Human epiregulin cDNA was amplified from the lung cancer cell line A549 using RT PCR. After adding 6 His codon to its 3′end, it was cloned into a high efficient secretive Escherichia coli system with alkaline phosphatase promoter( phoA promoter)constructed in our lab and induced for expression. The product was purified one step by Ni NTA column. Amino acid sequence analysis revealed the identity of our product with that previously reported. The product showed strong proliferative effect on fibrobl...