Figure 5. PGE₂ and PGD₂ from RAW 264.7 cells in response to apoptotic cells mediate EMT inhibition in LA-4 cells via their receptors.

RAW 264.7 cells were stimulated with apoptotic Jurkat cells (ApoJ) for 20 h. Conditioned medium (CM) was added to LA-4 cells in the presence of TGF-β1 with or without antagonists of EP2 (AH-6809), EP4 (AH-23848), DP1 (BW-A868C), or DP2 (BAY-u3405) at 10 μM. After 48 or 72 h, morphological changes in the cells were examined by phase-contrast microscopy (Scale bars = 50 μm) (a), and immunoblots of total cell lysates were performed with anti-E-cadherin, N-cadherin, or α-SMA antibodies. Right: Densitometric analysis of the indicated EMT markers’ relative abundances (b,c). (d,e) The amounts of Snail1/2, Zeb1/2, and Twist1 mRNAs in LA-4 cell samples were analyzed by real-time PCR and normalized to that of Hprt mRNA. Values represent the mean ± s.e.m. of three independent experiments. *P < 0.05 compared with control; ⁺P < 0.05 as indicated.