幽门螺杆菌、高胃泌素血症对结肠腺瘤形成的作用

Effects of Helicobacter pylori infection and hypergastrinemia on the growth of colonic adenoma

目的:探讨幽门螺杆菌(H.pylori)感染、血清胃泌素(GAS)与结肠腺瘤的相互关系.方法:采用放射免疫法(RIA)测定结肠腺瘤(n=48)及对照组(n=43)的血清胃泌素水平,用ELISA法检测H.pyloriIgG抗体.给予结肠腺瘤患者口服塞来昔布6mo,分别在2、4、6mo检测血清胃泌素及抗H.pyloriIgG抗体.结果:腺瘤组患者H.pylori感染阳性率、血清胃泌素水平明显高于对照组(P<0.05),结肠腺瘤组血清胃泌素水平与H.pyloriIgG抗体显著相关(r=0.854,P<0.001);远端结肠腺瘤患者H.pylori阳性率显著高于近端结肠(P<0.05),同时高胃泌素血症患者比例明显高于近端结肠(72.7%vs37.8%,P<0.05).口服塞来昔布后,H.pylori阳性率、血清胃泌素水平均趋向下降并且随着服药时间的延长进一步降低.结论:H.pylori感染可诱导高胃泌素血症与结肠腺瘤形成;COX-2可能介导胃泌素诱导的结肠腺瘤形成;口服COX-2抑制剂塞来昔布可以降低H.pylori阳性率及血清胃泌素水平,从而发挥抑制结肠腺瘤生长的作用.

AIM：To investigate the association among gastrin level,Helicobacter pylori （H.pylori） infection and the development of colonic adenoma.METHODS：Fasting serum samples from 48 patients with colonic adenomas and 43 demographically matched colonoscopy-negative controls were assayed for anti-H.pylori IgG and serum gastrin levels. Colonic adenoma patients receivedoral celecoxib for 6 months. At the end of the second,fourth and sixth months,serum gastrin levels were measured by radioimmunoassay （RIA） and H.pylori IgG antibody was analyzed by enzyme-linked immunosorbent assay （ELISA）. RESULTS：The prevalence of H.pylori seroposi-tivity was significantly higher in patients with colonic adenomas than in controls （68.8% vs 9.30%,P 0.05）. Similarly,median gastrin level was signif icantly higher in patients with colonic adenomas than in controls （72.7% vs 37.8%,P 0.05）. There was a positive correlation between H.pylori IgG antibody and serum gastrin level in colonic adenoma patients （r = 0.854,P 0.001）. Of note,hypergastrinemia was associated with distal colon distribution of adenomas,but not with adenoma number,size,grade or histologi-cal features. After celecoxib treatment,there were parallel falls in serum gastrin levels and H.pylori seropositivity in colonic adenoma patients. CONCLUSION：Hypergastrinemia induced by H.pylori infection is associated with increased cyclooxygenase-2 （COX-2） expression in colonic adenoma,suggesting the possibility that gastrin up-regulates COX-2 expression in colonic ad-enoma. Celecoxib can obviously decrease H.pylori seropositivity and gastrin levels and inhibit the growth of colonic adenomas by down-regulating COX-2 expression.