胃粘膜肠化及异型增生和胃癌组织中多基因异常

目的 探讨多种基因改变在癌前病变及胃癌组织中的作用.方法 应用PCR-RFLP,PCR-SSCP,RT-PCR及免疫组化技术同时对60例肠化生,30例异型增生及52例胃癌组织中抑癌基因APC,MCC,DCC,YNZ22,p53及癌基因Ki-tas,Bcl-2多种变异形式进行检测.结果 随着肠化生粘膜向异型增生、胃癌的发展,多种基因改变的频率逐步升高,胃癌组织中APC,DCC,YNZ22,p53,Bcl-2的改变频率分别为57.7%(30/52),43.1%(22/51),51.6%(16/31),67.3%(35/52),68.6%(35/51)显著高于肠化生上述基因的改变(APC 33.3%,DCC 4.3%,YNZ22 19.4%,p5326.7%,/Bcl-2 33.3%)(P＜0.05,0.01).异型增生组织中DCC基因改变为12.5%(3/24),也显著低于胃癌组织中的改变.Ⅲ型肠化中APC及bcl-2基因蛋白表达率分别为61.1%,55.6%,p53突变及蛋白表达率为57.1%,27.8%,显著高于I,Ⅱ型肠化中APC,Bcl-2蛋白表达率(6.3%,23.8%)(P＜0.01,0.05)及p53突变及蛋白表达率(18.2%,2.4%)(P＜0.05).肠型胃癌APC,p53,Ki-ras突变率分别为52.9%;82.4%;29.4%,显著高于胃型胃癌各基因的突变(APC 18.2%;p53 45.8%;Ki-raS 3.0%)(P＜0.05).肠型胃癌APC,Ki-ras,bcl-2基因的蛋白表达率分别为76.5%;41.2%;93.8%,胃型胃癌分别为30.3%;3.0%;54.5%,两型相比差别显著(P＜0.01,0.05).APC,p53及Bcl-2基因可能是肠化生癌变及肠型胃癌的热点基因.肠化生及异型增生阶段即可检测到基因改变的累积现象,但以胃癌组织中最显著.结论 多种基因改变的累积与胃癌的发生及演进密切相关.不同类型肠化生分子改变机制不同.APC,p53及Bcl-2基因有可能成为肠型胃癌早期诊断的分子标志.     

胃癌及癌前病变p53蛋白及Ki-67抗原检测的临床意义

应用免疫组织化学法检测胃癌和癌前病变p53蛋白、Ki-67抗原的表达.结果 正常胃黏膜无p53蛋白和Ki-67抗原表达.从萎缩性胃炎、肠上皮化生、胃黏膜异型增生至胃癌,p53蛋白和Ki-67抗原阳性表达率逐渐升高.胃癌及胃黏膜异型增生p53蛋白和Ki-67抗原阳性表达率显著高于萎缩性胃炎和肠上皮化生,差异有统计学意义（P＜0.05）;胃癌与胃黏膜异型增生、萎缩性胃炎与肠上皮化生比较p53蛋白和Ki-67抗原表达差异无统计学意义（P＞0.05）.认为p53蛋白和Ki-67抗原的检测有助于胃黏膜癌变的早期诊断.     

胃癌组织中hTERT基因表达及意义

目的探讨hTERT基因在胃癌发生、发展中的作用及机制。方法采用免疫组化SP法及核酸原位杂交法检测胃黏膜肠化生、异型增生及胃癌组织中hTERT蛋白及hTERT mRNA表达情况。结果胃黏膜肠化生、异型增生及胃癌组织中hTERT蛋白及hTERTmRNA阳性表达率均显著高于正常胃黏膜（P〈0.05）。hTERT蛋白表达阳性者hTERTmRNA表达阳性率显著高于hTERT蛋白表达阴性者（P〈0.01）。结论 hTERT基因与癌前病变及胃癌的发生有关,可能是胃癌的生物学标志之一。     

端粒酶在胃癌及癌前病变组织中的表达及其意义

目的：通过检测胃癌及癌前病变组织端粒酶的活性,探讨在这些病变演化中端粒酶活性表达的规律及其意义。方法：采用端粒酶TRAP－ELISA法定量检测33例胃癌、8例胃粘膜重度异型增生、5例轻度异型增生、 胃粘膜肠上皮化生、19例慢性浅表性胃炎组织端粒酶活性。结果：由慢性浅表性胃炎→胃粘膜肠上皮化生→轻度异型增生→重度异型增生→胃癌,端粒酶阳性率逐渐增高,分别为0％、42．9％、40．0％、75．0％、84．0％。端粒酶阳性率在胃癌及重度异型增生组明显高于其它各组（P＜0．005）。慢性浅表性胃炎与肠上皮化生及轻度异型增生组比较也有显著差异（P＜0．025）,而胃癌与重度异型增生组比较差异无显著性。结论：端粒酶在胃癌的发生中可能具有重要意义。追踪端粒酶阳性的胃癌前病变患者有利于早期发现胃癌。     

胃复春对胃癌癌前病变的治疗及对p21ras、p53表达的调节作用研究

目的：研究胃复春片对胃黏膜中、重度异型增生的治疗作用及对P21^ras、P53蛋白表达的调节作用，探讨其逆转胃癌癌前病变的治疗价值及机制。方法：内镜下病理活检证实为中、重度异型增生患者共58例，随机分为胃复春治疗组32例，维酶素对照组26例。治疗前后比较临床疗效，镜下改变，病理改变及胃黏膜固定部位活检标本P21^ras、P53蛋白S-P法免疫组化染色变化情况。结果：胃复春组临床症状的总有效率81．25％，内镜下改变总有效率71．88％，病理学改变总有效率65．63％，均优于维酶素对照组(分为53．85％、46．15％、34．61％)。P21^ras、P53蛋白在中、重度异型增生组织中有过度表达，胃复春能使其表达明显减弱。结论：胃复春对胃黏膜中、重度异型增生有良好的治疗作用，能促进病变胃黏膜的逆转，并对P21^ras、P53蛋白的表达有一定的调节作用，降低癌变危险性，可用于胃癌癌前病变的治疗。     

胃黏膜癌前病变中p53、p21^ras蛋白表达与幽门螺杆菌感染的关系

目的观察幽门螺杆菌(Helicobacterpylori)感染及根除H.pylori二年后p53、p21ras在二组胃黏膜上皮细胞的表达,探讨H.pylori在胃癌发生、发展中的作用.方法应用免疫组织化学染色、尿素酶快速试验(RUT)、组织学Warthin-Starry染色.198例H.pylori感染患者,慢性胃炎86例,慢性胃炎伴肠化生67例,慢性胃炎伴异型增生45例;对照组为根除H.pylori 2年后共86例,其中慢性胃炎54例,慢性胃炎伴肠化生32例,慢性胃炎伴异型增生10例.全部病例做p53、p21ras免疫组织化学染色.结果 H.pylori感染组p53、p21 ras 阳性表达率15.7%、18.7%,明显高于H.pylori根除组2.3%、7%,差异显著(P＜0.05);慢性胃炎伴肠化病变中,p53、p21ras在H.pylori感染组阳性表达率17.9%、18.4%均高于H.pylori根除组0%、9.4%,差异显著(P＜0.05)慢性胃炎伴异型增生病变中,p53、p21 ras在H.pylori感染组阳性表达率31.1%、40%均高于H.pylori根除组20%、30.4%,差异显著(P＜0.05);H.pylori 感染组p53、p21ras在慢性胃炎,肠化生,异型增生表达水平依次增高p53、p21ras共同表达阳性37例.结论在胃黏膜癌前病变中p53、p21ras 在H.pylori感染组阳性表达率高于H.pylori根除组,差异显著(P＜0.05);在慢性胃炎,肠化生,异型增生p53、p21ras表达水平在增高;p53、p21 ras表达呈正相关;H.pylori感染在胃癌发生、发展过程中起一定作用,p53、p21ras表达可能是H.pylori致癌的作用机理之一.     

hTERT、P53在胃癌及癌前病变中的表达及相关性研究

目的探讨端粒酶逆转录酶（hTERT）基因、p53蛋白在胃癌（GC）及癌前病变中的表达及相关性。方法采用免疫组化和原位杂交方法分别检测130例GC及癌前病变组织标本中p53和hTERT mRNA的表达。结果p53蛋白在慢性表浅性胃炎（CSG）、慢性萎缩性胃炎（CAG）、非典型增生（DYS）、GC中的表达率分别为5％、25％、50％、62．5％,其中GC与CSG、CAG比较有统计学差异：hTERT mRNA在CSG、CAG、DYS及GC中的表达率分别是0、10％、30％、78．75％,GC与CSG、CAG、DYS比较有统计学差异。p53阳性的GC组织中hTERT表达均为阳性,p53阴性的GC组织中hTERT阳性表达率为66．7％。结论hTERT是一个比p53更好的恶性肿瘤标记物;p53基因突变可导致端粒酶活化,但端粒酶激活可能不完全依赖于p53基因的调控。     

胃癌及癌前病变中hTERT基因和C-mye蛋白的表达意义

目的探讨胃癌及癌前病变中端粒酶逆转录酶(hTERT)基因和c-myc蛋白的表达及相互关系.方法以41例胃癌和25例相应非癌组织为研究对象,采用免疫组化和原位杂交方法检测c-myc蛋白、hTERT蛋白和hTERTmRNA,并对各指标阳性表达率和相关性进行比较分析.结果正常胃黏膜-肠型化生-异型增生-胃癌中,c-myc蛋白的阳性率分别为0,30%,53%,59%;hTERTmRNA的阳性率为10%,39%,67%,85%;hTERT蛋白为0,30%,60%,78%.三者在异型增生、胃癌中分别与正常组相比差异有显著性,而且肠化与胃癌组比较也分别具有显著性(P＜0.05).胃癌中,c-myc和hTERT蛋白的表达在低未分化、进展期、有淋巴结转移和浸润至浆膜层的肿瘤中显著增高(P＜0.01～0.05).而hTERTmRNA的表达仅与肿瘤分期有关.肠化、异型增生和胃癌三组中,c-myc和hTERTmRNA及hTERTmRNA和蛋白间分别具有显著性正相关(rs=0.504～0.696,P＜0.05).结论c-myc和hTERT的过表达是胃癌发生中的早期事件,其表达水平随着胃癌恶性程度的增加而增加;c-myc在转录水平上激活hTERT的表达,可能是胃癌发生发展的重要阶段.     

KLF6在胃癌和癌前病变中的表达及其意义

目的:探讨KLF6(krüppel-like factor 6)在胃癌和癌前病变中的表达及其意义.方法:收集郑州大学第二附属医院手术切除32例胃癌组织及其配对的正常胃黏膜组织新鲜标本,采用RT-PCR检测组织中KLF6 mRNA的表达.同期收集20例正常胃黏膜、45例肠上皮化生、16例异型增生及30例胃癌组织存档蜡块,采用免疫组织化学SP法检测组织中KLF6蛋白的表达,并结合临床资料进行分析.结果:正常胃黏膜与Ⅲ型肠上皮化生、异型增生及胃癌组间KLF6蛋白的表达差异有统计学意义(均P<0.05);KLF6蛋白的表达与肿瘤分化程度、肿瘤大小相关,差异有统计学意义(均P<0.05).正常胃黏膜与胃癌组织KLF6 mRNA表达差异无统计学意义(P=0.357).结论:KLF6蛋白的表达异常与Ⅲ型肠化、异型增生、胃癌的发生发展密切相关,其在监测癌前病变的进展及早期胃癌的发现中有一定价值.     

p27蛋白与细胞周期蛋白D1在疣状胃炎和胃癌组织中的表达及其意义

背景：疣状胃炎是一种具有特殊形态的慢性胃炎,与胃癌可能存在一定关系,但其癌变的分子机制尚不清楚。p27蛋白与细胞周期蛋白D1（cyclin D1）的异常表达参与了胃癌的发生、发展。目的：探讨p27蛋白和cyclin D1在疣状胃炎和胃癌组织中的表达及其意义。方法：收集慢性非萎缩性胃炎、未成熟型疣状胃炎、成熟型疣状胃炎、胃癌组织标本各40例,采用免疫组化法检测p27蛋白、cyclin D1表达,并分析两者与疣状胃炎患者性别、年龄、Hp感染、肠化生、异型增生的关系。结果：未成熟型疣状胃炎组p27蛋白阳性表达率显著高于胃癌组（77．5％对45．0％,P〈0．05）,与慢性非萎缩性胃炎组相比无明显差异（P〉0．05）。成熟型疣状胃炎组p27蛋白阳性表达率显著低于慢性非萎缩性胃炎组和未成熟型疣状胃炎组（52．5％对85．0％、77．5％,P〈0．05）,与胃癌组相比无明显差异（P〉0．05）。未成熟型、成熟型疣状胃炎组cyclin D1阳性表达率均显著高于慢性非萎缩性胃炎组（40．0％、42．5％对12．5％,P〈0．05）,但均显著低于胃癌组（P〈0．05）。疣状胃炎患者p27蛋白表达与肠化生、异型增生有关（P〈0．05）,cyclin D1表达与肠化生有关（P〈0．05）;p27蛋白、cyclin D1表达与性别、年龄均无关。结论ip27蛋白、cyclin D1可能参与了疣状胃炎的发生和癌变过程。     

胃癌前组织和胃癌中hTERT、Bcl-2蛋白的表达及其相互关系

目的 探讨胃癌前组织及胃癌中人端粒酶催化亚单位(human telomerase catalytic subunit,hTERT)的表达状况及其与Bcl-2蛋白表达的关系。方法 应用免疫组织化学技术检测45例慢性胃炎和19例胃癌中hTERT和Bcl-2蛋白的表达。结果 hTERT蛋白表达率在萎缩性胃炎、肠化生、异形增生和胃癌等不同胃黏膜癌变过程中呈递增趋势;hTERT蛋白的表达率在胃癌组织中显著高于异形增生、肠化生和萎缩性胃炎组织(P<0.05);在异形增生组织中显著高于肠化生和萎缩性胃炎组织(P<0.05);在肠化生组织中显著高于萎缩性胃炎组织(P<0.05)。Bcl-2蛋白表达率在萎缩性胃炎、肠化生、异形增生和胃癌等不同胃黏膜癌变过程中呈递增趋势;Bcl-2蛋白的表达率在胃癌组织中显著高于异形增生、肠化生和萎缩性胃炎组织(P<0.05);在异形增生组织中显著高于萎缩性胃炎组织(P<0.05),亦高于肠化生,但是相差无显著性;在肠化生组织中显著高于萎缩性胃炎组织(P<0.05)。Bel-2蛋白阳性患者hTERT蛋白表达率为71.43％,Bcl-2蛋白阴性患者hTERT蛋白表达率34.44％,hTERT蛋白表达率在Bcl-2蛋白阳性患者中显著高于Bcl-2蛋白阴性患者(P<0.01)。结论 在胃癌和胃癌前病变阶段,端粒酶(telomerase)与Bcl-2均可能发挥重要作用,促进了胃癌的发生、发展;Bcl-2表达增加可能是胃     

Immunohistochemical expression of cell-cycle proteins in gastric precancerous lesions

Background: The early indicator for the subject predisposed to gastric cancer is abnormal proliferation of gastric epithelial cells, such as atrophic gastritis (AG), intestinal metaplasia (IM), and dysplasia, which have been considered as precancerous lesions of gastric cancer. To determine whether p53 protein, cyclins D1, and D3, and p27^kip1 play a role in the carcinogenesis pathway of gastric cancer, we performed an immunohistochemical study of their expression in gastric precancerous lesions. Methods: A total of 1 45 endoscopic gastric biopsy specimens of AG, IM, and gastric dysplasia were studied. These molecular markers were localized by immunohistochemistry. Results: P53 was expressed in 15% of cases with gastric dysplasia and not in the pre‐dysplastic stages of the gastric mucosa. All cases were concerning high‐grade dysplasia. Cyclin D1 protein was almost undetectable in the precancerous lesions of gastric cancer. Cyclin D3 protein overexpression was seen in 10% of biopsies with IM, and 50% of biopsies with gastric dysplasia. High expression of p27^kip1 protein was demonstrated in all cases of chronic gastritis. As atrophy, IM, and dysplasia develop, expression of p27^kip1 protein is suppressed. In total, 15% of dysplastic cases showed no expression of p27^kip1 protein. Conclusions: (i) P53 mutation must be a late event during the development of gastric cancer. (ii) Cyclin D1 protein overexpression may not play a role in the progression from normal to neoplastic gastric mucosa, while overexpression of cyclin D3 is an earlier event during gastric carcinogenesis, and its role must be further evaluated. (iii) Reduced expression of p27^kip1 is a rather early event in gastric tumorigenesis, before dysplastic changes occur.     

原位杂交方法检测胃癌及其癌前病变中抑癌基因p53的表达

目的用原位杂交方法检测胃粘膜癌前病变及胃癌组织中ｐ５３ｍＲＮＡ的表达,并观察感染Ｈｐ对其表达的影响．方法病理证实为慢性胃炎６６例和胃癌１６例,用地高辛标记的ｃＤＮＡ为探针进行原位杂交实验,检测其胃粘膜组织中ｐ５３ｍＲＮＡ表达,用单克隆抗体ＤＯ０１进行免疫组化检测Ｐ５３蛋白的表达．结果在慢性萎缩性胃炎、肠化生、异型增生及胃癌中,原位杂交方法检测ｐ５３ｍＲＮＡ表达率分别为５３９％,５２３％,４２８％和２５％,免疫组化方法检测Ｐ５３蛋白的表达率分别为００％,５３％,１５４％和２５％．ｐ５３ｍＲＮＡ的表达与蛋白的表达无明显的一致性,ｐ５３ｍＲＮＡ的表达可以在Ｐ５３蛋白阴性及阳性的细胞中．在２６例萎缩性胃炎中,１４例检测到ｐ５３ｍＲＮＡ的表达,而其中１６例（包括１４例阳性病例）无一例检测到Ｐ５３蛋白的表达．在肠化生、异型增生及胃癌组织中也发现有类似的情况．Ｈｐ感染组与未感染组,ｐ５３ｍＲＮＡ表达率之间统计学检验Ｐ＜００５．结论在胃癌及其癌前病变中,随着病变的发展,ｐ５３ｍＲＮＡ的表达率随之下降,Ｈｐ对其表达有明显的影响     

Possible involvement of leptin and leptin receptor in developing gastric adenocarcinoma

AIM: To investigate the expression of leptin and leptin receptor (ob-R) in intestinal-type gastric cancer and precancerous lesions, and to explore the possible mechanism and role of the leptin system in developing intestinal-type gastric adenocarcinoma. METHODS: Immunohistochemistry was performed to examine the expression of leptin and leptin receptor in archival samples of gastric adenocarcinoma and preneoplastic lesions, including intestinal metaplasia and mild to severe gastric epithelial dysplasia. Positive staining was identified and percentage of positive staining was graded. RESULTS: Dual expression of leptin and leptin receptor were detected in 80% (16/20) intestinal metaplasia, 86.3% (25/30) mild gastric epithelial dysplasia, 86.7% (26/30) moderate gastric epithelial dysplasia, 93.3% (28/30) severe gastric epithelial dysplasia, 91.3% (55/60) intestinal-type gastric adenocarcinoma and 30.0% (9/30) diffuse-type gastric carcinoma. The percentage of dual expression of leptin and leptin receptor in intestinal-type gastric adenocarcinoma was significantly higher than that in diffuse-type gastric adenocarcinoma (x2 = 37.022, CONCLUSION: Our results indicate the presence of an autocrine loop of leptin system in the development of intestinal-type gastric adenocarcinoma.     

Effect of Helicobacter pylori infection on Bax protein expression in patients with gastric precancerous lesions

AIM: To investigate the effect of Helicobacter pylori (H pylori) infection on Bax protein expression, and explore the role of H pylori in gastric carcinogenesis. METHODS: H pylori was assessed by rapid urease test and Warthin-Starry method, and expression of Bax protein was examined immunohistochemically in 72 patients with pre-malignant lesions. RESULTS: Bax protein was differently expressed in intestinal metaplasia and gastric dysplasia, and showed 63.99% positivity. The positivity of Bax protein expression in Hpylori-positive gastric precancerous lesions (72.3%) was significantly higher than that in H pylori-negative gastric precancerous lesions (48.0%, X~2=4.191, P<0.05). H pylori infection was well correlated with the expression of Bax protein in gastric precancerous lesions (r=0.978, P<0.01). After eradication of H pylori, the positivity of Bax protein expression significantly decreased in H pylort-positive gastric precancerous lesions (X~2=5.506, P<0.05). In the persisting H pylori-infected patients, the positivity of Bax protein expression was not changed. CONCLUSION: H pylori infection may be involved in the upregulation of Bax gene, which might be one of the mechanisms of H pylori infection-induced gastric epithelial cell apoptosis. H pylori might act as a tumor promoter in the genesis of gastric carcinoma and eradication of H pylori could inhibit gastric carcinogenesis.     

BSG President's Report for 1994-5

p53 Protein accumulation in early gastric carcinoma was studied in relation to the histological type (Lauren classification) and the type of growth pattern, including the chronology of p53 protein accumulation during carcinogenesis. Forty five, paraffin embedded gastrectomy specimens from early carcinomas were examined for the presence of chronic atrophic gastritis, subtypes of intestinal metaplasia, and dysplasia. The Lauren type and the type of growth pattern were reassessed for all early carcinomas. p53 Protein accumulation was examined using the monoclonal antibody DO-7. Complete absence of p53 protein accumulation was observed in normal gastric mucosa, chronic atrophic gastritis, and intestinal metaplasia, irrespective of subtype. In gastric dysplasia (one mild, two moderate, and one severe), only severe dysplasia was p53 positive. Intestinal type (n = 20) and diffuse type early gastric carcinomas (n = 25) were p53 positive in 70% and 52% of cases, respectively. Both tumour types differed significantly in the percentage of p53 positive tumour cells per tumour (p < 0.01) and in staining intensity (p < 0.05). No significant difference in p53 protein accumulation was found between early carcinomas with different types of growth pattern. It is concluded that p53 protein accumulation--usually reflecting missense p53 gene mutation--seems to be a late event in gastric carcinogenesis. Moreover, it is suggested that missense p53 gene mutation occurs in a final pathway common to both intestinal and diffuse type of early gastric carcinoma. Finally, the types of growth pattern do not seem to differ in p53 protein accumulation.     

胃粘膜癌变过程中幽门螺杆菌感染与p53,c-erbB-2基因表达的研究

目的探讨胃粘膜癌变过程中幽门螺杆菌（Ｈｅｌｉｃｏｂａｃｔｅｒｐｙｌｏｒｉ,Ｈｐ）感染与ｐ５３,ｃｅｒｂＢ２基因表达的关系．方法浅表性胃炎１６例,肠上皮化生２２例,异型增生１４例,早期胃癌１８例及进展期胃癌４０例作为研究对象．用ＷａｒｔｈｉｎＳｔａｒｙ银染色法检测Ｈｐ,用免疫组化Ｓｐ法检测ｐ５３和ｃｅｒｂＢ２的基因表达产物．结果Ｈｐ,ｐ５３,ｃｅｒｂＢ２在浅表性胃炎的检出率各为５００％,００％,００％;在肠上皮化生的检出率各为５９１％,２２７％,１３６％;在异型增生的检出率各为８５７％,６４３％,２８６％;在早期胃癌的检出率各为１６７％,３３３％,１１１％;在进展期胃癌的检出率各为５０％,５２５％,５５０％;在癌旁粘膜的Ｈｐ检出率为８６７％;在癌前病变中,Ｈｐ阳性组的ｐ５３,ｃｅｒｂＢ２表达率均高于Ｈｐ阴性组．结论Ｈｐ感染参与了胃癌前病变的发生与发展;Ｈｐ感染可引起野生型ｐ５３基因失活和ｃｅｒｂＢ２基因激活,从而导致胃粘膜的癌变．