Non-neoplastic Mucosa Research Articles

CONCURRENT ENTEROPATHY-ASSOCIATED T-CELL LYMPHOMA AND JEJUNAL ADENOCARCINOMA IN PATIENT WITH COELIAC DISEASE: A CASE REPORT

IntroductionAlthough coeliac disease (CD) is classically associated with malabsorption and the attendant complications arising from it, population studies have shown that patients with celiac disease (CD) are at increased risk...

Identification of stromal differentially expressed proteins in the colon carcinoma by quantitative proteomics

Tumor microenvironment plays very important roles in the carcinogenesis. A variety of stromal cells in the microenvironment have been modified to support the unique needs of the malignant state. This study was to discover stromal differentially expressed proteins (DEPs) that were involved in colon carcinoma carcinogenesis. Laser capture microdissection (LCM) was captured and isolated the stromal cells from colon adenocarcinoma (CAC) and non-neoplastic colon mucosa (NNCM) tissues, respectively. Seventy DEPs were identified between the pooled LCM-enriched CAC and NNCM stroma samples by iTRAQ-based quantitative proteomics. Gene Ontology (GO) relationship analysis revealed that DEPs were hierarchically grouped into 10 clusters, and were involved in multiple biological functions that were altered during carcinogenesis, including extracellular matrix organization, cytoskeleton, transport, metabolism, inflammatory response, protein polymerization, and cell motility. Pathway network analysis revealed 6 networks and 56 network eligible proteins with Ingenuity pathway analysis. Four significant networks functioned in digestive system development and its function, inflammatory disease, and developmental disorder. Eight DEPs (DCN, FN1, PKM2, HSP90B1, S100A9, MYH9, TUBB, and YWHAZ) were validated by Western blotting, and four DEPs (DCN, FN1, PKM2, and HSP90B1) were validated by immunohistochemical analysis. It is the first report of stromal DEPs between CAC and NNCM tissues. It will be helpful to recognize the roles of stromas in the colon carcinoma microenvironment, and improve the understanding of carcinogenesis in colon carcinoma. The present data suggest that DCN, FN1, PKM2, HSP90B1, S100A9, MYH9, TUBB, and YWHAZ might be the potential targets for colon cancer prevention and therapy.

Confocal Laser Endomicroscopy for the Differentiation of Normal from Neoplastic Barrett's Mucosa

Confocal laser endomicroscopy allows for in vivo microscopic scanning of the Barrett's segment and might improve the detection of neoplastic lesions. Here the basic principles of this innovative technique are shown and how to differentiate between normal gastric mucosa, nonneoplastic Barrett's mucosa, and Barrett's neoplasia is demonstrated. This article is part of an expert video encyclopedia.

Immunohistochemical expression and significance of NM23 suppressor protein in primary gastric adenocarcinoma

NM 23 protein was originally identified as a metastasis suppressor protein. The expression of NM23 has been correlated with tumour metastatic potential in various human carcinoma, mostly in ductal breast and colorectal carcinomas. Evidence for their expression in gastric cancer is rather contradictory, both for protein expression status and prognostic value. This study was done to analyze the immunohistochemical expression of NM23 in gastric carcinoma, and correlation of the degree of staining with clinicopathological parameters was investigated. In a retrospective immunohistochemical study specimens obtained from 56 gastric cancer patients who had undergone gastrectomy with perigastric lymphadenectomy were analysed, in correlation with classical clinical-pathological parameters of tumours, WHO-, Lauren-, Goseki-, and Ming- classification. NM 23 gene expression was compared in gastric adenocarcinoma and tumour-adjacent non-neoplastic gastric mucosa. A semiquantitative immunostaining evaluation (score 0-3) was used, counting the percentage of stained cells. Statistical analysis was performed using Kolmogorov-Smirnov test, and Spearman rank correlation test. The investigated group consisted of 40 males and 16 females (2.5:1) with a mean age of 63 years (range: 48-81 years). The percentage of positive expression of NM23 (score 3) were in 30 (53.5%) specimens in non-neoplastic mucosa in adjacent gastric carcinoma, and negative (score 0-2) in all 56 (100%) specimens of gastric adenocarcinoma. NM23 expression was higher in non-neoplastic mucosa than in adjacent gastric adenocarcinoma tissue (p<0.0001). NM23 protein expression did not correlate with gender (p=0.115), tumour size (p=0.844), tumour grade (p=0.172), lymphovascular invasion (p=0.606), lymph node metastases (p=0.311), Lauren classification (p=0.426), Goseki classification (p=0.458) and Ming classification (p=0.212). Our series did not show a significant correlation between NM23 expression and analysed clinico-pathological variables, but these results suggest that protein NM23 may have a role in gastric carcinoma pathogenesis.

Methylated miR-124, -137, and -34b/c as predictive biomarkers for ulcerative colitis-associated colorectal neoplasia.

e14631 Background: Accumulating evidence suggests that microRNAs (miRNAs) can be targets of methylation-induced silencing in colorectal cancer, which can occur in an age-dependent manner, and constitutes an epigenetic “field defect”. We hypothesized whether methylation of miR-124, -137 and -34b/c can predict colorectal neoplasia in patients with ulcerative colitis (UC). Methods: We examined 185 samples from 70 UC patients (45 patients without neoplasia, 12 with dysplasia and 13 with cancers) for the methylation status of miR-124, -137 and -34b/c by quantitative bisulfite pyrosequencing analysis. In addition, expression levels of these 3 miRNAs in dysplastic (n=12), cancerous (n=13) and non-neoplastic UC mucosa (n=20) were quantified by TaqMan qRT-PCR. Results: MiR-124 and -137 methylation levels were significantly higher in rectal tissues than in proximal mucosa from non-neoplastic UC tissues, and were significantly associated with age and disease duration in rectal tissues. Methylation levels of all 3 miRNAs were significantly higher in dysplasia and cancer compared to mucosa without neoplasia, and showed a “field defect” in the non-neoplastic rectal tissues from patients with cancer . Receiver operating characteristic (ROC) analysis revealed that methylation levels of all 3 miRNAs in non-neoplastic rectal tissues could discriminate patients with cancer from those without (miR-124 AUC value = 0.74; miR-137 AUC = 0.79; miR-34b/c AUC=0.72). Furthermore, methylated miR-137 in non-neoplastic rectal tissues allowed discrimination of UC patients with neoplasia from those without (AUC = 0.76), and independently predicted neoplasia (OR= 5.55; 95% CI: 1.40–22.05; P = 0.0148). Expression levels of all 3 miRNAs were significantly downregulated in dysplasia or cancer compared to non-neoplastic UC mucosa, and the expression and methylation were negatively correlated. Conclusions: Methylation of miR-124, -137 and -34b/c in rectal biopsies, particularly miR-137, may serve as novel predictive biomarkers for neoplasia in UC patients. Restoration of expression by reversing their methylation status could be an attractive strategy to slow or reverse age-related UC-associated neoplasia.

Flotillin2 Expression Correlates with HER2 Levels and Poor Prognosis in Gastric Cancer

ObjectiveFlotillin gene is known as a tumor promoter or suppressor, depending on the tumor type or tumor stage. We aimed to investigate the clinical significance of flotillin2 protein expression in gastric cancer.MethodsWe examined flotillin2 and erbB2 levels in tissue microarray of 282 gastric cancer samples and analyzed the association between flotillin2 levels, clinicopathologic factors and prognosis. The regulation of erbB2 by flotillin2 was examined with flotillin2 siRNA–transfected gastric cancer cells.ResultsFlotillin2 partially co-localized with erbB2 at the plasma membrane as detected by confocal microscopy, levels of erbB2 were reduced after flotillin knockdown in SGC-7901 cancer cells, and the expression of flotillin2 was positively correlated with that of erbB2. In non-neoplastic gastric mucosa, flotillin2 was not expressed in the epithelial compartment. In gastric cancer, positive staining of flotillin2 was shown in 129 (45.7%) of 282 cases, also, it was significantly associated with a Lauren grade, histologic type, lymphovascular invasion and tumor location. Moreover, survival analysis showed that flotillin2 expression was an independent prognostic factor of poor survival (p<0.001).ConclusionsThese results indicate that a positive correlation exists between flotillin2 and erbB2 expression levels, flotillin2 maybe involved in the stabilization of erbB2 at the plasma membrane, flotillin2 is significantly correlated with cancer progression and poor prognosis in gastric cancer.

Dysregulation of CDX1, CDX2 and SOX2 in patients with gastric cancer also affects the non-malignant mucosa

The interplay between gastric and intestinal transcription factors has an important impact on gastric carcinogenesis. We compared the gene expression of CDX1, CDX2, SOX2 and related downstream genes in tumour...

S100 calcium-binding protein A4 is a novel independent prognostic factor for the poor prognosis of gastric carcinomas

Overexpression of the S100 calcium-binding protein A4 (S100A4) is involved in epithelial-to-mesenchymal transition, oncogenic transformation, angiogenesis, cytoskeletal integrity and cancer metastasis. Here, we elucidated the role of S100A4 in tumorigenesis and progression of gastric carcinomas. S100A4 expression in gastric carcinomas, adenomas and adjacent non-neoplastic mucosa was analyzed by immunohistochemical, real-time reverse transcriptase (RT)-polymerase chain reaction (PCR) and western blot analyses, and was correlated with various clinicopathological parameters. S100A4 protein expression was increased gradually in the following order: gastritis (19.2%), intestinal metaplasia (IM; 23.3%), dysplasia (34.9%) and carcinoma (55.2%; P<0.001). S100A4 was positively correlated with tumor size, depth of invasion, lymphatic invasion, lymph node metastasis and tumor-node-metastasis (TNM) staging (P<0.05), but not with the age and gender of the carcinoma patients (P>0.05). Intestinal-type (IT) carcinomas showed a higher S100A4 expression than diffuse-type (DT) carcinomas (P<0.001). S100A4 mRNA expression also increased in the following order: gastritis < IM < dysplasia < carcinoma (P<0.05). S100A4 overexpression was observed in gastric carcinomas with a larger diameter, deeper invasion, lymph node metastasis and in IT carcinoma (P<0.05). Univariate analysis using the Kaplan-Meier method indicated a lower cumulative survival rate for patients with weak or moderate S100A4 expression compared with patients not expressing S100A4 (P<0.001). Multivariate analysis using Cox's proportional hazard model demonstrated that depth of invasion, lymphatic or venous invasion, lymph node metastasis, TNM staging and S100A4 expression were independent factors for poor patient prognosis (P<0.05). In conclusion, S100A4 upregulation is positively associated with the pathogenesis, growth, invasion, metastasis and differentiation of gastric carcinomas. S100A4 may be a promising marker indicative of the aggressive behavior and prognosis of gastric carcinomas.

Abstract 182: Differential response of epithelial cells from colorectal adenomas and adjacent nonneoplastic colonic mucosa to aspirin and atorvastatin in Apc+/Min-FCCC mice.

Abstract Although various agents have been identified that are efficacious in inhibiting colorectal adenomas in humans, the precise mechanisms responsible for their antitumor activity remain ill-defined. Significant insight into the use of agents for the prevention and treatment of colorectal cancer can be gained by examining the biological response of nonneoplastic colonic mucosa and colorectal adenomas to drug exposure. The present study compared the gene expression profile of neoplastic and nonneoplastic colonic epithelial cells following short-term administration of aspirin and atorvastatin to a strain of mice that uniquely develop multiple colorectal adenomas (Apc+/Min-FCCC). Tumor-bearing male Apc+/Min-FCCC mice (70 days of age) received either control Teklad 2018SX diet or diet supplemented with aspirin (300 ppm) or atorvastatin (100 ppm) for 7 days. At euthanasia, the colon was examined for gross lesions and matched pairs of colorectal adenomas and adjacent normal mucosa were frozen in OCT for gene expression analyses. Colonic epithelial cells were laser microdissected from pairs of pathologically-confirmed colorectal adenomas and nonneoplastic mucosa (4/treatment group). Amplified RNA was subjected to gene expression profiling using Agilent Mouse Whole Genome 4 X 44K microarrays. Genes differentially expressed in colon tissue from untreated vs. drug-treated mice were identified using LIMMA methodology and filtered (p = 0.01). The number of unique genes differentially expressed in neoplastic epithelial cells exposed to aspirin was 1052, while a much smaller set of genes (N=74) was altered in the nonneoplastic epithelium. Functional enrichment analyses revealed that the pathways modulated in nonneoplastic cells (i.e. protein folding, posttranscriptional regulation, DNA damage response, vascular permeability) were distinct from those altered in adenomas (i.e. cell adhesion, DNA repair, TOR signaling, apoptosis, glucose transport). In contrast, fewer genes were differentially expressed in neoplastic cells (N = 286) than in the adjacent nonneoplastic colonic mucosa (N = 749) following exposure to atorvastatin. The majority of the cellular processes modified in nonneoplastic cells by atorvastatin (i.e. DNA damage, cell death, immune function, cilium assembly) differed from those affected in neoplastic cells (i.e. lipid metabolism, apoptosis, cell cycle control, DNA repair). These data suggest that the mechanisms responsible for the protection conferred to nonneoplastic cells by aspirin or atorvastatin vary from those that lead to inhibition of tumor growth. Further mining of these expression data when combined with endoscopic monitoring of individual lesions during drug exposure should significantly enhance our understanding of the cellular processes responsible for their activity. (Supported by NIH N01 CN43309) Citation Format: Lisa Vanderveer, Suresh Paramasivam, Kara Williams, Harry Cooper, Karthik Devarajan, Suraj Peri, Yan Zhou, Laura Henik, Wen-Chi Chang, Ronald Lubet, Margie Clapper. Differential response of epithelial cells from colorectal adenomas and adjacent nonneoplastic colonic mucosa to aspirin and atorvastatin in Apc+/Min-FCCC mice. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 182. doi:10.1158/1538-7445.AM2013-182

Bag-3 expression is involved in pathogenesis and progression of colorectal carcinomas.

Bcl-2-associated athanogene 3 (Bag-3) belongs to a member of the Hsc70 binding co-chaperone Bag-family proteins and has critical roles in protein homeostasis, cell survival, actin organization, cell adhesion, cell motility and tumor metastasis. To clarify the role of Bag-3 in colorectal carcinogenesis and subsequent development, its expression was examined by immunohistochemistry (IHC) and in situ hybridization (ISH) on tissue microarrays containing colorectal carcinomas, adenomas, non-neoplastic mucosa (NNM) and metastatic carcinomas in lymph node and liver. Colorectal carcinoma tissue and cell lines were studied for Bag-3 expression by RT-PCR, Western blot and immunofluorescence. The results demonstrated that Bag3 was distinctly expressed in Colo201, Colo205, DLD-1, HCT-15, HCT-116, HT-29, KM-12, SW480, SW620, and WiDr at both mRNA and protein levels. Carcinoma showed stronger Bag-3 expression than adjacent NNM by IHC and Western blot (P<0.05), while its mRNA had the opposite by real-time PCR and ISH (P<0.05). Metastatic carcinoma more frequently expressed Bag-3 mRNA in lymph node and liver than in primary carcinoma (P<0.05). Immunohistochemically, Bag-3 expression was seen to gradually decrease from carcinoma, adenoma to NNM (P<0.05). There was a positive correlation between Bag-3 expression and TNM staging and GRP94 expression (P<0.05), but no relationship to patient age or sex, tumor size, depth of invasion, lymphatic or venous invasion, lymph node metastasis, differentiation or prognosis of colorectal carcinomas (P<0.05). Our study indicated that aberrant Bag-3 expression might be involved in colorectal adenoma-adenocarcinoma sequence and subsequent progression.

MicroRNA-25 functions as a potential tumor suppressor in colon cancer by targeting Smad7

Because it is a member of the miR-106b∼25 cluster, microRNA-25 (miR-25) is known to be dysregulated in human cancers. However, the expression and role of miR-25 in colon cancer remain unclear. In this study, miR-25 was found to be down-regulated in human colon cancer tissues when compared to those in matched, non-neoplastic mucosa tissues. Functional studies revealed that restoration of miR-25 expression inhibited cell proliferation and migration. In contrast, miR-25 inhibition could promote the proliferation and migratory ability of cells. Stable over-expression of miR-25 also suppressed the growth of colon cancer-cell xenografts in vivo. Furthermore, bioinformatic predictions and experimental validation were used to identify Smad7 as a direct target of miR-25. Functional reverse experiments indicated that the antitumor effects of miR-25 were probably mediated by its repression of Smad7. These results suggest that miR-25 may function as a tumor suppressor by targeting Smad7 in colon cancer. Thus, miR-25 may serve as a potential therapeutic agent or target for cancer therapy.

Altered Expression of Endogenous Soluble Vascular Endothelial Growth Factor Receptor-2 Is Involved in the Progression of Esophageal Squamous Cell Carcinoma

Endogenous soluble vascular endothelial growth factor receptor-2 (esVEGFR-2), a new splicing variant of VEGFR-2, was shown to be the first endogenous specific inhibitor of lymphatic vessel growth. The expression of esVEGFR-2 and its clinicopathological roles in esophageal squamous cell carcinoma (ESCC) are unclear. In this article, quantitative RT-PCR was employed to detect the mRNA levels of esVEGFR-2 and VEGF-C in 90 paired primary ESCC tissues, along with immunohistochemical staining to measure esVEGFR-2 protein in 182 ESCC primary tissues. Correlations between esVEGFR-2 expression and clinicopathological features were also analyzed. Compared with the corresponding non-neoplastic esophageal mucosa tissues, the mRNA level of esVEGFR-2 was decreased, whereas the mRNA level of VEGF-C was increased in ESCCs. Downregulation of esVEGFR-2 mRNA level was significantly correlated with pTNM stages (χ(2) = 7.790, p=0.02). Immunohistochemical staining of esVEGFR-2 was inclined to be reduced in ESCC tissues; lower esVEGFR-2 protein expression was related to better prognosis (χ(2) = 6.366, p=0.012), whereas higher esVEGFR-2 protein accumulation in ESCC tissues was an independent prognostic factor for poor survival of patients (hazard ratio, 1.606; 95% confidence interval, 1.042-2.476; p=0.032). Taken together, altered expression of esVEGFR-2 is correlated with progression of ESCC. esVEGFR-2 might serve as a new independent prognostic marker for ESCC patients.

Adiponectin receptor expression in gastric carcinoma: implications in tumor development and progression

Adiponectin, an adipocyte-secreted endogenous insulin sensitizer, appears to play an important role in progression of several malignancies. Expression of adiponectin receptors--AdipoR1 and AdipoR2--has been documented in gastric cancer (GC) cell lines, but its role in GCs is still controversial. We investigated expression level of 2 adiponectin receptors and correlated their expression with prognosis in GC patients. We immunohistochemically evaluated AdipoR1 and AdipoR2 expression in 59 non-neoplastic gastric mucosas, 48 gastric adenomas, 250 GCs, and 58 lymph nodes involved by metastatic GC and assessed its association with clinicopathologic characteristics. Expression rates of both receptors increased stepwise in non-neoplastic gastric mucosa, gastric adenoma, intestinal-type GC, and metastatic GC (p < 0.001). AdipoR1 and AdipoR2 expression was observed in 85 (34.0 %) and 118 (47.2 %) GC cases, respectively. Expression rates were higher in intestinal-type GC than in diffuse-type GC (p < 0.001 and 0.016, respectively). AdipoR1 and AdipoR2 expression was more frequent in advanced GC than in early GC (p < 0.001, each) and was associated with lymphatic invasion (p = 0.046 and 0.001, respectively). AdipoR2 expression was associated with poor overall and disease-free survival (p = 0.001 and 0.007, respectively). AdipoR1 expression was associated with poor disease-free survival for intestinal-type GC patients (p = 0.046). In multivariate analysis, AdipoR2 was an independent prognostic factor for intestinal-type GC (p = 0.017). Adiponectin receptor expression is related to GC development and progression, especially intestinal-type GC. Thus, adiponectin receptor expression can serve as a prognostic marker in GC patients.

Beclin 1 expression is an independent prognostic factor for gastric carcinomas

Beclin 1, an important autophagy-related protein in human cells, is involved in autophagy, differentiation, anti-apoptosis, and cancer progression, which is increased during periods of cell stress and extinguished during the cell cycle. In order to clarify the role of Beclin 1 in gastric carcinogenesis and subsequent progression, its expression was examined by immunohistochemistry and in situ hybridization (ISH) on tissue microarrays containing gastric carcinomas, adjacent non-neoplastic mucosa, and metastatic lymph node. Gastric carcinoma tissue and cell lines were studied for Beclin 1 expression by Western blot or RT-PCR, respectively. The results demonstrated that Beclin 1 was distinctively expressed in GES-1, AGS, BGC-823, GT-3 TKB, HGC-27, KATO-III, MGC-803, MKN28, MKN45, SCH, SGC-7901, or STKM-2 at both mRNA and protein levels. However, Beclin 1 mRNA was highly expressed in gastric carcinoma than matched mucosa by real-time PCR and ISH (P < 0.05). Beclin 1 expression was negatively related to distant metastasis and poor prognosis of gastric carcinoma (P < 0.05). Beclin 1 was highly expressed in male than female patients with gastric carcinoma (P < 0.05). The 65-year-elder patients with gastric carcinoma had higher Beclin 1 expression than the younger ones (P < 0.05). The diffuse-type carcinomas showed less Beclin 1 expression than intestinal- and mixed-type ones (P < 0.05). In intestinal-type gastric carcinoma, Beclin 1 expression was inversely associated with venous invasion, lymph node metastasis, and tumor-node-metastasis (TNM) staging (P < 0.05). Kaplan-Meier analysis indicated that Beclin 1 expression was positively linked to favorable prognosis of the patients with overall and intestinal-type carcinoma (P < 0.05). Cox's proportional hazard model indicated that venous invasion, lymph node metastasis, distant metastasis, TNM staging, and Beclin 1 expression were independent prognostic factors for gastric carcinomas (P < 0.05). It was suggested that aberrant Beclin 1 expression is closely linked to pathogenesis, metastasis, and differentiation of gastric carcinoma. Beclin 1 expression might be employed to indicate the favorable prognosis of gastric carcinomas as an independent factor.

Overexpression of microRNAs-155 and 21 targeting mismatch repair proteins in inflammatory bowel diseases

Microsatellite instability (MSI) due to mismatch repair (MMR) deficiency is reported in 5-10% of colorectal cancers (CRCs) complicating inflammatory bowel diseases (IBD). The molecular mechanisms underlying MMR deficiency may be different in IBD CRCs, and in sporadic and hereditary MSI tumors. Here, we hypothesize that overexpression of miR-155 and miR-21, two inflammation-related microRNAs that target core MMR proteins, may constitute a pre-neoplastic event for the development of MSI IBD CRCs. We studied miR-155 and miR-21 expression using real-time quantitative PCR in MSI (n = 10) and microsatellite stable (n = 10) IBD CRCs, and in MSI (n = 32) and microsatellite stable (n = 30) non-IBD CRCs. We also screened colonic samples from IBD patients without cancer (n = 18) and used healthy colonic mucosa as controls (n = 20). MiR-155 and miR-21 appeared significantly overexpressed not only in the colonic mucosa of IBD subjects without CRC but also in neoplastic tissues of IBD patients compared with non-IBD controls (P < 0.001). Importantly, in patients with IBD CRCs, miR-155 and miR-21 overexpression extended to the distant non-neoplastic mucosa (P < 0.001). Ratios of expressions in tumors versus matched distant mucosa revealed a nearly significant association between miR-155 overexpression and MSI in IBDs (P = 0.057). These results show a strong deregulation of both MMR-targeting microRNAs in IBD subjects with or without cancer. MiR-155 overexpression being particularly associated to MSI IBD CRCs and extending to distant non-neoplastic mucosa, strongly suggests that a pre-neoplastic miR-155 field defect may promote MSI-driven transformation of the colonic mucosa. The detection and monitoring of miR-155 field defect may, therefore, have implications for the prevention and treatment of MSI IBD CRCs.

Expression Profiling of Proliferation and Apoptotic Markers along the Adenoma-Carcinoma Sequence in Familial Adenomatous Polyposis Patients

Introduction. Familial adenomatous polyposis (FAP) patients have a germline mutation in the adenomatous polyposis coli (APC) gene. The APC protein interacts with beta-catenin, resulting in the activation of the Wnt signalling pathway. This results in alterations in cell proliferation and apoptosis. We investigated the expression of beta-catenin and related proliferation and apoptotic factors in FAP patients, exploring the expression along the adenoma-carcinoma sequence. Methods. The expression of beta-catenin, p53, bcl-2, cyclin-D1, caspase-3, CD10, and Ki-67 proteins was studied by immunohistochemistry in samples of colonic nonneoplastic mucosa (n = 71), adenomas (n = 152), and adenocarcinomas (n = 19) from each of the16 FAP patients. Results. The expression of beta-catenin, caspase-3, cyclin-D1, and Ki-67 was increased in both adenomas and carcinomas in FAP patients, compared with normal mucosa. p53 and CD10 expression was only slightly increased in adenomas, but more frequently expressed in carcinomas. Bcl-2 expression was increased in adenomas, but decreased in carcinomas. Conclusion. This is the first study investigating collectively the expression of these molecules together in nonneoplastic mucosa, adenomas, and carcinomas from FAP patients. We find that beta-catenin and related proliferative and apoptotic factors (cyclin-D1, bcl-2, caspase-3, and Ki-67) are expressed early in the sequence, in adenomas. However, p53 and CD10 are often expressed later in the sequence, in carcinomas.

Cdx2 expression and its promoter methylation during metaplasia-dysplasia-carcinoma sequence in Barrett's esophagus

To examine how the expression of caudal type homebox transcription factor 2 (Cdx2) is regulated in the development of malignancy in Barrett's esophagus. Cdx2, mucin (MUC) series (MUC2, MUC5AC and MUC6), p53 and E-cadherin expression in Barrett's esophagus and adenocarcinoma specimens were examined by immunostaining. Isolated clusters of cells from (1) MUC2 and Cdx2-positive intestinal metaplastic mucosa; (2) MUC5AC and MUC6-positive, and MUC2 and Cdx2-negative high-grade dysplasia (HD), or intramucosal adenocarcinoma (IMC); and (3) MUC5AC, MUC6 and Cdx2-positive poorly-differentiated invasive adenocarcinoma (PDA) were analyzed by methylation-specific polymerase chain reaction using sets of primers for detecting methylation status of the Cdx2 gene. Most of the non-neoplastic Barrett's esophageal mucosa showing intestinal-type metaplasia with or without low-grade dysplasia was positive for E-cadherin, MUC series and Cdx2, but negative for p53. A portion of the low-grade to HD was positive for E-cadherin, MUC5AC, MUC6 and p53, but negative for MUC2 and Cdx2. The definite IMC area was strongly positive for MUC5AC, MUC6 and p53, but negative for MUC2 and Cdx2. Methylation of the Cdx2 promoter was not observed in intestinal metaplasia, while hypermethylation of part of its promoter was observed in hot dipped and IMC. Hypermethylation of a large fraction of the Cdx2 promoter was observed in PDA. Cdx2 expression is restored irrespective of the methylation status of its promoter. Apparent positive immunohistochemical results can be a molecular mark for gene silencing memory.

Expression of CD133 in Neuroendocrine Neoplasms of the Digestive Tract: A Detailed Immunohistochemical Analysis

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are potentially malignant with variable biologic behavior that originates from neuroendocrine cells of digestive tract. Recently, the existence of cancer stem cells (CSC) was demonstrated in tumors of gastrointestinal tract. CD133 is a transmembrane glycoprotein that serves as a CSC marker in various malignancies. However, the expression of CD133 in neuroendocrine neoplasms (NEN) of digestive tract has not been studied. We evaluated tissue expression of CD133 by immunohistochemistry in 90 NENs of digestive tract with their matched non-neoplastic mucosa including stomach (n=15), small intestine (n=7), appendix (n=3), colon (n=8), rectum (n=41), pancreas (n=2), gallbladder (n=4) and liver (n=10). Tumors were divided according to 2010 WHO classification. CD133 was expressed in 30.3% (17/56) of well-differentiated neuroendocrine tumors (NET), 26.1% (6/23) of poorly-differentiated neuroendocrine carcinomas (NEC) and 63.6% (7/11) of mixed adenoneuroendocrine carcinoma (MANECs). MANEC refers to existence of both adenocarcinoma and NEC together, each one comprising at least 30% of the tumor. CD133 was expressed in cytoplasm, luminal-side of cell membrane, or both and the staining pattern correlated with tumor growth pattern. CD133 expression was not significantly correlated with tumor grade, site, expression of neuroendocrine markers (chromogranin-A and synaptophysin) and patients' survival. Thus, CD133 expression may lack prognostic significance in GEP-NETs. Importantly, CD133 was not detectable in non-neoplastic neuroendocrine cells of digestive system including pancreatic islets. In conclusion, CD133 is expressed in poorly-differentiated NECs and well-differentiated NETs of the digestive tract.

Dome-Type Carcinoma of the Colon Masquerading a Submucosal Tumor

A 76-year-old woman was referred for treatment of a rectal submucosal tumor (SMT). Endoscopy revealed a broad-based elevated lesion, 10 mm in diameter in the lower rectum (Figure A). This lesion appeared to be covered entirely with non-neoplastic mucosa showing mild discoloration (Figure B). A tiny whitish exudate was observed on the top of the lesion. Based on these endoscopic findings, we diagnosed an SMT and completely removed the lesion by endoscopic submucosal resection with a ligation device.

Expression of C-X-C chemokine receptor types 1/2 in patients with gastric carcinoma: Clinicopathological correlations and significance.

C-X-C chemokine receptor types 1/2 (CXCR1/2) may play multiple roles in the development and progression of a number of types of tumor. The abnormal expression of CXCR1/2 in various types of malignant tumors has been reported, but less is known with regard to gastric carcinoma. The present study was preliminarily conducted to elucidate the correlation between clinicopathological factors and the immunohistochemical expression of CXCR1/2 in patients with gastric carcinoma. The expression of CXCR1/2 in 69 specimens of sporadic gastric carcinoma and their corresponding non-neoplastic mucosa obtained by gastrectomy was assayed by immunohistochemistry (IHC) using a polyclonal anti-CXCR1/2 antibody. ERK1/2 and AKT phosphorylation and the expression of indicators of proliferation, growth and apoptosis (Bcl-2 and Bax, Cyclin D1, EGFR and Ki-67), angiogenesis (VEGF and CD34), invasion and metastasis (MMP-9, MMP-2, TIMP-2 and E-cadherin) were also detected by IHC. A total of 68 (98.6%) of the 69 patients with gastric carcinoma were found to have positive CXCR1/2 expression, which appeared to be significantly higher in gastric carcinoma compared with corresponding non-neoplastic mucosa tissues. The expression of CXCR1/2 in gastric carcinoma was significantly associated with invasion, metastasis and TNM staging (P<0.001). Correlation analysis between CXCR1/2 and pAKT (P=0.032), pERK (P<0.001), Cyclin D1 (P=0.049), EGFR (P=0.013), Bcl-2 (P=0.003), microvessel density (P=0.001), MMP-9 (P=0.013) and MMP-2 (P=0.027) expression using the Spearman test showed significant correlation in gastric carcinoma. Univariate and multivariate logistic regression analysis showed that, compared with negative or weak expression, overexpression of CXCR1/2 protein was a significant risk factor for TNM stage (P<0.001). These results preliminarily suggest that CXCR1/2 may be a useful maker for progression of the tumors and a promising target for gastric carcinoma therapy.