Objective     To study the effects of the transefection of antisense human Na

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-H

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exchanger 1 (NHE-1) on the pHi of SGC-7901 and its potential role in the gene therapy for cancers.      Methods     Eukaryotic expression vector pcDNA3.1 encoding antisense NHE-1 was constructed with recombinant DNA technique and transfected into SGC-7901 with liposome DOTAP. The pHi changes of the transfected cells and untransfected cells was detected with a fluorescent probe

BCECF. The proliferation and apoptosis of the cells was studied with flow cytometry.      Results     Antisense NHE-1 gene transfection induced the acidification

decreased proliferation

and elevated apoptosis of SGC-7901 cells.      Concl

usion     The results suggest that NHE-1 gene plays an important role in the regulation of pHi

reproduction and apoptosis of tumor cells. Inhibiting the over-expression and activity of NHE-1 may be of important clinical value.