Premium
Mechanisms of unusually high antioxidant activity of RSV‐SR‐transformed cells and of its suppression by activated p21 ras
Author(s) -
Deichman Galina I.,
Kashkina Lydia M.,
Mizenina Olga A.,
Gorojanskaya Erna G.,
Nikiforov Mikhail A.,
Gudkov Andrei V.,
Dyakova Natalia A.,
Komelkov Andrei V.,
Prilutskaya Marina O.,
Kushlinsky Nicolai E.,
Tatosyan Alexander G.
Publication year - 1996
Publication title -
international journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.475
H-Index - 234
eISSN - 1097-0215
pISSN - 0020-7136
DOI - 10.1002/(sici)1097-0215(19960611)66:6<747::aid-ijc7>3.0.co;2-#
Subject(s) - catalase , rous sarcoma virus , microbiology and biotechnology , biology , transfection , glutathione , glutathione peroxidase , peroxidase , glutathione reductase , chemistry , biochemistry , antioxidant , virology , virus , enzyme , gene
We have previously demonstrated that hamster embryo fibroblasts (HEFs) transformed by Rous Sarcoma virus, Schmidt‐Ruppin strain (RSV‐SR) are highly resistant to damage by H 2 O 2 (H 2 O 2 R ), (in contrast to HEFs transformed spontaneously, or by bovine adenovirus and SV40), while N‐ ras transfection of RSV‐SR transformants leads to suppression of pp60 v‐ src and of H 2 O 2 R . In this study we have examined (1) mechanisms of antioxidant activity (AOA) of HEFs transformed by these agents and (2) the possible role of the v‐ src gene in unusually high AOA of RSV‐SR transformants and of activated ras oncogenes in its suppression. All transformants exhibit increased catalase and glutathione peroxidase (GP) activities, while SOD, glutathione and glutathione reductase (GR) were reduced. As compared with other transformants, the significantly higher catalase and the low SOD activities were characteristic of RSV‐SR‐transformants, while an increase in GP was observed in all types of transformants. Correspondingly, RSV‐SR‐transformants showed an extremely high H 2 O 2 ‐catabolizing activity (H 2 O 2 CA ) and no lipid peroxidation chain reaction (LPCR). N‐ ras ‐induced suppression of pp60 v‐ src of RSV‐SR‐transformed HEFs coincided with the suppression of catalase, GP, H 2 O 2 R and H 2 O 2 CA . However, suppression of catalase and GP was also observed in N‐ ras ‐ and Ha‐ ras ‐transfected, spontaneously transformed HEFs. Thus, extremely high catalase activity and suppression of LPCR are apparently the main mechanisms of the unusually high H 2 O 2 R of RSV‐SR transformants, while its suppression by activated ras oncogenes may also take place in some transformants, free of v‐ src activity. © 1996 Wiley‐Liss, Inc.