Phosphorylated eukaryotic translation initiation factor 4 (eIF4E) is elevated in human cancer tissues

Songqing Fan1, Suresh S Ramalingam, John Kauh

  • 1Department of Hematology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA.

Insights

Phosphorylated eukaryotic translation initiation factor 4E (p-eIF4E) is significantly elevated in human cancers compared to normal tissues. This finding suggests p-eIF4E plays a role in early tumorigenesis and is a potential therapeutic target.

Area of Science:

  • Molecular Biology
  • Oncology
  • Biochemistry

Background:

  • Eukaryotic translation initiation factor 4E (eIF4E) regulates protein synthesis and is implicated in cancer.
  • eIF4E phosphorylation by MAPK/Mnk pathways is crucial for its oncogenic activity.
  • Expression patterns of phosphorylated eIF4E (p-eIF4E) in human solid tumors remain largely uncharacterized.

Purpose of the Study:

  • To investigate the expression levels and patterns of p-eIF4E in a diverse range of human cancer tissues.
  • To compare p-eIF4E expression in cancerous tissues versus adjacent normal tissues.
  • To explore the correlation between p-eIF4E expression and clinicopathological features, including tumor stage and lymph node metastasis.

Main Methods:

  • Utilized three tissue microarrays comprising 380 human cancer cases and 146 adjacent normal tissues.
  • Performed immunohistochemical staining to detect p-eIF4E positive staining.
  • Analyzed staining intensity and frequency across different cancer types and stages.

Main Results:

  • p-eIF4E positive staining was observed in 63.4% of cancers versus 30.1% in normal tissues (p < 0.001).
  • No significant difference in p-eIF4E staining was found between cancers with or without lymph node metastasis.
  • Early-stage lung, gastric, and colorectal cancers showed significantly higher p-eIF4E staining than late-stage counterparts (p < 0.05).

Conclusions:

  • p-eIF4E is significantly upregulated in human cancers, particularly during early stages of tumorigenesis.
  • These findings highlight the critical role of p-eIF4E in cancer development.
  • p-eIF4E represents a promising therapeutic target for various malignancies.

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