IL-8 (100 nM) significantly decreased the length of the CF cells by 19 ± 3% compared to 8 ± 2% in control cells (p <0.05) whereas the changes in length of control and CF cells treated with vehicle (1.5 ± 1% and 3.7 ± 3%, respectively) did not differ significantly. The gene discussed is CXCL8; the disease is cystic fibrosis.