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Updated: Jul 14, 2026

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

Latent transforming growth factor binding protein 4 (LTBP-4) is downregulated in human mammary adenocarcinomas in

Susanne Mauel1, Bianca Kruse, Benjamin Etschmann

  • 1Institute of Veterinary Pathology, Freie Universität Berlin, Berlin, Germany.

APMIS : Acta Pathologica, Microbiologica, Et Immunologica Scandinavica
|June 7, 2007
PubMed

Insights

Latent transforming growth factor-beta binding protein-4 (LTBP-4) is downregulated in human breast tumors, potentially reducing TGF-beta 1 availability and influencing cancer development. This suggests a compensatory upregulation of TGF-beta 2.

Area of Science:

  • Oncology
  • Cell Biology
  • Biochemistry

Background:

  • Transforming growth factor-beta (TGF-β) inhibits epithelial cell proliferation and plays a role in human mammary tumor development.
  • Latent transforming growth factor-beta binding proteins (LTBP-1, -3, and -4) modulate TGF-β activity.
  • Altered TGF-β signaling is implicated in various cancers, including breast cancer.

Purpose of the Study:

  • To investigate the expression profiles of TGF-β1, TGF-β2, and LTBP-4 in human mammary carcinoma cell lines and tumors.
  • To analyze the role of LTBP-4 in TGF-β bioavailability within the context of breast cancer.
  • To understand the relationship between LTBP-4 expression and TGF-β isoforms in mammary carcinogenesis.

Main Methods:

  • Quantitative analysis of LTBP-4 expression at both transcriptional and protein levels in human mammary tumors and adjacent normal tissues.
  • Assessment of TGF-β1 and TGF-β2 protein levels in human mammary carcinoma cell lines versus primary mammary epithelial cells.
  • In vivo and in vitro experimental conditions were employed.

Main Results:

  • LTBP-4 expression was significantly downregulated in all investigated human mammary tumors compared to healthy tissues.
  • Protein levels of TGF-β1 were downregulated, while TGF-β2 levels were upregulated in mammary carcinoma cell lines.
  • The reduction of LTBP-4 in neoplasms correlates with decreased extracellular deposition and bioavailability of TGF-β1.

Conclusions:

  • Downregulation of LTBP-4 in breast cancer may lead to reduced TGF-β1 bioavailability, potentially contributing to carcinogenesis.
  • Upregulation of TGF-β2 in carcinoma cells suggests a compensatory mechanism in response to altered TGF-β1 signaling.
  • LTBP-4 plays a functional role in regulating TGF-β bioavailability, impacting human mammary tumor development.

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