双重染色内镜联合MG7抗原检测对早期胃癌及癌前病变的诊断意义

目的 探讨双重染色内镜联合血清MG7抗原检测在早期胃癌及癌前病变中的临床价值.方法 选取疑似早期胃癌及癌前病变者患者190例,随机分为染色内镜组(Ⅰ)(65例)、MG7抗原检测组(Ⅱ)(65例)及实验组(Ⅲ)(染色内镜联合MG7抗原检测组,60例),Ⅰ组行靛胭脂-美蓝双重染色内镜检查,Ⅱ组检测患者血清MG7抗原含量,Ⅲ组在进行靛胭脂-美蓝双重染色内镜检查的同时检测患者血清MG7抗原含量.结果 Ⅰ组早期胃癌检出率为69.23％;Ⅱ组早期胃癌检出率为71.42％;Ⅲ组早期胃癌检出率为93.33％;Ⅰ组癌前病变检出率为65.38％;Ⅱ组癌前病变检出率为60.00％;Ⅲ组癌前病变检出率为83.33％;Ⅲ组较Ⅰ,Ⅱ组的检出率均存在显著性差异(P＜0.05).结论 双重染色内镜联合血清MG7抗原检测,灵敏度高,适用于早期胃癌及癌前病变诊断.     

血清胃癌相关抗原MG7-Ag的检测对胃癌的诊断价值

胃癌是常见的消化道肿瘤,高度恶性且预后较差,早期诊断、早期治疗是提高患者生存质量、降低病死率的唯-途径.胃镜加病理活检是目前公认的最有效的胃癌检查方法,但作为普查手段费用过高且人群接受度较低.     

血清MG7-Ag的检测对胃癌诊断的研究进展

近年来随着免疫学、生物化学、分子生物学、细胞工程学和遗传工程学及其相应新技术的发展,发现了许多具有一定临床价值的肿瘤标志物。本文对胃癌相关抗原（MG7-Ag）的结构、分布、生物学特性及对胃癌的诊断价值等作一综述。     

血清MG7-Ag的检测对胃癌诊断的研究进展

近年来随着免疫学、生物化学、分子生物学、细胞工程学和遗传工程学及其相应新技术的发展,发现了许多具有一定临床价值的肿瘤标志物.本文对胃癌相关抗原(MG7-Ag)的结构、分布、生物学特性及对胃癌的诊断价值等作一综述.     

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。     

血清MG7-Ag联合G-17检测在胃癌诊断中的临床价值

目的 探讨血清胃癌相关抗原(MG7-Ag)联合胃泌素-17(G-17)检测用于诊断胃癌的临床价值.方法 选择胃癌患者60例(胃癌组),胃部良性病变患者50例(良性病变组),癌前病变患者58例(癌前病变组),同时选择同期进行体检的健康志愿者50例作为对照组.检测所有患者以及健康对照组志愿者血清中MG7-Ag以及G-17的表达含量,分析2种检测指标用于诊断胃癌的临床效能.结果良性病变组、癌前病变组以及胃癌组患者血清中MG7-Ag以及G-17的表达含量显著高于健康对照组(P<0.05).胃癌进展期患者血清中MG7-Ag和G-17的含量水平显著高于早期胃癌患者(P<0.05);淋巴结转移患者血清中MG7-Ag和G-17的含量水平显著高于淋巴结非转移胃癌患者(P<0.05).与MG7-Ag、G-17单独用于诊断胃癌相比,MG7-Ag联合G-17用于诊断胃癌的敏感性、特异性更强,且阳性预测值和阴性预测值升高,其中,MG7-Ag联合G-17的敏感性、特异性,阳性预测值和阴性预测值均比MG7-Ag检测显著升高(P<0.05).结论MG7-Ag联合G-17用于诊断胃癌的特异度高,误诊率低,可以提高诊断准确性.     

内镜色素染色对食管癌、胃癌的早期诊断价值

目的：评价和探讨内镜色素染色对食管癌、胃癌的早诊断价值。方法：对67例食管癌、胃癌可疑患者局部喷洒染剂后，观察着色情况并取材。结果：对29例可疑食管癌患者卢戈液染色不染区取材，病理示食管癌12例（原位癌2例），不典型增生9例（轻度4例，中度3例，重度2例）；单纯上皮增生伴有慢性炎症8例。美蓝染色胃癌可疑患者38例中30例（78．95％）着色区还取材，病理示胃癌11例（手术证实原位癌4例），不典型增生14例（轻度6例，中度4例，重度4例），肠化5例。结论：内镜色素染色有助于食管癌、胃癌及癌前病变的早期诊断，有助于内镜下鉴别诊断的能力，方法简单、安全、实用。     

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/异型增生到胃痛组有升高趋势,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%;联合检测刚性率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.     

胃癌单克隆抗体MG7相关抗原的初步分析

国内外研究表明应用单克隆抗体技术可能建立一种特异、敏感、快速的胃癌诊断方法。近年来,第四军医大学西京医院建立了10余株抗不同组织学类型胃癌的克隆杂交株。ABC免疫组化技术及阳性扫描研究提示该组单克隆抗体有较大的应用价值。初步研究表明:抗胃癌单克隆抗体MG_7的相关抗原可能为中性糖脂。本室应用糖脂的免疫染色技术(Immunostaining)对MG_7的相关糖脂抗原作了初步分析。     

Establishment of immuno-PCR technique for the detection of tumor associated antigen MG7-Ag on the gastric cancer cell line

The gastric cancer associated antigen MG₇-Ag was detected by means of a newly established method, termed Immuno-PCR. A McAb-recombinant DNA chimeric molecule was made which possesses bispecific binding affinity for antigen that had been immobilized on microtiter wells and the segment of the attached DNA was amplified by PCR. The antigen of gastric cancer cell line KATO III was monitored by this method. Analysis of PCR products by agarose gel electrophoresis after staining with ethidium bromide allowed as few as 20 cells to be detected readily and reproducibly. Immuno-PCR showed a 10⁴ enhancement in detection sensitivity compared with ELISA assay. When the same numbers of cells (2×10⁶/ml) were immobilized and then the serial diluted chimeric molecule was added, 3.8 × 10⁻¹⁴ moles and 3.0 × 10⁻¹¹ moles were needed to give positive results with the Immuno-PCR and ELISA assay, respectively. Therefore, Immuno-PCR could give an enomous amplification capability with good specificity, and has a sensitivity much higher than any existing techniques for antigen detection.     

Detection of circulating gastric carcinoma-associated antigen MG7-Ag in human sera using an established single determinant immuno-polymerase chain reaction technique

BACKGROUND: In 1994, a novel sensitive method termed immuno-polymerase chain reaction (PCR) for the detection of the gastric carcinoma-associated antigen MG7-Ag in the gastric carcinoma cell line KATO III was reported. Compared with the enzyme-linked immunoadsorbent assay, the single determinant immuno-PCR technique could allow for as few as 20 cells to be detected and was found to show an approximately 10,000-fold enhancement in sensitivity of the detection limit. The current study clinically evaluated the significance of serum MG7-Ag detection in gastric carcinoma patients. METHODS: The sera of patients were immobilized on wells and a specific DNA molecule, which could be amplified by PCR, was employed as a marker. The biotinylated monoclonal antibody against gastric carcinoma was added to bind the antigen immobilized on the wells. After the biotinylated antibody was bound to the antigen, free avidin was used to attach a biotinylated monoclonal antibody and biotinylated DNA molecule. The biotinylated DNA complexed with antigen-antibody-avidin was amplified by PCR and the PCR products were analyzed by agarose gel electrophoresis. In the current study this method was used to detect circulating MG7-Ag in the sera of patients with gastric carcinoma and other various malignancies. For comparison, carcinoembryonic antigen, CA 50, CA 19-9, and TAG-72 were quantitated by radioimmunoassay and immunoradiometric assay using the relevant commercial kits in the same sera samples from 86 patients with pathologically confirmed gastric carcinoma and 83 patients with relevant benign diseases of the stomach. In addition, the semiquantitative analysis of PCR products among gastric carcinoma patients with or without metastasis was performed to compare the intensity of DNA band amplification. RESULTS: Using the immuno-PCR assay, positive results were obtained in 164 of 198 patients with gastric carcinoma (82.8%). The rates of positivity in other malignancies were 17.4% for esophageal carcinoma (15 of 86 patients), 44.4% for colonic carcinoma (40 of 90 patients), 0% for liver carcinoma (none of 84 patients), 2.2% for ovarian carcinoma (1 of 45 patients), 0% for uterine carcinoma (none of 27 patients), and 6.1% for lung carcinoma (4 of 66 patients). The positive results obtained from those patients with benign diseases were: 7.7% for peptic ulcer (6 of 78 patients), 5.9% for chronic gastritis (7 of 118 patients), 3.3% for chronic colitis (2 of 60 patients), and 0.8% for healthy blood donors (2 of 236 patients). In addition, the semiquantitative analysis of PCR products showed that the intensity of DNA band amplified from the PCR products of those patients with metastasis was much higher than that of patients without metastasis or those with early stage tumors (1.94 +/- 0.03 vs. 1.28 +/- 0.02). In comparative studies of immuno-PCR and commercial assays for tumor-associated antigens the sensitivity of immuno-PCR was 81.4% and pseudopositivity was lower (8.4% vs. 7.2-12.0% with radioimmunoassay or immunoradiometric assay). CONCLUSIONS: The results of the current study demonstrate that introducing PCR into the indirect determination of tumor-associated antigen in the serum can improve the sensitivity of detection greatly. This novel assay also might be used to monitor the circulating amount of tumor-associated antigen after gastrectomy and provide information regarding recurrence or metastasis, as well as for screening elderly patients who have no indications for endoscopy and those with precancerous conditions. The application of immuno-PCR in the serologic diagnosis of carcinoma has significant advantages including ready application in the clinical setting as well as use as a potential screening tool in mass surveys of high risk populations with gastric carcinoma. (c) 2000 American Cancer Society.     

胃癌特异染色剂对早期胃癌的诊断价值

目的探讨一种胃癌特异染色剂对早期胃癌的诊断价值。方法用经20例预试验筛选而最终确定的自配核染色剂进行活体模拟染色试验。标本采自经胃镜及病理确诊的195例胃癌患者。结果胃癌组织均在15％～20％浓度染色剂中短时间（≤30s）内着色,而癌周胃黏膜组织60s及以后才开始着色,两者比较差异有统计学意义（P〈0．05）。不同病理类型的胃癌在不同浓度染色剂下显色时间有所不同。结论自配核染色剂在特定浓度、短时间内可使胃癌组织特异染色,使肉眼可区别癌周黏膜组织,有望成为一种新型的胃癌特异染色剂,用于色素内镜诊断早期胃癌。     

胃癌MG7-Ag模拟表位口服DNA疫苗的研制

目的　利用减毒鼠伤寒沙门氏菌研制胃癌MG7 Ag模拟表位的口服DNA疫苗 ,并观察其对小鼠的免疫效能及保护作用。方法　构建MG7 Ag模拟表位和通用性辅助性T细胞表位融合基因的真核表达载体。将真核表达载体转入减毒鼠伤寒沙门氏菌得到模拟表位的口服DNA疫苗。以 1× 10 8cfu疫苗菌口服免疫C5 7BL/6J小鼠 ,以携带空载体的沙门氏菌和PBS口服作为对照。以ELISA法检测小鼠血清中抗MG7 Ag抗体的滴度 ,以H TDR掺入法检测小鼠脾淋巴细胞对人工合成的MG7 Ag抗原肽刺激的增殖能力。同时 ,用表达MG7 Ag的小鼠艾氏腹水瘤细胞进行肿瘤攻击 ,观察疫苗对小鼠的保护作用。结果　口服疫苗可诱导小鼠产生MG7抗体 ,但各组小鼠脾淋巴细胞体外刺激增殖实验差异无显著性。肿瘤攻击 2周后 ,疫苗免疫组 7只小鼠中有 2只未见肿瘤形成 ,而对照组 4只小鼠则全部成瘤。结论　胃癌MG7 Ag模拟表位的口服DNA疫苗具有免疫原性 ,可以诱导小鼠产生抗肿瘤免疫 ,并具有一定保护作用     

血清胃癌相关抗原联合胸苷激酶检测在胃癌诊断中的临床价值

目的：评价血清胃癌相关抗原（MG7- Ag）联合胸苷激酶（TK1）检测对胃癌患者的临床诊断价值。方法：选取2011年9月-2013年7月期间在青岛市城阳区人民医院就诊的胃病患者130例和健康查体者30例,分别检测 MG7- Ag 和 TK1在各受试者血清中的水平。结果：胃癌组血清 MG7- Ag 和 TK1含量及阳性检出率均明显高于健康对照组和胃良性病变组（P ﹤0.01）,二者联合检测阳性率最高为75.0%。结论：血清MG7- Ag 和 TK1的联合检测对胃癌的诊断具有极高的临床价值。     

肿瘤标记物联合智能染色内镜对早期胃癌的诊断价值

目的探讨肿瘤标记物联合智能染色(I-SCAN)内镜对早期胃癌的诊断价值。方法选取2012年2月至2016年2月间四川省遂宁市第一人民医院收治的90例早期胃癌患者及50例健康体检者,测定血清中CA199及CA242水平,使用I-SCAN胃镜对受试者进行观察,对各方法的敏感性、特异性、准确度、阳性预测值和阴性预测值进行分析。结果早期胃癌组患者血清中CA199和CA242水平为(85.38±7.38)U/ml和(30.32±3.18)U/ml,均明显高于健康组的(10.73±2.01)U/ml和(3.36±1.08)U/ml,差异均有统计学意义(均P<0.05)。肿瘤标记物联合智能染色内镜对早期胃癌患者诊断敏感性、准确度、阳性预测值和阴性预测值均显著高于单独肿瘤标记物CA199、CA242或智能染色内镜检测,特异度显著低于单独检测,差异均有统计学意义(均P<0.05)。I-SCAN技术可有效对比病灶毗连区正常黏膜与病灶区血管走形及病变黏膜功能,可有效呈现其黏膜特征,有效实现多通道多颜色对比。结论早期胃癌患者采用肿瘤标记物联合智能染色内镜进行检查,可显著提高临床诊断率和准确性,具有较高的临床应用价值。