Inhibition of phorbol ester‐stimulated phospholipase D activity by chronic tamoxifen treatment in breast cancer cells

FEBS Letters

Anderson, Wayne H¹  Kiss, Zoltan¹ 

[1] The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA

关键词: Phospholipase D activity inhibition;    Tamoxifen;    TAM;    tamoxifen;    ER;    estrogen receptor;    PKC;    protein kinase C;    PLD;    phospholipase D;    PtdCho;    phosphatidylcholine;    PtdEtn;    phosphatidylethanolamine;    PMA;    phorbol 12-myristate 13-acetate;   

DOI  :  10.1016/S0014-5793(96)01377-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have shown that in an estrogen receptor-negative multidrug-resistant subline of MCF-7 human breast carcinoma cells longer-term (24 h), but not shorter-term (30 min), treatments with clinically relevant (2–5 μM) concentrations of tamoxifen (TAM) inhibited phorbol ester-stimulated phospholipase D (PLD) activity by 50–80%. TAM caused these inhibitory effects without inducing membrane translocation or down-regulation of protein kinase C-α, the major mediator of phorbol ester effects on PLD activation. The results raise the possibility that prolonged inhibition of the protein kinase C-α-regulated PLD system may contribute to the cytotoxic effects of tamoxifen in estrogen receptor-negative breast cancer cells.

【 授权许可】

Unknown