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

Epidemiological studies show that smokers are at a significantly higher (70%) risk of getting affected by chronic pancreatitis and tumours of pancreas than non-smokers. The aim of the study was to assess the effect of cigarette smoking on the expression of gene p53 in pancreas by defining immunohistochemical localization of p53 protein in tissue specimens of the pancreases derived from healthy persons and smoking and non-smoking patients with diagnosed chronic pancreatitis (CP). Patients underwent surgery in which tissue material was collected. Immunohistochemical localization of 53 protein in paraffin tissue specimens of the pancreas was performed using the LSAB2-HRP visual test (DAKO K0673) with monoclonal p53 protein (DAKO N1581) antibodies. Exposure to tobacco smoke was assessed by determining cotinine in the patients' serum using the ELISA method. The study revealed a expression of p53 protein in smoking CP patients. In non-smoking patients and healthy persons wasn't showed expression of protein. Smoking patients above the twenty cigarettes for day showed significantly higher expression of p53 protein in the pancreas compared to smoking patients less. Cigarette smoking increases the expression p53 protein in pancreas of smoking patients with chronic pancreatitis. Impairment of the gene p53 in pancreas is frequently manifested by complications in pancreatitis resulting among others from long-term smoking, and conducted by tumour proliferation.
 ...
PMID:[Immunohistochemical localization of p53 protein in smoking patients with chronic pancreatitis]. 1728 89

The objective of this study was to explore the pathophysiological relevance of WISP-2/CCN5 in progression of human pancreatic adenocarcinoma (PAC). We found WISP-2/CCN5 mRNA and protein expression was faint and sporadic in PAC and detected in only 8.7-20% of the samples with varying grades as compared to adjacent normal and chronic pancreatitis samples where expression was very high in the ducts and acini. Colocalization studies in tissue-microarray slides revealed WISP-2/CCN5 mRNA loss was associated with p53 overexpression in PAC. Like tissue samples, p53 mutant-PAC cell lines show loss of WISP-2/CCN5. Moreover, functional analysis studies demonstrate exposure of pancreatic cancer cells to WISP-2/CCN5 recombinant protein enhances mesenchymal-epithelial-transition (MET). Collectively, we suggest WISP-2/CCN5 silencing may be a critical event during differentiation and progression of PAC and mutant p53 is possibly an important player in pursuing this episode.
 ...
PMID:Loss of WISP-2/CCN5 signaling in human pancreatic cancer: a potential mechanism for epithelial-mesenchymal-transition. 1738 17

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.
 ...
PMID:Pancreatic intraepithelial neoplasia in heterotopic pancreas: evidence for the progression model of pancreatic ductal adenocarcinoma. 1766 42

The understanding of the biology of pancreatic carcinoma has greatly benefited from studies of genetic alterations and molecular expression in experimental models as well as in pre-cancerous and cancerous tissues by mean of molecular amplification and large scale transcriptome analysis. P16, TP53, DPC4/Smad4 tumor suppressor pathways are genetically inactivated in the majority of pancreatic carcinomas, whereas oncogenic k-ras is activated. The activating mutation of the K-ras oncogene on codon 12 seems to occur early in pancreatic carcinogenesis and detecting its mutation in tumor samples could have a clinical relevance in term of positive (improvement of current histological diagnosis) and differential diagnosis (versus chronic pancreatitis) of pancreatic cancer. At a late stage of tumor development, an increase of telomerase activity, an over expression of growth factors and/or their receptors (EGF, nerve growth factor, gastrin, bombesin), of proangiogenic factors (VEGF, FGF, PDGF), of invasiveness factors (metalloproteinases, E-cadherin, beta integrin, urokinase and tissue plasminogen activator) occur. All these molecular events contribute to the progression and to the metastatic potential of this carcinoma. New markers and targets are currently studied among microRNA and epigenetics events such as methylation and acetylation. Among all these molecular markers, some are now tested for their potential clinical interest in term of diagnosis or therapeutic target.
 ...
PMID:[New molecular targets in pancreatic cancer]. 1854 14

We investigated the SPINK 1 mutations in 156 sporadic pancreatic cancer (PCa), and 8 pancreatic cancer with chronic pancreatitis (CPPCa) patients, and in 527 healthy subjects. The results demonstrated that 3 of 8 patients with CPPCa (37.5%) had the SPINK 1 gene N34S mutation. In addition, 3 of 156 sporadic PCa patients (1.9%) and 1 of them (0.6%) had the N34S and IVS3+2T>C mutation, respectively. The combined frequency of 2.5% was significantly higher than that of healthy subjects (0.38%), suggesting that the SPINK 1 mutation is an important risk factor for the development of pancreatic cancer. To investigate the genetic difference between sporadic PCa and CPPCa, we investigated several factors involved in the pathogenesis of PCa in 6 CPPCa and 15 sporadic PCa patients. The factors examined were genes including K-ras, p53, smad 4, p-smad 1, CXCL 14, NF-kB subunit p65 and Wnt 5a. No significant difference was found in the comparative examination of these factors, suggesting that the molecular disorders appeared to occur similarly in CPPCa as well as sporadic PCa. To assess the role of fibrosis in pancreatic carcinogenesis, we investigated the effects of pancreatic stellate cells (PSCs), which are largely responsible for pancreatic fibrogenesis, on duct cells, in vitro and in vivo. Activated PSCs were found surrounding precancerous duct cells in the tissues of a dimethylbenzanthracene mouse model and those of human PCa. Consistently, human pancreatic epithelial duct cells cultured with PSC conditioned media showed increased cell proliferation and colony formation, suggesting that PSCs may promote pancreatic ductal tumorigenesis.
 ...
PMID:Chronic pancreatitis and pancreatic cancer: prediction and mechanism. 1989 93

Pancreatic acinar cells acquire in vitro a pancreatic progenitor phenotype associated with activation of p53, growth arrest and senescence. A similar program is also activated in chronic pancreatitis. To assess the mechanisms involved in this process, we cultured pancreatic acinar cells from wild-type, p53(-/-), p16(-/-) and p21(-/-) mice. Cultures from p53(-/-) mice, but not those from p16(-/-) or p21(-/-) mice, display an enhanced proliferation and can be expanded continuously for more than 20 passages. p53(-/-) cells also display features of stemness such as enhanced sphere formation, increased expression of pancreatic multipotent progenitor markers (Ptf1a, Pdx1, Cpa1, c-myc, Sox9 and Hnf1b), and of the stemness regulators Bmi1 and Klf4. Upon subculture, p53(-/-) cells undergo an epithelial-mesenchymal transition (EMT) and express high levels of vimentin and of the transcriptional regulators Snai1, Snai2, Twist, Zeb1 and Zeb2. Genetic lineage tracing unequivocally demonstrates the epithelial origin of the cells with mesenchymal phenotype. These cells express the endodermal markers Hhex, Pdx1, Sox9, Hnf1b, Foxa2, Gata6 and Sox17, and the stem cell markers c-myc, Bmi1 and Klf4. Cultures from p53(+/-) mice display intermediate levels of the transcription factors involved in EMT but do not surpass the growth arrest. Our findings support the notion that p53 controls both growth and epithelial cell differentiation in the pancreas. These observations have important implications regarding the mechanisms through which p53 inactivation in tumors may be associated with aggressive biological behavior.
 ...
PMID:p53-dependent regulation of growth, epithelial-mesenchymal transition and stemness in normal pancreatic epithelial cells. 2183 95

The murine double minute-2 (MDM2) gene encodes a 90 kDa protein which binds and inactivates the protein product of the p53 tumor suppressor gene. To elucidate the potential role of MDM2 in benign and malignant hyperproliferative conditions in the pancreas, we studied MDM2 expression in cultured human pancreatic cancer cells and in pancreatic tissues from normal donors, patients with pancreatic ductal adenocarcinoma and patients with chronic pancreatitis (CP). All the tested cell lines (PANC-1, COLO-357, HPAF and T3M4) expressed a 5.5 kilobase MDM2 mRNA transcript and exhibited nuclear MDM2 immunostaining. MDM2 mRNA levels were comparable in all 18 normal and 14 CP tissues for which RNA samples were available for analysis. By comparison with the normal samples, MDM2 mRNA levels were increased 6.4-fold in 8 of 12 human pancreatic cancer samples (p < 0.0001). All 8 samples exhibited nuclear MDM2 immunostaining, which was also present in 24 of 37 additional pancreatic cancers. Mild MDM2 immunoreactivity was seen in only 1 of 20 CP samples and in none of the 18 normal samples. These findings indicate that MDM2 is overexpressed in a majority of pancreatic adenocarcinomas, but not in CP samples. This selective overexpression raises the possibility that MDM2 may contribute to pancreatic neoplastic transformation by interfering with the growth-suppressing activity of wild-type p53.
 ...
PMID:Increased mdm2 expression and immunoreactivity in human pancreatic ductal adenocarcinoma. 2155 10

In spite of continuous research efforts directed at early detection and treatment of pancreatic cancer, the outlook for patients affected by the disease remains dismal. With most cases still being diagnosed at advanced stages, no improvement in survival prognosis is achieved with current diagnostic imaging approaches. In the absence of a dominant precancerous condition, several risk factors have been identified including family history, chronic pancreatitis, smoking, diabetes mellitus, as well as certain genetic disorders such as hereditary pancreatitis, cystic fibrosis, familial atypical multiple mole melanoma, and Peutz-Jeghers and Lynch syndromes. Most pancreatic carcinomas, however, remain sporadic. Current progress in experimental molecular techniques has enabled detailed understanding of the molecular processes of pancreatic cancer development. According to the latest information, malignant pancreatic transformation involves multiple oncogenes and tumor-suppressor genes that are involved in a variety of signaling pathways. The most characteristic aberrations (somatic point mutations and allelic losses) affect oncogenes and tumor-suppressor genes within RAS, AKT and Wnt signaling, and have a key role in transcription and proliferation, as well as systems that regulate the cell cycle (SMAD/DPC, CDKN2A/p16) and apoptosis (TP53). Understanding of the underlying molecular mechanisms should promote development of new methodology for early diagnosis and facilitate improvement in current approaches for pancreatic cancer treatment.
 ...
PMID:Molecular biology of pancreatic cancer. 2173 1

Pancreatic cancer is the fourth leading cause of cancer death overall. The factors that favor the development of pancreatic cancer can be divided into hereditary and acquired. Cancerogenesis is best explained by a "multi-hit" hypothesis, charcterized with the developmental sequence of cellular mutatitions, forcing mutant cell to inappropriate proliferation and preventing its repair and programmed cell death (apoptosis). The most common mutations involve K-ras gene, epidermal growth factor (EGF-R) and HER2 gene. Continuous stimulation and secretion of vascular endothelial growth factor (VEGF) enhances the permeability of blood vessels provides nutrient supply to tumor site through newly formed vascular channels. This phenomena is known as vasculogenic mimicry. Loss of function of tumor-suppressor genes has been documented in pancreatic cancer, especially in CDKN2a, p53, DPC4 and BRCA2 genes. SDKN2A gene inactivation occurs in 95% of pancreatic adenocarcinoma. As regards acquired factors, smoking is only confirmed risk factor that increases the risk of pancreatic cancer. Diabetes, alcohol consumption, central obesity in men, infection with Helicobacter pylori and chronic pancreatitis are suspected, but not proven risk factors. Consumption of fruits and vegetables does not protect, while the consumption of meat processed at high temperatures increases the risk of pancreatic cancer. According to some studies, lykopene and folate levels are reduced in pancreatic carcinoma patients, reduced folate intake increases the risk of pancreatic carcinoma (48%), and this risk can be diminished by introducing folate-rich foods to diet, not by using pharmaceutical products. Occupational exposure to chlorinated hydrocarbons, vinyl chloride, nickel, chromium, insecticides and acrylic amide minimally increases the risk for pancreatic cancer. Exposure to cadmium (metal industry) associated with smoking result in the accumulation of cadmium in pancreatic tissue and the possible impact on carcinogenesis.
 ...
PMID:Etiology and oncogenesis of pancreatic carcinoma. 2321 74

Pancreatic exocrine cell plasticity can be observed during development, pancreatitis with subsequent regeneration, and also transformation. For example, acinar-ductal metaplasia (ADM) occurs during acute pancreatitis and might be viewed as a prelude to pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDAC) development. To elucidate regulatory processes that overlap ductal development, ADM, and the progression of normal cells to PanIN lesions, we undertook a systematic approach to identify the Prrx1 paired homeodomain Prrx1 transcriptional factor as a highly regulated gene in these processes. Prrx1 annotates a subset of pancreatic ductal epithelial cells in Prrx1creER(T2)-IRES-GFP mice. Furthermore, sorted Prrx1(+) cells have the capacity to self-renew and expand during chronic pancreatitis. The two isoforms, Prrx1a and Prrx1b, regulate migration and invasion, respectively, in pancreatic cancer cells. In addition, Prrx1b is enriched in circulating pancreatic cells (Pdx1cre;LSL-Kras(G12D/+);p53(fl/+);R26YFP). Intriguingly, the Prrx1b isoform, which is also induced in ADM, binds the Sox9 promoter and positively regulates Sox9 expression. This suggests a new hierarchical scheme whereby a Prrx1-Sox9 axis may influence the emergence of acinar-ductal metaplasia and regeneration. Furthermore, our data provide a possible explanation of why pancreatic cancer is skewed toward a ductal fate.
 ...
PMID:The Prrx1 homeodomain transcription factor plays a central role in pancreatic regeneration and carcinogenesis. 2335 95


<< Previous 1 2 3 4 5 6 Next >>