PTGS2 and neoplasm: Kato et al (2001) reported that the respective mean IC50 values for Cox-1 and Cox-2 IC50 (10−6 M), and the Cox-1/Cox-2 ratio of each drug were as follows: celecoxib, 82, 6.8, 12; etodolac, >100, 53, >1.9; NS-398, 125, 5.6, 22. Indeed etodolac has the lowest Cox-2 selectivity and highest Cox-2 IC50 (5.3 × 10−5 M) among the three COX-2 inhibitors in their experiments. From these data, Cox-2 inhibition might not directly contribute to the in vivo tumour growth inhibitory effect and reversal EMT effect in human bladder cancer cells that we used here.