Down-regulated nuclear Kaiso increases matrilysin transcription and enhances the proliferative and invasive ability of lung cancer cells. A. Invasion assays of BE1, LETP-A-2, and SPC-A-1 cells, which were transfected with shRNA-Kaiso or treated with the addition of a Kaiso antibody. Forty-eight hours after plating on Matrigel, the number of cells invading the lower surface of the filter was far greater in the controls. Data were expressed as mean ± standard deviation (S.D.). Columns, mean (n = 3); error bars, S.D. B. Cell proliferation was determined using the MTT assay. The absorbance at 570 nm represents cell viability at each time point and is a measure of cell proliferation. The growth rates were not markedly different during the first day after transfection, but in each of the latter two days, the growth rate was significantly higher in shRNA-Kaiso groups, compared to controls. For the Kaiso antibody addition groups, significant differences were observed at all three days. Points, mean (n = 3); Bar, S.D. *, p < 0.001.