Measurement of steroid hormone receptors in breast cancer patients on tamoxifen

@article{Encarnacion2004MeasurementOS,
  title={Measurement of steroid hormone receptors in breast cancer patients on tamoxifen},
  author={Carlos A. Encarnacion and D. R. Ciocca and William L. McGuire and Gary M. Clark and Suzanne A. W. Fuqua and C. Kent Osborne},
  journal={Breast Cancer Research and Treatment},
  year={2004},
  volume={26},
  pages={237-246}
}
SummaryEstrogen (ER) and progesterone receptor (PgR) positive breast tumors often respond to tamoxifen, but ultimately progress as they become tamoxifen resistant. An accurate assessment of receptor status in specimens from tamoxifen-resistant patients could help to understand potential mechanisms of resistance and to predict response to second line hormonal therapies. However, since tamoxifen itself can affect ER and PgR determinations, assay results can be misleading. We measured ER and PgR… 

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Results indicate a prominent role for alternative growth control pathways independent of ER signalling in intrinsic tamoxifen resistance of ER-positive breast carcinomas.

Mechanisms of tamoxifen resistance

Pure steroidal antiestrogens such as ICI 182,780 are capable of reversing tamoxifen- Stimulated as well as estrogen-stimulated growth of these resistant tumors, and are now in clinical trials for this purpose.

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Role of the Androgen Receptor in Human Breast Cancer

The presence of structurally altered AR in breast cancers may account for unresponsiveness to MPA treatment following failure of tamoxifen therapy, and identification of androgen-regulated genes may lead to new possibilities for the hormonal treatment of breast cancer.

Steroid Receptor Imaging in Breast Cancer.

Molecular changes in tamoxifen-resistant breast cancer: relationship between estrogen receptor, HER-2, and p38 mitogen-activated protein kinase.

  • M. GutiérrezS. Detre M. Dowsett
  • Medicine, Biology
    Journal of clinical oncology : official journal of the American Society of Clinical Oncology
  • 2005
C Crosstalk between ER, HER-2, p38, and ERK may contribute to tamoxifen resistance and may provide molecular targets to overcome this resistance.
...

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