Published online Dec 14, 2006. doi: 10.3748/wjg.v12.i46.7472
Revised: September 20, 2006
Accepted: September 26, 2006
Published online: December 14, 2006
AIM: To determine the inhibitory effect of the vector-generated small interfering RNAs (siRNAs) on the expression of the Bcl-XL gene in established human esophageal cancer cells, and to investigate the effect of the Bcl-XL siRNAs on cell growth and apoptosis in esophageal cancer cells.
METHODS: Three siRNA-expressing vectors targeting different sites of the Bcl-XL gene were constructed from pTZ-U6+1 vector. Cultured esophageal cancer cells were transfected with the siRNA-expressing vector (or the control vector) using lipofectamine 2000. Bcl-XL gene expression was determined with semiquantitative RT-PCR assay and Western blotting. Among the three siRNA-expressing vectors, the most highly functional vector and its effect on cell growth and apoptosis in esophageal cancer cells was further analyzed.
RESULTS: Of the three siRNA-expressing vectors, siRNA-expressing vector No.1 was the most potent one which suppressed Bcl-XL mRNA production to 32.5% of that in the untreated esophageal cancer cells. Western blotting analysis showed that siRNA-expressing vector No.1 markedly down-regulated the expression of Bcl-XL in human esophageal cancer cells. Treatment of esophageal cancer cells with siRNA-expressing vector No.1 resulted in inhibition of cell growth and induction of apoptosis.
CONCLUSION: Down-regulation of Bcl-XL by vector-generated small interfering RNAs can suppress cell growth and induce apoptosis in human esophageal cancer cells.