title: An anti-GD2 monoclonal antibody enhances apoptotic effects of anti-cancer drugs against small cell lung cancer cells via JNK (c-Jun terminal kinase) activation.
abstract: Small cell lung cancer (SCLC) cell lines specifically express ganglioside GD2, and anti-GD2 monoclonal antibodies (mAbs) caused suppression of cell growth and induced apoptosis of SCLC cells with single use. Here, enhancement of the cytotoxic effects of various anti-cancer drugs with an anti-GD2 mAb was demonstrated. The cytotoxicity of all six drugs examined was markedly enhanced, i.e. 2.4 - 7.8-fold increase of cell sensitivity in terms of IC(50). In particular, the combination of cisplatin (CDDP) with an anti-GD2 mAb resulted in prominent enhancement of cytotoxicity even in low - moderate GD2-expressing lines. The anti-GD2 mAb induced weak activation of c-Jun terminal kinase (JNK) in SCLC cells, and all anti-cancer drugs also induced its activation to various degrees. When CDDP and an anti-GD2 mAb were used together, significantly stronger JNK activation was observed corresponding to the cytotoxic effects, suggesting that synergistic phosphorylation of JNK with two reagents induced prominent apoptosis. The essential role of JNK in the induction of SCLC apoptosis with CDDP and anti-GD2 mAb was confirmed by experiments with a JNK inhibitor, curcumin. These results suggest that anti-GD2 mAbs would be very efficient in combination with anti-cancer drugs, both to achieve SCLC-specific cytotoxicity and to enhance its magnitude.
authors.affiliation: Department of Biochemistry II, Nagoya University School of Medicine, Showa-ku, Nagoya 466-0065, Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Yoshida
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Kawaguchi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sato
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Ueda
authors.forename: Koichi
authors.initials: K
authors.lastname: Furukawa
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D017209:Apoptosis; D018288:Carcinoma, Small Cell / Q000188:drug therapy* / Q000473:pathology; D002945:Cisplatin / Q000494:pharmacology; D004396:Coloring Agents / Q000494:pharmacology; D053938:DNA Fragmentation; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004789:Enzyme Activation; D005434:Flow Cytometry; D005732:Gangliosides / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D020287:In Situ Nick-End Labeling; D020128:Inhibitory Concentration 50; D048031:JNK Mitogen-Activated Protein Kinases; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D013997:Time Factors; D014407:Tumor Cells, Cultured
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D004396:Coloring Agents; D005732:Gangliosides; D013778:Tetrazolium Salts; D013844:Thiazoles; C019403:ganglioside, GD2; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; C022616:thiazolyl blue; D002945:Cisplatin