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Published on: January 22, 2019

Antitumor effect of retinoic acid receptor-beta2 associated with suppression of cyclooxygenase-2

Shumei Song1, Baoxiang Guan, Taoyan Men

  • 1Department of Clinical Cancer Prevention, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.

Cancer Prevention Research (Philadelphia, Pa.)
|March 5, 2009
PubMed

Insights

Retinoic acid receptor-beta2 (RAR-beta2) suppresses esophageal tumor growth by downregulating cyclooxygenase-2 (COX-2). This mechanism was observed in some cell lines and oral leukoplakia tissues, suggesting RAR-beta2

Area of Science:

  • Molecular Oncology
  • Cancer Biology

Background:

  • Retinoic acid receptor-beta2 (RAR-beta2) is investigated as a potential tumor suppressor in various cancers.
  • Understanding the molecular mechanisms of RAR-beta2's function is crucial for cancer therapy development.

Purpose of the Study:

  • To investigate the role of RAR-beta2 in esophageal cancer.
  • To elucidate the molecular mechanisms underlying RAR-beta2's antitumor activity, particularly its relationship with cyclooxygenase-2 (COX-2).

Main Methods:

  • Transfection of RAR-beta2 cDNA into esophageal cancer cell lines (TE-1, TE-8).
  • Assessment of tumor cell growth in vitro and tumor formation in nude mice.
  • Analysis of RAR-beta2 and COX-2 mRNA expression in cell lines and patient tissue specimens.
  • Inhibition of COX-2 expression using antisense vectors.

Main Results:

  • RAR-beta2 suppressed tumor growth and formation in TE-8 cells but not TE-1 cells.
  • RAR-beta2's antitumor activity correlated with the suppression of cyclooxygenase-2 (COX-2) expression.
  • Antisense RAR-beta2 induced COX-2 expression, and blocking COX-2 diminished RAR-beta2's effect.
  • RAR-beta2 expression was associated with low COX-2 levels in esophageal cancer tissues.
  • RAR-beta2 induction in oral leukoplakia correlated with reduced COX-2 and clinical improvement.

Conclusions:

  • RAR-beta2 exerts antitumor effects in some esophageal cancer cells, partly mediated by suppressing COX-2.
  • The interplay between RAR-beta2 and COX-2 is a significant factor in esophageal tumorigenesis.
  • Further research is warranted to explore targeting COX-2 to modulate RAR-beta2 activity in various cancers.

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