Identification of a novel growth-promoting factor with a wide target cell spectrum from various tumor cells as catalase.
We have previously reported the purification from human erythrocyte extracts of a novel growth-promoting factor with a wide target cell spectrum. The factor has been identified as catalase. As cell extracts from a variety of tumor cell types exhibited both growth-promoting and catalase activities, the relationship between the two activities was examined using cell extracts from three different cell types, human myeloid cells (U937), human melanoma cells (A375-C6), and human B cells (Daudi). The growth-promoting and catalase activities were well correlated in these cell extracts. The antibody against human catalase absorbed not only catalase activity, but also the growth-promoting activity of extracts from these cell types. Treatment of the cell extracts from these cells with an irreversible catalase inhibitor, aminotriazole, abolished both the catalase and growth-promoting activities. In contrast, glutathione peroxidase (GSH-Px) activity was neither absorbed with the anti-catalase antibody, nor inhibited by aminotriazole. In addition, GSH-Px exhibited growth-promoting activity only in the presence of glutathione (GSH). These results, in conjunction with the effect of aminotriazole on the growth-promoting activity of catalase, suggest that catalase is the major growth-promoting molecule in the cell extracts, and H2O2-decomposing activity is important. Northern blot analysis revealed that these cells contained authentic catalase mRNA, and the mRNA level was compatible with the catalase and growth-promoting activities in the cell extracts. These results suggest that the growth-promoting activity in the tumor cell extracts is due to catalase.
Miyamoto
T
T
Department of Hygienic Chemistry, Faculty of Pharmaceutical Sciences, Nagoya City University.
Hayashi
M
M
Takeuchi
A
A
Okamoto
T
T
Kawashima
S
S
Takii
T
T
Hayashi
H
H
Onozaki
K
K
D000640:Amitrole / Q000494:pharmacology; D000906:Antibodies / Q000737:chemistry; D015153:Blotting, Western; D002374:Catalase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D002457:Cell Extracts / Q000737:chemistry; D005979:Glutathione Peroxidase / Q000378:metabolism; D006133:Growth Substances / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000378:metabolism
D000906:Antibodies; D002457:Cell Extracts; D006133:Growth Substances; D012333:RNA, Messenger; D006861:Hydrogen Peroxide; D002374:Catalase; D005979:Glutathione Peroxidase; D000640:Amitrole