Figure 2. (A) RUNX1/AML1 protein expression by IHC. From left to right, negative sample of normal endometrial epithelium, positive sample of normal endometrial epithelium (cytoplasmic staining), EEC-positive sample (nuclear staining), and placenta tissue (positive control). (B) RUNX1/AML1 mRNA expression by RT-qPCR, normalized to β-actin, in EEC and normal endometrial samples, according to protein expression score by IHC (concerning nuclear staining only). There was no significant difference of RUNX1/AML1 mRNA expression among stratified groups (P = 0.4589). (C) RUNX1/AML1 mRNA expression by RT-qPCR, normalized to β-actin, in EEC samples of patients with different EEC stages and in normal endometrial epithelium. RUNX1/AML1 mRNA expression is higher in IA stage EEC in comparison with other stage samples (P = 0.0002).