In this paper, using as a model a human lung carcinoma cell line (A549), expressing a cN-II level (approximately 5.5 nmol min−1 mg−1) higher than the average value measured in a number of different normal tissues (approximately 2 nmol min−1 mg−1) [6], we mimicked inhibition of cN-II by partially silencing the enzyme. The gene discussed is NT5C2; the disease is lung carcinoma.