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Redox-mediated bypass of restriction point via skipping of G1pm.

ABSTRACT: BACKGROUND: It is well known that cancer cells bypass the restriction point, R, and undergo uncontrolled cell proliferation. HYPOTHESIS AND EVIDENCE: We suggest here that fibrosarcoma cells enter G1ps directly from M, skipping G1pm, hence bypassing R, in response to redox modulation. Evidence is presented from the published literature that demonstrate a shortening of the cycle period of transformed fibroblasts (SV-3T3) compared to the nontransformed 3T3 fibroblasts, corresponding to the duration of G1pm in the 3T3 fibroblasts. Evidence is also presented that demonstrate that redox modulation can induce the CUA-4 fibroblasts to bypass R, resulting in a cycle period closely corresponding to the cycle period of fibrosarcoma cells (HT1080). CONCLUSION: The evidence supports our hypothesis that a low internal redox potential can cause fibrosarcoma cells to skip the G1pm phase of the cell cycle.

SUBMITTER: Hoffman A

PROVIDER: S-EPMC1557840 | biostudies-literature | 2006

REPOSITORIES: biostudies-literature

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Redox-mediated bypass of restriction point via skipping of G1pm.

Hoffman Arnold A Greene James J JJ Spetner Lee M LM Burke Michael M

Theoretical biology & medical modelling 20060725

<h4>Background</h4>It is well known that cancer cells bypass the restriction point, R, and undergo uncontrolled cell proliferation.<h4>Hypothesis and evidence</h4>We suggest here that fibrosarcoma cells enter G1ps directly from M, skipping G1pm, hence bypassing R, in response to redox modulation. Evidence is presented from the published literature that demonstrate a shortening of the cycle period of transformed fibroblasts (SV-3T3) compared to the nontransformed 3T3 fibroblasts, corresponding to ...[more]

PMID: 16867189

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