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Published on: March 30, 2019

Reduced expression of cell-cycle regulator p27(Kip1) correlates with a shortened survival in non-small cell lung

S Tsukamoto1, K Sugio, T Sakada

  • 1Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.

Lung Cancer (Amsterdam, Netherlands)
|September 15, 2001
PubMed
Abstract

Insights

Reduced expression of p27 protein, a cell cycle regulator, is linked to advanced non-small cell lung cancer. Lower p27 levels indicate a poorer prognosis and reduced survival rates in patients after surgical resection.

Area of Science:

  • Molecular Biology
  • Oncology
  • Cell Cycle Regulation

Background:

  • Cell cycle progression is controlled by cyclin-dependent kinases (CDKs), regulated by cyclins and phosphorylation.
  • p27, a cyclin-dependent kinase inhibitor (CKI), controls G1 to S phase transition by inhibiting cyclin/CDKs.
  • Reduced p27 expression, not mutations, may drive cancer progression.

Purpose of the Study:

  • To investigate the role of p27 protein expression in non-small cell lung cancer (NSCLC).
  • To determine if p27 expression levels correlate with clinicopathological features and patient prognosis.

Main Methods:

  • Analyzed surgically excised tissues from 161 Japanese NSCLC patients.
  • Assessed p27 protein expression using immunohistochemistry.

Main Results:

  • Reduced p27 expression was observed in 39.0% of cases.
  • Lower p27 levels correlated with advanced NSCLC stage.
  • Reduced p27 expression was an independent poor prognostic indicator, associated with significantly lower 5-year survival rates in patients with complete resection.

Conclusions:

  • p27 protein expression serves as a valuable prognostic biomarker in NSCLC.
  • It helps identify patient subsets with good or poor prognosis following surgical resection.

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