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Michael Goggins

Publications and source records attributed to Michael Goggins.

At least 37 records · Page 2Linked to original sources

Expression of the caudal-type homeodomain transcription factors CDX 1/2 and outcome in carcinomas of the ampulla of Vater.

PURPOSE: Adenocarcinomas of the ampulla of Vater demonstrate a characteristic histology but vary significantly in outcome. As a consequence, prognostic factors for these cancers are poorly defined. The caudal-type homeodomain transcription factors 1 (CDX1) and 2 (CDX2) regulate axial development and intestinal differentiation. We assessed the expression of these putative intestinal epithelial-specific transcription factors and their influence on patient outcome. PATIENTS AND METHODS: Fifty-three resected carcinomas of the ampulla of Vater, 31 pancreatic ductal adenocarcinomas, and 15 extrahepatic biliary carcinomas were analyzed for CDX1 and CDX2 expression using immunohistochemistry. RESULTS: Forty percent of carcinomas of the ampulla of Vater but less than 5% of pancreatic and biliary adenocarcinomas expressed CDX. Expression of CDX was associated with a better prognosis (P = .0009). Individually, both CDX1 (P = .02) and CDX2 (P = .02) expression were associated with a survival advantage on univariate analysis. Advanced T stage (P = .02), lymph node metastases (P = .004), and vascular space invasion (P = .0009) were associated with a poor prognosis. Multivariate analysis revealed vascular space invasion (P = .01) and CDX expression (P = .01) to be independent prognostic factors. CONCLUSION: Expression of CDX was an independent marker of outcome in patients with resected adenocarcinoma of the ampulla of Vater. Expression of CDX may distinguish good prognosis intestinal-like tumors, which potentially arise within intestinal epithelium, from poorer prognosis pancreatobiliary tumors, which arise in adjacent pancreatic and/or biliary ductal epithelium.

Adenocarcinoma↗

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↗

Age- and disease-related methylation of multiple genes in nonneoplastic duodenum and in duodenal juice.

PURPOSE: Methylation of CpG islands contributes to gene silencing during cancer development, and although some methylation alterations are promising diagnostic markers of cancer, some CpG islands are also methylated in normal tissues. We have previously observed that some normally unmethylated CpG islands that undergo methylation in pancreatic cancers are normally methylated in the adjacent duodenum. Because duodenal methylation patterns are an important consideration when sampling pancreatic tissues for pancreatic cancer methylation alterations, we determined the DNA methylation patterns of 24 genes in the normal duodenum of patients with pancreatic disease and related these patterns to demographic factors. EXPERIMENTAL DESIGN: The nonneoplastic duodenal mucosa of 158 patients with pancreatic carcinoma and 41 patients with chronic pancreatitis was analyzed using methylation-specific PCR and combined bisulfite restriction analysis. Secretin-stimulated pancreatic/duodenal juice from 15 individuals undergoing endoscopic investigation for upper gastrointestinal disease was also analyzed. RESULTS: Low-level methylation was detectable by methylation-specific PCR in the nonneoplastic duodenum of many patients with pancreatic cancer and chronic pancreatitis as well as in the pancreaticoduodenal secretions of patients without pancreaticobiliary disease. For many genes, the prevalence of methylation increased with age and was more prevalent in patients with pancreatic cancer than in age-matched patients with chronic pancreatitis. Our results indicate that strategies to detect pancreatic cancer using aberrantly methylated genes should rely on analysis of pure pancreatic juice rather than on pancreatic juice collected within the duodenal lumen. Patients who develop pancreatic cancer may have a greater propensity to methylate CpG islands than age-matched controls.

Adult↗

Pancreaticobiliary cancers with deficient methylenetetrahydrofolate reductase genotypes.

BACKGROUND & AIMS: Methyl group deficiency might promote carcinogenesis by inducing DNA breaks and DNA hypomethylation. We hypothesized that deficient methylenetetrahydrofolate reductase (MTHFR) genotypes could promote pancreatic cancer development. METHODS: First, we performed a case-control study of germline MTHFR polymorphisms (C677T, A1298C) in 303 patients with pancreatic cancer and 305 matched control subjects. Pancreatic neoplasms frequently lose an MTHFR allele during tumorigenesis; we hypothesized that such loss could promote carcinogenesis. We therefore evaluated the cancer MTHFR genotypes of 82 patients with pancreaticobiliary cancers and correlated them to genome-wide measures of chromosomal deletion by using 386 microsatellite markers. Finally, MTHFR genotypes were correlated with global DNA methylation in 68 cancer cell lines. RESULTS: Germline MTHFR polymorphisms were not associated with an increased likelihood of having pancreatic cancer. Fractional allelic loss (a measure of chromosomal loss) trended higher in cancers with 677T genotypes than in cancers with other genotypes (P = .055). Among cancers with loss of an MTHFR allele, cancers with 677T MTHFR alleles had more deletions at folate-sensitive fragile sites (36.9%) and at tumor suppressor gene loci (68.5%) than 677C cancers (28.7% and 47.8%, P = .079 and .014, respectively). LINE1 methylation was lower in cancers with less functional 677T/TT genotypes (24.4%) than in those with 677CT (26.0%) and CC/C genotypes (32.5%) (P = .014). CONCLUSION: Cancers with defective MTHFR genotypes have more DNA hypomethylation and more chromosomal losses. Deficient MTHFR function due to loss of an MTHFR allele by an evolving neoplasm might, by promoting chromosomal losses, accelerate cancer development.

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↗

Concordant loss of MTAP and p16/CDKN2A expression in pancreatic intraepithelial neoplasia: evidence of homozygous deletion in a noninvasive precursor lesion.

The p16INK4A/CDKN2A (p16) gene on chromosome 9p21 is inactivated in >90% of invasive pancreatic cancers. In 40% of pancreatic cancers the p16 gene is inactivated by homozygous deletion, in 40% by an intragenic mutation coupled with loss of the second allele, and in 10-15% by hypermethylation of the p16 gene promoter. Immunohistochemical labeling for the p16 gene product parallels gene status, but does not provide information of the mechanism of p16 gene inactivation. The methylthioadenosine phosphorylase gene (MTAP) gene also resides on chromosome 9p21, approximately 100 kb telomeric to the p16 gene. The MTAP gene is frequently contained within p16 homozygous deletions, producing concordant loss of both p16 and MTAP gene expression. Concordant loss of both p16 and MTAP protein expression can therefore be used as a surrogate marker for p16 homozygous deletion. Here we immunolabeled a series of pancreatic intraepithelial neoplasia (PanIN) lesions of various histologic grades for the p16 and MTAP gene products using a high-throughput PanIN tissue microarray (TMA) format. We demonstrate concordant loss of p16 and MTAP protein expression in 6/73 (8%) PanINs, including five high-grade lesions and one low-grade lesion. Immunolabeling for both p16 and MTAP protein expression provides a tool to evaluate tissues with intact morphology for p16 gene homozygous deletions. The concordant loss of expression of both genes in PanIN lesions demonstrates that homozygous deletions of the p16 tumor suppressor gene can occur in noninvasive precursor lesions.

Cyclin-Dependent Kinase Inhibitor p16↗

Xenografting and harvesting human ductal pancreatic adenocarcinomas for DNA analysis.

Xenotransplantation (xenografting) of primary cancers or cancer cell lines into immunodeficient mice is a commonly used technique to assess tumor growth in response to a variety of experimental agents. When primary pancreatic cancers are xenografted, cancer cells proliferate in the mouse, but the human stroma does not. This growth pattern enables facile genetic analysis of cancer genetics profiles without the contamination of admixed stromal cells typical of primary cancers.

Adenocarcinoma↗

DNA methylation analysis in human cancer.

Many tumor suppressor genes (such as p16, Rb, VHL, E-cadherin, and hMLH1) that are silenced by mutation are also inactivated by gene silencing through DNA methylation. Characterization of genes hypermethylated in human cancers but not in normal tissues not only provides insights into cancer biology but also permits the use of methylation-specific polymerase chain reaction-based assays that could serve as diagnostic tests for the early detection and early diagnosis of this disease. To this end, research aimed at the identification and characterization of the methylation status of known and candidate tumor suppressor genes is one strategy for finding putative diagnostic markers. This chapter describes several methods of methylation analysis.

DNA Methylation↗

Identification of differentially expressed proteins in pancreatic cancer using a global proteomic approach.

Proteomics is the term used for the large-scale analysis of proteins in biological fluids or cells by biochemical methods. Two approaches are used for proteomics analysis: two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and a mass-spectrometry-based approach, such as surface-enhanced laser desorption ionization (SELDI). SELDI can be used for large protein profiling or peptide identification after enzymatic digestion. In pancreatic cancer, proteomics analysis can be performed with the aim to identify all differentially expressed proteins in cancer cells vs normal pancreatic cells. Protein profiling of pancreatic juice or serum may also identify biomarkers for pancreatic cancer that could be used as diagnostic markers or therapeutic targets. This chapter outlines the use of 2D-PAGE and SELDI for profiling the protein content of pancreatic juice samples and for identifying proteins differentially expressed in pancreatic cancer patient samples compared to control patient samples.

Electrophoresis, Gel, Two-Dimensional↗

Differentially expressed genes in pancreatic ductal adenocarcinomas identified through serial analysis of gene expression.

Serial analysis of gene expression (SAGE) is a powerful tool for the discovery of novel tumor markers. The publicly available online SAGE libraries of normal and neoplastic tissues (http://www.ncbi.nlm.nih.gov/SAGE/) have recently been expanded; in addition, a more complete annotation of the human genome and better biocomputational techniques have substantially improved the assignment of differentially expressed SAGE "tags" to human genes. These improvements have provided us with an opportunity to re-evaluate global gene expression in pancreatic cancer using existing SAGE libraries. SAGE libraries generated from six pancreatic cancers were compared to SAGE libraries generated from 11 non-neoplastic tissues. Compared to normal tissue libraries, we identified 453 SAGE tags as differentially expressed in pancreatic cancer, including 395 that mapped to known genes and 58 "uncharacterized" tags. Of the 395 SAGE tags assigned to known genes, 223 were overexpressed in pancreatic cancer, and 172 were underexpressed. In order to map the 58 uncharacterized differentially expressed SAGE tags to genes, we used a newly developed resource called TAGmapper (http://tagmapper.ibioinformatics.org), to identify 16 additional differentially expressed genes. The differential expression of seven genes, involved in multiple cellular processes such as signal transduction (MIC-1), differentiation (DMBT1 and Neugrin), immune response (CD74), inflammation (CXCL2), cell cycle (CEB1) and enzymatic activity (Kallikrein 6), was confirmed by either immunohistochemical labeling of tissue microarrays (Kallikrein 6, CD74 and DMBT1) or by RT-PCR (CEB1, Neugrin, MIC1 and CXCL2). Of note, Neugrin was one of the genes whose previously uncharacterized SAGE tag was correctly assigned using TAGmapper, validating the utility of this program. Novel differentially expressed genes in a cancer type can be identified by revisiting updated and expanded SAGE databases. TAGmapper should prove to be a powerful tool for the discovery of novel tumor markers through assignment of uncharacterized SAGE tags.

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↗

Identification of novel highly expressed genes in pancreatic ductal adenocarcinomas through a bioinformatics analysis of expressed sequence tags.

In most microarray experiments, a significant fraction of the differentially expressed mRNAs identified correspond to expressed sequence tags (ESTs) and are generally discarded from further analyses. We used careful bioinformatics analyses to characterize those ESTs that were found to be highly overexpressed in a series of pancreatic adenocarcinomas. cDNA was prepared from 60 non-neoplastic samples (normal pancreas [n = 20], normal colon [n = 10], or normal duodenal mucosal [n = 30]) and from 64 pancreatic cancers (resected cancers [n = 50] or cancer cell lines [n = 14]) and hybridized to the complete Affymetrix Human Genome U133 GeneChip(R) set (arrays U133A and B) for simultaneous analysis of 45,000 fragments corresponding to 33,000 known genes and 6,000 ESTs. The GeneExpress(R) software system Fold Change Analysis Tool was used and 60 ESTs were identified that were expressed at levels at least 3-fold greater in the pancreatic cancers as compared to normal tissues. Searches against the human genomic sequence and comparative genomic analysis of human and mouse genomes was carried out using basic local alignment search tools (BLAST), BLASTN, and BLASTX, for identifying protein coding genes corresponding to the ESTs. Subsequently, in order to pick the most relevant candidate genes for a more detailed analysis, we looked for domains/motifs in the open reading frames using SMART and Pfam programs. We were able to definitively map 43 of the 60 ESTs to known or novel genes, and 15 of the ESTs could be localized in close proximity to a gene in the human genome although we were unable to establish that the EST was indeed derived from those genes. The differential expression of a subset of genes was confirmed at the protein level by immunohistochemical labeling of tissue microarrays (inhibin beta A [INHBA] and CD29) and/or at the transcript level by RT-PCR (INHBA, AKAP12, ELK3, FOXQ1, EIF5A2, and EFNA5). We conclude that bioinformatics tools can be used to characterize differentially overexpressed ESTs, and that some of these ESTs may represent diagnostically and therapeutically useful targets that might be missed using data solely from currently annotated databases.

Adenocarcinoma↗

Mac-2-binding protein is a diagnostic marker for biliary tract carcinoma.

BACKGROUND: Biliary tract carcinoma is a deadly disease, accounting for nearly 4500 malignancy-related deaths each year in the United States. Early detection has the potential to improve survival for patients with biliary tract malignancies, enabling curative surgical resection. Early detection approaches would benefit from an accurate, minimally invasive diagnostic test. To identify novel diagnostic markers, the authors recently completed a comprehensive proteomic study of bile samples from patients with biliary carcinoma. One of the proteins identified by tandem mass spectrometry was Mac-2-binding protein (Mac-2BP). The authors evaluated the performance of Mac-2BP and its ligand, galectin-3, as diagnostic markers for patients with biliary carcinoma. METHODS: Levels of Mac-2BP, galectin-3, and CA19-9 were measured using an enzyme-linked immunosorbent assay (ELISA) in bile samples from patients with biliary tract carcinoma (n = 26), benign biliary conditions (n = 32), and primary sclerosing cholangitis (n = 20). Serum levels of Mac-2BP and galectin-3 also were determined using ELISA. Mac-2BP tissue expression was investigated by immunohistochemical methods using a biliary carcinoma tissue microarray. RESULTS: Biliary Mac-2BP levels were elevated by a factor of approximately 3 in the biliary carcinoma group compared with the group of patients who had PSC or another type of nonneoplastic biliary disease. In contrast, Mac-2BP levels were not elevated in serum samples from patients with biliary carcinoma. According to the immunohistochemical analysis, Mac-2BP was expressed in 34 of 36 patients (94.4%) with biliary tract carcinoma. As a diagnostic marker for biliary carcinoma, Mac-2BP levels were as accurate as biliary CA19-9 levels, with an area under the curve (AUC) of 0.70 on receiver operator characteristic analysis. The use of both of these bile markers in combination, however, led to significantly better diagnostic accuracy compared with the accuracy achieved using CA19-9 alone (AUC, 0.75; P < 0.001). Serum and biliary galectin-3 levels did not differ in the biliary carcinoma group relative to the control groups. CONCLUSIONS: Biliary Mac-2BP levels, especially when used in conjunction with biliary CA19-9 levels, showed promise as a novel diagnostic marker for biliary tract carcinoma.

Aged↗

Gene expression profiling of tumor-stromal interactions between pancreatic cancer cells and stromal fibroblasts.

The interactions between cancer cells and surrounding stroma play a critical role in tumor progression, but their molecular basis is largely unknown. Global gene expression profiling was performed using oligonucleotide microarrays to determine changes in the gene expression of pancreatic cancer cells (CFPAC1) and stromal fibroblasts induced by coculture. This analysis identified multiple genes as differentially expressed in pancreatic cancer cells and in fibroblasts as a consequence of their mutual interactions, including those that encode for proteins associated with tumor invasion, metastasis, and angiogenesis. Among the genes identified, the cyclooxygenase-2 (COX-2)/PTGS2 gene was of particular interest because COX-2 expression was markedly augmented in both cell types (cancer cells and fibroblasts) in response to coculture. Coculture with fibroblasts also induced COX-2 expression in additional pancreatic cancer cells with an unmethylated COX-2 promoter, but not in those with a methylated COX-2 promoter. Using an in vitro invasion assay, we found an increase in the invasive potential of CFPAC1 cells when they were cocultured with fibroblasts, an effect blocked partially by the addition of a selective COX-2 inhibitor, NS-398, or by COX-2 knockdown with small interfering RNA. Thus, COX-2 inhibitors can decrease the invasive properties of pancreatic cancer cells acquired through tumor-stromal interactions.

Cell Communication↗

Mesothelin-specific CD8(+) T cell responses provide evidence of in vivo cross-priming by antigen-presenting cells in vaccinated pancreatic cancer patients.

Tumor-specific CD8(+) T cells can potentially be activated by two distinct mechanisms of major histocompatibility complex class I-restricted antigen presentation as follows: direct presentation by tumor cells themselves or indirect presentation by professional antigen-presenting cells (APCs). However, controversy still exists as to whether indirect presentation (the cross-priming mechanism) can contribute to effective in vivo priming of tumor-specific CD8(+) T cells that are capable of eradicating cancer in patients. A clinical trial of vaccination with granulocyte macrophage-colony stimulating factor-transduced pancreatic cancer lines was designed to test whether cross-presentation by locally recruited APCs can activate pancreatic tumor-specific CD8(+) T cells. Previously, we reported postvaccination delayed-type hypersensitivity (DTH) responses to autologous tumor in 3 out of 14 treated patients. Mesothelin is an antigen demonstrated previously by gene expression profiling to be up-regulated in most pancreatic cancers. We report here the consistent induction of CD8(+) T cell responses to multiple HLA-A2, A3, and A24-restricted mesothelin epitopes exclusively in the three patients with vaccine-induced DTH responses. Importantly, neither of the vaccinating pancreatic cancer cell lines expressed HLA-A2, A3, or A24. These results provide the first direct evidence that CD8 T cell responses can be generated via cross-presentation by an immunotherapy approach designed to recruit APCs to the vaccination site.

Antigen-Presenting Cells↗