RESUMO
<p><b>OBJECTIVE</b>To clone differentially expressed cDNA sequences involved in malignant transformation induced by benzo(a)pyrene metabolite dihydroxyepoxy benzo pyrene (BPDE).</p><p><b>METHOD</b>The malignant transformation of human bronchial epithelial cell line 16HBE induced by BPDE in vitro was used as a model for comparing gene expression between the transformed cells and controls. cDNA representational difference analysis (cDNA-RDA) was performed to isolate differentially expressed cDNA fragment in transformed cells. The cDNA fragments were ligated to pGEM-T vector and transformed into JM109 bacteria. The plasmid DNA were sequenced and compared with data in GenBank by BLASTN.</p><p><b>RESULTS</b>Five cDNA sequences were found to be novel ones and were registered in dbest database, which assigned accession numbers in GenBank are BG354691, BG354692, BG354693, BG354694 and BG354695, respectively. Eight of the remaining cDNA sequences showed sequence homology to those previously reported such as ribosomal protein S23, MLN137, ACTN4, transforming growth factor and G protein gene.</p><p><b>CONCLUSIONS</b>These 13 genes may be involved in BPDE-induced malignant transformation, but their biological characteristics and functions are left to further studies.</p>