Search

To ascertain modifications in the activation products derived from oxygen free radicals in patients with chronic pancreatic and extra-pancreatic diseases, lipid peroxide activity was measured in the sera of 40 control subjects, 28 patients with pancreatic cancer, 49 with chronic pancreatitis, and 53 with extra-pancreatic diseases. In 142 of the subjects, elastase 1, amylase, and pancreatic isoamylase activities were also determined. Increased lipid peroxide activities were found in some patients with both chronic pancreatic and extra-pancreatic diseases. Patients with chronic pancreatitis studied during relapse had higher activities of lipid peroxides than those without active disease. No difference was found between the values in patients with pancreatic cancer with liver metastases and those without. Correlations were found between lipid peroxides and both amylase and pancreatic isoamylase activities; no correlation was detected between lipid peroxides and elastase 1. In benign biliary tract disease a correlation was detected between lipid peroxides and alanine aminotransferase and alkaline phosphatase activities. In all patients, however, a correlation was found between alkaline phosphatase and lipid peroxide activities. It is concluded that activation of oxygen derived free radicals occurs in chronic pancreatic as well as in extra-pancreatic disease; it seems to reflect the degree of inflammation.

A large number of enzymes of different classes (e.g., proteolytic, lipolytic, nucleolytic) are synthesized by the acinar cells of the exocrine pancreas and secreted into the pancreatic ducts [1]. Although the secretory pathway of the acinar cells leads to the discharge of enzymes through the secretory pole of the cell, small amounts may be released into the bloodstream, as occurs in endocrine secretion. Therefore small quantities of pancreatic enzymes may be detected in the circulation of healthy humans.

Suicide gene therapy with FCY1 gene, encoding cytosine deaminase (CD), together with FUR1, encoding uracil phosphoribosyltransferase (UPRT), has been proposed for pancreatic cancer therapy in vivo. We ascertained whether gene therapy with FCY1-FUR1 is effective in killing pancreatic cancer cells after 5-fluorocytosine (5-FC) treatment.AsPC1, BxPC3, Capan1, MIA PaCa2, and Panc1 cell lines were transfected using 2 plasmid vectors expressing CD only (pRSV-CD) or the chimera CD-UPRT (pRSV-CD-UPRT). Control and pRSV-CD- or pRSV-CD-UPRT-transfected cell lines were treated with 0, 0.1, 0.5, 1, 5, and 10 mM of 5-FC for 1, 3, 6, 8, 10, and 13 days.FCY1 alone did not confer sensitivity to 5-FC. The CD-UPRT-transfected BxPC3 and Panc1 were sensitive to very low 5-FC doses (0.1 mM). 5-Fluorocytosine-sensitive transfected cell lines rapidly converted 5-FC into 5-fluorouracil, whereas the 5-FC resistant cell lines had an impaired 5-FC conversion.Suicide gene therapy with the FCY1 gene alone was ineffective in the treatment of pancreatic cancer in vitro. The pRSV-CD-UPRT construct conferred 5-FC sensitivity to some pancreatic cancer cell lines. Therefore, the application in vivo of suicide gene therapy with FCY1 alone or in combination with the FUR1 gene is probably destined to fail.

Context Chronic inflammation is suggested to play a key role in cancer initiation and progression. Epithelial-mesenchymal transition (EMT) is an essential developmental program that becomes reactivated in adult tissues to promote the progression of cancer. EMT is characterized by an enhanced cell motility, the loss of the epithelial marker E-cadherin (CDH1), and the overexpression of the mesenchimal marker N-cadherin (CDH2). Master regulators of EMT are the transcription factors Snail, Slug, ZEB and Twist. Objective To ascertain whether the inflammatory molecules S100A8, S100A9 and TGF-b1, overexpressed in pancreatic cancer (PaCa), might start the EMT program. Methods BxPC3 cells were treated with 10 nM S100A8 or S100A9, 0.02 ng/mL TGF-b1 or with vehicle alone (reference) for 72 hours. The expression (mRNA) of Snail, Slug, ZEB1, ZEB2, Twist, CDH1 and CDH2 were quantified by RT-PCR (Light Cycler). N-cadherin protein expression was evaluated by immunohistochemistry (IHC). Results TGF-b1 significantly enhanced the expression of all the tested EMT markers (P=0.037 for CDH1, CDH2, Slug, ZEB1 and ZEB2; P=0.005 for Snail and Twist). S100A8 significantly enhanced the expression levels of Twist (median fold increase: 4, range: 2.6-22.3; P=0.007) while S100A9 did not (median: 2, range: 0.8-9.3, P=0.10). Both molecules reverted TGF-b1 effects on Twist expression (TGF-b1: median: 6, range: 3.6-42.6; TGF-b1 and S100A8: median: 3, range: 2.3-3.8; TGF-b1 and S100A9: median: 3.3, range: 3.1-4.2). By IHC, control cells showed an inhomogeneous non-continuous membranous N-cadherin immunostain. The treatments with both TGF-b1 and S100A8 resulted in an enforced moderate complete membranous immunostain. The combined treatment with TGF-b1 and S100A8 was less effective on protein visualization in comparison to any single treatments (weak to moderate complete immunostain). Conclusion TGF-b1 activate the transcriptional program which underlies the EMT in PaCa cells. A dual role for S100A8 in the EMT was shown: it promotes the EMT by inducing Twist mRNA and N-cadherin protein expression, but it antagonizes TGF-b1 effects on both targets. S100A9 exerts only inhibitory effects on TGF-b1., JOP. Journal of the Pancreas, Vol 13, N° 5S (2012): September (Suppl.) - p. 548-650