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Optimization of a Multiplex RNA-based Expression Assay Using Breast Cancer Archival Material
11:12

Optimization of a Multiplex RNA-based Expression Assay Using Breast Cancer Archival Material

Published on: August 1, 2018

Deregulated expression of the PER1, PER2 and PER3 genes in breast cancers

Shou-Tung Chen1, Kong-Bung Choo, Ming-Feng Hou

  • 1Department of Molecular Medicine, China Medical University Hospital, Taichung, Taiwan.

Carcinogenesis
|March 26, 2005
PubMed

Insights

Disruptions in circadian rhythm genes (PER1, PER2, PER3) are prevalent in breast cancer, likely due to promoter methylation, not mutations. This deregulation may promote cancer development and offers potential for chronotherapy.

Area of Science:

  • Molecular Biology
  • Oncology
  • Chronobiology

Background:

  • Circadian rhythm disruption is a potential breast cancer risk factor.
  • Molecular mechanisms of circadian gene regulation in breast cancer remain largely unknown.

Purpose of the Study:

  • To investigate molecular alterations in circadian rhythm genes (PER1, PER2, PER3) in Taiwanese breast cancer patients.
  • To explore the role of these genes in breast cancer development and their potential as therapeutic targets.

Main Methods:

  • Immunohistochemical staining to assess protein expression.
  • Methylation-specific PCR and direct sequencing to analyze gene promoters.
  • Analysis of 55 Taiwanese breast cancer cases comparing cancerous and non-cancerous tissues.

Main Results:

  • Over 95% of breast cancer cells showed altered expression of PER1, PER2, and PER3 compared to normal cells.
  • Gene deregulation was attributed to promoter methylation of PER1 or PER2, not genetic mutations.
  • PER gene promoter methylation strongly correlated with c-erbB2 expression (P = 0.017).

Conclusions:

  • Disturbances in circadian PER gene expression, likely via methylation, disrupt normal circadian clock control, potentially aiding cancer cell survival and progression.
  • Differential expression of circadian genes presents a molecular basis for developing chronotherapy for breast cancer.

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