Gene interactions and pathways from curated databases and text-mining
J Appl Toxicol 2011, PMID: 20936651

Comparison of intracellular signalling by insulin and the hypermitogenic AspB10 analogue in MCF-7 breast adenocarcinoma cells.

Oleksiewicz, Martin B; Bonnesen, Christine; Hegelund, Anne Charlotte; Lundby, Anders; Holm, Gitte-Mai Nelander; Jensen, Marianne B; Krabbe, Jonas S

We compared mitogenicity and intracellular signalling by human insulin and the AspB10 (X-10) human insulin analogue in MCF-7 human mammary adenocarcinoma cells. By flow analysis of phosphorylated histone H3 or cell cycle distributions, insulin and X-10 were mitogenic at physiologically relevant concentrations (2 nm to 74 pm range), with X-10 being approximately 3-fold more mitogenic than insulin. By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1, p44/42 MAPK and the EGFR. Blocking with wortmannin, rapamycin and U0126 showed that these signalling events conformed to the canonical PI3K pathway. IRS-1 (Ser302) phosphorylation was abolished by wortmannin and rapamycin, suggesting a feedback from the PI3K pathway on insulin signalling. Compared with equimolar insulin, X-10 caused up to 2-fold higher phosphorylation of all proteins examined in this study. The phosphorylation sites that responded most strongly to insulin were not generally the same as those responding most strongly to X-10. In the PI3K pathway, the most X-10-sensitive protein localized to the translation-regulating arm (p70S6K), with FoxO3a and FoxO1 transcription factors showing a more comparable response to insulin and X-10. Using flow analysis, we confirmed the correlation between insulin-triggered translational activation in G0/G1 (S6 phosphorylation) and S-phase entry by MCF-7 cells. In summary, our findings implicate asymmetrical PI3K pathway activation and specifically stimulation of protein translation in the hypermitogenic effect of insulin analogues such as X-10. It remains to be shown whether these findings are relevant to other human mammary cancer cell types.

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Text Mining Data

MAPK → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1, p44/42 MAPK and the EGFR "

EGFR → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1, p44/42 MAPK and the EGFR "

4E-BP1 → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K, S6 ribosomal protein, 4E-BP1 , FoxO3a, FoxO1, p44/42 MAPK and the EGFR "

FoxO1 → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1 , p44/42 MAPK and the EGFR "

FoxO3a → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a , FoxO1, p44/42 MAPK and the EGFR "

Akt → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt , p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1, p44/42 MAPK and the EGFR "

p70S6K → insulin: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1, Akt, p70S6K , S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1, p44/42 MAPK and the EGFR "

insulin → IRS-1: " By western blotting with phospho-specific antibodies, insulin induced phosphorylation of IRS-1 , Akt, p70S6K, S6 ribosomal protein, 4E-BP1, FoxO3a, FoxO1, p44/42 MAPK and the EGFR "

Manually curated Databases

No curated data.