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Epigenetic silencing of LRRC3B in colorectal cancer

Xiao Qing Tian1, Yanjie Zhang, Danfeng Sun

  • 1Shanghai Jiao-Tong University School of Medicine Renji Hospital, Shanghai Institute of Digestive Disease, Shanghai, PR China.

Scandinavian Journal of Gastroenterology
|September 26, 2008
PubMed
Abstract

Insights

Tumor suppressor gene LRRC3B (leucine-rich repeat containing 3B) methylation is frequent in colorectal cancer (CRC), suggesting its potential as a diagnostic biomarker. This finding aids in developing new strategies for CRC diagnosis and therapy.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Tumor suppressor gene silencing via promoter hypermethylation is crucial in colorectal cancer (CRC) pathogenesis.
  • Aberrant DNA hypermethylation in CRC can be tumor-specific, offering potential for early diagnosis.
  • Identifying novel methylation-related genes is key for developing new therapeutic and diagnostic strategies for CRC.

Purpose of the Study:

  • To identify novel methylation-related genes for therapeutic and diagnostic strategies in colorectal cancer (CRC).
  • To investigate the role of LRRC3B (leucine-rich repeat containing 3B) as a potential methylation-specific gene in CRC.

Main Methods:

  • Utilized gene expression microarray to identify methylation-sensitive genes in the SW1116 colon cancer cell line after treatment with 5-aza-2'-deoxycytidine (5-aza-dC).
  • Employed promoter microarray analysis to pinpoint cancer-specific, methylation-related genes in CRC patients.
  • Confirmed LRRC3B promoter methylation in primary CRC using methylation-specific polymerase chain reaction (MSP) and assessed gene expression via real-time PCR.

Main Results:

  • Gene expression microarray identified 253 upregulated genes in SW1116 cells post-5-aza-dC treatment.
  • LRRC3B was identified as a potential methylation-specific gene through promoter microarray analysis.
  • Frequent LRRC3B methylation (77%) was observed in primary CRC tissues, with higher intensity compared to non-cancerous tissues. Decreased LRRC3B expression was noted in 55% of cancer tissues.

Conclusions:

  • LRRC3B functions as a novel methylation-sensitive tumor suppressor gene in colorectal cancer (CRC).
  • LRRC3B methylation exhibits significant tumor specificity, positioning it as a potential biomarker for CRC diagnosis.
  • These findings support the development of novel diagnostic and therapeutic approaches for CRC targeting LRRC3B.

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