CFL1 and cancer: In the Boyden chamber assay, which mimics invasion of cancer cells across a basement membrane, the number of cofilin-knocked down SCC-9 and CAL 27 cells that invaded across the Matrigel membrane was decreased compared to cells transfected with control siRNA (SCC-9: mean number of cells/field  =  31.5 versus 173.5, Student’s t test, p<0.001; CAL 27: mean number of cells/field  =  42.3 versus 292, Student’s t test, p<0.05) (Figure 4D).