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X-radiation induces non-small-cell lung cancer apoptosis by upregulation of Axin expression

Yang Han1, Yan Wang, Hong-Tao Xu

  • 1Department of Pathology, College of Basic Medical Sciences and First Affiliated Hospital of China Medical University, Shenyang, PR China.

International Journal of Radiation Oncology, Biology, Physics
|September 9, 2009
PubMed
Abstract

Insights

Axis inhibition (Axin) expression is lower in non-small-cell lung cancer (NSCLC) and correlates with poor prognosis. Elevated Axin post-X-ray exposure enhances apoptosis, indicating its potential as a radiosensitivity marker in NSCLC.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cancer Research

Background:

  • Axis inhibition (Axin) is a key negative regulator of the Wnt signaling pathway.
  • Understanding Axin's role in cancer progression and treatment response is crucial for developing targeted therapies.

Purpose of the Study:

  • To investigate the correlation between Axin expression and radiosensitivity in non-small-cell lung cancer (NSCLC).
  • To identify Axin as a potential biomarker for predicting patient response to X-ray therapy.

Main Methods:

  • Analysis of Axin and p53 expression in NSCLC tissues and cell lines (A549, BE1) using immunohistochemistry and RT-PCR.
  • Assessment of apoptosis via TUNEL assay and FACS analysis.
  • Measurement of caspase-3 activity and phospho-JNK expression.

Main Results:

  • Lower Axin expression was observed in NSCLC tissues compared to normal lung tissues, correlating with advanced TNM staging and lymph node metastasis.
  • Axin expression positively correlated with apoptosis and better patient prognosis.
  • X-radiation increased Axin expression, leading to elevated caspase-3 activity and enhanced apoptosis, particularly when combined with Axin.
  • Axin-induced apoptosis involved the p53 pathway in cells with intact p53 and the JNK pathway in cells with mutated p53 (p53(mt)).

Conclusions:

  • Axin plays a dual role in apoptosis induction, utilizing the p53 pathway or the JNK pathway depending on p53 status.
  • Elevated Axin expression following X-ray exposure serves as a reliable indicator of radiosensitivity in NSCLC.

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