CONTRASTIVE STUDY OF THE TISSUE EXPRESSION AND SERUM CONCENTRATION OF PEPSINOGEN C IN GASTRIC MUCOSA DISEASES

Objective： To estimate the practical values of pepsinogen C （PGC） dynamic expression and the levels of serum pepsinogens in gastric cancer screening and diagnosis. Methods： 129 cases gastric mucosa biopsies and serum specimens were examined. The expression of PGC in stomach mucosa was detected by immunohistochemistry. The serum concentration of pepsinogen A （sPGA） and pepsinogen C （sPGC） were determined by ELISA. Results： The positive rate of PGC antigen expression decreased in superficial gastritis （100%）, gastric ulcer or erosion （80.00%）, atrophic gastritis （34.48%） and gastric cancer （11.43%） in sequence （P〈0.05）. There was no statistics difference in concentration of sPGA and sPGC among the above 4 groups. The ratio of sPGA/sPGC decreased in superficial gastritis, gastric ulcer or erosion, atrophic gastritis and gastric cancer in sequence （P〈0.05）. There was specific correlation between the expression of PGC in stomach mucosa and the levels of sPGA/sPGC ratio in serum （rs =0.297, P=0.001）. Conclusion： Tissue expression of PGC has close relationship with different gastric diseases. The ratio of sPGA/sPGC is relative with the tissue expression of PGC antigen and may be a convenient and economic maker in screening and diagnosis of gastric cancer.     

PGC基因插入／缺失多态对胃粘膜及血清PGC蛋白表达的影响

背景与目的：胃蛋白酶原C（pepsinogenC，PGC）是胃粘膜特异性功能酶的前体，PGC基因插入／缺失多态与胃癌易感性相关。本研究旨在探讨PGC基因多态与PGC蛋白表达的关系。方法：常规酚．氯仿法提取浅表性胃炎（superficial gastritis，SG）、胃糜烂溃疡（gastric ulcer，GEU）、萎缩性胃炎（atrophic gastritis，AG）及胃癌（gastric cancer，GC）患者共493例血凝块基因组DNA。PCR法扩增PGC基因7-8外显子间的100bp插入／缺失片段，检测PGC基因多态型．多态片段用测序证实。免疫组织化学方法检测胃粘膜PGC蛋白表达水平。ELISA法检测血清PGC蛋白含量。结果：从SG→GEu→GA→GC：PGC等位基因1纯合型分布频率逐渐升高，GC组显著高于SG组（P=0．018）：胃粘膜PGC蛋白阳性率依次显著降低（均P〈0．01），强阳性率逐渐降低，除sG组与GEU组外，其余各组间差异均有统计学意义（P〈0．05）；血清PGC蛋白含量GEU组和GC组显著高于SG组（P=0．000，P=0．000）。PGC基因1纯合型与胃粘膜PGC蛋白表达强度呈负相关（r=-0．1085，P=0．023），与PGC血清含量无相关性（P=0．435）。从等位基因1纯合型→等位基因1杂合型→其它型：PGC阳性率逐渐升高，等位基因1纯合型组与其它型之间的差异有统计学意义（P=0．009）：SG组PGC等位基因1纯合型的PGC强阳性率低于其它型组（P=0．047）。结论：PGC基因多态与胃粘膜PGC蛋白表达呈负相关，与血清PGC含量无相关性。     

p16INK4a和Ki67在胃癌及癌前病变中的表达和意义

目的:探讨p16INK4a、Ki67在慢性胃炎、胃上皮内瘤变、胃癌及癌旁非肿瘤性胃黏膜中的表达和临床意义。方法:采用免疫组织化学SP法检测23例慢性胃炎、16例胃低级别上皮内瘤变、16例胃高级别上皮内瘤变、45例胃癌及癌旁非肿瘤性胃黏膜组织样本中p16INK4a、Ki67的表达。结果:p16INK4a在慢性胃炎、低级别上皮内瘤变、高级别上皮内瘤变和胃癌细胞中均呈核浆型表达,阳性表达率分别为4.34%、25.00%、62.50%、66.67%,在癌旁非肿瘤性胃黏膜腺体上皮细胞中呈阴性表达;Ki67在慢性胃炎、低级别上皮内瘤变、高级别上皮内瘤变和胃癌组织细胞中呈核型表达,Ki67指数分别为17.39%、37.50%、56.25%和77.78%。结论:p16INK4a代偿性高表达是胃癌和胃癌前病变的重要免疫表型特征,联合检测p16INK4a和Ki67表达可作为胃癌诊断的分子靶标和可靠方法。     

1A6/DRIM 表达及血清 MG7- Ag 含量在胃癌早期诊断中的价值

目的：对不同类型胃黏膜活检组织1A6/ DRIM 表达和血清 MG7- Ag 检测,探讨两者的相关性及胃癌前病变风险预测的临床应用价值。方法：131例胃黏膜活检组织及其血清标本（浅表性胃炎30例,胃黏膜糜烂溃疡26例,萎缩性胃炎伴肠上皮化生21例,胃癌54例）,采用酶联免疫吸附实验（ELISA）检测血清 MG7- Ag 含量;免疫组化 SP 法检测胃黏膜组织标本中1A6/ DRIM 的表达水平。结果：从浅表性胃炎、胃黏膜糜烂溃疡、萎缩性胃炎伴肠上皮化生到胃癌,血清 MG7- Ag 含量呈逐渐升高趋势,并且各组间比较差异均有显著性（P ﹤0.05）,胃癌患者血清 MG7- Ag 含量明显高于其他胃病患者,差异有显著性（P ﹤0.01）。1A6/ DRIM在54例胃癌组织中阳性表达34例（63.0%）,在其他胃病患者中阳性表达9例（11.7%）,差异有显著性（P ﹤0.05）。随着病变组织中1A6/ DRIM 表达的上升,血清 MG7- Ag 含量有上升趋势,两者具有良好的相关性（rs=0.346,P =0.001）。血清 MG7- Ag 和1A6/ DRIM 组织表达水平与胃癌分化程度呈负相关,二者有良好的相关性。结论：MG7- Ag 可以作为胃癌的血清学检测指标,对早期胃癌进行筛查,结合组织学1A6/ DRIM 基因表达的检查,有助于胃癌高危个体的筛查和诊断,提高胃癌早期诊断水平。     

近端胃腺癌中DKK-1和β-catenin的表达及其相关性

  目的   探讨DKK-1和β-catenin蛋白表达在胃近端癌发生过程中的作用。   方法   采用免疫组织化学S-P方法分别检测61例胃近端癌、癌旁组织及20例正常胃黏膜组织的DKK-1和β-catenin蛋白表达,并分析其临床意义。   结果   胃近端癌中DKK-1阳性表达率和β-catenin异常表达率分别为34.4%（21/61）和68.9%（42/61）,癌旁组织中DKK-1阳性表达率和β-catenin异常表达率分别为8.2%（5/61）和6.6%（4/61）,正常组织中DKK-1阳性表达率和β-catenin异常表达率分别为15.0%（3/20）和10.0%（2/20）。胃近端癌的表达明显高于其他两者（P < 0.05）,胃近端癌中DKK-1和β-catenin的表达呈正相关（r=0.454,P < 0.05）,而在癌旁组织及正常胃黏膜中的表达无明确相关性。   结论  DKK-1高表达和β-catenin异常表达上升与胃近端癌的发生密切相关。      

IL-8基因在胃癌及癌前状态中的表达

目的：探讨IL－8基因与癌前状态与胃癌发生发展的关系。方法：采用RT－PCR检测25例胃癌及癌旁正常粘膜中IL－8基因mRNA表达；免疫组化技术检测283例不同胃粘膜标本IL－8蛋白表达，其中包括29例正常胃粘膜、54例浅表性胃炎、33例胃溃疡、57例萎缩性胃炎、40例异型增生、70例胃癌。结果：1）胃癌组织中IL－8 mRNA及蛋白水平显著高于正常胃粘膜（P＜0．01）；2）正常胃粘膜、癌前状态与胃癌组织IL－8蛋白阳性表达率逐渐升高（P＜0．01），胃癌IL－8蛋白阳性表达率与癌前状态相比有显著性差异（P＜0．01）；3）浅表性胃炎、胃溃疡、异型增生、萎缩性胃炎及胃癌IL－8蛋白阳性表达率依次上升（29．6％、45．5％、57．5％、71．9％、88．6％），胃癌与萎缩性胃炎相比有显著性差异（P＜0．05）；胃癌与浅表性胃炎、胃溃疡、异型增生相比差异非常显著（P＜0．01）；萎缩性胃炎与异型增生中IL－8蛋白阳性表达率均高于浅表性胃炎（P＜0．01或P＜0．05）；萎缩性胃炎中IL－8蛋白阳性表达率高于异型增生。结论：IL－8基因在癌前状态及胃癌中高表达，IL－8基因表达增强与胃癌的发生发展及分化程度密切相关并与癌前状态的进展有关。IL－8在肿瘤中的作用机制以及临床应用前景有待于进一步研究。     

Re-expression of sonic hedgehog and reduction of CDX2 after Helicobacter pylori eradication prior to incomplete intestinal metaplasia

Loss of Sonic Hedgehog (Shh) and aberrant CDX2 expression are early changes correlating with the presence of intestinal metaplasia that occur in the gastric mucosa prior to neoplastic transformation. The aim of this study was to compare the improvement in corpus gastritis with Shh and CDX2 expression after H. pylori eradication between subjects at high risk for gastric cancer and controls. The usefulness of serum pepsinogen levels as a predictor of resolved corpus gastritis was also examined. Seventy patients with endoscopic resection for early gastric cancer and 30 controls were studied. Expression of Shh and CDX2 were evaluated by immunostaining. Serum levels of pepsinogen I before eradication in the patients scored as having improvement of corpus atrophy were significantly higher than in the patients without improvement (<0.01). Residual inflammation at the corpus lesser curve was more frequently detected in the cancer group than in the controls (OR 4.6 95% C.I. 1.6-13.5) and in the mucosa with incomplete intestinal metaplasia rather than in those without incomplete intestinal metaplasia (OR 7.6 95% C.I. 2.4-24.3). Atrophy, expression of Shh and CDX2 at the corpus lesser curve significantly improved in mucosa without incomplete intestinal metaplasia (p < 0.01), but not in mucosa with incomplete intestinal metaplasia. In conclusion, H. pylori eradication prior to development of incomplete intestinal metaplasia improves corpus gastritis and may prevent gastric cancer. Pepsinogen I may be a useful marker in patients with a residual higher risk of gastric cancer after H. pylori eradication.     

Low vitamin B12 increases risk of gastric cancer: A prospective study of one‐carbon metabolism nutrients and risk of upper gastrointestinal tract cancer

Previous studies have found associations between one‐carbon metabolism nutrients and risk of several cancers, but little is known regarding upper gastrointestinal tract (UGI) cancer. We analyzed prediagnostic serum concentrations of several one‐carbon metabolism nutrients (vitamin B12, folate, vitamin B6, riboflavin and homocysteine) in a nested case–control study within the Alpha‐Tocopherol, Beta‐Carotene Cancer Prevention (ATBC) Study of male smokers, which was undertaken in Finland between 1985 and 1988. We conducted a nested case–control study including 127 noncardia gastric adenocarcinoma (NCGA), 41 esophagogastric junctional adenocarcinoma and 60 esophageal squamous cell carcinoma incident cases identified within ATBC. Controls were matched to cases on age, date of serum collection and follow‐up time. One‐carbon nutrient concentrations were measured in fasting serum samples collected at baseline (up to 17 years prior to cancer diagnosis). Odds ratios and 95% confidence intervals (CI) were calculated using conditional logistic regression. Lower prediagnostic vitamin B12 concentrations at baseline were associated with a 5.8‐fold increased risk of NCGA (95% CI = 2.7–12.6 for lowest compared to highest quartile, p‐trend <0.001). This association remained in participants who developed cancer more than 10 years after blood collection, and after restricting the analysis to participants with clinically normal serum vitamin B12 (>300 pmol/L). In contrast, pepsinogen I, a known serologic marker of gastric atrophy, was not associated with NCGA in this population. As vitamin B12 absorption requires intact gastric mucosa to produce acid and intrinsic factor, our findings suggest vitamin B12 as a possible serologic marker for the atrophic gastritis that precedes NCGA, one more strongly associated with subsequent NCGA than pepsinogen.     

血清MG7-Ag与PG联合检测对胃癌早期诊断的临床应用价值

目的：探讨联合检测血清中MG7-Ag和胃蛋白酶原（PG）对胃癌早期诊断的临床价值。方法：采用酶联免疫吸附实验（ELISA）检测血清胃癌相关抗原MG7，胃蛋白酶原A和C含量，分析三种指标对胃癌早期诊断的临床应用价值及与胃癌临床生物学行为的关系。结果：sMG7Ag含量从浅表性胃炎、胃粘膜糜烂溃疡、萎缩性胃炎／异型增生到胃癌组有升高趋势，各组间比较统计学上均有极显著性差异（P〈0．01）；胃癌组sMG7Ag含量最高。sPGA含量从浅表性胃炎、胃粘膜糜烂溃疡、萎缩性胃炎／异型增生到胃癌组依次降低，sPGC浓度从浅表性胃炎、胃粘膜糜烂溃疡、萎缩性胃炎／异型增生到胃癌组有升高趋势，但各组间比较均无显著性差异（P〉0．05）；各组sPGA／sPGC比值依次下降，浅表性胃炎组与胃癌组比较统计学有极显著差异（P〈0．01），与萎缩性胃炎／异型增生组相比有显著差异（P〈0．05）。胃癌患者血清MG7-Ag、PGA、PGC的阳性表达率分别为51．61％，32．26％，64．52％；联合检测阳性率MG7-Ag＋PGA=70．97％，MG7-Ag＋PGC=87．10％．PGA＋PGC：70．97％，MG7-Ag＋PGA＋PGC=93．55％（P〈0．05）。结论：血清MG7-Ag、PGA、PGC对胃癌诊断有特异性，可作为胃癌早期诊断的有效指标，也可作为监测病情、判定疗效之用。     

Rsf-1在胃癌和癌前病变组织中的表达及临床意义

目的:染色质重塑因子1(chromatin remodeling factor 1,Rsf-1)可作为肿瘤靶向治疗的靶点,因此探讨其在胃癌(gastric cancer)及癌前病变(precancerous lesions)组织中的表达及临床意义。方法:采用免疫组化SP法检测30例萎缩性胃炎、30例肠上皮化生、22例不典型增生Rsf-1蛋白表达水平。并检测64例胃癌与配对癌旁组织(手术切缘距离肿瘤>5 cm)中Rsf-1和p53蛋白表达水平并分别分析与胃癌临床病理参数间的关系,同时分析Rsf-1与p53在胃癌中表达的相关性。结果:Rsf-1在胃癌、肠上皮化生、不典型增生组织中的阳性表达率均高于癌旁组织(P＜0.05)。Rsf-1在胃癌中表达与淋巴结转移有关(P＜0.05）。p53在胃癌中的阳性表达率高于癌旁组织,其表达与淋巴结转移有关(P＜0.05)。p53和Rsf-1在胃癌中的表达存在正相关性(r=0.38,P＜0.05),两者在胃癌中共阳性表达与淋巴结转移有关（P＜0.05)。结论:Rsf-1可能参与了胃癌病变的发生及发展,对胃癌早期筛查具有重要指导意义。Rsf-1和p53两者共阳性表达对于预测胃癌淋巴结转移可能具有一定的参考价值。     

Severe atrophic gastritis with Helicobacter pylori infection and gastric cancer

Background. We conducted a case-control study to evaluate whether patients with severe gastric atrophy (indicated by serum pepsinogen concentration) have a high risk of gastric cancer. Methods. At the time of diagnosis of gastric cancer, sera from 301 patients (cases) and 602 sex- and age-matched cancer-free individuals (controls) were tested for the presence of anti-Helicobacter pylori IgG antibody (HM-CAP enzyme-linked immunoassay [ELISA] kit; Kyowa Medix, Tokyo, Japan) and serum pepsinogen (PG) levels (PG I and II Riabead Kits; Dainabot, Tokyo, Japan). We defined positivity for pepsinogen a pepsinogen I concentration of less than 70 ng/mL and a PG I/II ratio of less than 3.0. We categorized the subjects according to serum pepsinogen levels and anti-Helicobacter pylori IgG antibody, creating four categories. Results. Of the 301 cancer cases, 177 had positive serum pepsinogen levels, and 172 were positive for anti-Helicobacter pylori IgG antibody. The category in which subjects had positive serum pepsinogen levels and were negative for anti-Helicobacter pylori IgG antibody had the highest proportion (76.9%) of individuals with gastric cancer and the highest odds ratio (4.20) of the four categories. The odds ratios were 2.55 (95% confidence interval; 1.92–3.88) for positive serum pepsinogen levels and 0.93 (95% confidence interval; 0.63–1.27) for positive anti-Helicobacter pylori IgG antibody. Conclusion. These results suggest that patients with positive serum pepsinogen levels who are negative for IgG antibody to Helicobacter pylori, constitute a high-risk group for gastric cancer. Helicobacter pylori infection is associated with the development of gastric cancer by providing a suitable environment i.e., severe gastric atrophy, for carcinogenesis of the gastric mucosa. Received for publication on Mar. 20, 1998; accepted on Aug. 20, 1998     

Preventive effects of etodolac,a selective cyclooxygenase‐2 inhibitor,on cancer development in extensive metaplastic gastritis,a Helicobacter pylori‐negative precancerous lesion

The present study investigated the preventive effects of etodolac, a selective cyclo‐oxygenase (COX)‐2 inhibitor, on metachronous cancer development after endoscopic resection of early gastric cancer. Among 267 early gastric cancer patients who underwent endoscopic resection, 47 patients with extensive metaplastic gastritis were selected based on endoscopic findings and our previously described criteria of serum pepsinogen (PG) test‐positive and Helicobacter pylori antibody‐negative conditions. Nonrandomized etodolac treatment (300 mg/day) was administered to 26 patients (Group A), while the remaining 21 patients were untreated (Group B). No significant differences in age, sex distribution, lifestyle factors or extent of metaplastic gastritis at baseline were identified between groups. Patients were followed for metachronous cancer development with endoscopy every 6–12 months for up to 5 years. Mean (standard deviation) follow‐up period was 4.2 (0.9) years. In Group B, 5 cancers developed (incidence rate = 6,266/100,000 person‐years), significantly more than the 1 cancer in Group A (incidence rate = 898/100,000 person‐years; p < 0.05). Long‐term etodolac treatment did not influence the extent of metaplastic gastritis as revealed by endoscopic findings or by serum PG levels, but effectively reduced metachronous cancer development in patients with extensive metaplastic gastritis. These results strongly suggest that chemoprevention of cancer in the metaplastic stomach is possible by controlling COX‐2 expression.     

Pepsinogen A,pepsinogen C,and gastrin as markers of atrophic chronic gastritis in European dyspeptics

Serum levels of pepsinogen and gastrin are parameters that can be used as biomarkers for gastric mucosa. The aim of this study was to validate these serum biomarkers, that is pepsinogen A (PGA), pepsinogen C (PGC), PGA/PGC ratio, and gastrin, as screening tests for precancerous lesions: atrophic chronic gastritis (ACG) or Helicobacter pylori-related corpus-predominant or multifocal atrophy. The study population was comprised of a subsample of 284 patients from the 451 included in the Eurohepygast cohort, between 1995 and 1997. The concentrations of PGA, PGC, and gastrin were measured by radioimmunoassays. Histological diagnosis was the gold standard. Cut-off points were calculated using receiving operator characteristics (ROC) curves. Factors linked to variation of biomarkers were identified using multivariate linear regression. The mean of each biomarker in the sample was: PGA, 77.4 microg x l(-1); PGC, 13.2 microg x l(-1); PGA/PGC, 6.7; and gastrin, 62.4 ng x l(-1). For ACG patients, the areas under the PGA, PGC, PGA/PGC, and gastrin ROC curves were 0.55, 0.62, 0.73, and 0.58, respectively. The best cut-off point for PGA/PGC was 5.6, with sensitivity 65% and specificity 77.9%. For H. pylori-related corpus-predominant or multifocal atrophy, the areas under the respective ROC curves were 0.57, 0.67, 0.84, and 0.69. The best cut-off point for PGA/PGC was 4.7, with sensitivity 77.1% and specificity 87.4%. The results suggested that only the PGA/PGC ratio can be considered as a biomarker for precancerous lesions of the stomach, and may be useful as a screening test.     

SOD在Hp感染阳性的胃癌、胃粘膜不典型增生及慢性胃炎中表达的研究

目的　观察 SOD在 Hp感染与胃癌、胃粘膜不典型增生及慢性胃炎之间所起的作用。方法　采用免疫组织化学方法观察 SOD在 Hp感染阳性胃癌、胃粘膜不典型增生及慢性胃炎组织中的表达。结果　 Hp感染的阳性胃癌、胃粘膜不典型增生及慢性胃炎组织中的 SOD表达无变化。而在胃癌、胃粘膜不典型增生及慢性胃炎三者之间 SOD的表达有差异。结论　胃癌、胃粘膜不典型增生及慢性胃炎组织中 SOD的表达不受 Hp感染的影响。监测胃粘膜中 SOD的变化 ,可为早期诊断胃癌提供帮助     

胃癌发生过程中端粒酶活性测定及临床意义

目的:通过检测胃癌及癌前病 变组织中端粒酶活性,探讨其在胃癌发 生发展中的作用及临床意义。方法:采 用SP免疫组化法检测40例胃癌和18 例癌前病变(其中慢性萎缩性胃炎伴肠 化生10例,非典型增生8例)端粒酶活 性。结果:胃癌及癌前病变中端粒酶阳 性率分别为92.5%(37/40)和33.3% (6/18),两者比较差异有统计学意义, P<0.05。端粒酶激活与胃癌的分化 程度、病理分期和淋巴结转移无明显相 关性,P>0.05。结论:端粒酶活性表 达与胃癌的发生密切相关,利用免疫组 化检测端粒酶活性可作为胃癌早期诊 断的参考指标,并应对阳性病例进行跟 踪随访。     

The role of gastric mucosal dysplasia in the development of Gastric Carcinoma

It is widely acknowledged that most stomach carcinomas developed from dysplastic lesions of gastric mucosa. They can be found in known precancerous conditions as chronic gastritis, gastric adenoma, giant rugal hypertrophy, chronic peptic ulcer, gastric stump after partial resection and pernicious anemia. Several grading systems of gastric dysplasia have been suggested. Nagayo’s or the ISGGC classification was applied to 367 biopsy specimens of 258 patients between 1979–1995. The frequency of moderate and severe dysplasia was 0,84% regarding all gastric endoscopies in the same period of time. Follow-up studies were performed in 56 cases in a period of 1–7 ys. In this group cancer developed during 14 patients. The authors’ recommendation is to follow up the patients gastric dysplasia for least 10 ys after with diagnosis. In memoriam dr. Albert I FIGUS     

Antigen MG7 in gastric cancer and gastric precancerous lesions

Earlydetectionandearlydiagnosisofgastriccancerareessentialtodecreasethemortalityandincreasesurvivalrateofgastriccancer.TheZhuangheregioninLiaoningProvinceisahighriskareaofgastriccancerandanimportantresearchbaseforgastriccancerpreventionandtreatmentinChina[1].AlargescalescreeningofgastriccancerinthisareawascarriedoutbytheCancerInstituteofChinaMedicalUniversitypreviously.Inthepresentstudy,thegastricmucosasamplesfromthescreeningwereusedtoinvestigatethedynamicexpressionofgastriccancer-associat…     

慢性萎缩性胃炎伴肠化生与胃癌ras基因表达的比较

目的：探讨胃癌发生发展不同阶段癌基因表达特点并予以定量分析，对阐明胃癌发生发展机理及早期诊断胃癌具有重要意义。方法：应用ras基因产物共有多肽序列单克隆抗体PAP免疫组化对照研究了13例慢性萎缩性胃炎伴肠化生（大肠型），32例胃窦癌及15例正常胃窦粘膜ras基因表达特点。结果：慢性萎缩性胃炎伴肠化生粘膜ras基因产物免疫反应阳性细胞形态较规则，呈卵圆形或低柱状，免疫反应强度及阳性细胞数量均较胃癌增强（多）（P均＜0．05）阳性细胞成片分布肠化粘膜下部及基底部，不穿越基底层；胃癌中免疫反应阳性细胞形态不规则，核分裂相明显，成团或散在分布，免疫反应强弱不等，呈异质性表达。正常胃窦粘膜可见谈棕黄色单个分布的ras产物阳性细胞。结论：ras基因在胃癌前病变慢性萎缩性胃炎伴肠化生中已激活，对ras产物精确定量分析有助于胃癌前病变的诊断。     

S100 A6蛋白在胃癌组织中的表达及生物学意义

目的：探讨钙结合蛋白S100A6在胃癌组织中的表达及生物学意义。方法：用组织微阵列技术构建包含51例胃癌、15例慢性萎缩性胃炎、15例正常胃黏膜组织的81点阵的石蜡组织芯片。免疫组化SP 法检测该芯片中S100A6蛋白的表达并测定其灰度值,分析其与胃癌的关系。结果：51例胃癌组织中,S100A6蛋白阳性表达率为80．4％（41／51）,平均灰度值为125．84±13．05;15例正常胃黏膜组织中未见表达;15例慢性萎缩性胃炎中阳性率为20．0％（3／15）,平均灰度值为115．86±3．00。胃癌组与正常胃黏膜组比较,P ＝0．001;胃癌组与慢性萎缩性胃炎组比较,P＝0．049;正常胃黏膜组与慢性萎缩性胃炎组比较,P＝0．14。S100A6蛋白的表达与年龄、性别及肿瘤组织分级、分期无明显关系。结论：S100A6蛋白与胃癌相关,可能与胃癌的发生及发展有密切关系。     

胃癌及癌前病变中MGMT的表达及其意义

目的:探讨DNA损伤修复基因产物-MGMT在胃癌及癌前病变中的表达及其意义。方法:采用免疫组化SP法检测MGMT在62例胃癌和42例胃黏膜异型增生组织中的表达。结果:MGMT蛋白在正常胃黏膜、轻度异型增生胃黏膜、中重度异型增生胃黏膜、早期胃癌、进展期胃癌中的阳性表达率分别为93.8%、94.4%、91.7%、66.7%、68.2%。MGMT蛋白在轻度异型增生胃黏膜的表达率明显高于早期胃癌及进展期胃癌(P<0.05);在中重度异型增生组中的表达率高于早期胃癌(P<0.05)。胃癌中MGMT表达与分化程度、淋巴结转移相关(P<0.05)。结论:MGMT基因可能在胃癌发生中起重要的作用,可能成为监测胃黏膜早期癌变及判断胃癌生物学行为的有用指标。