Invasion assay in monoculture or coculture models.

<p>(a) Schematic diagram of the invasion assay and cellular changes. Carcinoma cells on the transwell penetrate the collagen membrane when cocultured with fibroblasts and then finally attach to the lower surface of the transwell. (b–g) Cocultured YD-10B (b and c), YD-38 (d and e), and HSC-2 (f and g) cells either untreated (b, d, and f) or treated with 1 ng/ml rhBMP-2 (c, e, and g). (h) Quantification of the invasion ability of OSCC cells. Data shown are means of three independent repeats, and error bars indicate standard deviation. *P<0.05 compared to the control.