Biomedical subjects

Michael Goggins

Publications and source records attributed to Michael Goggins.

At least 19 recordsLinked to original sources

PubMed2006

Detecting low-abundance p16 and p53 mutations in pancreatic juice using a novel assay: heteroduplex analysis of limiting dilution PCRs.

We have developed a simple, robust, highly-sensitive assay for identifying gene mutations in clinical samples. We applied this assay to detect p53 and p16 mutations in pancreatic juice obtained from patients undergoing evaluation and treatment of pancreatic disease. The assay strategy involves PCR amplifying DNA at limiting dilution (LD-PCR) followed by screening PCR products for mutations using temperature gradient capillary electrophoresis (TGCE). Compared to conventional TGCE, TGCE after LD-PCR significantly increased the number of detectable mutations in pancreatic duct juice. Using LD-PCR, mutations in p53 and/or p16 were found in the pancreatic juice of 12 of 20 individuals with pancreatic cancer compared to only 1 of 8 patients with chronic pancreatitis, 0 of 8 individuals without evidence of pancreatic disease (p<0.02). We conclude that limiting dilution PCR is an effective strategy for improving the detection of mutations in clinical samples and when applied to pancreatic juice to detect mutations of p53 and/or p16, it can help distinguish patients with pancreatic cancer from those without evidence of pancreatic neoplasia.

Diagnosis, Differential↗

PubMed2006

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↗

PubMed2006

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↗

PubMed2006

Screening for early pancreatic neoplasia in high-risk individuals: a prospective controlled study.

BACKGROUND & AIMS: Individuals with a strong family history of pancreatic cancer and persons with Peutz-Jeghers syndrome (PJS) have an increased risk for pancreatic cancer. This study screened for early pancreatic neoplasia and compared the pancreatic abnormalities in high-risk individuals and control subjects. METHODS: High-risk individuals with PJS or a strong family history of pancreatic cancer were prospectively evaluated with baseline and 12-month computed tomography (CT) scan and endoscopic ultrasonography (EUS). If EUS was abnormal, EUS-fine-needle aspiration and endoscopic retrograde cholangiopancreatography (ERCP) were performed. Surgery was offered to patients with potentially neoplastic lesions. Radiologic findings and pathologic diagnoses were compared. Patients undergoing EUS and/or ERCP for benign non-pancreatic indications were concurrently enrolled as control subjects. RESULTS: Seventy-eight high-risk patients (72 from familial pancreatic cancer kindreds, 6 PJS) and 149 control patients were studied. To date, 8 patients with pancreatic neoplasia have been confirmed by surgery or fine-needle aspiration (10% yield of screening); 6 patients had 8 benign intraductal papillary mucinous neoplasms (IPMNs), 1 had an IPMN that progressed to invasive ductal adenocarcinoma, and 1 had pancreatic intraepithelial neoplasia. EUS and CT also diagnosed 3 patients with 5 extrapancreatic neoplasms. At EUS and ERCP abnormalities suggestive of chronic pancreatitis were more common in high-risk patients than in control subjects. CONCLUSIONS: Screening EUS and CT diagnosed significant asymptomatic pancreatic and extrapancreatic neoplasms in high-risk individuals. IPMN should be considered a part of the phenotype of familial pancreatic cancer. Abnormalities suggestive of chronic pancreatitis are identified more commonly at EUS and ERCP in high-risk individuals.

Adult↗

PubMed2006

Real-time detection of mesothelin in pancreatic cancer cell line supernatant using an acoustic wave immunosensor.

BACKGROUND: An acoustic wave immunosensor was developed to illustrate the viability of such devices in early detection of molecular cancer biomarkers. The methods described here involve a real-time, less invasive technique for detecting mesothelin, a protein that has been linked to pancreatic and ovarian cancer. METHODS: Antibodies were immobilized on the gold surface of the device via a self-assembled alkanethiol monolayer. Supernatant from two different pancreatic cancer cell-lines (PL1 and CAPAN2) containing an unknown concentration of mesothelin was tested for the protein by a flow-through analytical technique in three types of experiments. Binding of the mesothelin to the immobilized antibody layer caused a shift in the device's resonant frequency, which was correlated to the concentration of supernatant. A reference sensor was used to correct for frequency shifts caused by pressure or viscosity effects from the injection of the supernatant solution. RESULTS: Repeated experiments indicate that the sensors are capable of nanogram detection thresholds of mesothelin proteins at room temperature and in complex mixture. CONCLUSIONS: Acoustic wave device biosensors have the potential to become a valuable tool in screening for pancreatic as well as other types of cancers. The main features include real-time detection, high sensitivity, and ease of use.

Antibodies, Monoclonal↗

PubMed2006

Quantification of fragments of human serum inter-alpha-trypsin inhibitor heavy chain 4 by a surface-enhanced laser desorption/ionization-based immunoassay.

BACKGROUND: Several proteolytically derived fragments from the proline-rich region (PRR) of human inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) have been identified by surface-enhanced or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS or MALDI-TOF-MS) as potential disease markers. METHODS: Previously, we developed a SELDI-based immunoassay that can simultaneously distinguish and quantify multiple isoforms/variants of a protein/peptide of interest. In this study, we used this high-throughput approach to quantify and characterize the extensive fragmentation within the PRR of human serum ITIH4 and determined its association with different disease conditions. The ITIH4-related fragments were first immunocaptured by use of beads coupled with peptide-specific antibodies. The eluates were then studied by SELDI-TOF-MS. In addition, freshly collected and immediately processed serum and plasma samples were used to analyze the ex vivo stability of these ITIH4 fragments. RESULTS: Human serum ITIH4 was shown to be extensively proteolytically processed within the PRR, and its fragmentation patterns were closely associated with different disease conditions. Fragmentation patterns were generally consistent with cleavages by endoprotease followed by exoprotease actions. Observed fragments changed little under different assay conditions or blood collection and processing procedures. CONCLUSIONS: The fragmentation patterns within the PRR of human serum ITIH4 are associated with different disease conditions and may hold important diagnostic information. These fragmentation patterns could be useful as potential biomarkers for detection and classification of cancer.

Adult↗

PubMed2006

DNA methylation alterations in the pancreatic juice of patients with suspected pancreatic disease.

Molecular markers of pancreatic neoplasia could aid in the evaluation of visible pancreatic lesions and indicate neoplasia invisible to imaging. We evaluated methylation-specific PCR (MSP) assays that detect aberrantly methylated DNA for their use as markers of pancreatic neoplasia. Methylation analysis was done on pancreatic juice collected endoscopically or surgically from 155 individuals with suspected pancreatic disease: 56 patients had pancreatic ductal adenocarcinoma, 17 had intraductal papillary mucinous neoplasms, 26 had symptomatic chronic pancreatitis, 12 controls lacked evidence of pancreatic disease, and 44 were asymptomatic individuals at increased risk of developing familial pancreatic cancer undergoing screening for pancreatic neoplasia. Pancreatic juice DNA was analyzed for promoter methylation using conventional MSP assays for 17 genes. For six genes, pancreatic juice methylation was quantified using real-time quantitative MSP (QMSP; Cyclin D2, FOXE1, NPTX2, ppENK, p16, and TFPI2). Quantifying pancreatic juice methylation using QMSP with a cutoff of >1% methylated DNA could better predict pancreatic cancer than detecting methylation using conventional MSP. In the endoscopic group, 9 of 11 patients with pancreatic cancer, but none of 64 individuals without neoplasia had > or =1% methylation for two or more of the best five QMSP assays (82% sensitivity and 100% specificity; P < 0.0001). The prevalence of pancreatic juice methylation in patients with chronic pancreatitis was less than in patients with pancreatic cancer but higher than in controls and similar to high-risk individuals. The detection and quantification of aberrantly methylated DNA in pancreatic juice is a promising approach to the diagnosis of pancreatic cancer.

Adenocarcinoma↗

PubMed2006

Serum markers in patients with resectable pancreatic adenocarcinoma: macrophage inhibitory cytokine 1 versus CA19-9.

PURPOSE: More accurate serum markers of pancreatic cancer could improve the early detection and prognosis of this deadly disease. We compared the diagnostic utility of a panel of candidate serum markers of pancreatic cancer. EXPERIMENTAL DESIGN: We collected preoperative serum from 50 patients with resectable pancreatic adenocarcinoma, as well as sera from 50 patients with chronic pancreatitis and 50 age/sex-matched healthy controls from our institution. Sera were analyzed for the following candidate markers of pancreatic cancer: CA19-9, macrophage inhibitory cytokine 1 (MIC-1), osteopontin, tissue inhibitor of metalloproteinase 1, and hepatocarcinoma-intestine-pancreas protein levels. RESULTS: By logistic regression analysis, MIC-1 and CA19-9 were significant independent predictors of diagnosis. Receiver operating characteristic curve analysis showed that MIC-1 was significantly better than CA19-9 in differentiating patients with pancreatic cancer from healthy controls (area under the curve is 0.99 and 0.78, respectively; P = 0.003), but not in distinguishing pancreatic cancer from chronic pancreatitis (area under the curve of 0.81 and 0.74, respectively; P = 0.63). Hepatocarcinoma-intestine-pancreas/pancreatitis-associated protein, osteopontin, and tissue inhibitor of metalloproteinase 1 serum levels did not provide additional diagnostic power. CONCLUSION: In the differentiation of patients with resectable pancreatic cancer from controls, serum MIC-1 outperforms other markers including CA19-9.

Adenocarcinoma↗

PubMed2006

Epigenetic alterations in intraductal papillary mucinous neoplasms of the pancreas.

Intraductal papillary mucinous neoplasm (IPMN), an increasingly recognized cystic neoplasm of the pancreas with a broad spectrum of malignant potential, has been considered a precursor to infiltrating ductal adenocarcinoma. Because of its unique clinical, radiological, pathological, and molecular features, IPMN has attracted considerable interest among clinicians and researchers. Although some genetic alterations have been described in IPMNs, the molecular features that characterize the evolution and progression of these neoplasms are largely unknown. Recent studies have shown that aberrant methylation of the promoter cytosine-phospho-guanine (CpG) island is a common mechanism associated with the silencing of tumor-suppressor and cancer-related genes in IPMNs. Importantly, the prevalence of such methylation increases along with the grade of neoplasia, suggesting that these epigenetic events may contribute to the progression of IPMNs. Further studies of epigenetic alterations in IPMN will shed light on the molecular pathogenesis of this unique neoplasm and lead to the identification of epigenetic markers that can be applied in the clinical setting.

Adenocarcinoma, Mucinous↗

PubMed2006

The role of epigenetic alterations in pancreatic cancer.

The past several years have witnessed an explosive increase in our knowledge about epigenetic features in human cancers. It has become apparent that pancreatic cancer is an epigenetic disease, as it is a genetic disease, characterized by widespread and profound alterations in DNA methylation. The introduction of genome-wide screening techniques has accelerated the discovery of a growing list of genes with abnormal methylation patterns in pancreatic cancer, and some of these epigenetic events play a role in the neoplastic process. The detection and quantification of DNA methylation alterations in pancreatic juice is likely a promising tool for the diagnosis of pancreatic cancer. The potential reversibility of epigenetic changes in genes involved in tumor progression makes them attractive therapeutic targets, but the efficacy of epigenetic therapies in pancreatic cancer, such as the use of DNA methylation inhibitors, remains undetermined. In this review, we briefly summarize recent research findings in the field of pancreatic cancer epigenetics and discuss their biological and clinical implications.

Cell Cycle Proteins↗

PubMed2006

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↗

PubMed2006

Pancreatic cancer genetic epidemiology consortium.

We have organized the Pancreatic Cancer Genetic Epidemiology (PACGENE) Consortium to identify susceptibility genes in familial pancreatic cancer (FPC). The Consortium comprises seven data collection centers, a statistical genetics core, and a pathology/archival genotyping core. We recruit kindreds containing two or more affected blood relatives ascertained through incident pancreatic adenocarcinoma cases, physician referrals, and/or through Internet recruitment. Accrual to a database containing core clinical, demographic, lifestyle, and family history information from questionnaires is ongoing, along with biospecimen collection. To date, 13,147 patients have been screened for family history, of whom 476 (50% male) probands and 1,912 of their adult (99% unaffected) relatives have been enrolled. Of these, 379 kindreds meet criteria for FPC, having at least two first-degree relatives with pancreatic cancer. Cumulative incidence curves using available age of diagnosis (onset) among and affected relatives were compared with those for incident pancreatic cancer cases reported to 13 U.S. Surveillance Epidemiology and End Results (SEER) sites from 1973 to 2000 (N = 72,700). The mean age +/- SD at diagnosis among 466 PACGENE probands and 670 affected relatives was 64.1 +/- 11.8 and was 65.4 +/- 11.6 for the subset of 369 FPC probands and 429 relatives. Both samples were significantly younger than the mean age at diagnosis in the SEER population (70.0 +/- 12.1 years; differences in curves versus SEER, P < 0.001). Age at diagnosis (excluding probands) in FPC kindreds does not decrease with increasing number of affected individuals. In our sample, younger age at diagnosis was observed whether we grouped probands by recruitment sites that predominantly recruited through high-risk referrals, or through screening all pancreatic cancer patients for family history. Linkage studies are ongoing. The PACGENE Consortium will be a valuable family-based resource that will greatly enhance genetic epidemiology research in pancreatic cancer.

Age of Onset↗

PubMed2006

Multifocal neoplastic precursor lesions associated with lobular atrophy of the pancreas in patients having a strong family history of pancreatic cancer.

We screened 116 patients with a strong family history of pancreatic cancer using a combination of endoscopic ultrasound and computed tomography. Ten of these patients underwent surgical resection at our institution, providing an opportunity to define the morphology of pancreatic precursor lesions in patients with a strong family history of pancreatic cancer. Eight of the 10 pancreata were available and these were entirely submitted for histologic examination. The number of pancreatic intraepithelial neoplasia (PanIN) lesions and intraductal papillary mucinous neoplasms (IPMNs) were compared with age-matched controls. Parenchymal changes were defined. Selected precursor neoplasms from 6 pancreata were microdissected and analyzed for KRAS gene mutations. PanINs were significantly more common in the 8 cases (mean of 10.7% of the duct profiles, range 1.0% to 27.3%) than in the controls (mean 1.9%, range 0% to 9.2%, P<0.01). Different KRAS gene mutations were identified in separately microdissected precursor lesions in 2 of 6 cases. IPMNs were identified in 4 of the 8 cases, including 2 pancreata each having 2 distinct IPMNs. Both the IPMNs and the PanINs, even the low-grade PanIN-1 lesions, were associated with lobular parenchymal atrophy. Some individuals with a strong family history of pancreatic cancer develop multifocal, noninvasive epithelial precursor lesions of the pancreas. PanINs and IPMNs produce obstructive lobular atrophy, and this atrophy is likely the source of the chronic pancreatitis-like changes seen in these patients. The multifocal nature of familial pancreatic neoplasia suggests that surveillance of these patients is warranted after partial pancreatectomy.

Adenocarcinoma, Mucinous↗

PubMed2005

Molecular markers of early pancreatic cancer.

Pancreatic cancer is a deadly disease and the fourth most common cause of cancer death in the United States. Since chemotherapy and radiotherapy have thus far largely failed to significantly improve the survival of patients with pancreatic ductal adenocarcinoma, there is considerable interest in identifying better diagnostic markers of pancreatic neoplasia. Not only could better markers improve the early diagnosis of pancreatic cancer and allow more patients to undergo curative surgical resection, but also could potentially be used for patients at high risk of developing pancreatic cancer to identify precancerous lesions while they are amenable to cure. A wealth of information has recently become available about gene expression, DNA methylation, and proteomics alterations that occur in pancreatic cancers creating hope that better diagnostic markers of pancreatic cancer will be soon forthcoming.

Biomarkers, Tumor↗

PubMed2005

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↗

PubMed2005

Increased cyclooxygenase-2 expression in duodenal compared with colonic tissues in familial adenomatous polyposis and relationship to the -765G -> C COX-2 polymorphism.

BACKGROUND: Colorectal cancers arising in patients with familial adenomatous polyposis (FAP) can be largely prevented by polyp surveillance and prophylactic colectomy. As a result, duodenal adenocarcinoma has become a leading cause of death in patients with FAP. Cyclooxygenase 2 (COX-2) inhibition is effective against colorectal polyposis in FAP, but is less effective in treating duodenal polyps. We compared the expression of COX-2 in duodenal and colorectal adenomas from patients with FAP and from patients with sporadic neoplasms and correlated expression to a COX-2 promoter polymorphism (-765G/-->C) that is reported to influence COX-2 expression. METHODS: The study population included 36 FAP patients with colonic adenomas, 22 FAP patients with duodenal adenomas, 22 patients with sporadic duodenal adenomas, and 17 patients with sporadic duodenal adenocarcinoma. Neoplastic and corresponding normal tissue COX-2 expressions were determined using immunohistochemistry on tissue microarrays. The prevalence and ethnic distribution of a polymorphism in the COX-2 promoter that influences COX-2 expression (-765G --> C) were determined in DNA from 274 individuals by real-time quantitative PCR. RESULTS: Among patients with FAP, histologically normal duodenal mucosa showed higher COX-2 expression than normal colonic mucosa (P < 0.02), and duodenal adenomas had higher COX-2 expression than colonic adenomas (P </= 0.01). In addition, the normal duodenum of patients with FAP showed higher COX-2 expression than the normal duodenal mucosa of patients with sporadic adenomas (P < 0.05). COX-2 expression was significantly higher in the normal-appearing (P < 0.01) mucosa of patients with FAP carrying the -765GG genotype compared with those carrying the -765GC or -765CC genotypes. The -765C genotype was more common in African Americans than in Caucasians (52% versus 33%, P < 0.01). CONCLUSIONS: High COX-2 expression in the normal and adenomatous duodenal mucosa of patients with FAP may explain the poorer response of these neoplasms to chemoprevention with COX-2 inhibitors.

Adenoma↗

PubMed2005

Increased prevalence of the BRCA2 polymorphic stop codon K3326X among individuals with familial pancreatic cancer.

Germline BRCA2 mutations predispose to the development of pancreatic cancer. A polymorphic stop codon in the coding region of BRCA2 (K3326X) has been described, and although an initial epidemiological study suggested it was not disease causing, subsequent studies have been inconclusive. To investigate the biological significance of the K3326X polymorphism, we determined its prevalence in patients with sporadic and familial pancreatic cancer. Using a case-control design, we studied 250 patients with resected sporadic pancreatic adenocarcinomas, 144 patients with familial pancreatic adenocarcinoma, 115 spouses of patients with pancreatic cancer, and a disease control group of 135 patients without a personal history of cancer who had undergone cholecystectomy for non-neoplastic disease. The K3326X polymorphism was detected using heteroduplex analysis and DNA sequencing. The BRCA2 K3326X polymorphism was significantly more prevalent in individuals with familial pancreatic cancer: 8/144 (5.6%) vs 3/250 controls (1.2%) (odds ratio, 4.84; 95% CI, 1.27-18.55, P<0.01). One K3326X carrier with familial pancreatic cancer carried an alteration (IVS 16-2A>G) suspected to be deleterious. Excluding this case did not alter the significance of the association (OR: 4.24, P<0.01). In contrast, there was no difference in prevalence among individuals with sporadic pancreatic cancer - 7/250 (OR: 2.37, 95% CI: 0.61-9.27). The increased prevalence of the BRCA2 K3326X polymorphism in patients with familial pancreatic cancer suggests that this polymorphism is deleterious and contributes to pancreatic cancer risk.

Adenocarcinoma↗

PubMed2005

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↗