(A1-A2) Western blot analysis and densitometry of proteins (B1) hSET1, (B2) HP1a, (B3) SUV39H1, (B4) EZH2, (B5) LSD1, (B6) JMJD2A, and (B7) JMJD3 in 12Z and 22B cells. β-actin protein was measured as an internal control. The 12Z and 22B cells were treated with EP2 and EP4 inhibitors (EP-I) EP2 (AH6809–75 μM) and EP4 (AH23848- μM) for 24h. The experiments were performed as we described in the “Materials and Methods”. *-Control vs. EP2-I/EP4-I, P<0.05. Numerical data are expressed as Mean ± SEM of three (n=3) experiments.