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Expression of apoptosome pathway-related transcripts in non-small cell lung cancer

Evzen Krepela1, Jan Procházka, Pavel Fiala

  • 1Clinic of Pneumology and Thoracic Surgery, University Hospital Bulovka and 3rd Faculty of Medicine, Charles University, Budínova 2, 180 81, Prague 8, Czech Republic. krepelae@fnb.cz

Journal of Cancer Research and Clinical Oncology
|October 19, 2005
PubMed
Abstract

Insights

This study reveals that non-small cell lung carcinoma (NSCLC) tissues and cell lines often show increased expression of key apoptosis pathway transcripts, suggesting a subset of NSCLCs may be primed for cell death.

Area of Science:

  • Molecular Biology
  • Oncology
  • Cell Death Research

Background:

  • Cytotoxic therapies rely on the intrinsic apoptosome-mediated caspase activation pathway for tumor cell killing.
  • The expression status of core apoptosome pathway components in non-small cell lung carcinoma (NSCLC) has not been previously evaluated.
  • Understanding these molecular pathways is crucial for developing targeted cancer therapies.

Purpose of the Study:

  • To investigate the expression of transcripts encoding apoptosome pathway components in non-small cell lung carcinoma (NSCLC).
  • To determine if alterations in these transcript levels correlate with NSCLC characteristics.
  • To assess the potential for intrinsic apoptosis priming in NSCLC.

Main Methods:

  • Real-time RT-PCR was used to analyze the expression of Apaf-1, procaspase-9, -3, -6, -7, and Smac.
  • Tumor and lung tissue samples from 65 NSCLC patients were analyzed.
  • Ten NSCLC cell lines were also examined for transcript expression.

Main Results:

  • NSCLC tissues and cell lines exhibited significantly increased mRNA expression of procaspase-9, -3, -6, and Smac compared to normal lung tissue.
  • Apaf-1 mRNA expression was frequently downregulated in NSCLC tumors but upregulated in NSCLC cell lines compared to lung tissue.
  • While procaspase-7 mRNA showed no significant difference, Apaf-1, procaspase-9, and -6 mRNA levels were higher in lung adenocarcinomas than squamous cell lung carcinomas.

Conclusions:

  • A subgroup of NSCLCs demonstrates upregulated expression of transcripts involved in the apoptosome pathway.
  • This suggests that certain NSCLCs may possess an intrinsic predisposition towards apoptosis.
  • These findings could inform future therapeutic strategies targeting apoptosis in NSCLC.

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