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Suppression of cell proliferation and signaling transduction by connective tissue growth factor in non-small cell

Wenwen Chien1, Dong Yin, Dorina Gui

  • 1Division of Hematology/Oncology, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, D5022, Los Angeles, CA 90048, USA.

Molecular Cancer Research : MCR
|August 1, 2006
PubMed

Insights

Connective tissue growth factor (CTGF) is often reduced in non-small cell lung cancer (NSCLC). Lower CTGF levels promote lung cancer cell proliferation, suggesting CTGF acts as a tumor suppressor.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Biology

Background:

  • Connective tissue growth factor (CTGF) is a CCN family member involved in cell adhesion, migration, and apoptosis.
  • Understanding CTGF's role in lung tumorigenesis is crucial for developing targeted therapies.

Purpose of the Study:

  • To investigate the expression and function of CTGF in non-small cell lung cancer (NSCLC).
  • To determine if CTGF acts as a tumor suppressor in lung cancer development.

Main Methods:

  • Real-time reverse transcription-PCR and immunohistochemical staining to assess CTGF expression in lung cancer samples and cell lines.
  • Overexpression of CTGF in NSCLC cell lines to evaluate its effects on cellular proliferation and cell cycle.
  • Analysis of downstream signaling pathways, including Akt and ERK phosphorylation, in response to CTGF modulation.

Main Results:

  • CTGF expression was significantly reduced in 57% of 58 NSCLC samples compared to normal lung tissue.
  • CTGF overexpression inhibited proliferation and induced G(0)-G(1) growth arrest in NSCLC cell lines.
  • CTGF overexpression suppressed insulin-like growth factor-I-dependent Akt and epidermal growth factor-dependent ERK phosphorylation.

Conclusions:

  • Decreased CTGF expression is a common feature in NSCLC and correlates with increased tumor cell proliferation.
  • CTGF may function as a secreted tumor suppressor protein in the lung, with its suppression contributing to lung cancer progression.

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