Two 23-mer unmodified oligodeoxynucleotides have been synthesized, one to hybridize with the region across the transcription initiation site of TGFa cDNA called antisense, and the second with an identical base composition, but the nucleotide sequence randomized. The random oligodeoxynucleotide was used to control for any non-specific effects of the oligodeoxynucleotides. TGFα antisense inhibited cell proliferation and DNA synthesis from 31% to 44% and 25.8% to 88.0% respectively. This effect is specific and dose-responded. However, at the same condition, the inhibition by random is only 10% to 17% and 17% to 27%.This effect is not dose-responded. By RNA dot blot analysis，the addition of 3μmol/L TGFa antisense and random upon BIU87 cells resulted in 61.4% and 42.5% inhibition in TGFa mRNA expression respectively. These results suggested that TGFa may play an important role in the proliferation of BIU87 cell line and provide a rational basis for the development of selective cancer therapeutical approaches.