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Enhancement of Apoptotic and Autophagic Induction by a Novel Synthetic C-1 Analogue of 7-deoxypancratistatin in Human Breast Adenocarcinoma and Neuroblastoma Cells with Tamoxifen
19:44

Enhancement of Apoptotic and Autophagic Induction by a Novel Synthetic C-1 Analogue of 7-deoxypancratistatin in Human Breast Adenocarcinoma and Neuroblastoma Cells with Tamoxifen

Published on: May 30, 2012

Can hormone "resistant" breast cancer cells be inappropriately stimulated by tamoxifen?

K B Horwitz1

  • 1University of Colorado Health Sciences Center, Denver 80262.

Annals of the New York Academy of Sciences
|June 11, 1993
PubMed

Insights

Tumor cell heterogeneity, driven by estrogen receptor (ER) mutations, causes varied responses to tamoxifen. This suggests caution in using tamoxifen for breast cancer prevention due to potential mixed cellular effects.

Area of Science:

  • Oncology
  • Molecular Biology
  • Endocrinology

Background:

  • Breast tumors exhibit molecular heterogeneity, particularly in estrogen receptor (ER) forms.
  • This heterogeneity is linked to cellular diversity observed in progesterone receptor (PR) and DNA ploidy analyses.
  • Such cellular diversity may explain inconsistent responses to tamoxifen therapy.

Purpose of the Study:

  • To investigate the link between ER molecular heterogeneity and cellular heterogeneity in breast tumors.
  • To understand how cellular heterogeneity influences tamoxifen response.
  • To evaluate the predictive value of PR heterogeneity for tamoxifen treatment outcomes.

Main Methods:

  • Analysis of molecular heterogeneity of ER in breast tumor cells.
  • Assessment of cellular heterogeneity using PR and DNA ploidy analysis in cell subpopulations.
  • Utilizing FCM immunoassay for rapid measurement of tumor cell subpopulations.

Main Results:

  • Molecular heterogeneity of ER contributes to cellular heterogeneity in breast cancer.
  • Tamoxifen treatment remodels mixed subpopulations of breast cancer cells, leading to varied responses (inhibition or stimulation).
  • PR heterogeneity in tumors may predict a mixed response to antiestrogen therapy.

Conclusions:

  • Cellular heterogeneity, influenced by ER and PR variations, dictates tamoxifen response in breast cancer.
  • Identifying specific tumor cell subpopulations through assays like FCM immunoassay is crucial for predicting treatment outcomes.
  • The use of tamoxifen as a chemopreventive agent in high-risk women warrants careful consideration due to potential adverse effects from mixed cellular responses.

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