Abstract
The effects of flavin-containing oxidase enzymes on cellular progression from G{sub 1} to S phase of the cell cycle were examined in normal human diploid fibroblasts by use of the cumulative labeling index method. Significant transient arrests in G{sub 1} occurred when quiescent cell populations incubated with diphenyliodonium (DPI) for a 20 h period at concentrations as low as 0.05 {mu}M were stimulated to proliferate by subculturing to low density in control growth medium. Quiescent cells pre-treated with DPI and subcultured in DPI-containing growth medium were permanently arrested in G{sub 1}. Induction of this G{sub 1} checkpoint was associated with activation of the p53/p21{sup Waf1} signaling pathway. Incubation of G{sub 0}/G{sub 1} phase cells with DPI (0.05-0.2 {mu}M) resulted in significant decreases in the expression levels of cyclin D1 and p21{sup Waf1}; no effect was detected on cyclin A expression. Collectively, these results suggest that DPI-sensitive signaling primarily regulates early G{sub 1} events that lead to S-phase transition. Furthermore, they support a critical role for membrane originating oxidants in the regulation of cellular proliferation pathways.
Venkatachalam, Perumal;
[1]
Toledo, Sonia M. de;
[1]
Azzam, Edouard I
[1]
- Department of Radiology, UMDNJ-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103 (United States)
Citation Formats
Venkatachalam, Perumal, Toledo, Sonia M. de, and Azzam, Edouard I.
Flavin-containing oxidases regulate progression from G{sub 1} to S phase of the cell cycle in normal human diploid fibroblasts.
United Kingdom: N. p.,
2005.
Web.
doi:10.1016/j.radphyschem.2004.01.010.
Venkatachalam, Perumal, Toledo, Sonia M. de, & Azzam, Edouard I.
Flavin-containing oxidases regulate progression from G{sub 1} to S phase of the cell cycle in normal human diploid fibroblasts.
United Kingdom.
https://doi.org/10.1016/j.radphyschem.2004.01.010
Venkatachalam, Perumal, Toledo, Sonia M. de, and Azzam, Edouard I.
2005.
"Flavin-containing oxidases regulate progression from G{sub 1} to S phase of the cell cycle in normal human diploid fibroblasts."
United Kingdom.
https://doi.org/10.1016/j.radphyschem.2004.01.010.
@misc{etde_20620257,
title = {Flavin-containing oxidases regulate progression from G{sub 1} to S phase of the cell cycle in normal human diploid fibroblasts}
author = {Venkatachalam, Perumal, Toledo, Sonia M. de, and Azzam, Edouard I}
abstractNote = {The effects of flavin-containing oxidase enzymes on cellular progression from G{sub 1} to S phase of the cell cycle were examined in normal human diploid fibroblasts by use of the cumulative labeling index method. Significant transient arrests in G{sub 1} occurred when quiescent cell populations incubated with diphenyliodonium (DPI) for a 20 h period at concentrations as low as 0.05 {mu}M were stimulated to proliferate by subculturing to low density in control growth medium. Quiescent cells pre-treated with DPI and subcultured in DPI-containing growth medium were permanently arrested in G{sub 1}. Induction of this G{sub 1} checkpoint was associated with activation of the p53/p21{sup Waf1} signaling pathway. Incubation of G{sub 0}/G{sub 1} phase cells with DPI (0.05-0.2 {mu}M) resulted in significant decreases in the expression levels of cyclin D1 and p21{sup Waf1}; no effect was detected on cyclin A expression. Collectively, these results suggest that DPI-sensitive signaling primarily regulates early G{sub 1} events that lead to S-phase transition. Furthermore, they support a critical role for membrane originating oxidants in the regulation of cellular proliferation pathways.}
doi = {10.1016/j.radphyschem.2004.01.010}
journal = []
issue = {2-3}
volume = {72}
journal type = {AC}
place = {United Kingdom}
year = {2005}
month = {Feb}
}
title = {Flavin-containing oxidases regulate progression from G{sub 1} to S phase of the cell cycle in normal human diploid fibroblasts}
author = {Venkatachalam, Perumal, Toledo, Sonia M. de, and Azzam, Edouard I}
abstractNote = {The effects of flavin-containing oxidase enzymes on cellular progression from G{sub 1} to S phase of the cell cycle were examined in normal human diploid fibroblasts by use of the cumulative labeling index method. Significant transient arrests in G{sub 1} occurred when quiescent cell populations incubated with diphenyliodonium (DPI) for a 20 h period at concentrations as low as 0.05 {mu}M were stimulated to proliferate by subculturing to low density in control growth medium. Quiescent cells pre-treated with DPI and subcultured in DPI-containing growth medium were permanently arrested in G{sub 1}. Induction of this G{sub 1} checkpoint was associated with activation of the p53/p21{sup Waf1} signaling pathway. Incubation of G{sub 0}/G{sub 1} phase cells with DPI (0.05-0.2 {mu}M) resulted in significant decreases in the expression levels of cyclin D1 and p21{sup Waf1}; no effect was detected on cyclin A expression. Collectively, these results suggest that DPI-sensitive signaling primarily regulates early G{sub 1} events that lead to S-phase transition. Furthermore, they support a critical role for membrane originating oxidants in the regulation of cellular proliferation pathways.}
doi = {10.1016/j.radphyschem.2004.01.010}
journal = []
issue = {2-3}
volume = {72}
journal type = {AC}
place = {United Kingdom}
year = {2005}
month = {Feb}
}