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Updated: Jul 7, 2026

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06:54

Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells

Published on: October 27, 2020

An actin-binding protein Girdin regulates the motility of breast cancer cells

Ping Jiang1, Atsushi Enomoto, Mayumi Jijiwa

  • 1Department of Pathology, Center for Neurological Disease and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Cancer Research
|March 5, 2008
PubMed

Insights

Girdin is a protein crucial for cell movement and organization. This study shows Girdin promotes cancer cell metastasis, highlighting its role in tumor progression and potential as a therapeutic target.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Oncology

Background:

  • Girdin (girders of actin filaments) is an actin-binding protein and Akt substrate involved in cell motility.
  • Aberrant activation of the Akt signaling pathway is common in various cancers.

Purpose of the Study:

  • To investigate the role of Girdin in cancer cell motility and tumor progression.
  • To determine if Girdin is involved in insulin-like growth factor-I (IGF-I)-dependent cell movement.

Main Methods:

  • Expression analysis of Girdin in cancer cell lines and human tumor tissues.
  • In vitro migration and invasion assays using MDA-MB-231 breast cancer cells.
  • In vivo metastasis assays in nude mice using short hairpin interfering RNA (shRNA) against Girdin.

Main Results:

  • Girdin is expressed in various cancer cell lines, including MDA-MB-231, and is phosphorylated upon IGF-I stimulation.
  • Girdin is essential for IGF-I-dependent migration and invasion of MDA-MB-231 cells.
  • Girdin knockdown significantly inhibited the metastasis of MDA-MB-231 cells in vivo.
  • Girdin is highly expressed in human breast, colon, lung, and uterine cervical carcinomas.

Conclusions:

  • Girdin plays a critical role in promoting cancer cell metastasis and tumor progression.
  • Girdin may be a valuable therapeutic target in cancers with activated Akt signaling pathways.

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