Effects of EP4 receptor antagonist on the malignant phenotypes of androgen-independent prostate cancer DU145 cells

Objective The EP4 receptor is proved to be closely related to the development and progression of cancer. This study is to examine the anti-tumor effects of the EP4 antagonist on androgen-independent prostate cancer( AIPC) DU145 cells in vitro. Methods We detected the expression levels of EP4 mRNA and protein in the DU145 cells by quantitative real-time PCR and Westernblot,and observed the inhibitory effect of the EP4 antagonist ONO-AE3-208 on the proliferation of the AIPC DU145 cells by MTT, wound-healing test,and Transwell invasion assay,with the known extremely lowly expressed LNCaP and LNCaP / mock cells as the control. Results Quantitative real-time PCR showed that the expression level of EP4 mRNA in the DU145 cells was 4. 698 and 8. 137 times higher respectively than those in the LNCaP and LNCaP / mock cells,and the EP4 protein was also highly expressed. The EP4 antagonist ONO-AE3-208 exhibited no significant time- and concentration-dependent influence on the proliferation of the DU145 cells( P 0. 05). After treated with ONO-AE3-208 at 10 μmol/L for 24 hours,the DU145 cells showed a marked lower rate of migration than the control( [16. 231 ± 4. 112]% vs [48. 710 ± 7. 219]%, P 0. 01). After 24-hour intervention with ONO-AE3-208 at 0. 1, 1. 0,and 10 μmol / L,the numbers of the DU145 cells that had invaded the inferior chamber were 27. 4 ± 4. 5,8. 6 ± 4. 0,and 13. 6 ± 5. 0 respectively,significantly lower than 38. 8 ± 5. 2 in the control group( P 0. 05). Conclusion The EP4 receptor is highly expressed in AIPC DU145 cells. The EP4 antagonist ONO-AE3-208 does not affect the proliferation of the DU145 cells,but can significantly inhibit their migration and invasion abilities.