Expressions of 15-PGDH, p21, p27, p16, p53, Survivin, BCL-2, BAX, BAK and BCL-XL mRNA in SGC-7901 cells transfected by pcDNA3/15-PGDH plamids for 24 h and 48 h by reverse transcriptase polymerase chain reaction. Lane M: DNA marker; 1: SGC-7901; 2: pcDNA3 24 h group; 3: pcDNA3/15-PGDH 24 h group; 4: pcDNA3 48 h group; 5: pcDNA3/15-PGDH 48 h group. aP < 0.05, bP < 0.01 vs SGC-7901, pc DNA3 24 h and 48 h group.