Fig 2: Expression of RUNX1 gene in primary breast tumors. Figure 3A shows qRT-PCR analysis of the RUNX1 mRNA expressions in primary breast tumors and the adjacent normal samples. 25 of 29 our analyzed tumors have histological grade information. High histological grade tumors (n = 16) have significant reduction of RUNX1 expression compared to low/mid grade tumors (n = 9) or to the adjacent normal samples (n = 11). Data are summarized by box plots. The box represents gene expression values between 1st and 3rd quartiles; the line denotes median. Gene expression difference between high-grade (grade 3) and low/mid-grade (grade 1 plus grade 2) is significant (pvalue = 0.044, by t-test). Figure 3B shows RUNX1 mRNA expression in Ivshina breast microarray dataset. Ivshina breast dataset consists of 289 tumors (68 Grade 1, 166 Grade 2, and 55 Grade 3). Affymetrix U133A array expression data showed progressive reduction of RUNX1 gene (reporter: 210365_at) from Grade 1 to Grade 2 to Grade 3. The progressive reduction of RUNX1 expression in higher grade tumors is highly significant (p-value = 3×10-13 by linear regression analysis). Oncomine™ (Compendia Bioscience, Ann Arbor, MI) was used for this analysis.