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Noriyoshi Fukushima

Publications and source records attributed to Noriyoshi Fukushima.

At least 19 recordsLinked to original sources

Differentiating pancreatic lesions by microarray and QPCR analysis of pancreatic juice RNAs.

BACKGROUND: The gene expression profile of pancreatic cancer is significantly different from that of normal pancreas. Differences in gene expression are detectable using microarrays, but microarrays have traditionally been applied to pancreatic cancer tissue obtained from surgical resection. We hypothesized that gene expression alterations indicative of pancreatic cancer can be detected by profiling the RNA of pancreatic juice. METHODS: We performed oligonucleotide microarray analysis on RNA isolated from pancreatic juice obtained endoscopically after secretin stimulation from six patients with pancreatic cancer and ten patients with nonneoplastic diseases of the pancreas or upper gastrointestinal tract. Extracted RNA was subjected to two rounds of linear RNA amplification, and then hybridized with U133A or X3P gene chips (Affymetrix). RESULTS: Using the U133A or X3P chips, 37 and 133 gene fragments respectively, were identified as being at least 3-fold more abundant in the pancreatic juice of patients with pancreatic cancer compared to the noncancer controls (p<0.05, Mann-Whitney test). For example, pancreatic juice from patients with pancreatic cancer contained increased levels of IL8, IFITM1, fibrinogen, osteopontin, CXCR4, DAF and NNMT RNA, genes that have been previously reported as overexpressed in primary pancreatic cancers or pancreatic cancer cell lines relative to control tissues. CONCLUSIONS: These results demonstrate that RNA analysis of pancreatic juice can reveal some of the same RNA alterations found in invasive pancreatic cancers. RNA analysis of pancreatic juice deserves further investigation to determine its utility as a tool for the evaluation of pancreatic lesions.

Chronic Disease↗

Aberrant methylation of Reprimo correlates with genetic instability and predicts poor prognosis in pancreatic ductal adenocarcinoma.

BACKGROUND: The p53-dependent G2/M checkpoint plays a key role in the maintenance of genomic integrity, thereby protecting cells from neoplastic progression. Reprimo, a gene involved in the p53-induced G2 cell cycle arrest, has been recently identified as a novel target for aberrant methylation in pancreatic and other cancers. The biological and clinical relevance of Reprimo methylation in pancreatic cancer was investigated. METHODS: The methylation status of Reprimo CpG island was analyzed by methylation-specific polymerase chain reaction in a large series of pancreatic cancers and was correlated with p53 mutation status, genetic instability (as measured by the fractional allelic loss), and clinicopathologic features. RESULTS: Aberrant methylation of Reprimo was identified in 60% (75 of 125) of pancreatic cancer xenografts and primary pancreatic adenocarcinomas. Reprimo methylation was also detectable in 30% (19 of 63) of pancreatic intraepithelial neoplasias (PanIN), known precursors to infiltrating carcinoma. Reprimo methylation was unrelated to the p53 mutation status and associated with the increased degree of genetic instability (P = .04). Furthermore, we found that patients with Reprimo methylation in their primary pancreatic cancers have significantly worse prognosis than those without Reprimo methylation (P = .007). In contrast, other methylation targets in pancreatic cancers (SPARC and CXCR4) did not correlate with prognosis. CONCLUSIONS: These results suggest that aberrant methylation of Reprimo is a common event in pancreatic carcinogenesis and is associated with genetic instability and unfavorable outcome after surgical resection.

Carcinoma, Pancreatic Ductal↗

Differential and epigenetic gene expression profiling identifies frequent disruption of the RELN pathway in pancreatic cancers.

BACKGROUND & AIMS: Recently described genome-wide approaches robustly detect many candidate genes that are regulated by DNA methylation, but many of these genes do not represent important targets for functional inactivation. Here we used a microarray-based strategy to identify biologically relevant genes associated with epigenetic silencing in pancreatic cancer. METHODS: We compared information from differential gene expression analysis with the transcriptional responses to epigenetic modifiers. RESULTS: Using this approach, we identified 7 novel targets for aberrant methylation in pancreatic cancer. One of the genes identified, RELN (Reelin), a key regulator of neuronal migration, is frequently silenced in pancreatic cancers, as are several of its downstream mediators. Importantly, small interfering RNA-mediated knockdown of RELN in pancreatic cancer cells that retain RELN expression resulted in greatly enhanced cell motility, invasiveness, and colony-forming ability. Increased cell motility was also induced by knockdown of downstream components of the RELN pathway, including ApoER2, VLDLR, and DAB1. Treatment of pancreatic cancer cells with histone deacetylase inhibitors, valproic acid and suberoylanilide hydroxamic acid, restored the expression of RELN and DAB1 and markedly inhibited their migration. CONCLUSIONS: The high prevalence of the silencing of RELN pathway components and its reversal by histone deacetylase inhibitors suggest the importance of this pathway as a diagnostic and therapeutic target for pancreatic cancer.

Cell Adhesion Molecules, Neuronal↗

Classification of types of intraductal papillary-mucinous neoplasm of the pancreas: a consensus study.

Now that more than two decades have passed since the first reports of intraductal papillary-mucinous neoplasms (IPMNs), it has become clear that IPMN consists of a spectrum of neoplasms with both morphological and immunohistochemical variations. At a meeting of international experts on pancreatic precursor lesions held in 2003, it was agreed that a consensus classification of IPMN subtypes should be established to enable a more detailed analysis of the clinicopathological significance of the variations. Based on our experience and on information from the literature, we selected representative histological examples of IPMNs and defined a consensus nomenclature and criteria for classifying variants as distinctive IPMN subtypes including gastric type, intestinal type, pancreatobiliary type, and oncocytic type. These definitions can be used for further analyses of the clinicopathological significance of the variations of IPMN.

Biomarkers, Tumor↗

Epigenetic down-regulation of CDKN1C/p57KIP2 in pancreatic ductal neoplasms identified by gene expression profiling.

PURPOSE: Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is an increasingly identified precursor to infiltrating ductal adenocarcinoma. Although our knowledge of the clinical and pathologic features of IPMNs is increasing, the molecular mechanisms underlying these neoplasms remain poorly understood. EXPERIMENTAL DESIGNS: To provide further insight into the molecular pathobiology of IPMNs, global expression profiling was done to determine genes that are inactivated/down-regulated in IPMNs using oligonucleotide microarrays (Affymetrix). RESULTS: In total, 300 unique transcripts (217 known genes) were identified as highly underexpressed in 12 IPMNs (<10-fold lower and P < 0.05) compared with five normal pancreatic ductal epithelium samples obtained by laser capture microdissection. The differential expression of a selection of genes was confirmed using reverse-transcription PCR. One of the genes underexpressed at both the transcriptional and protein level in a significant proportion of IPMNs was the cyclin-dependent kinase inhibitor, CDKN1C/p57KIP2. CDKN1C expression was also decreased in many pancreatic cancer cell lines and was restored following treatment with a DNA methylation inhibitor (5-aza-2'-deoxycitidine) or, more potently, with a histone deacetylase inhibitor (trichostatin A). Partial methylation of the CDKN1C promoter CpG island was found in most, but not all, pancreatic cancer cell lines with reduced CDKN1C expression, and was also detectable in IPMNs. Furthermore, a subset of pancreatic cancers showed complete hypomethylation of LIT1, an imprinting control region important for the regulation of CDKN1C expression. Complete hypomethylation in these cancers was the result of deletion of the methylated LIT1 allele at 11p15.5 rather than loss of imprinting. CONCLUSIONS: These findings suggest that CDKN1C is commonly down-regulated in pancreatic ductal neoplasms through a combination of promoter hypermethylation, histone deacetylation, and loss of the maternal allele expressing CDKN1C.

Adenocarcinoma, Mucinous↗

Expression and prognostic significance of 14-3-3sigma and ERM family protein expression in periampullary neoplasms.

Aberrant gene expression in pancreatic ductal adenocarcinomas contributes to the dismal outcome of patients who develop this disease. The 5' region of 14-3-3sigma (stratifin) is hypomethylated in pancreatic adenocarcinomas and is associated with gene overexpression. In multiple experimental systems, ezrin (ERM, Radixin, Moesin) has been identified as being important in the metastatic behavior of pancreatic and other cancers. We investigated the prognostic significance of aberrant expression of 14-3-3sigma and the ERM proteins (Ezrin, radixin, Moesin) in a series of invasive periampullary adenocarcinomas including 300 infiltrating pancreatic adenocarcinomas, 54 ampullary adenocarcinomas, and 33 noninvasive intraductal papillary mucinous neoplasms from patients who underwent pancreaticoduodenal resection at The Johns Hopkins Hospital, Baltimore, MD, between 1991 and 2003. Two-hundred fourty-four (82%) primary infiltrating adenocarcinomas of the pancreas demonstrated positive expression of the 14-3-3sigma, 45 (15%) showed weak immunolabelling, and 9 (3%) were negative. 201 (68%) showed positive immunolabeling of the ERM proteins, 75 (25%) demonstrated weak expression and 20 (7%) no expression. A similar proportion of ampullary cancers showed 14-3-3sigma and ERM protein expression. Expression of 14-3-3sigma and ERM protein was more likely in poorly differentiated cancers (p = 0.00005), and their expression was associated with poor survival in univariate analysis (p = 0.09). By multivariate analysis, patients whose cancers expressed 14-3-3sigma, but not ERM tended to have a poorer prognosis (Hazard ratio, 1.4; 0.9-2.2, p = 0.14). Aberrant expression of 14-3-3sigma may contribute to the outcome of patients with pancreatic ductal adenocarcinoma.

14-3-3 Proteins↗

Gene expression profiles in pancreatic intraepithelial neoplasia reflect the effects of Hedgehog signaling on pancreatic ductal epithelial cells.

Invasive pancreatic cancer is thought to develop through a series of noninvasive duct lesions known as pancreatic intraepithelial neoplasia (PanIN). We used cDNA microarrays interrogating 15,000 transcripts to identify 49 genes that were differentially expressed in microdissected early PanIN lesions (PanIN-1B/2) compared with microdissected normal duct epithelium. In this analysis, a cluster of extrapancreatic foregut markers, including pepsinogen C, MUC6, KLF4, and TFF1, was found to be up-regulated in PanIN. Up-regulation of these genes was further validated using combinations of real-time reverse transcription-PCR, in situ hybridization, and immunohistochemistry in a total of 150 early PanIN lesions from 81 patients. Identification of these gastrointestinal transcripts in human PanIN prompted assessment of other foregut markers by both semiquantitative and real-time reverse transcription-PCR, revealing similar up-regulation of Sox-2, Gastrin, HoxA5, GATA4/5/6, Villin and Forkhead 6 (Foxl1). In contrast to frequent expression of multiple gastric epithelial markers, the intestinal markers intestinal fatty acid binding protein, CDX1 and CDX2 were rarely expressed either in PanIN lesions or in invasive pancreatic cancer. Hedgehog pathway activation induced by transfection of immortalized human pancreatic ductal epithelial cells with Gli1 resulted in up-regulation of the majority of foregut markers seen in early PanIN lesions. These data show frequent up-regulation of foregut markers in early PanIN lesions and suggest that PanIN development may involve Hedgehog-mediated conversion to a gastric epithelial differentiation program.

Biomarkers, Tumor↗

Epigenetic inactivation of TFPI-2 as a common mechanism associated with growth and invasion of pancreatic ductal adenocarcinoma.

Using microarrays, we have screened for genes reactivated by drugs that modify epigenetic mechanisms in pancreatic cancer cells. One of the genes identified was tissue factor pathway inhibitor 2 (TFPI-2), which encodes for a broad-spectrum serine proteinase inhibitor that negatively regulates the extracellular matrix degradation, an essential step in tumor invasion and metastasis. We therefore investigated the expression and methylation patterns of the TFPI-2 gene in pancreatic adenocarcinoma, and determined its role in tumor growth and invasion. In contrast to its abundant expression in normal pancreas, TFPI-2 mRNA was undetectable in a high fraction of pancreatic cancer cell lines and in primary pancreatic ductal neoplasms (IPMNs). Loss of TFPI-2 expression was associated with aberrant hypermethylation of its promoter CpG island. Treatment with the phorbol ester (PMA), known to stimulate the TFPI-2 promoter activity, augmented the TFPI-2 expression in cell lines with unmethylated or partially methylated TFPI-2, but failed to induce the expression in cell lines that harbored fully methylated TFPI-2. Aberrant methylation of TFPI-2 was also detected in 73% (102/140) of pancreatic cancer xenografts and primary pancreatic adenocarcinomas, was more likely in older patients with pancreatic cancer, and significantly correlated with progression of IPMNs (P=0.0002). Restored expression of the TFPI-2 gene in nonexpressing pancreatic cancer cells resulted in marked suppression in their proliferation, migration, and invasive potential in vitro. We thus conclude that epigenetic inactivation of TFPI-2 is a common mechanism that contributes to the aggressive phenotype of pancreatic ductal adenocarcinoma.

Adenocarcinoma↗

The chemokine receptor CXCR4 is regulated by DNA methylation in pancreatic cancer.

Despite the biological and clinical importance of the interaction between the chemokine receptor CXCR4 and its ligand CXCL12 (SDF-1alpha) in human cancers, little is known about transcriptional regulation of the CXCR4 gene. Although aberrant hypermethylation in cancer has been described typically in genes with tumor-suppressor properties, this epigenetic alteration has also been observed to affect potential cancer-promoting genes. We now demonstrate that DNA methylation influences CXCR4 expression in human pancreatic cancer. Gene expression profiling and reverse transcription-PCR identified a significant proportion of pancreatic cancer cell lines that displayed little or no CXCR4 mRNA expression. Using methylation-specific PCR, combined bisulfite restriction analysis, and bisulfite sequencing, we found the 5' CpG islands of the CXCR4 gene to be unmethylated in normal pancreas, whereas promoter hypermethylation was detected in 45% (9 of 20) of pancreatic cancer cell lines and in 46% (46 of 100) of primary pancreatic adenocarcinomas. There was a significant inverse correlation between methylation and mRNA expression level of CXCR4 (P=0.008) in a large panel of pancreatic cancer cell lines. Constitutive as well as inducible expression of CXCR4 could be restored in methylated cell lines pharmacologically using epigenetic modifying drugs. These findings demonstrate the first evidence for epigenetic regulation of CXCR4 in human cancers, providing new insights into the role of CXCR4/CXCL12 interactions in tumor progression.

Chemokine CXCL12↗

Homozygous deletion of the MTAP gene in invasive adenocarcinoma of the pancreas and in periampullary cancer: a potential new target for therapy.

Methylthioadenosine phosphorylase (MTAP) plays an important role in the salvage pathway for the synthesis of adenosine. Novel chemotherapeutic strategies exploiting the selective loss of MTAP function in cancers have been proposed. The MTAP gene, on chromosome 9p21, is frequently included within homozygous deletions of the p16INK4A/ CDKN2A gene. Biallelic deletions of the p16INK4A/CDKN2A gene are found in 40% of pancreatic cancers, suggesting that the MTAP gene may be frequently inactivated in pancreatic cancer and that selected patients with pancreatic cancer may benefit from therapies targeting this loss. We immunolabeled six xenografted pancreatic cancers with known MTAP and p16INK4A/CDKN2A gene status and found that immunolabeling mirrored gene status. Loss of expression of both MTAP and p16 was observed only in those pancreatic cancers with homozygous deletions that encompassed both the MTAP and p16INK4A/CDKN2A genes. We then immunolabeled a series of 320 microarrayed infiltrating pancreatic adenocarcinomas, 35 biliary adenocarcinomas, 54 ampullary cancers, and 35 noninvasive intraductal papillary mucinous neoplasms. Immunolabeling for MTAP was lost in 91 of the 300 (30%) evaluable pancreatic cancers, 9 of 54 (17%) ampullary cancers, 4 of 33 (12%) biliary cancers, and in 1 of 35 (3%) IPMNs. All neoplasms with loss of MTAP labeling also demonstrated loss of p16 labeling. These results suggest that MTAP expression is lost in approximately 30% of infiltrating pancreatic cancers and in a lower percentage of other periampullary neoplasms, that this loss is the result of homozygous deletions encompassing both the MTAP and p16INK4A/CDKN2A genes. Thus, pancreatic cancer is a promising cancer type in which to explore novel chemotherapeutic strategies to exploit the selective loss of MTAP function.

Adenocarcinoma↗

Gene expression alterations in the non-neoplastic parenchyma adjacent to infiltrating pancreatic ductal adenocarcinoma.

The non-neoplastic pancreatic parenchyma adjacent to infiltrating ductal adenocarcinoma demonstrates inflammation, fibrosis, acinar cell loss and small duct-like metaplasia of acinar cells. Similar morphologic changes are also observed in the setting of chronic pancreatitis. In addition, peritumoral acini have been shown to have alterations in gene expression even in the absence of morphological changes. To better understand the pancreatic acinar responses to infiltrating pancreatic ductal adenocarcinoma, we characterized gene expression patterns of pancreatic acinar tissue adjacent to infiltrating pancreatic ductal adenocarcinomas and compared them to gene expression patterns of acinar tissue affected by chronic pancreatitis as well as to those of normal pancreatic acini. Fresh-frozen pancreatic acinar tissue was microdissected from nine patients (three with pancreatic cancer, three with chronic pancreatitis, three with normal pancreata) using laser capture microdissection, and extracted RNA from each microdissection was subjected to two rounds of linear amplification and hybridized to oligonucleotide microarrays. Gene expression patterns were confirmed using quantitative RT-PCR and/or immunohistochemistry. A total of 20 genes was found to be overexpressed in peritumoral acinar tissue compared to normal acinar tissue and to acini affected by chronic pancreatitis. These 20 genes included pancreatitis-associated protein (HIP/PAP), a gene known to be overexpressed in acini adjacent to infiltrating pancreatic cancer, and the gene cartilage glycoprotein-39 (HC gp-39 or TKL-40). Serum HC gp-39 protein levels were significantly higher in patients with pancreatic cancer and in those with chronic pancreatitis than in controls without pancreatic disease. There was no significant difference in the levels of serum HC gp-39 in patients with pancreatic cancer and those with chronic pancreatitis. Our results demonstrate some of the molecular alterations in acinar cells that occur in response to adjacent infiltrating pancreatic ductal adenocarcinoma and reveal that such alterations can provide a rich source of markers of pancreatic cancer.

Adipokines↗

Precursors to invasive pancreatic cancer.

Pancreatic cancer, once invasive, is almost uniformly fatal. In order to alleviate the dismal prognosis associated with this disease, it is imperative that pancreatic cancer be recognized and treated prior to invasion. Understanding the morphology and biology of precursor lesions of invasive pancreatic cancer has therefore become an issue of paramount importance. In the last decade, significant progress has been in the recognition and appropriate classification of these precursor lesions, and the current review will focus on our state-of-the-art knowledge on this topic. Mucinous cystic neoplasms (MCNs), intraductal papillary mucinous neoplasms (IPMNs), and pancreatic intraepithelial neoplasia (PanIN) encompass the three known morphologically distinct precursors to invasive pancreatic cancer. In addition to discussion of the "classic" precursor entities, this review will also address some of the recent diagnostic controversies for these lesions, in particular features that distinguish IPMNs from PanIN lesions. Finally, the potential clinical impact of recognizing these precursor lesions in the context of early detection of pancreatic cancer will be discussed.

Adenocarcinoma, Mucinous↗

[Pathologic characteristics and evaluation of the pancreatic cancer].

Ductal adenocarcinoma is the most common tumor type of cancer of the pancreas. It is generally a poorly demarcated, white to grey-solid tumor located in the pancreatic head. Histologically, it is often well-to moderately-differentiated tubular adenocarcinoma along with marked desmoplastic change. There are three well-defined precursors to invasive cancer; mucinous cystic neoplasms (MCNs), intraductal papillary mucinous neoplasms (IPMNs), and pancreatic intraepithelial neoplasia PanINs. PanIN is now considered to be a precursor of pancreatic ductal adenocarcinoma based on molecular studies. However, it is difficult to distinguish between small IPMNs and PanINs pathologically because both of them often show similar epithelium with cytoplasmic mucin. IPMNs and MCNs can form similar invasive carcinomas such as tubular adenocarcinoma and/or mucinous carcinoma. Another focus of this review is the issue of pathologic evaluation of the surgically resected specimens. Histologic grading and pathologic staging of each case are important especially in terms of the clinical aspects. Careful attention should be paid to the processes and/or criteria of pathologic diagnosis.

Adenocarcinoma↗

Characterization of gene expression in mucinous cystic neoplasms of the pancreas using oligonucleotide microarrays.

Mucinous cystic neoplasms (MCNs) of the pancreas are uncommon neoplasms usually located in the body or tail of the pancreas and usually in females (>90% of cases). Clinically, they are often misdiagnosed as non-neoplastic pseudocysts leading to failed opportunities for curative resection. To better understand the biology of MCNs and to identify markers of the disease, we performed global gene expression profiling of MCNs using oligonucleotide microarrays. Using laser capture microdissection applied to frozen sections, RNA was extracted from the neoplastic epithelium of MCNs, from the adjacent 'ovarian-type' stroma of MCNs, from histologically normal pancreatic ductal epithelium, from pancreatic acinar tissue and from fibrous stroma in pancreata affected by chronic pancreatitis. Each RNA sample was subjected to two rounds of linear amplification followed by hybridization with U133A gene chips (Affymetrix). The expression patterns of selected genes were confirmed by quantitative RT-PCR and by immunohistochemistry using tissue microarrays containing 19 resected MCNs. A total of 114 known genes were overexpressed in the neoplastic epithelium compared to normal pancreatic ductal epithelium (>3-fold) including S100P, PSCA, c-myc, STK6/STK15, cathepsin E and pepsinogen C. Activation of the Notch pathway in the epithelial component of MCNs was evident by the demonstration of overexpression of Jagged1 and the downstream Notch pathway member Hes1. In the 'ovarian-type' stroma, several genes involved in estrogen metabolism were overexpressed including STAR and ESR1 genes. Some of the genes identified as overexpressed in these neoplasms may be useful as markers that can distinguish MCNs from non-neoplastic pancreatic cystic lesions.

Adult↗

LigAmp for sensitive detection of single-nucleotide differences.

We developed the LigAmp assay for sensitive detection and accurate quantification of viruses and cells with single-base mutations. In LigAmp, two oligonucleotides are hybridized adjacently to a DNA template. One oligonucleotide matches the target sequence and contains a probe sequence. If the target sequence is present, the oligonucleotides are ligated together and detected using real-time PCR. LigAmp detected KRAS2 mutant DNA at 0.01% in mixtures of different cell lines. KRAS2 mutations were also detected in pancreatic duct juice from patients with pancreatic cancer. LigAmp detected the K103N HIV-1 drug resistance mutation at 0.01% in plasmid mixtures and at approximately 0.1% in DNA amplified from plasma HIV-1. Detection in both systems is linear over a broad dynamic range. Preliminary evidence indicates that reactions can be multiplexed. This assay may find applications in the diagnosis of genetic disorders and the management of patients with cancer and infectious diseases.

Biomarkers, Tumor↗

Serum macrophage inhibitory cytokine 1 as a marker of pancreatic and other periampullary cancers.

PURPOSE: Patients with pancreatic ductal adenocarcinoma usually present with advanced-stage disease and a dismal prognosis. One effective strategy likely to improve the morbidity and mortality from pancreatic cancer would be the identification of accurate, noninvasive diagnostic markers that would enable earlier diagnosis of symptomatic patients and earlier detection of cancer in asymptomatic individuals at high risk for developing pancreatic cancer. In this study, we evaluated serum macrophage inhibitory cytokine-1 (MIC-1) as a marker of pancreatic cancer. EXPERIMENTAL DESIGN: MIC-1 expression in primary pancreatic cancers, intraductal papillary mucinous neoplasms, and pancreatic cancer cell lines was determined using the National Center for Biotechnology Information serial analysis of gene expression database, oligonucleotide microarrays analysis, in situ hybridization, and immunohistochemistry. Serum MIC-1 levels were determined by ELISA in 80 patients with pancreatic adenocarcinomas, in 30 patients with ampullary and cholangiocellular carcinomas, in 42 patients with benign pancreatic tumors, in 76 patients with chronic pancreatitis, and in 97 healthy control subjects. The diagnostic performance of serum MIC-1 as a marker of pancreatic cancer was compared with that of serum CA19-9. RESULTS: Oligonucleotide microarray and serial analysis of gene expression data demonstrated that MIC-1 RNA levels were higher in primary pancreatic cancers, intraductal papillary mucinous neoplasms, and pancreatic cancer cell lines than in nonneoplastic pancreatic ductal epithelium. MIC-1 expression was localized to the malignant epithelium in pancreatic adenocarcinomas by in situ hybridization. MIC-1 protein was expressed in 14 of 16 primary pancreatic adenocarcinomas (88%) by immunohistochemistry and was also expressed in some pancreata affected by pancreatitis but not in normal pancreas. Serum MIC-1 levels were significantly higher in patients with pancreatic ductal adenocarcinoma (mean +/- SD, 2428 +/- 2324 pg/ml) and in patients with ampullary and cholangiocellular carcinomas (2123 +/- 2387 pg/ml) than in those with benign pancreatic neoplasms (940 +/- 469 pg/ml), chronic pancreatitis (1364 +/- 1236 pg/ml), or in healthy controls (546 +/- 262 pg/ml). An elevated serum MIC-1 (defined as 2 SD above the mean for healthy controls) performed as well as CA19-9 (area under the receiver operating characteristic curve, 0.81 and 0.77, respectively), and the combination of MIC-1 and CA19-9 significantly improved diagnostic accuracy (P < 0.05; area under the receiver operating characteristic curve, 0.87; sensitivity, 70%; specificity, 85%). CONCLUSION: Serum MIC-1 measurement can aid in the diagnosis of pancreatic adenocarcinoma.

Adenocarcinoma↗

Identification of maspin and S100P as novel hypomethylation targets in pancreatic cancer using global gene expression profiling.

DNA hypomethylation is one of the major epigenetic alterations in human cancers. We have previously shown that genes identified as hypomethylated in pancreatic cancer are expressed in pancreatic cancer cell lines, but not in normal pancreatic ductal epithelium and can be reexpressed in nonexpressing cells using 'epigenetic modifying agents' such as DNA methyltransferase inhibitors. To identify additional targets for aberrant hypomethylation in pancreatic cancer, we used oligonucleotide microarrays to screen for genes that displayed expression patterns associated with hypomethylation. This analysis identified a substantial number of candidates including previously reported hypomethylated genes. A subset of eight genes were selected for further methylation analysis, and two cancer-related genes, maspin and S100P, were found to be aberrantly hypomethylated in a large fraction of pancreatic cancer cell lines and primary pancreatic carcinomas. Combined treatment with 5-aza-2'-deoxycytidie and trichostatin A resulted in synergistic induction of maspin and S100P mRNA in MiaPaCa2 cells where both genes were methylated. Furthermore, there was an inverse correlation between methylation and mRNA expression level for maspin and S100P in a large panel of pancreatic cancer cell lines. We also found a significant difference in the methylation patterns of maspin and two previously identified hypomethylated genes (trefoil factor 2 and lipocalin 2) between pancreatic and breast cancer cell lines, suggesting cancer-type specificity for some hypomethylation patterns. Thus, our present results confirm that DNA hypomethylation is a frequent epigenetic event in pancreatic cancer, and suggest that gene expression profiling may help to identify potential targets affected by this epigenetic alteration.

Calcium-Binding Proteins↗

Gene expression profiling identifies genes associated with invasive intraductal papillary mucinous neoplasms of the pancreas.

The molecular pathology of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas has not been well characterized, and there are no reliable markers to predict the presence of an associated invasive carcinoma in IPMNs. Using oligonucleotide microarrays, we performed a large-scale gene expression profiling of 12 IPMNs with or without an associated invasive carcinoma. A subset of genes identified was validated for the gene expression patterns in a large panel of IPMNs by reverse-transcription polymerase chain reaction and/or immunohistochemistry. A total of 673 transcripts were identified as expressed at significantly higher levels (P < 0.05 and at fivefold or greater) in IPMNs relative to normal pancreatic ductal epithelial samples. Of interest, many of the genes identified as overexpressed in IPMNs have also been previously reported to be highly expressed in infiltrating ductal adenocarcinoma of the pancreas. By analyzing genes overexpressed selectively in IPMNs with an associated invasive carcinoma (n = 7), we also identified a panel of genes potentially associated with the invasive phenotype of the neoplasms. Immunohistochemical validation revealed that claudin 4, CXCR4, S100A4, and mesothelin were expressed at significantly high frequency in invasive IPMNs than in noninvasive IPMNs. Notably, the expression of at least two of the four proteins was observed in 73% of 22 invasive IPMNs but in none of 16 noninvasive IPMNs (P < 0.0001). Our findings suggest that preoperative assessment of gene expression profiles may be able to differentiate invasive from noninvasive IPMNs.

Adenocarcinoma, Mucinous↗