BACKGROUNDTo study the effects of huTNF-α and hIL-2 gene transfection on the expression of MDR1 and LRP genes in lung cancer cell lines.

METHODShuTNF-α and hIL-2 gene plasmids were constructed and transfected into A549, GLC-82, H446 and H460 cells with lipofectinmin. Positive clones were screened out by G418. The expressions of MDR1 and LRP genes were detected at mRNA level by reverse transcription polymerase chain reaction (RT-PCR) in the non transfected cells and the cloned cells.

RESULTSMDR1 gene was positive in A549, GLC-82, H446 and H460 cell lines, LRP gene was positive in A549, GLC-82 and H460 cell lines; The transfected cell lines expressed both huTNF-α and hIL-2 gene, and the A549, H446 and H460 cell lines transfected with hIL-2 gene had no MDR1 expression at mRNA level compared with the non transfected ones.

CONCLUSIONSMDR1 and LRP genes are expressed in lung cancer cell lines, which indicates the presence of intrinsic drug resistance before any form of therapy. MDR1 gene is not expressed in hIL-2 transfected cell lines, which demonstrates that hIL-2 gene modulates the MDR1 gene expression at mRNA level, and may reverse the multidrug resistance of lung cancer.