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Updated: Jul 16, 2026

A Robust Discovery Platform for the Identification of Novel Mediators of Melanoma Metastasis
07:41

A Robust Discovery Platform for the Identification of Novel Mediators of Melanoma Metastasis

Published on: March 8, 2022

Silencing of tissue factor pathway inhibitor-2 gene in malignant melanomas

Yoshimasa Nobeyama1, Eriko Okochi-Takada, Junichi Furuta

  • 1Carcinogenesis Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, Japan.

International Journal of Cancer
|March 21, 2007
PubMed

Insights

Aberrant methylation silences the TFPI-2 tumor suppressor gene in melanoma, potentially driving metastasis. This gene silencing was reversed by demethylating agents and observed in metastatic melanoma tissues.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Aberrant promoter methylation of tumor suppressor genes is a key mechanism in cancer development.
  • Identifying genes inactivated by methylation is crucial for understanding melanoma progression.

Purpose of the Study:

  • To identify tumor suppressor genes inactivated by promoter CpG island (CGI) methylation in human malignant melanomas.
  • To investigate the role of TFPI-2 gene silencing in melanoma metastasis.

Main Methods:

  • Oligonucleotide microarrays were used to screen for genes upregulated by 5-aza-2'-deoxycytidine (5-aza-dC) in melanoma cell lines.
  • Promoter CGI methylation status and gene expression were analyzed in melanoma cell lines and surgical specimens.
  • TFPI-2 methylation and protein expression were assessed using methylation-specific PCR and immunohistochemistry.

Main Results:

  • Seventy-nine genes were upregulated by 5-aza-dC, with 18 showing promoter CGI methylation in melanoma cell lines.
  • TFPI-2, a repressor of melanoma invasion, was found to be methylated and silenced in melanoma cells, with expression restored by 5-aza-dC.
  • TFPI-2 promoter methylation was detected in 29% of metastatic melanoma specimens but not in primary tumors, correlating with absent TFPI-2 immunoreactivity.

Conclusions:

  • TFPI-2 is epigenetically silenced by promoter CGI methylation in human malignant melanomas.
  • TFPI-2 silencing is associated with melanoma metastasis and may serve as a potential biomarker.

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