Up-regulation of Eukaryotic Elongation Factor-1 Subunits in Breast Carcinoma

Background: Wide evidence suggests the involvement of translation elongation factors (EFs) at the onset of oncogenesis. To investigate the potential role of the EF-1 subunits (A, Bα and Bγ) in the formation and progression of breast cancer, we quantified their expression in human breast tissues and cell lines. Materials and Methods: The mRNA levels of EF-1A, -1Bα and -1Bγ in human breast tissues and cell lines were measured by semi-quantitative RT-PCR and Northern blotting, respectively. Results: The mRNA expression of the three EF-1 subunits was significantly higher in cancerous over normal tissues. However, there was no significant difference in their expression between tumor grades. Overexpression of EF-1 mRNA in breast cancer cell lines were not caused by increased mRNA stability. Conclusion: Although not indicative of tumor grading, the elevated levels of EF-1 subunits are suggestive of their early role in the pathogenesis of breast cancer, possibly through their increased rate of transcription.