Inhibitory activity of nuclear factor-kappaB potentiates cisplatin-induced apoptosis in A549 cells.

Whether inhibiting the activity of nuclear factor (NF)-kappaB potentiates cisplatin-induced apoptosis in non-small cell lung cell line A549 cells was investigated. The recombinant plasmid pcDNA3.1 (+)/IkappaBalpha expressing IkappaBalpha was constructed. The in vitro cultured A549 cells were transfected with pcDNA3.1 (+)/IkappaBalpha alone, or pcDNA3.1 (+)/IkappaBalpha combined with cisplatin. The mitochondrial membrane potential (Deltapsim) was determined by rhodamine 123, the activity of caspase-3 was tested by colorimetric assay, and cell apoptosis was detected by flow cytometry with the annexin V /propidium iodide assay. The results showed that the activity of NF-kappaB in A549 cells was inhibited by transfecting pcDNA3.1(+)/IkappaBalpha. Transfection of pcDNA3.1(+)/IkappaBalpha alone did not promote apoptosis. Treatment of cisplatin alone had a little effect on cell apoptosis. Transfection of pcDNA3.1(+)/IkappaBalpha combined with cisplatin treatment significantly induced apoptosis of A549 cells. It was concluded that inhibiting the activity of NF-B potentiated cisplatin-induced apoptosis of A549 cells.