Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149521 (chronic pancreatitis)
 7,199 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pancreatic adenocarcinoma is believed to develop from histologically identifiable intraductal lesions known as pancreatic intraepithelial neoplasias (PanINs) that undergo a series of architectural, cytologic, and genetic changes, a progression model similar to the adenoma-carcinoma sequence in the colon. The apomucin MUC4 has been implicated in invasive pancreatic adenocarcinoma. MUC4 expression is not detectable at the RNA level in normal pancreas but is detectable at high levels in invasive pancreatic adenocarcinoma. We documented the pattern of expression of MUC4 in PanINs by studying a series of 71 PanIN lesions immunohistochemically using a new monoclonal antibody to MUC4. Five (17%) of 30 PanIN-1 lesions, 10 (36%) of 28 PanIN-2 lesions, 11 (85%) of 13 PanIN-3 lesions, and 25 (89%) of 28 invasive adenocarcinomas labeled with the MUC4 antibody used in the study. In addition, afew nonneoplastic lesions labeled with the MUC4 antibody, including reactive ducts in chronic pancreatitis, atrophic ducts filled with inspissated secretions, and ducts showing squamous metaplasia. Our data help establish the patterns of MUC4 expression in neoplastic precursors in the pancreas and add further support to the progression model for pancreatic adenocarcinoma.
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PMID:MUC4 expression increases progressively in pancreatic intraepithelial neoplasia. 1209 Apr 30

A multistep model of carcinogenesis has recently been proposed for pancreatic ductal adenocarcinomas. In this model, noninvasive precursor lesions in the pancreatic ductules accumulate genetic alterations in cancer-associated genes eventually leading to the development of an invasive cancer. The nomenclature for these precursor lesions has been standardized as pancreatic intraepithelial neoplasia or PanIN. Despite the substantial advances made in understanding the biology of invasive pancreatic adenocarcinomas, little is known about the initiating genetic events in the pancreatic ductal epithelium that facilitates its progression to cancer. Telomeres are distinctive structures at the ends of chromosomes that protect against chromosomal breakage-fusion-bridge cycles in dividing cells. Critically shortened telomeres can cause chromosomal instability, a sine qua non of most human epithelial cancers. Although evidence for telomeric dysfunction has been demonstrated in invasive pancreatic cancer, the onset of this phenomenon has not been elucidated in the context of noninvasive precursor lesions. We used a recently described in situ hybridization technique in archival samples (Meeker AK, Gage WR, Hicks JL, Simon I, Coffman JR, Platz EA, March GE, De Marzo AM: Telomere length assessment in human archival tissues: combined telomere fluorescence in situ hybridization and immunostaining. American Journal of Pathology 2002, 160:1259-1268) for assessment of telomere length in tissue microarrays containing a variety of noninvasive pancreatic ductal lesions. These included 82 PanIN lesions of all histological grades (24 PanIN-1A, 23 PanIN-1B, 24 PanIN-2, and 11 PanIN-3) that were selected from pancreatectomy specimens for either adenocarcinoma or chronic pancreatitis. Telomere fluorescence intensities in PanIN lesions were compared with adjacent normal pancreatic ductal epithelium and acini (62 of 82 lesions, 76%), or with stromal fibroblasts and islets of Langerhans (20 of 82 lesions, 24%). Telomere signals were strikingly reduced in 79 (96%) of 82 PanINs compared to adjacent normal structures. Notably, even PanIN-1A, the earliest putative precursor lesion, demonstrated a dramatic reduction of telomere fluorescence intensity in 21 (91%) of 23 foci examined. In chronic pancreatitis, reduction of telomere signal was observed in all PanIN lesions, whereas atrophic and inflammatory ductal lesions retained normal telomere length. Telomere fluorescence intensity in PanIN lesions did not correlate with proliferation measured by quantitative Ki-67-labeling index or topoisomerase IIalpha expression. Thus, telomere shortening is by far the most common early genetic abnormality recognized to date in the progression model of pancreatic adenocarcinomas. Telomeres may be an essential gatekeeper for maintaining chromosomal integrity, and thus, normal cellular physiology in pancreatic ductal epithelium. A critical shortening of telomere length in PanINs may predispose these noninvasive ductal lesions to accumulate progressive chromosomal abnormalities and to develop toward the stage of invasive carcinoma.
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PMID:Telomere shortening is nearly universal in pancreatic intraepithelial neoplasia. 1241 2

Patients with long-standing chronic pancreatitis are thought to be at increased risk of developing pancreatic ductal adenocarcinoma, but the mechanism for this increased risk is unknown. Since increasing evidence supports the notion that infiltrating pancreatic ductal adenocarcinomas arise from pancreatic intraepithelial lesions (PanINs), we sought to determine if patients with chronic pancreatitis harbor PanINs with alterations in tumor suppressor genes that are associated with infiltrating pancreatic ductal adenocarcinoma. We identified 122 patients with a diagnosis of chronic pancreatitis and 29 patients with a well-differentiated pancreatic endocrine tumor that underwent pancreatic surgery at the Johns Hopkins Hospital from 1985 to 1999. PanINs from each resection specimen were identified, graded, counted, and correlated with smoking and alcohol history. The expression patterns of p16 and Smad4 were determined in a subset of PanINs by immunohistochemistry, and the pattern of labeling compared with that seen in PanINs associated with infiltrating adenocarcinoma of the pancreas as identified in prior studies, and to PanINs associated with pancreatic endocrine tumor. Duct lesions were present in 80 of the 122 pancreata with chronic pancreatitis (66%). Of 405 duct lesions identified in the chronic pancreatitis group, 7.6% were reactive changes, 65.5% were PanIN-1A, 18% were PanIN-1B, 7.4% were PanIN-2, and 1.5% were PanIN-3. Within the pancreatic endocrine tumor group, 22 PanINs were identified: 15 PanIN-1A, 4 PanIN-1B, and 3 PanIN-2. There were significantly fewer high-grade PanINs in the pancreata with chronic pancreatitis than in pancreata with pancreatic adenocarcinoma (P < 0.0001). Within the chronic pancreatitis group, the 80 patients with PanINs were significantly older than the 42 patients without PanINs (mean age 57.0 +/- 14.1 years vs. 50.9 +/- 14.7 years, P = 0.01). Smoking history was not associated with PanIN prevalence or grade, but patients who reported a history of excessive alcohol consumption had fewer PanINs (25 of 44 harbored PanINs, 57%) than those who did not (54 of 74, 73%, P = 0.07). In the chronic pancreatitis group, 0% of PanIN-1A, 11% of the PanIN-1B, 16% of the PanIN-2, and 40% of the PanIN-3 lesions showed loss of p16 expression, whereas all of the PanINs from patients with an pancreatic endocrine tumor retained p16 expression. All of the PanINs analyzed from patients with chronic pancreatitis retained normal Smad4 expression. We conclude that a significant minority of PanINs arising in patients with chronic pancreatitis show loss of p16 expression. This alteration, common to pancreatic cancer-associated PanINs, may contribute to the predisposition of patients with chronic pancreatitis to develop pancreatic ductal adenocarcinoma.
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PMID:p16 Inactivation in pancreatic intraepithelial neoplasias (PanINs) arising in patients with chronic pancreatitis. 1465 8

Patients with chronic pancreatitis have a markedly increased risk of pancreatic cancer compared with general population. Mechanism of the increased risk is not completely known. The current progression model for pancreatic ductal adenocarcinoma proposes the progression from normal ductal epithelium through a series of lesions called pancreatic intraepithelial neoplasias (PanINs) to invasive cancer. These lesions are frequently seen in chronic pancreatitis tissue. Proliferative activity in PanINs of chronic pancreatitis tissue has not been separately studied using the current nomenclature. Our study included 36 chronic pancreatitis resection specimens. A total number of 106 PanINs found within 32 resection specimens was histologically graded and then immunolabeled using a monoclonal antibody against Ki-67 that is expressed in dividing cells. The Ki-67 labeling indices in the increasing grades of PanINs were counted with following results: PanIN-1A, 0.77%; PanIN-1B, 3.26%; PanIN-2, 14.68%; and PanIN-3, 25.4%. The difference in Ki-67 labeling indices among these types of lesions was statistically significant (p<0.001, t-test). These results correlate with known genetic alterations found in chronic pancreatitis, especially with p16 inactivation that was recently described in PanINs arising in patients with chronic pancreatitis. Moreover, our findings support the currently accepted pancreatic progression model and Ki-67 immunohistochemistry might represent an efficient tool for an identification of a high-risk lesion.
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PMID:Proliferative activity in pancreatic intraepithelial neoplasias of chronic pancreatitis resection specimens: detection of a high-risk lesion. 1564 Sep 47

Pancreatic cancer is a highly malignant tumor. In this study, we examined the association between the expression of MUC1, MUC2, MUC5AC, and E-cadherin, and the pathological changes from normal pancreatic tissue to invasive ductal carcinoma(IDC). Since MUC1 is known to be involved in the inhibition of E-cadherin, we also examined the association between MUC1 and E-cadherin. Five normal pancreatic tissues, 6 chronic pancreatitis tissues, 20 pancreatic intraepithelial neoplasia (PanIN) tissues, and 24 IDC tissues were fixed in formalin, embedded in paraffin, and sections were immunostained. MUC1 was positive in nonneoplastic tissues, PanIN-3, and IDC. MUC2 was negative in almost all tissues. MUC5AC was positive in neoplastic tissues. E-cadherin was positive in almost all tissues. Changes in MUC1 staining were observed in PanIN-3 and IDC, and E-cadherin staining was seen in neoplastic tissues. MUC1 was more diffusely positive in lymph node metastasis-positive cases. The expression of MUC1 and MUC5AC is associated with the progression of PanIN. MUC1 may promote the inhibition of E-cadherin. The results also suggest that MUC1 is useful as a prognostic marker.
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PMID:Immunohistochemical study of the association between the progression of pancreatic ductal lesions and the expression of MUC1, MUC2, MUC5AC, and E-cadherin. 1678 13

A disintegrin and metalloproteinase (ADAM) molecules are known for their unique potential to combine adhesion, proteolysis, and signaling. To understand the role of ADAM17/tumor necrosis factor-alpha (TNF-alpha) converting enzyme (TACE) in pancreatic ductal adenocarcinoma (PDAC), we investigated its expression, function, and in vitro regulation. ADAM17/TACE mRNA was expressed in 3 of 10 normal pancreatic tissues, 6 of 8 samples from patients with chronic pancreatitis, 10 of 10 PDAC tissues, and 9 of 9 pancreatic cancer cell lines, but it was absent in primary duct epithelial cells. Immunohistochemical staining revealed positive cancer cells in 8 of 10 PDACs but no staining of ducts in normal pancreas. ADAM17/TACE was found in 0 of 16 pancreatic intraepithelial neoplasia (PanIN)-1A lesions, 1 of 30 PanIN-1B lesions, 2 of 13 PanIN-2 lesions but, in 13 of 15 PanIN-3 lesions, associated with PDAC. Western blot, flow cytometry, and confocal microscopy analyses showed the aberrant expression of ADAM17/TACE protein in pancreatic cancer cell lines. The proteolytic activity of ADAM17/TACE, assessed by the release of TNF-alpha, was inhibited by TNF-alpha protease inhibitor. ADAM17/TACE gene silencing using small interfering RNA technique in vitro reduced invasion behavior dramatically, whereas proliferation was unaffected. Furthermore, ADAM17/TACE mRNA expression was down-regulated in pancreatic cancer cells arrested in G2-M phase as well as in a time-dependent manner after TNF-alpha and interleukin-6 incubation. In conclusion, our findings provide evidence of aberrant expression of the proteolytically active ADAM17/TACE in advanced precursor lesions (PanIN-3) and PDAC while identifying its critical involvement in the invasion process.
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PMID:Aberrant expression of a disintegrin and metalloproteinase 17/tumor necrosis factor-alpha converting enzyme increases the malignant potential in human pancreatic ductal adenocarcinoma. 1698 46

Morphologic, clinical, and genetic evidence suggests that pancreatic intraepithelial neoplasia (PanIN) is a precursor to ductal adenocarcinoma. But understanding precursor lesions in a pancreas with existing tumor is hampered by the fact that chronic pancreatitis often accompanies carcinoma, and the possible interactions between tumor, chronic pancreatitis, and PanIN are complex. Furthermore, cancerization of ducts can mimic high-grade PanIN. Heterotopic pancreas has a genetic make-up, physiologic function, and local environmental exposure similar to that of the pancreas. It offers an opportunity to study putative precursor lesions in a setting with fewer confounding factors. We identified 6 pancreatic cancer patients who had heterotopic pancreas removed at the time of surgery. All 6 cases were immunostained for p53, cyclin D1, and p16. Molecular analysis of K-ras mutation was also done. All 6 cancer-associated heterotopias had PanIN-1A or 1B; 5 had PanIN-2 and 1 had PanIN-3. Three of 6 cases harbored the same K-ras codon 12 mutation as the PanINs in orthotopic pancreas, and a similar pattern of p53, cyclin D1, and p16 expression was observed between heterotopic and orthotopic pancreas in all 6 cases. There was no chronic pancreatitis in the cancer-associated heterotopias, but chronic pancreatitis was seen adjacent to carcinoma in 5 of 6 cases. The presence of PanIN in heterotopic pancreas from patients with ductal adenocarcinoma supports the progression model.
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PMID:Pancreatic intraepithelial neoplasia in heterotopic pancreas: evidence for the progression model of pancreatic ductal adenocarcinoma. 1766 42

Identification of high-risk individuals, genetic counseling, and informed consent are important components of a screening program for familial pancreatic cancer. Screening high-risk individuals with imaging tests, such endoscopic ultrasound (EUS) and computed tomography (CT), can lead to the detection and treatment of predominantly asymptomatic early pancreatic neoplasms, as well as extra-pancreatic tumors. These pancreatic neoplasms consist of resectable, mostly branch-type non-invasive intraductal papillary mucinous neoplasms (IPMNs). EUS can visualize these very early IPMNs as focal duct ectasias or cysts. EUS features of chronic pancreatitis are highly prevalent in high-risk individuals and these directly correlate with multifocal lobulocentric parenchymal atrophy due to multifocal pancreatic intraepithelial neoplasia (PanIN). No one molecular marker is ready for "prime time" screening of high-risk individuals. Translational studies are underway to discover novel biomarkers for IPMNs, PanIN-3 lesions, or microinvasive adenocarcinoma, which are likely to be cured by timely intervention. Long-term, multi-prospective studies are needed to determine if screening for early pancreatic neoplasia and timely intervention results in decreased pancreatic cancer incidence and mortality in high-risk individuals.
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PMID:Strategies for screening for pancreatic adenocarcinoma in high-risk patients. 1767 57

The clinical significance of pancreatic intraepithelial neoplasia (PanIN) lesions in non-neoplastic pancreata of pancreatic ductal adenocarcinoma (PDAC) patients remains controversial. As chronic inflammation has been recently demonstrated to promote dissemination of in situ precancerous lesions, we investigated the prognostic significance of PanINs associated with chronic pancreatitis (CP) in PDAC patients. This retrospective study analyzed 125 curatively resected PDAC specimens for the presence of PanIN and CP. Univariate and multivariate analyses were performed to identify significant predictive factors for poor disease-free survival (DFS) and overall survival (OS). Immunohistochemical staining for E-cadherin and S100A4, markers of epithelial-mesenchymal transition, was performed on resected specimens containing PanIN-3 lesions. CP was observed in 27.2% (34/125) and PanIN-3 in 25.6% (32/125) of specimens. In the presence of CP, PanIN-3 was significantly associated with decreased survival (DFS: 4.3 vs 15.5 months, P = 0.021; OS: 16.3 vs 30.9 months, P = 0.004). PanIN-3 was not a prognostic factor in the absence of CP. The presence of both PanIN-3 and CP was associated with a reduced survival compared to the other cases, in both univariate (DFS: P = 0.039; OS: P = 0.023) and multivariate (DFS: P = 0.020; OS: P = 0.076) analyses. Furthermore, E-cadherin loss and S100A4 expression were more frequently observed in PanIN-3 lesions of CP specimens than in those of non-CP specimens, although not statistically significant. PanIN-3 in association with CP is a significant prognostic factor for decreased survival in PDAC patients, suggesting that chronic inflammation may accelerate the progression of preinvasive high-grade PanIN.
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PMID:Presence of pancreatic intraepithelial neoplasia-3 in a background of chronic pancreatitis in pancreatic cancer patients. 2618 80

Background: The risk of developing invasive cancer in the remnant pancreas after resection of multifocal high-grade pancreatic precursor lesions is not well known. We report three patients who were followed up after resection of multifocal high-grade pancreatic intraepithelial neoplasia (PanIN)-3 or intraductal papillary mucinous neoplasia (IPMN), two of whom eventually developed invasive carcinoma. Presentation: 1) 68-year-old woman who had a laparoscopic distal pancreatectomy for multifocal mixed-type IPMN, identified as high-grade on final pathology, with negative surgical margins. During semiannual monitoring, eight years from the first surgery, the patient developed suspicious features prompting surgical resection of the body with final pathology revealing invasive ductal adenocarcinoma in the setting of IPMN. 2) 48-year-old woman who had a distal pancreatectomy for severe acute/chronic symptomatic pancreatitis, with final pathology revealing multifocal high-grade PanIN-3, with negative surgical margins. Despite semiannual monitoring, two years from the first surgery, the patient developed pancreatic adenocarcinoma with liver metastasis. 3) 55-year-old woman who had a Whipple procedure for symptomatic chronic pancreatitis, with multifocal PanIN-3 on final pathology. The patient underwent completion pancreatectomy due to symptomatology and her high-risk profile, with final pathology confirming multifocal PanIN-3. Conclusion: Multifocal high-grade dysplastic lesions of the pancreas might benefit from surgical resection.
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PMID:Multifocal High-Grade Pancreatic Precursor Lesions: A Case Series and Management Recommendations. 3128 90


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