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Updated: Aug 17, 2026

MicroRNA Detection in Prostate Tumors by Quantitative Real-time PCR (qPCR)
08:30

MicroRNA Detection in Prostate Tumors by Quantitative Real-time PCR (qPCR)

Published on: May 16, 2012

Dual-specificity phosphatase 1 and serum/glucocorticoid-regulated kinase are downregulated in prostate cancer

Hanna E Rauhala1, Kati P Porkka, Teemu T Tolonen

  • 1Laboratory of Cancer Genetics, Institute of Medical Technology, University of Tampere and Tampere University Hospital, University of Tampere, Tampere, Finland.

International Journal of Cancer
|June 28, 2005
PubMed

Insights

Epigenetic silencing of tumor suppressor genes is common in cancer. This study identified dual-specificity phosphatase 1 (DUSP1) and serum/glucocorticoid regulated kinase (SGK) as downregulated in prostate cancer, suggesting early involvement in tumorigenesis.

Area of Science:

  • Cancer Biology
  • Epigenetics
  • Prostate Cancer Research

Background:

  • Tumor suppressor gene inactivation via epigenetic silencing is a hallmark of cancer.
  • Epigenetic dysregulation contributes to prostate cancer development and progression.
  • Identifying epigenetically silenced genes is crucial for understanding cancer biology.

Purpose of the Study:

  • To identify epigenetically downregulated genes in the PC-3 prostate cancer cell line.
  • To investigate the expression patterns of candidate genes in clinical prostate cancer samples.
  • To determine the potential role of DUSP1 and SGK in prostate cancer tumorigenesis.

Main Methods:

  • Combined DNA demethylation and histone deacetylation inhibition with suppression subtraction hybridization (SSH) and cDNA microarrays.
  • Validated gene expression using real-time quantitative RT-PCR and immunohistochemistry in clinical samples.
  • Analyzed promoter methylation using genomic bisulphite sequencing.

Main Results:

  • Identified 11 epigenetically regulated genes upregulated after treatment.
  • Dual-specificity phosphatase 1 (DUSP1) and serum/glucocorticoid regulated kinase (SGK) mRNA levels were lower in hormone-refractory prostate cancer.
  • DUSP1 and SGK proteins were significantly downregulated in most prostate carcinomas compared to benign or pre-malignant tissues, without promoter hypermethylation.
  • Spermidine/spermine N1-acetyltransferase (SAT) expression was also analyzed.

Conclusions:

  • Downregulation of DUSP1 and SGK is a common event in prostate cancer.
  • The observed downregulation of DUSP1 and SGK appears to be independent of promoter hypermethylation.
  • These findings suggest that DUSP1 and SGK downregulation is an early event in prostate cancer development and may play a significant role in tumorigenesis.

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