胃底腺黏膜型腺癌一例报道并文献复习

目的探讨胃底腺黏膜型腺癌的临床病理学特征及免疫组化表型。 方法总结山东省立医院西院病理科确诊的1例胃底腺黏膜型腺癌的临床及病理学资料,分析其组织形态学特点及免疫组织化学染色表达,并复习相关文献。 结果老年女性,胃底大弯侧见直径2.0 cm的不规则表浅隆起,中央浅糜烂,行内镜下黏膜剥脱术,肿瘤组织镜下为中-高分化管状腺癌,伴有乳头状腺癌,免疫组化染色小凹上皮分化区域MUC5AC(＋);胃底腺分化区域MUC6(＋)、pepsinogen-I(＋);Ki-67指数约5%。 结论胃底腺黏膜型腺癌是一种新的肿瘤类型,发病率极低,既有胃底腺型腺癌的内镜和病理特征,又有小凹上皮来源腺癌的内镜和病理特征;加强该肿瘤的认识有助于对其正确诊断与治疗。     

氨基己糖和磷脂含量评价胃粘膜防御机制

目的测定大鼠胃粘膜氨基己糖和磷脂含量，以证实其对评价胃粘膜防御机制的价值．方法大鼠３６只分为５个组．Ⅰ组为正常对照组；Ⅱ组为无水乙醇损伤对照组；Ⅲ组为胶体次枸橼酸铋加无水乙醇组；Ⅳ组为硫糖铝加无水乙醇组；Ⅴ组为雷尼替丁加无水乙醇组．测定胃粘膜氨基己糖、磷脂含量以及胃粘膜血流（ＧＭＢＦ）、跨胃粘膜电位（ＰＤ）及胃粘膜表面疏水性．结果乙醇损伤大鼠胃粘膜后，氨基己糖（ｍｇ／ｇ蛋白：０２１±００３ｖｓ０５９±００４）和磷脂含量（ｍｇ／ｇ蛋白：０３２±００４ｖｓ０６４±００４）显著下降（Ｐ＜００１）．胶体次枸橼酸铋和硫糖铝可使氨基己糖及磷脂较乙醇损伤对照组显著升高（Ｐ＜００１）．胃粘膜氨基己糖及磷脂含量与ＧＭＢＦ，ＰＤ和粘膜表面疏水性呈显著正相关．结论胃粘膜氨基己糖及磷脂含量对评价胃粘膜损伤和药物疗效有重要价值．     

Calcitonin in human gastric mucosa and carcinoma

Summary The localization of immunoreactive calcitonin (IR-CT) in the human gastric mucosa and tumor tissues was studied using an immunohistochemical peroxidase-antiperoxidase method. A small number of IR-CT-containing cells were observed in both infant and adult gastric antral mucosa and the ratio of IR-CT-containing cells to G cells was about 1:50-100. Moreover, tissue content of IR-CT in normal antral mucosa was 2.37±0.35 ng/g wet weight. IR-CT-containing cells and G cells decreased with the progress of chronic atrophic gastritis and were totally absent in intestinal metaplastic glands. IR-CT was detected in G cells, suggesting a paracrine relation between gastrin and CT. IR-CT was not found in tumor cells of 35 gastric adenomas and 40 well differentiated adenocarcinomas. On the other hand, it was demonstrated in a very small number of tumor cells in 4 of 46 poorly differentiated adenocarcinomas, and in a good number in 3 of 7 scirrhous argyrophil cell carcinomas. IR-CT in plasma could serve, therefore, as a tumor marker of scirrhous endocrine cell carcinoma, and its production in cancer cells was considered to be eutopic rather than ectopic.Supported in part by Grant-in Aid for Cancer Research from the Ministry of Education, Science and Culture (No. 59010074).     

Metabolomics of gastric cancer metastasis detected by gas chromatography and mass spectrometry

AIM:To elucidate the underlying mechanisms of metastasis and to identify the metabolomic markers of gastric cancer metastasis.METHODS:Gastric tumors from metastatic and nonmetastatic groups were used in this study.Metabolites and different metabolic patterns were analyzed by gas chromatography,mass spectrometry and principal components analysis (PCA),respectively.Differentiation performance was validated by the area under the curve (AUC) of receiver operating characteristic curves.RESULTS:Twenty-nine metabolites were differentially expressed in animal models of human gastric cancer.Of the 29 metabolites,20 were up-regulated and 9 were down-regulated in metastasis group compared to non-metastasis group.PCA models from the metabolite profiles could differentiate the metastatic from the nonmetastatic specimens with an AUC value of 1.0.These metabolites were mainly involved in several metabolic pathways,including glycolysis (lactic acid,alaline),serine metabolism (serine,phosphoserine),proline metabolism (proline),glutamic acid metabolism,tricarboxylic acid cycle (succinate,malic acid),nucleotide metabolism (pyrimidine),fatty acid metabolism (docosanoic acid,and octadecanoic acid),and methylation(glycine).The serine and proline metabolisms were highlighted during the progression of metastasis.CONCLUSION:Proline and serine metabolisms play an important role in metastasis.The metabolic profiling of tumor tissue can provide new biomarkers for the treatment of gastric cancer metastasis.     

Trefoil factor 2 in gland mucous cell mucin in the mucous gel covering normal or damaged gastric mucosa using the Mongolian gerbil model

Objective. Trefoil factor 2 (TFF2) is localized in gastric gland mucous cells. The purpose of the study was to determine whether TFF2 and gastric mucin are localized in mucous cells and in the surface mucous gel layer (SMGL) of the normal gastric mucosa or in the mucoid cap adherent to gastric mucosal lesions in Mongolian gerbils. Material and methods. Gastric mucosal lesions were induced in Mongolian gerbils using oral administration of Helicobacter pylori (H. pylori), subcutaneous administration of indomethacin, or oral administration of 30% ethanol. Tissue samples were fixed in Carnoy's solution for preservation of the SMGL, dehydrated, and embedded in paraffin. Histochemical staining for gastric mucins and immunostaining for TFF2 were performed. Results. It was found that surface mucous cell mucin and gland mucous cell mucin were segregated in the SMGL covering the normal gastric mucosa, and the mucin of the mucoid cap covering the mucosal lesions was primarily gland mucous cell mucin. There was a co-localization of TFF2 in gland mucous cell mucin in gland mucous cells, the SMGL, and the mucoid cap. Conclusions. The co-localization of TFF2 in gland mucous cells and in the adherent mucus suggests a physical interaction between TFF2 and gland mucous cell mucin, and the participation of TFF2 trapped in the adherent mucus functions in mucosal defense, healing, and repair.     

Investigation of cardiac metabolism using stable isotopes and mass spectrometry

Summary The technique described in this communication enables detailed investigations of cardiac metabolism using¹³C-labeled substrates and mass spectrometric measurements of¹³CO₂ in the coronary effluent. To validate this technique for further studies isolated working rat hearts were perfused with¹³C-labeled substrates in a bicarbonate-free perfusion fluid. The fraction of CO₂ produced by oxidation of labeled substrate was calculated by the¹³CO₂/CO₂ ratio in the coronary perfusate. The oxidation of¹³C-acetate showed a linear correlation with¹³C-acetate concentrations between 0.015 and 0.16 mmol/l. An inhibitor of acylcarnitine translocase, 2-(3-methylcinnamylhydrazono)-propionate (BM42.304) decreased CO₂ production from¹³C-palmitate from 48%±4% to 31%±3% (n=11, SEM). Taking into account considerations of tracer kinetic theory rapidly accessible intracellular palmitate stores were estimated to be less than 900 nmol/g ww. This technique allows specific investigations of the oxidation of labeled substrates in the heart and may be useful for basic research and/or clinical diagnosis, thus avoiding the hazards of radiolabeled substrates.     

Rapid and specific detection of clinically significant haemoglobinopathies using electrospray mass spectrometry-mass spectrometry

Increasing demand for population screening for the haemoglobinopathies gives rise to a requirement for high throughput systems, which allow for cost effective, rapid, sensitive and specific screening of clinically significant haemoglobins. We have developed a practical and efficient approach using tryptic digestion and electrospray triple quadrupole mass spectrometry-mass spectrometry (MSMS) in multiple reaction monitoring acquisition mode for the identification of the clinically important haemoglobin variants, S, C, DPunjab, OArab, and E. A total of 200 blood samples, comprising 52 haemoglobin AA, 57 AS (sickle cell trait), 44 AC (C trait), 16 SC (SC disease), 14 SS (sickle cell disease), 10 AE (E trait), 2 ADPunjab (DPunjab trait) and 1 each of AOArab (OArab trait), CC (C disease), DPunjabDPunjab (DPunjab disease), OArabOArab (OArab disease), and EE (E disease), have been analysed in parallel with existing phenotype and molecular methods. All haemoglobin variants were correctly identified by MSMS, with no false positives or false negatives. The system detects both heterozygotes and homozygotes and has potential applications in neonatal and antenatal screening.     

MALDI mass spectrometry imaging analysis of pituitary adenomas for near-real-time tumor delineation

We present a proof of concept study designed to support the clinical development of mass spectrometry imaging (MSI) for the detection of pituitary tumors during surgery. We analyzed by matrix-assisted laser desorption/ionization (MALDI) MSI six nonpathological (NP) human pituitary glands and 45 hormone secreting and nonsecreting (NS) human pituitary adenomas. We show that the distribution of pituitary hormones such as prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), and thyroid stimulating hormone (TSH) in both normal and tumor tissues can be assessed by using this approach. The presence of most of the pituitary hormones was confirmed by using MS/MS and pseudo-MS/MS methods, and subtyping of pituitary adenomas was performed by using principal component analysis (PCA) and support vector machine (SVM). Our proof of concept study demonstrates that MALDI MSI could be used to directly detect excessive hormonal production from functional pituitary adenomas and generally classify pituitary adenomas by using statistical and machine learning analyses. The tissue characterization can be completed in fewer than 30 min and could therefore be applied for the near-real-time detection and delineation of pituitary tumors for intraoperative surgical decision-making.Pituitary adenomas are common, benign intracranial tumors arising in the anterior pituitary gland (1–3) and are the third most common primary brain tumor. These tumors are classified according to both their size—microadenomas have a diameter less than 1 cm, whereas macroadenomas have a diameter equal to or larger than 1 cm—and by their functional status. Some tumors produce supraphysiologic quantities of hormones normally secreted by the pituitary gland and are referred to as functional adenomas, whereas others do not and are termed nonfunctioning tumors. The mass effect resulting from large adenomas that have parasellar or suprasellar extension can produce headaches, diplopia, visual field defects, cranial nerve palsies, and pituitary dysfunction due to compression of the pituitary gland and surrounding brain structures (4). Hormone-secreting adenomas [for instance, those that produce excess prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), or thyroid stimulating hormone (TSH)] can generate a broad range of endocrine disturbances and comorbidities related to the specific hormone being secreted in excess (5–9).Transsphenoidal surgical approaches are the most common first-line treatment for pituitary adenomas that require surgical intervention. These procedures relieve the compression of critical structures by macroadenomas, and reduce or eliminate abnormal hormonal hypersecretion by hormone-producing adenomas (10–12). Microadenomas can be radiologically difficult or impossible to detect because of their smaller volume, but clinical presentations such as overproduction of hormones (e.g., ACTH, inducing Cushing syndrome) warrant surgical intervention. In such cases where MRI scans are equivocal, surgical planning is based on inferior petrosal sinus sampling that may help determine the side of the pituitary involved and direct the extent of surgery. Determining the extent of tumor resection even when preoperative radiologic images are available for surgical guidance can be difficult, and incomplete resection and residual tumor may result. In macroadenomas, intraoperative magnetic resonance imaging (MRI) can be used to evaluate the extent of resection (13), but access to such a resource can be limited. Fluorescence approaches can also be used to evaluate the extent of resection: Using indocyanine green (ICG) fluorescence during endoscopic endonasal transsphenoidal surgery can help differentiate adenoma from normal pituitary tissue by detecting the near-infrared light that is emitted by ICG from the microvasculature of the normal pituitary and the adjacent tumor tissue (14). The reliable discrimination of pituitary tumor from normal pituitary gland remains a central issue in the successful surgical resection of these tumors given the desire to preserve or even restore normal pituitary function in patients.Determination of serum hormone levels is an important part of the clinical evaluation of patients with pituitary adenomas. Imaging tests such as MRI and computed tomography (CT) are also used, but the resolution of such imaging technologies is limited to a scale of millimeters, so these studies may not detect very small microadenomas. The normal pituitary is composed of an anterior lobe (adenohypophysis) and a posterior lobe (neurohypophysis) with zonal distributions of various secretory cells. The adenohypophysis contains GH-producing cells located in the lateral wings, PRL-producing cells in the posterior lateral areas, TSH-producing cells in the anterior midline area, follicle stimulating hormone (FSH) or luteinizing hormone (LH)-producing cells throughout the adenohypophysis, and ACTH-producing cells in the midline area extending back into the neurohypophysis. The neurohypophysis comprises axons from neurons that originate in the hypothalamus and that secrete oxytocin and vasopressin (15). The ACTH-related pituitary hormones are processing products of a common precursor protein named pro-opiomelanocortin (POMC). Enzymatic cleavage of this prohormone produces the following peptides: signal peptide, N-terminal glycopeptide, γ-melanocyte-stimulating hormone (γ-MSH), joining peptide, ACTH, α-melanocyte-stimulating hormone (α-MSH), corticotropin-like intermediate peptide (CLIP), β-lipotropin (β-LPH), γ-lipotropin (γ-LPH), and β-endorphin (16).The development of new intraoperative techniques to analyze the distribution of specific pituitary hormones could be helpful for surgeons as they strive to better define the location and the boundaries of the pituitary adenomas, thereby improving the extent of resection and minimizing damage to normal pituitary structures. Mass spectrometry imaging (MSI) has been recognized as a powerful tool for the molecular profiling and imaging of a variety of tumors. This technique has been used for characterizing molecules such as proteins, peptides, lipids, and metabolites in tissue samples (17–24). Desorption electrospray ionization (DESI) coupled with MSI has already been shown to distinguish cancerous from noncancerous tissue, and studies validating its implementation in an operating room for real-time and near-real-time diagnosis have been presented (25–28). Matrix assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) has also shown great promise in supporting approaches already used in clinical diagnostic practice (29–32).Here, we present a proof of concept study for the analysis of pituitary adenomas by MALDI MSI for surgical application. First, we used MALDI MSI to characterize the distribution of specific hormones such as ACTH and GH in the adenohypophysis, and vasopressin and neurophysin 2 in the neurohypophysis of normal human pituitary glands. We further used MALDI MSI to characterize a series of pituitary adenomas, and confirmed the identity of these pituitary hormones by using a high-resolution sequencing approach (LIFT) and in-source decay (ISD) methods. Our study demonstrates that the hormone composition of pituitary tumor resection samples can be assessed by using MALDI MSI within the time constraints of surgical intervention. This top-down approach might support the localization of small tumors within the gland, the delineation of tumor margins in a near-real-time diagnostic platform, and aid in the improved discrimination of tumor, which is to be resected, from normal gland, which is to be preserved.     

胃粘膜组织激素与胃癌、消化性溃疡的相关性研究

目的　研究胃泌素、胃动素、生长抑素及胰高血糖素等胃肠激素在胃癌癌组织及消化性溃疡的含量变化及它们之间的相关性。方法　内镜及活检确诊的慢性浅表性胃炎 (CSG) 2 4例 ,十二指肠球部溃疡 (DU) 2 0例 ,胃溃疡 (GU) 18例 ,胃癌 (GC) 15例 ,胃镜下取胃窦粘膜及胃癌癌组织 ,用RLA法测定胃泌素、胃动素、生长抑素及胰高血糖素的含量。结果　胃癌癌组织中 ,胃泌素、胃动素及胰高血糖素的含量分别为 168 9pg/mL± 62 5pg/mL、43 5 5pg/mL± 97 1pg/mL、12 3 4pg/mL± 41 3pg/mL ,明显高于DU(87 3pg/mL± 2 0 4pg/mL、3 72 2pg/mL± 86 9pg/mL、84 8pg/mL± 2 3 6pg/mL)、GU(92 5pg/mL± 2 6 3pg/mL、3 84 6pg/mL± 78 6pg/mL、64 9pg/mL± 18 2pg/mL)、及CSG(76 9pg/mL± 3 0 6pg/mL、2 86 7pg/mL± 64 3pg/mL、3 6 7pg/mL、14 3pg/mL)组 (P <0 0 1) ,生长抑素的含量 2 8 7pg/mL± 16 3pg/mL却显著低于DU(78 4pg/mL± 3 2 3pg/mL)、GU(86 9pg/mL± 2 8 8pg/mL)及CSG(4 6 8pg/mL± 13 4pg/mL)组 (P <0 0 1)。同时亦发现上述激素在GU及DU组的含量亦明显高于CSG组 (P <0 0 1)。结论　胃泌素、胃动素、生长抑素、胰高血糖素含量的变化可能参与了胃癌的发生、发展 ,并与溃疡的形成相关。     

质谱仪在真菌鉴定中的应用与评价

目的探讨质谱仪在真菌感染中的应用,评价其鉴定真菌的能力。方法选取分离自我院住院患者的真菌菌株327株,用质谱仪进行快速鉴定,并与VITEK-2(酵母样真菌)和显微镜检查(丝状真菌)的鉴定结果进行比对,差异结果用分子生物学方法确认鉴定。结果依照质谱仪评分标准,227株酵母样真菌在种水平(2.0)的鉴定率为90.31%,在属水平(1.7)为98.68%;丝状真菌在种水平的鉴定率为74.00%,在属水平为94.00%。对临床常见的曲霉菌鉴定正确率可达96.74%。结论质谱仪在鉴定真菌的种属水平上都达到了令人满意的结果,尤其鉴定酵母菌和曲霉菌的能力更为突出,可作为临床实验室的常规检测方法。     

Gastrin receptors in the human gastrointestinal tract and pancreas

The specific binding of¹²⁵I-labeled gastrin-17 was studied in samples of human gastric mucosa, duodenal mucosa, colonic mucosa or pancreatic tissue obtained surgically. With regard to gastric fundic mucosa, the criteria for receptor binding were studied, and saturability, high affinity, tissue specificity and hormone specificity were demonstrated. The dissociation constant for gastric fundic mucosa was 1.6 x 10^-9M, and the binding capacity was 15 fmol/mg protein. Tissue specificity studies revealed a high degree of gastrin receptor binding in human gastric fundic mucosa, duodenal mucosa and pancreas, whereas antral mucosa and colonic mucosa demonstrated a low degree of binding.     

DEC205在幽门螺杆菌感染的胃黏膜中的表达

目的:探讨幽门螺杆菌(Helicobacter pylori,H.pylori)感染的胃黏膜与DEC205的关系.方法:对13名H.pylori感染阳性患者的胃黏膜进行内窥镜活检,以及对这13例中7例被根除H.pylori的患者的胃黏膜进行二次内窥镜活检,活检标本行冰冻组织切片后,分别进行DEC205抗体的免疫组织化学染色,以及进行DEC205抗体和CD14抗体的免疫荧光染色.结果:对比除菌成功H.pylori阴性的患者,H.pylori阳性患者胃小凹处的胃黏膜上皮细胞间DEC205的表达明显增多.胃黏膜中,DEC205与CD14表达在同一个位置,而且DEC205与CD14的表达在H.pylori感染胃黏膜中明显高于除菌成功的H.pylori阴性的患者.结论:胞吞受体DEC205在H.pylori感染的胃黏膜巨噬细胞中呈高表达.     

Study on the quality of recombinant proteins using matrix-assisted laser desorption ionization time of flight mass spectrometry

Subjecxtheadingsrecombinantproteins;molecularweight;flightmassspectrometry;erythroPOietintrypticdigestsINTRODUCTIONSinceHillenkampetal[ljfirstintroducedmatrixassistedlaserdesorption/ionizationtimeofflightmassspectrometry(MALDI-TOFMS)toanalyzeproteinswithmolecularmassesgreaterthanM.10000,~DI--TOFMShasbeenwidelyusedtostudydifferentclassesofbiomoleculessuchasproteins,oligonucleotides,polysaccharidesandpolymers"--".Comparedtothetraditionaltechniques,suchassodiumdodecylsulfatepolyacryl…     

胃粘膜瘦素及其受体研究进展

瘦素(leptin)是一种肥胖基因编码的、主要由白色脂肪组织分泌的蛋白类激素。瘦素及其受体广泛分布于全身各组织器官,发挥多种生物学功能。近年来研究发现胃粘膜组织中也有瘦素及其受体的表达,它们可能在胃发挥重要的病理生理作用。     

乙型肝炎患者胃粘膜中HBsAg表达分析

目的探讨乙型肝炎病毒的泛嗜性.方法采用免疫组化SP法,对45例随机采样的乙型肝炎患者行胃粘膜活检,作HBsAg检测;采用ELISA法检测静脉血HBV.结果乙型肝炎患者胃粘膜中有HBsAg存在,主要呈弥漫胞浆型分布,腺腔和胃小凹及间质中也可见HBsAg颗粒;血清中HBV单项或多项阳性者,胃粘膜HBsAg阳性率相近(75～80%);各类型乙型肝炎患者胃粘膜HBsAg阳性率比较CAH＞CPH＞HLC,但彼此之间差异不显著(P＞0.005).结论乙肝患者胃粘膜中有HBsAg存在.     

肝硬化患者胃粘膜病变与血清胃蛋白酶原水平变化

目的 探讨肝硬化合并胃黏膜病变患者血清胃蛋白酶原（PG）水平的变化情况。方法 2011年9月~2014年3月我院收治的肝硬化患者,经胃镜检查发现胃黏膜正常138例,并发胃黏膜病变156例,后者又分为糜烂性胃炎组56例、萎缩性胃炎组37例、胃溃疡组23例、十二指肠球部溃疡组22例和胃癌组18例。采用时间分辨荧光免疫分析法测定血清PG水平。结果 肝硬化合并胃黏膜病变患者血清PGI 水平、PGI/PGII比值[（78.08±21.33）μg/L,（6.75±1.81）]高于无胃粘膜病变组[（51.37±19.85） μg/L,（4.87±1.56）,差异有统计学意义（P<0.05）];两组血清PGII水平[（12.16±5.60）μg/L 对 （13.02±4.96）μg/L]比较,差异无统计学意义（P>0.05）;萎缩性胃炎组和胃癌组血清PGI水平[分别为（34.18±11.35）μg/L和（28.96±12.14）μg/L]显著低于糜烂性胃炎组[（108.28±20.87）μg/L]、胃溃疡组[（113.37±20.04）μg/L]、十二指肠球部溃疡组[（138.65±19.38）μg/L],差异有统计学意义（P<0.05）。结论 肝硬化患者血清PG水平与胃黏膜病变密切相关,不同类型胃病患者血清PG水平不同,对临床有重要的参考价值。     

质谱分析技术在儿童代谢性肝病诊断方面的应用

质谱分析技术已被公认为代谢性疾病化学诊断的有用手段，气相色谱质谱连用法可以对130余种代谢疾病进行筛查和化学诊断，串联质谱法可对30余种脂肪酸代谢异常疾患和部分氨基酸代谢异常同时筛查，作为先天性代谢疾病的新生儿筛查手段被广泛的应用在世界各国。代谢性肝病涉及不同的代谢途径的紊乱，多种儿童代谢性肝病都有疾病的特征性代谢谱存在，因此通过质谱分析的代谢组学研究将会对这类疾病的临床诊断非常有用。     

Analysis of protein expression patterns in Barrett''s esophagus using MALDI mass spectrometry, in search of malignancy biomarkers

SUMMARY: In order to detect early changes of malignant degeneration in Barrett's esophagus (BE), and to reduce the cost of surveillance, molecular biomarkers of early malignancy have been sought, with limited success, using genomic and immunohistochemical tools. We postulate that direct analysis of epithelial proteins using mass spectrometry will provide protein profiles capable of identifying patients at high risk of developing malignancy. Our aim is to find transitional protein signals that show a cancer profile within histologically benign BE, which can be used as indicators of early malignant change. Fourteen fresh-frozen, resected esophageal cancer specimens were analyzed using laser capture microdissection and matrix-assisted laser desorption/ionization mass spectrometry. Samples of squamous epithelium, and both benign and malignant Barrett's epithelium, were compared for differences in protein expression. Reliable differentiation of squamous and Barrett's epithelium was demonstrated. A comparison of benign and malignant Barrett's epithelium identified a number of cancer-specific protein peaks that were deletion or expression variations from benign epithelium. In four instances the proteins (7350, 8446, 10850, and 14693) appeared to be early malignant changes in histologically benign BE. Mass spectrometry performed upon fresh-frozen Barrett's epithelium, obtained by laser-capture microdissection, displays reproducible, tissue-specific, protein profiles. Distinct differences are demonstrated between benign and malignant epithelium, some of which appear to be candidate biomarkers of early malignant change. This technique reliably displays cellular protein expression in esophageal epithelium and deserves further study as a tool to identify early malignant degeneration in BE.