Objective: To investigate the effects of a phosphatase and tensin homologue (PTEN) antisense oligonucleotide on PTEN and mammalian target of rapamycin (mTOR) mRNA and protein, cell proliferation and apoptosis in oesophageal squamous cell carcinoma (OCSS) cell lines.
Methods: EC9706 and EC1 cells were transfected with PTEN antisense oligonucleotide, sense oligonucleotide or nonsense oligonucleotide. Cell proliferation and apoptosis were quantified. Immuno cyto chemistry and in situ hybridization were used to determine PTEN and mTOR protein and mRNA levels, respectively.
Results: Transfection with PTEN antisense oligonucleotide dose- and time-dependently enhanced cell proliferation and inhibited apoptosis in both EC9706 and EC1 cells. PTEN mRNA and protein were significantly downregulated, and mTOR protein and mRNA were significantly upregulated.
Conclusion: These data suggest that PTEN is an important tumour suppressor gene in the development of OSCC.