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Detection of Alternative Splicing During Epithelial-Mesenchymal Transition
11:48

Detection of Alternative Splicing During Epithelial-Mesenchymal Transition

Published on: October 9, 2014

Differential expression of the splicing regulatory factor genes during two-step chemical transformation in a

T Maeda1, H Hiranuma, A Jikko

  • 1Department of Radiology and Radiation Oncology, Osaka University School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan. tmaeda@radiol.dent.osaka-u.ac.jp

Carcinogenesis
|December 11, 1999
PubMed

Insights

Changes in splicing factor gene expression, including alternative splicing factor/splicing factor 2 (ASF/SF2) and U2 small nuclear ribonucleoprotein particles auxiliary factor 65 (U2AF(65)), occur during cellular transformation, potentially explaining aberrant alternative splicing in tumors.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Cell Biology

Background:

  • Alternative splicing is frequently altered in human tumors.
  • The underlying mechanisms driving these splicing changes during cancer development are not well understood.
  • Splicing regulatory factors play a crucial role in controlling alternative splicing patterns.

Purpose of the Study:

  • To investigate alterations in the expression of key splicing regulatory factors during in vitro cellular transformation.
  • To determine if changes in splicing factor gene expression correlate with the progression of cancer development.
  • To explore the potential link between altered splicing factor expression and aberrant alternative splicing observed in tumor cells.

Main Methods:

  • Utilized a two-step chemical transformation model using BALB/3T3 cells and derived cell lines (MT-5).
  • Examined mRNA expression levels of splicing regulatory factors, including alternative splicing factor/splicing factor 2 (ASF/SF2), heterogeneous nuclear ribonucleoprotein A2 (hnRNP A2), and U2 small nuclear ribonucleoprotein particles auxiliary factor 65 (U2AF(65)), via Northern blotting.
  • Analyzed distinct mRNA isoforms using Reverse Transcription Polymerase Chain Reaction (RT-PCR).

Main Results:

  • ASF/SF2 mRNA levels decreased significantly (2-fold) in both initiated and transformed cells compared to parental cells.
  • hnRNP A2 mRNA expression showed no significant changes across the cell types.
  • U2AF(65) mRNA levels increased substantially (approximately 4.7-fold) with the progression of cellular transformation.
  • Distinct ASF/SF2 mRNA variants were detected in initiated and transformed cells, but not in parental cells.

Conclusions:

  • Gene expression of ASF/SF2 and U2AF(65) is demonstrably altered during in vitro chemical-induced cellular transformation.
  • Differential expression of splicing regulatory factors like ASF/SF2 and U2AF(65) is implicated as a causative factor for aberrant alternative splicing in tumor cells.
  • These findings provide mechanistic insights into how altered splicing contributes to cancer development.

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