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The vitamin A family can significantly decrease the expression of ERbeta of ERs positive breast cancer cells in the

Ewa Czeczuga-Semeniuk1, Katarzyna Jarzabek, Dorota Lemancewicz

  • 1Department of Reproduction and Gynecological Endocrinology, Medical University of Biaystok, 15-276 Białystok, M. Skłodowskiej-Curie 24 A, Poland. czeczuga@wp.pl

Gynecological Endocrinology : the Official Journal of the International Society of Gynecological Endocrinology
|April 3, 2009
PubMed

Insights

Vitamin A compounds, particularly beta-carotene, enhance paclitaxel

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Taxanes, such as paclitaxel, are effective in treating breast cancer.
  • Estrogen receptors (ERs) play a crucial role in the development of ER-positive breast cancer.
  • Vitamin A compounds (retinoids) are being investigated for their potential role in cancer therapy.

Purpose of the Study:

  • To investigate the impact of vitamin A compounds on the cytotoxic effects of paclitaxel.
  • To examine how vitamin A compounds influence estrogen receptor (ER) expression in breast cancer cells.
  • To evaluate the combined effects of vitamin A derivatives, paclitaxel, and hormonal therapies (estradiol, tamoxifen) on cell proliferation.

Main Methods:

  • Culturing MCF-7 breast cancer cells.
  • Treating cells with paclitaxel, various vitamin A compounds (retinol, beta-carotene, retinoids, lycopene), estradiol, and tamoxifen.
  • Assessing cell proliferation using cell counting.
  • Quantifying estrogen receptor alpha (ERalpha) and ERbeta messenger RNA (mRNA) expression using quantitative PCR.

Main Results:

  • Beta-carotene and retinol, but not other retinoids, modulated paclitaxel's activity.
  • Beta-carotene significantly reduced the percentage of proliferating cells.
  • Combinations of vitamin A derivatives with paclitaxel and tamoxifen significantly decreased cell proliferation compared to paclitaxel alone.
  • Paclitaxel increased ERalpha and ERbeta mRNA expression.
  • 9-cis retinoic acid combined with paclitaxel demonstrated the strongest inhibition of ERalpha and ERbeta mRNA transcription, suggesting synergistic down-regulation of ERbeta.

Conclusions:

  • Certain vitamin A compounds, notably beta-carotene, can enhance the anti-cancer effects of paclitaxel in breast cancer cells.
  • Vitamin A derivatives, particularly 9-cis retinoic acid, can synergistically down-regulate estrogen receptor beta expression when combined with paclitaxel.
  • These findings support the potential therapeutic use of retinoids in combination with standard treatments for estrogen receptor-positive breast cancer.

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