Study On The Expression Of Lipoxygenase In Gastric Carcinoma

Objective: To detect the expression of 5-lipoxygenase (5-LOX),15-lipoxygenase-1(15-LOX-1) and p-Akt in pairs of gastric carcinoma and adjacent normal tissues obtained by surgery, and to investigate the relationship between the expression of 15-LOX-1 and clinical pathological characters.Methods: Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of 5-LOX mRNA and 15-LOX-1 mRNA. The 15-LOX-1 protein level was detected by immunohistochemistry in 45 pairs of gastric carcinoma and adjacent normal tissue. Western blot was conducted to evaluate 5-LOX,p-Akt and 15-LOX-1 proteins in 30 pairs of fresh gastric carcinoma tissue and adjacent normal tissue.Results:(1)In gastric carcinoma, the expression of 5-LOX was significantly higher than that in the adjacent normal tissue both in mRNA level(76.7%vs40%,P<0.05) and protein level(56.7%vs 30%,P<0.05).The expression of p-Akt protein was higher than that in the adjacent normal tissue significantly(56.7%vs26.7%,P<0.05).There was no significant correlation between the expression of 5-LOX and p-Akt protein(r=0.186,P>0.05). (2)The expression of 15-LOX-1 mRNA and protein in gastric carcinoma was lower than that in the adjacent normal tissue significantly(P<0.05). There was significantly negative correlation between 15-LOX-1 protein expression and clinical pathological characters such as tumor size,lymph node metastasis and TNM stage(P<0.05).(3)In gastric carcinoma,no significant correlation was observed between 5-LOX and 15-LOX-1(P>0.05). Conclusion:(1) Over-expression of 5-LOX is observed in gastric carcinoma.It shows that the 5-LOX protein may promote the genesis and progress of gastric carcinoma, which does not associate with PI3-K/Akt signaling pathway.(2) The 15-LOX-1 protein may restrain the genesis and progress of gastric carcinoma.The assay of 15-LOX-1 expression in gastric carcinoma may be helpful to evaluate the prognosis of the patients with gastric carcinoma.(3)In gastric carcinoma,the expression of 5-LOX and 15-LOX-1 lose their balance,whereas there was no close correlation between them.