A: Total RNA from 41 primary HNSCC and 13 normal tissues was labeled and hybridized to Affymetrix U133A Gene Chips as previously reported. Graph shows the average of signal intensity of RUNX3 in 41 HNSCC and 13 normal tissues in microarray analysis. RUNX3 expression level in HNSCC is higher than that of normal tissues. B: Expression of RUNX3 mRNA in 14 HNSCC cell lines (HSC2, HSC3, HSC4, Ca9-22, Ho-1-N-1, Ho-1-U-1, ZA, HOC719-PE, HOC719-NE, HOC621, HOC119, HOC313, TSU and OMI) by RT-PCR. GAPDH was used as a control. C: Expression of RUNX3 mRNA in various cancer cell lines including colon cancer (RKO and HCT116), gastric cancer (MKN-1 and MKN-45), leukemia (HL60), lymphoma (U937) and breast cancer (MCF7 and SK-BR3). GAPDH was used as a control. D: Expression of RUNX3 mRNA in 18 HNSCC cases by RT-PCR. GAPDH was used as a control. E: Expression of RUNX3 protein in 6 HNSCC cell lines (HSC2, HSC3, HSC4, Ca9-22, Ho-1-N-1 and Ho-1-U-1) was examined by Western blot analysis. Cul1 expression was used as a loading control.