Inhibitory effect of glycyrrhizin on experimental pulmonary metastasis in mice inoculated with B16 melanoma.
The pulmonary metastasis of B16 melanoma cells has been shown to be influenced by tumor-associated T helper type 2 cells (Th2 cells). Glycyrrhizin (GR), an active component of licorice roots, has been described as an inducer of CD4+ CD28+ TCR alpha/beta+ T cells, which are capable of counteracting Th2 cytokine production by Th2 cells. In the present study, the anti-metastatic effect of GR in mice implanted with highly metastatic B16F10 melanoma cells was investigated. When mice inoculated with B16F10 melanoma cells (1 x 10(5) cells/mouse, i.v.) were treated with GR (10 mg/kg) 1, 3, 5 and 7 days after the tumor inoculation, the incidence of metastases decreased on average; 48 colonies were found in the GR-treated group and 208 in the saline-treated group. Similarly, 84% of metastases were inhibited in these mice after they were inoculated with splenic CD4+ T cells from mice treated with GR (GR-CD4+ T cells). These results suggest that GR inhibits the pulmonary metastases of B16 melanoma through the regulation of tumor-associated Th2 cells.
Kobayashi
Makiko
M
Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas 77555, USA.
Fujita
Kazuhiko
K
Katakura
Tatsushi
T
Utsunomiya
Tokuichiro
T
Pollard
Richard B
RB
Suzuki
Fujio
F
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D019695:Glycyrrhizic Acid / Q000494:pharmacology*; D015847:Interleukin-4 / Q000096:biosynthesis; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000556:secondary*; D008546:Melanoma, Experimental / Q000188:drug therapy* / Q000276:immunology / Q000556:secondary*; D051379:Mice; D009368:Neoplasm Transplantation; D018418:Th2 Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D014407:Tumor Cells, Cultured
D000972:Antineoplastic Agents, Phytogenic; D015847:Interleukin-4; D019695:Glycyrrhizic Acid