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Updated: Jul 20, 2026

MicroRNA Amplification and Recognition through Locked-nucleic-acid In situ Hybridization as a Novel Detection and Quantification Method
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MicroRNAs 143 and 145 are possible common onco-microRNAs in human cancers

Yukihiro Akao1, Yoshihito Nakagawa, Tomoki Naoe

  • 1Gifu International Institute of Biotechnology, Gifu 504-0838, Japan. yakao@giib.or.jp

Oncology Reports
|September 14, 2006
PubMed

Insights

MicroRNA (miRNA) 143 and 145 levels are significantly reduced in colon cancer cells, suggesting their potential as tumor markers. Restoring these microRNAs inhibited cancer cell growth, highlighting their role in oncogenesis.

Area of Science:

  • Molecular Biology
  • Oncology
  • Genetics

Background:

  • MicroRNAs (miRNAs) are small non-coding RNAs regulating gene expression post-transcriptionally.
  • Reduced miRNA expression is observed in various cancers, potentially due to genomic alterations and epigenetic modifications.
  • Enzymatic processing is crucial for miRNA maturation, linking enzyme activity to miRNA levels.

Purpose of the Study:

  • To investigate the expression levels of miRNA 143 and 145 in colon cancer.
  • To determine the functional role of miRNA 143 and 145 in cancer cell growth.
  • To identify potential therapeutic targets and tumor markers related to these miRNAs.

Main Methods:

  • Quantitative analysis of miRNA expression in cancer cell lines.
  • Transfection of precursor miRNAs into colon cancer cells (DLD-1 and SW480).
  • Assessment of cell growth inhibition post-transfection.
  • Identification of miRNA target genes using molecular techniques.

Main Results:

  • Significantly reduced expression of miRNA 143 and 145 was observed in colon cancer cells and other tested cancer types.
  • Transfection with precursor miRNA 143 or 145 suppressed the growth of colon cancer cells.
  • ERK5 was identified as a direct target gene of miRNA 143.
  • Genomic loci for these miRNAs were confirmed, suggesting defects in early processing stages.

Conclusions:

  • miRNA 143 and 145 downregulation is a common event in colon cancer and potentially other malignancies.
  • These miRNAs exhibit tumor-suppressive functions, making them potential therapeutic agents.
  • miRNA 143 and 145 represent promising biomarkers for cancer diagnosis and prognosis.

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