antibodies in vitro and in vivo. Anti-hCG antibodies were reactive with CCL-253, as revealed by confocal immunoflourescence microscopy; both cell surface and intracellular expression were observed. Western blot analysis showed that antibodies appeared to interact with several moieties, indicating a level of cross-reactivity. Anti-hCG antiserum specifically reduced the viability of tumor cells and the addition of complement increased in vitro anti-tumor effects. In nude mice implanted with CCL-253 cells, administration of anti-hCG antiserum caused a significant reduction in tumor volume; all treated animals survived, while mortality was observed in control animals. Results suggest that anti-hCG antibodies can mediate significant anti-tumor activity both in vitro and in vivo and lend support to the rationale of anti-hCG immunization in the therapy of gonadotropin- sensitive cancers.

The Anti-tumor Effect of Adoptive Immunotherapy with Dendritic Cells Cultured from the Bone Marrow in a Murine Squamous Cell Carcinoma Model / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: It is known that patients with malignant tumor often have depressed antitumor immunity. Much information has been generated about a biologically-based therapy, which can induce or activate antitumor cytotoxic T lymphocytes (CTL) capable of recognizing the antigens associated with the major histocompatibility complex molecules (MHC). Optimal induction of CTL seems to require contact with antigenic peptides presented by antigen presenting cell (APC). Dendritic cells (DC) are currently considered to be the most effective and professional APC. MATERIALS AND METHODS: With an injection of SCC cells (1x105) to the back of C3H mouse, a consistent and immunocompetent experimental animal tumor model was achieved. DCs were successfully cultured from the bone marrow of C3H mouse, and phenotypically they expressed high levels of co-stimulatory molecules and abundant MHC. Cultured DCs were intraperitoneally injected into the tumor-established mouse. RESULTS: In the treated group, tumor sizes were smaller, infiltration to the adjacent structures were limited. T cells extracted from the spleen of the treated group showed better proliferative and cytolytic activity toward tumor cells. The results of this study suggest that DCs have an effect to suppress the growth of tumors and to induce higher T cell reactivity toward tumor cells. CONCLUSION: These results may help in proceeding further immunologic approaches to reduce the morbidity and mortality in patients with the head and neck SCC.

Enhancing effect of tumor necrosis factor (TNF) on the in vitro and in vivo antitumor activity of LAK cells / 中国免疫学杂志

Although TNF alone was not capable of inducing LAK activity and could not enhance the LAK activity induced by IL-2 at optimal concentration (1000U/ml), TNF (500U/ml) was found to act synergistically with IL-2 at suboptimal concentration (10～100U/ml). This TNF/IL-2 synergistic effect was blocked by anti-TNF McAb (Z8) or anti-IL-2R? chain McAb (TU27). When TNF and IL-2/LAK cells were combined to treat tumor-bearing mice,TNF could potentiate significantly the therapeutic effect of IL-2/LAK cells in vivo.