Objectives/hypothesis: The translation initiation factor eukaryotic initiation factor 4E (eIF4E) binds to the cap of messenger RNA in the first step of messenger RNA recruitment. Overexpression of eIF4E results in the upregulation of specific angiogenic factor basic fibroblast growth factor (bFGF). The study aims to demonstrate that the overexpression of eIF4E could facilitate recognizing initiation start sites for the translation of bFGF and play an important role in the tumorigenesis of laryngeal squamous cell carcinoma.
Study design: Retrospective.
Methods: Paraffin-embedded sections of 37 samples of laryngeal squamous cell carcinoma, 10 samples of vocal cords polyps, and 20 fresh samples of laryngeal squamous cell carcinoma were analyzed using immunohistochemical streptavidin peroxidase technique, Western blot analysis, and reverse transcriptase-polymerase chain reaction.
Results: The overexpression of eIF4E was observed in all 37 paraffin-embedded samples of laryngeal squamous cell carcinoma, whereas no staining was noticed in vocal cords polyps samples. There were significant correlations between the overexpression of protein eIF4E and TN stages, histological grades, local recurrence, and the states of metastasis (P <.01). Moreover, the overexpressions of both bFGF protein and bFGF messenger RNA correlated with the histological grades and the states of metastasis (P <.01), but the overexpression of eIF4E and bFGF did not correlate with age, sex, and tumor sites (P >.05).
Conclusions: Eukaryotic initiation factor 4E can enhance the expression of bFGF at translation level. The eIF4E and bFGF collaborate in tumorigenesis, development, invasion, and metastasis of laryngeal squamous cell carcinoma, in view of which the former can be considered as a tumor molecular marker and an independent prognostic molecular marker of laryngeal squamous cell carcinoma.