preproenkephalin and Pancreatitis--Chronic

CpG islands of the promoter region of some genes are methylated in pancreatic cancer tissue and the detection of this methylation has been suggested to be useful in the diagnosis of various cancers. The aim of this study was to investigate whether the detection of methylated CpG islands in plasma can be used in the diagnosis of pancreatic cancer.. Plasma DNA was collected from patients with pancreatic cancer, chronic pancreatitis, and healthy controls. The methylation status of six genes, UCHL1, NPTX2, SARP2, ppENK, p16, and RASSF1A, was checked by methylation-specific PCR and was subsequently confirmed by direct sequencing after bisulfite treatment.. CpG island methylation was detectable in 13 of 16 patients (81.3%) with pancreatic cancer, 1 of 29 healthy controls (3.5%), and 8 of 13 patients with chronic pancreatitis (61.5%). The mean number of genes with CpG island methylation was 1.6±1.2 in pancreatic cancer, 0.04±0.19 in healthy controls, and 1.2±1.1 in chronic pancreatitis. Among six genes, p16 was more specifically methylated in pancreatic cancer compared with chronic pancreatitis (p=0.016). The methylation status was not correlated with smoking history, tumor size, or cancer stage.. The detection of methylated genes in the plasma may have a role in differentiating between pancreatic cancers and healthy controls but not between pancreatic cancer and chronic pancreatitis.

Topics: Adult; Aged; Biomarkers, Tumor; C-Reactive Protein; Carcinoma, Pancreatic Ductal; Carrier Proteins; Cell Line, Tumor; CpG Islands; DNA Methylation; Enkephalins; Female; Genes, p16; Humans; Intercellular Signaling Peptides and Proteins; Male; Membrane Proteins; Middle Aged; Nerve Tissue Proteins; Pancreatic Neoplasms; Pancreatitis, Chronic; Polymerase Chain Reaction; Protein Precursors; Tumor Suppressor Proteins; Ubiquitin Thiolesterase

A chronic pancreatitis model was developed in young male Lewis rats fed a high-fat and alcohol liquid diet beginning at three weeks. The model was used to assess time course and efficacy of a replication defective herpes simplex virus type 1 vector construct delivering human cDNA encoding preproenkephalin (HSV-ENK).. Most surprising was the relative lack of inflammation and tissue disruption after HSV-ENK treatment compared to the histopathology consistent with pancreatitis (inflammatory cell infiltration, edema, acinar cell hypertrophy, fibrosis) present as a result of the high-fat and alcohol diet in controls. The HSV-ENK vector delivered to the pancreatic surface at week 3 reversed pancreatitis-associated hotplate hypersensitive responses for 4-6 weeks, while control virus encoding beta-galactosidase cDNA (HSV-beta-gal) had no effect. Increased Fos expression seen bilaterally in pain processing regions in control animals with pancreatitis was absent in HSV-ENK-treated animals. Increased met-enkephalin staining was evident in pancreas and lower thoracic spinal cord laminae I-II in the HSV-ENK-treated rats.. Thus, clear evidence is provided that site specific HSV-mediated transgene delivery of human cDNA encoding preproenkephalin ameliorates pancreatic inflammation and significantly reduces hypersensitive hotplate responses for an extended time consistent with HSV mediated overexpression, without tolerance or evidence of other opiate related side effects.

Topics: Animals; Behavior, Animal; DNA, Complementary; Enkephalins; Genetic Vectors; Herpesvirus 1, Human; Inflammation; Male; Models, Animal; Pancreatitis, Chronic; Protein Precursors; Rats; Rats, Inbred Lew; Receptors, Opioid, mu; Spinal Cord; Time Factors

Aberrant methylation of CpG islands is a common mechanism for the dysregulation of tumor suppressor genes in a variety of human malignancies. Preproenkephalin ppENK) hypermethylation is recognized in 90% of pancreatic carcinoma (PCa) tissues, but not in normal pancreas. We analyzed ppENK hypermethylation in pure pancreatic juice (PPJ) in patients with PCa, intraductal papillary mucinous neoplasms (IPMN), and chronic pancreatitis (CP), and elucidated its usefulness as a marker in the diagnosis of PCa compared with p53 mutation.. PPJ was collected endoscopically from 28 patients with PCa, 15 patients with IPMN, and 20 patients with CP. DNA was extracted from the supernatant and the sediment of PPJ. Methylation-specific polymerase chain reaction was performed for hypermethylation analysis of ppENK. In addition, single-strand conformation polymorphism and direct sequencing were performed simultaneously to identify p53 mutations.. The incidence of ppENK hypermethylation in the supernatant and/or the sediment of PPJ was 50% (14 of 28) in patients with PCa. In contrast, the incidence of ppENK hypermethylation was 26.7% (4 of 15) in patients with IPMN, and 5% (1 of 20) in patients with CP (P < 0.002). The incidence of p53 mutations in the PPJ was 42.9% (12 of 28) in patients with PCa and 0% (0 of 20) in patients with CP. Furthermore, the incidence of ppENK hypermethylation and/or p53 mutations in the PPJ was enhanced to 67.9% (19 of 28) in patients with PCa in the combination assay.. These results suggest that ppENK hypermethylation in PPJ is specific for cancer, and the combination assay with p53 enhances the genetic diagnosis of PCa.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoma, Pancreatic Ductal; DNA Methylation; DNA Mutational Analysis; Enkephalins; Female; Genes, p53; Humans; Male; Middle Aged; Mutation; Pancreatic Juice; Pancreatic Neoplasms; Pancreatitis, Chronic; Polymerase Chain Reaction; Polymorphism, Single-Stranded Conformational; Protein Precursors