Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasminogen activators (PAs) play an important role in tumor cell invasion. We have analysed the expression of tissue-type PA (t-PA), urokinase-type PA (u-PA), and their respective receptors, annexin II and u-PAR, in normal and neoplastic cultures of pancreatic cells, as well as in pancreatic tissues, and have examined their role in tumor invasiveness in vitro. Using Northern blotting, Western blotting, and ELISA, t-PA is detected in cultured pancreas cancer cells displaying a well differentiated phenotype but it is undetectable in less differentiated cells and in normal pancreatic cultures. In contrast, u-PA transcripts, protein, and enzymatic activity are detected both in cancer cells and in normal cultures. Higher levels of u-PAR and annexin II are present in cancer cells than in normal cultures and, in SK-PC-1 cells, both receptors are localized in the basolateral membrane. In vitro invasion assays indicate that both t-PA and u-PA contribute to the invasiveness of SK-PC-1 cells through reconstituted extracellular matrix. To determine the relevance of these studies to pancreas cancer, immunohistochemical assays have been used to examine the expression of t-PA, u-PA, and their receptors in normal and neoplastic tissues. t-PA is absent from normal pancreas and from tumor associated pancreatitis, whereas it is detected in the majority of pancreas cancer tissues (16/17). Annexin II is also overexpressed in some tumors (5/13). u-PAR is overexpressed in most tumor samples examined (14/15), while u-PA is weakly detected in a low number of cases (3/14); both u-PAR and u-PA are overexpressed in areas of tumor associated pancreatitis. Indirect evidences indicate that K-ras and p53 mutated proteins can regulate the expression of PAs. In pancreatic cancer we have found an association between codon 12 K-ras mutations and t-PA expression (P=0.04). These results support the contention that, in the exocrine pancreas, activation of t-PA is more specifically associated to neoplastic transformation and to the invasive phenotype, whereas the induction of u-PA/u-PAR system might be more relevant to inflammatory or non-neoplastic events.
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PMID:The plasminogen activator system in pancreas cancer: role of t-PA in the invasive potential in vitro. 948 8

Epidemiologic studies on exocrine pancreatic cancer show a large heterogeneity in diagnostic criteria applied to define "caseness." Reanalyses conducted after review of diagnostic information have yielded substantially different results than those based on more crude classifications of disease. During a multicenter prospective study on mutations in the K-ras gene in pancreatic and biliary diseases, hospital diagnoses from 602 patients were reviewed by a panel of experts. There were two main motivations to do so: a generic interest for the quality of the diagnostic data, and the anticipation that a firm diagnosis could be needed to assess whether patients whose tumors did not harbor the mutation were true negatives or false negatives. In addition, the review of diagnoses was helpful to minimize tissue misclassification, and it had a high educational value for clinicians and epidemiologists. This article illustrates why and how this was so through a brief presentation of the 10 most significant cases. With respect to selection and classification of subjects, the main issues that studies on pancreatic cancer need to address are the differential diagnosis of exocrine pancreatic cancer and pancreatitis, the differential diagnosis of exocrine pancreatic cancer and other abdominal tumors, and the use of survival as a hallmark of pancreatic cancer. In epidemiologic studies of pancreatic cancer, it is warranted that a panel of experts centrally reviews all the existing diagnostic evidence (cytohistological and other) of all patients, regardless of whether they have cytohistological confirmation and of their hospital discharge diagnosis.
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PMID:Learning from case reports: diagnostic issues in an epidemiologic study of pancreatic cancer. 1008 13

Pancreatic carcinoma is the fourth cause of death for cancer in the USA, carrying a dismal prognosis and poor overall survival. Unfortunately, resection for cure is feasible in a limited number of patients, thus confirming the need for an early diagnosis and accurate preoperative staging to select patients potentially resectable from those candidates to palliative treatment. Among imaging modalities, endoscopic procedures (endoscopic retrograde cholangiopancreatography, laparoscopy and endoscopic ultrasonography) play a key role in the diagnosis and staging of pancreatic tumors. Endoscopic retrograde cholangiopancreatography (ERCP) allows direct visualization of the main pancreatic duct and its side branches with their morphologic alterations, which are present in most cases of pancreatic cancer. The method is very sensitive in experienced hands, with diagnostic accuracy over 95%. The most common finding in pancreatic cancer is the stricture of the pancreatic duct, the bile duct, or both. Moreover, ductal brush cytology and K-ras mutation analysis can be performed during ERCP, possibly improving the diagnostic accuracy of the technique. Diagnostic laparoscopy provides detection of small (< 1 cm) liver metastases and peritoneal implants of tumor which cannot be visualized by any other imaging modality, with the possibility to biopsy under direct vision suspicious areas or to perform peritoneal lavage. The adjunct of laparoscopic ultrasound improves the staging capabilities of the technique for pancreatic cancer (retroperitoneal spread, vascular invasion). Endoscopic ultrasonography (EUS) is able to produce great detail of the pancreatic parenchyma and regional lymph nodes. It is especially sensitive in the detection of small pancreatic masses which cannot be imaged with other modalities. EUS has the additional advantage of directing transduodenal fine-needle aspiration biopsies. Presently it is the most sensitive technique for the diagnosis and locoregional staging of pancreatic cancer, but limits have been identified in the lack of specificity (differentiation between malignant tumor and focal pancreatitis) and its operator-dependency. Reported is our experience with EUS in the diagnosis and staging of pancreatic cancer. Over a seven-year period 43 patients with pancreatic tumors were staged with EUS preoperatively. Twenty-two patients were submitted to surgery at our Institution and EUS findings were compared with results of pathology or surgical exploration. EUS provided sensitivity of 100% for the diagnosis of pancreatic cancer, while its accuracy for staging tumor infiltration, lymph node involvement and vascular invasion was 86.4%, 69.2% and 77.8%, respectively. Despite improvements in the noninvasive imaging modalities, endoscopic techniques are likely to remain established methods for the diagnosis and staging of pancreatic cancer. EUS with fine-needle aspiration biopsy is probably the most promising, followed by laparoscopy (and laparoscopic ultrasound) which is essential to rule out small peritoneal implants and liver metastasis.
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PMID:[Endoscopy in the diagnosis and staging of pancreatic cancer]. 1023 74

Biliopancreatic malignancy is one of the leading causes of cancer death in the Western world. Defining at risk groups has been difficult. Diabetes mellitus and pancreatitis increase the risk of pancreatic carcinoma, and inflammatory bowel disease and associated sclerosing colangitis increase the risk of biliary tract malignancy. Pancreatic carcinoma has also been described in pedigrees with inherited cancer predisposition. Extensive molecular profiling of pancreatic carcinomas has been accomplished over the past few years, but similar knowledge in other biliopancreatic malignancies is lacking. In almost all pancreas cancers at least one alteration will occur out of a combination of K-ras mutations and inactivation of the tumor suppressor genes p16/MTS1/ink4a, p53 and DPC4/Smad4. Mutations of K-ras and p16 have been described in hyperplastic and dysplastic pancreatic ductal lesions believed to be the non-malignant precursors of pancreatic carcinoma. Detection of K-ras mutations in clinical samples (biliopancreatic secretions, stool, duodenal aspirates, and blood) identical to ones present in primary pancreatic cancers and/or their precursor ductal lesions has been reported in pilot studies. Recently detection of 18q deletions (at the DPC4 locus) in pancreatic secretions from early pancreatic cancers was also reported. These advances raise the possibility that within well defined at risk groups it will be possible to use a combined set of molecular markers to screen clinical samples and detect early pancreatic cancer or even pre-malignant lesions. The fulfillment of this promise will depend on proving the role of molecular screening in decreasing morbidity and mortality, which will require well designed clinical studies.
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PMID:Biliopancreatic malignancy: screening the at risk patient with molecular markers. 1043 11

Clinically, differential diagnosis of pancreatic carcinoma (PC) and so-called "mass-forming pancreatitis (MFP)" is difficult. We analyzed the amount, ductal level, and K-ras mutation of ductal hyperplasia and intraductal carcinoma in surgically resected cases of MFP (n = 18) and PC (n = 16). DNAs extracted from microdissected epithelial foci were analyzed for K-ras codon 12 mutation by nested polymerase chain reaction and restriction fragment length polymorphism. The histology of MFP showed severe destruction of exocrine tissue and pancreatic stones and/or protein plugs (72%, 13 of 18 cases) in mostly peripheral ducts. The average basal membrane lengths of nonpapillary and papillary hyperplasia in cases of carcinoma were about 4 and 15 times more than those of MFP, respectively. The frequency of K-ras mutation in hyperplastic foci increased from nonpapillary [six (27%) of 22] to papillary foci [16 (64%) of 25] in K-ras mutant PCs, but there was no difference between nonpapillary [one (6%) of 18] and papillary foci (none of 19) in K-ras wild-type PCs, and also between nonpapillary (none of 24) and papillary foci [one (7%) of 14] in MFPs.
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PMID:Different amounts of K-ras mutant epithelial cells in pancreatic carcinoma and mass-forming pancreatitis. 1088 36

Adenoma and adenocarcinoma of the ampulla of Vater are uncommon neoplasms of the gastrointestinal tract. Only one report has analyzed the relationship between ampullary adenocarcinoma and pancreatic intraductal neoplasia (PanIN), the precursor lesion of pancreatic adenocarcinoma. An association between PanIN and ampullary adenoma has not been reported previously. Case reports have documented the progression of PanIN to invasive pancreatic adenocarcinoma. We reviewed five resected ampullary adenoma and 17 ampullary adenocarcinoma cases and evaluated the pancreas for PanIN. Pancreatic sections from 35 autopsies were reviewed as a control group. Immunohistochemistry for overexpression of p53 and COX-2 proteins was performed in selected cases, as was PCR analysis for K-ras mutations. Follow-up clinical data were obtained. All 22 ampullary neoplasms were associated with PanIN, which was high grade in two (40%) adenoma cases and seven (41%) adenocarcinoma cases. In 16 (73%) evaluable cases, PanIN extended to the pancreatic resection margin; two of which had high grade PanIN. Among the autopsy controls eight (23%) had low-grade PanIN. Seven of the 22 ampullary cases but none of the autopsy controls had coexistent pancreatitis. A smoking history was present in two of four autopsy cases in which this history was available. Overexpression of the p53 and COX-2 proteins was present in only one case of high-grade PanIN. K-ras mutations were present in four of four of the PanIN lesions evaluated, including one autopsy case. Clinical follow-up revealed no progression of PanIN to invasive carcinoma in the remnant pancreas, although the follow-up period was too short to adequately assess that risk (an average of 3.8 y for adenoma cases and 2.5 y for adenocarcinoma cases). We conclude that adenomas and carcinomas of the ampulla are associated with PanIN, and often high-grade PanIN. Although its malignant potential has not been fully established, PanIN is underreported and often unrecognized. PanIN may be analogous to colorectal adenoma in that both are prevalent in the older adult population, but few progress to carcinoma.
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PMID:Neoplasms of the ampulla of vater with concurrent pancreatic intraductal neoplasia: a histological and molecular study. 1126 17

The prevalence of pancreatic cancer in the general population is too low--even in high-prevalence areas such as Northern Europe and North America (8-12 per 10(5) population)--relative to the diagnostic accuracy of present detection methods to permit primary screening in the asymptomatic adult population. The recognition that the lifetime risk of developing pancreatic cancer for patients with hereditary pancreatitis (HP) is extremely high (20% by the age of 60 years and 40% by the age of 70 years) poses considerable challenges and opportunities for secondary screening in those patients without any clinical features of pancreatic cancer. Even for secondary screening, the detection of cancer at a biological stage that would be amenable to cure by surgery (total pancreatectomy) still requires diagnostic modalities with a very high sensitivity and specificity. Conventional radiological imaging methods such as endoluminal ultrasound and endoscopic retrograde pancreatography, which have proved to be valuable in the early detection of early neoplastic lesions in patients with familial pancreatic cancer, may well be applicable to patients with HP but only in those without gross morphological features of chronic pancreatitis (other than parenchymal atrophy). Unfortunately, most cases of HP also have associated gross features of chronic pancreatitis that are likely to seriously undermine the diagnostic value of these conventional imaging modalities. Pre-malignant molecular changes can be detected in the pancreatic juice of patients. Thus, the application of molecular screening in patients with HP is potentially the most powerful method of detection of early pancreatic cancer. Although mutant (mt) K-ras can be detected in the pancreatic juice of most patients with pancreatic cancer, it is also present in patients with non-inherited chronic pancreatitis who do not progress to pancreatic cancer (at least in the short to medium term), as well as increasingly in the older population without pancreatic disease. Nevertheless, the presence of mt-K-ras may identify a genuinely higher-risk group, enabling additional diagnostic imaging and molecular resources to be focussed on such a group. What is clear is that prospective multi-centre studies, such as that being pursued by the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer (EUROPAC), are essential for the development of an effective secondary screening programme for these patients.
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PMID:Molecular diagnosis of early pancreatic ductal adenocarcinoma in high-risk patients. 1212 Feb 29

This paper overviewed risk factors of pancreatic cancer. Both genetic and environmental factors may be playing significant roles in the development of pancreatic cancer. Cigarette smoking has been established as a major risk factor for pancreatic cancer, based on findings from almost all epidemiological studies. Long-term smoking cessation may reduce the risk. The evidence that alcohol drinking and coffee consumption increase the risk is not sufficient, although an association with higher level of consumption remains a possibility. Diabetes mellitus, long-standing diabetes in particular, may be a risk factor for pancreatic cancer. Individuals with hereditary pancreatitis or non-hereditary chronic pancreatitis are possibly at increased risk of pancreatic cancer. Higher intake of meat and fat may be associated with an increased risk, while consumption of fruits/vegetables appears to have a protective effect. Individuals with mutations or deletion in such genes as K-ras, p16, p53, DPC4, and BRCA2 increased the risk of developing pancreatic cancer. Cigarette smoking may play a role in the development of these mutations.
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PMID:An Epidemiological Overview of Environmental and Genetic Risk Factors of Pancreatic Cancer. 1271 18

Recently, we have characterized the Ras association domain family 1A gene (RASSF1A) at the segment 3p21.3, which is frequently lost in variety of human cancers and epigenetically inactivated in many types of primary tumors, such as lung, breast, kidney, prostate and thyroid carcinomas. Here, we investigated the methylation status of the RASSF1A CpG island promoter in the pathogenesis of pancreatic cancer. RASSF1A hypermethylation was detected in 29 out of 45 (64%) primary adenocarcinomas, in 10 out of 12 (83%) endocrine tumors and in eight out of 18 (44%) pancreatitis samples. In seven out of eight pancreas cancer cell lines, RASSF1A was silenced and was retranscribed after treatment with 5-aza-2'-deoxycytidine. Additionally, we analysed the aberrant methylation frequency of cell cycle inhibitor p16(INK4a) and K-ras gene mutations in the pancreatic samples. p16 inactivation was detected in 43% of adenocarcinomas, in 17% of neuroendocrine tumors, in 18% of pancreatitis and in 63% of pancreas cancer cell lines. K-ras mutations were detected in 16 out of 45 (36%) primary adenocarcinomas. Pancreatic adenocarcinomas with K-ras mutation have significantly less RASSF1A methylation and vice versa (P=0.001, chi(2) test). In conclusion, our data indicate that inactivation of the RASSF1A gene is a frequent event in pancreatic cancer and suggest an inverse correlation between RASSF1A silencing and K-ras activation.
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PMID:Frequent RASSF1A promoter hypermethylation and K-ras mutations in pancreatic carcinoma. 1280 88

IgG4-related sclerosing disease is a systemic disease histologically characterized by extensive T lymphocytes and IgG4-positive plasma cell infiltration of various organs. Major clinical manifestations are apparent in the pancreas (autoimmune pancreatitis), bile duct (sclerosing cholangitis), gallbladder (sclerosing cholecystitis), salivary gland (sclerosing sialadenitis), and retroperitoneum (retroperitoneal fibrosis), in which tissue fibrosis with obliterative phlebitis is pathologically induced. Autoimmune pancreatitis is a pancreatic lesion and its extrapancreatic lesions are organs reflecting an IgG4-related sclerosing disease. In some cases, only one or two organs are clinically involved, while in others three or four organs are affected. The disease occurs predominantly in elderly males, is frequently associated with lymphadenopathy, and responds well to steroid therapy. Since malignant tumors are frequently suspected on initial presentation, IgG4-related sclerosing disease should be considered in the differential diagnosis to avoid unnecessary surgery. Some cases of autoimmune pancreatitis were reportedly associated with pancreatic cancer. Although no relationship between the two diseases is known, we showed frequent and significant K-ras mutations in the pancreas, the bile duct, and the gallbladder in autoimmune pancreatitis.
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PMID:[IgG4-related sclerosing disease, including its relation to carcinogenesis]. 2140 35


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