Antitumor activity of oenothein B, a unique macrocyclic ellagitannin.
The antitumor effect of oenothein B, a macrocyclic ellagitannin from Oenothera erythrosepala Bordas, on rodent tumors was studied. Oenothein B exhibited a strong antitumor activity against MM2 ascites tumors upon intraperitoneal administration to the mice before or after the tumor inoculation. The tannin also inhibited the growth of Meth-A solid type tumor in mice. This antitumor effect of the tannin could not be attributed to its direct cytotoxic action on tumor cells, because the cytotoxicity was very weak in the presence of serum protein. When oenothein B was injected into the peritoneal cavity of mice, peritoneal exudate cells, including cytostatic macrophages, were induced. Furthermore, in the in vitro treatment of macrophages from mice and humans, the tannin stimulated release of an interleukin 1 (IL-1)-like activity and IL-1 beta from the cells. These results suggest that oenothein B exerts its antitumor effect through potentiation of the host-immune defense via activation of macrophages.
Miyamoto
K
K
Research Laboratory for Development of Medicine, Hokuriku University, School of Pharmacy, Kanazawa.
Nomura
M
M
Sasakura
M
M
Matsui
E
E
Koshiura
R
R
Murayama
T
T
Furukawa
T
T
Hatano
T
T
Yoshida
T
T
Okuda
T
T
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D002470:Cell Survival / Q000187:drug effects; D005260:Female; D005354:Fibrosarcoma / Q000188:drug therapy*; D047348:Hydrolyzable Tannins; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D010844:Picibanil / Q000494:pharmacology / Q000627:therapeutic use; D012513:Sarcoma, Experimental / Q000188:drug therapy; D013634:Tannins / Q000494:pharmacology / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured
D000972:Antineoplastic Agents, Phytogenic; D047348:Hydrolyzable Tannins; D013634:Tannins; C080077:oenothein B; D010844:Picibanil