(A) The differentially expressed markers for EMT and basal and luminal breast cancer from MDA-MB231 cells and the corresponding stable clone with knockdown of G9a expression were analyzed by quantitative RT-PCR. (B) Kaplan-Meier overall survival curve separates the tumors (from GSE1456) into 3 groups with expression of a 9-gene prognostic signature (top panel). Expression of the 9-gene signature in 159 breast cancer patients is shown in the heatmap (bottom panel). Top bars: tumor grade (1: blue, 2: pink, 3: red) and tumor subtypes (normal-like: blue, luminal A: yellow, luminal B: orange, basal: pink, HER2-positive: red]). P1, probe 1; P2, probe 2. (C) A proposed model to illustrate the interaction of Snail with G9a and DNMTs leading to E-cadherin promoter methylation and EMT induction (see Discussion).