title: MDP-Lys(L18), a lipophilic derivative of muramyl dipeptide, inhibits the metastasis of haematogenous and non-haematogenous tumours in mice.
abstract: The antimetastatic effects of MDP-Lys(L18), a lipophilic derivative of muramyl dipeptide (MDP), against three different types of highly metastatic murine tumour cells, B16-BL6 melanoma, colon 26-M3.1 carcinoma and L5178Y-ML25 T lymphoma, were examined in C57BL/6, Balb/c and CDF1 mice, respectively. The administration of 100 micrograms of MDP-Lys(L18) 2 or 4 days before tumour inoculation led to a significant decrease in lung metastasis of B16-BL6 melanoma or colon 26-M3.1 carcinoma cells. MDP-Lys(L18) was also effective in the inhibition of liver metastasis of L5178Y-ML25 lymphoma cells by administration 2 or 4 days before tumour inoculation. The prophylactic effect of 100 micrograms of MDP-Lys(L18) on tumour metastasis was evident for the different administration routes, i.e. subcutaneous, intravenous or intranasal injection, or oral administration. It is of prime interest that oral administration of 1 mg of MDP-Lys(L18) induced a significant decrease in lung metastasis of B16-BL6 melanoma cells. Administration of MDP-Lys(L18) 4 days before assay led to induction of tumoricidal activity by peritoneal macrophages and growth inhibition by the sera against B16-BL6 or L929 cells. When MDP-Lys(L18) was subcutaneously administered five times after tumour inoculation to test therapeutic effect in an experimental and spontaneous metastasis model using B16-BL6 melanoma, the consecutive administrations of MDP-Lys(L18) significantly inhibited lung metastasis in tumour-bearing mice. These results suggest that MDP-Lys(L18) is able to enhance host resistance to reduce tumour metastasis and is a potent immunomodulating agent which may be applied prophylactically or therapeutically for the treatment of cancer metastasis.
authors.affiliation: Institute of Immunological Science, Hokkaido University, Sapporo, Japan.
authors.forename: Y C
authors.initials: YC
authors.lastname: Yoo
authors.forename: I
authors.initials: I
authors.lastname: Saiki
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: I
authors.initials: I
authors.lastname: Azuma
mesh_terms: D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D005260:Female; D007167:Immunotherapy; D007940:Leukemia L5178 / Q000276:immunology / Q000628:therapy; D008114:Liver Neoplasms, Experimental / Q000517:prevention & control / Q000556:secondary; D008175:Lung Neoplasms / Q000517:prevention & control / Q000556:secondary; D008262:Macrophage Activation; D017737:Macrophages, Peritoneal / Q000276:immunology; D008546:Melanoma, Experimental / Q000276:immunology / Q000556:secondary / Q000628:therapy; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000276:immunology / Q000556:secondary / Q000628:therapy*; D009360:Neoplastic Cells, Circulating; D013160:Splenic Neoplasms / Q000517:prevention & control / Q000556:secondary
chemical_list: D000276:Adjuvants, Immunologic; D000119:Acetylmuramyl-Alanyl-Isoglutamine; C036866:romurtide