To explore whether metalloproteinase activity is important for miR-1 suppression in lung cancer cells, we treated the cells with the broad-spectrum metalloproteinase inhibitor BB94, which has been demonstrated to suppress ADAM9 expression [3], and then detected the expression levels of CDCP1 and miR-1 by quantitative reverse transcription- PCR. The gene discussed is ADAM9; the disease is lung cancer.