Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) as candidates for tumor markers in patients with pancreatic cancer.

BACKGROUND: Various alcohol dehydrogenase (ADH) isoenzymes and aldehyde dehydrogenase (ALDH) exist in the pancreas. Moreover, ADH and ALDH are present in pancreatic cancer cells. The activity of ADH class III isoenzymes is significantly higher in cancerous than in healthy tissues. The expression of these enzymes in cancer cells is reflected by increased enzyme activity in the sera and thus could be helpful for diagnosing pancreatic cancer. The aim of this study was to investigate the potential role of ADH and ALDH as tumor markers for pancreatic carcinoma. METHODS: Serum samples were taken from 165 patients with pancreatic cancer and 166 healthy controls. Total ADH activity and class III and IV isoenzymes were measured by photometric and ALDH activity, ADH I and II by the fluorometric method. RESULTS: There was a significant increase in the activity of ADH III isoenzyme (14.03 mU/l vs 11.45 mU/l; p < 0.001) and total ADH activity in the sera of pancreatic cancer patients compared to the control. The diagnostic sensitivity for ADH III was 70%, specificity 76%, positive and negative predictive values were 79% and 71% respectively. Area under ROC curve for ADH III was 0.64. CONCLUSION: The results suggest a potential role for ADH III as a marker of pancreatic cancer.

Alcohol dehydrogenase (ADH) isoenzymes and aldehyde dehydrogenase (ALDH) activity in the sera of patients with acute and chronic pancreatitis.

OBJECTIVE: Acute and chronic pancreatitis is a major complication of alcohol abuse. The pancreas can metabolize ethanol via oxidative pathway involving the enzymes - alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) as well as the nonoxidative pathway. Human pancreas tissue contains various ADH isoenzymes and possesses also ALDH activity. In this paper we have measured the activity of alcohol dehydrogenase isoenzymes, and aldehyde dehydrogenase in the sera of patients with acute and chronic pancreatitis. METHODS: Serum samples were taken for routine biochemical investigation from 46 patients suffering from acute pancreatitis and 32 patients with chronic pancreatitis. Total ADH activity was measured by photometric method with p-nitrosodimethylaniline (NDMA) as a substrate and ALDH activity by the fluorometric method with 6-methoxy-2-naphtaldehyde as a substrate. For the measurement of the activity of class I isoenzymes we employed the fluorometric methods, with class-specific fluorogenic substrates. The activity of class III alcohol dehydrogenase was measured by the photometric method with n-octanol and class IV with m-nitrobenzaldehyde as a substrate. RESULTS: A statistically significant increase of class III alcohol dehydrogenase isoenzymes was found in the sera of patients with acute and chronic pancreatitis. The median activity of this class isoenzyme in the patients group increased about 35% in the comparison to the control level. The total alcohol dehydrogenase activity was also significantly higher (23.5%) among patients with pancreatitis than healthy ones. The activities of other tested ADH isoenzymes and total ALDH were unchanged. The activity of the class I ADH isoenzyme was significantly higher in the sera of heavy drinkers with pancreatitis. CONCLUSION: We can state that the increase of the activity of class III alcohol dehydrogenase isoenzyme in the sera of pancreatitis patients seems to be caused by the release of this isoenzyme from damaged pancreatic cells.

[The role of ethanol in pathogenesis of pancreatitis]. / Rola alkoholu etylowego w patogenezie zapalen trzustki.

Alcohol consumption is associated with pancreatitis, but the mechanism inducing this injury is not fully understood. The pancreas can metabolize ethanol via oxidative pathway involving alcohol dehydrogenase (ADH), cytochrome P-450 2E1 and the nonoxidative pathway. Injury to the pancreas due to its capacity to metabolize ethanol may be mediated by direct effects of both fatty acid ethyl esters (FAEEs) and acetaldehyde and by alterations induced within the cells during ethanol metabolism, such as changes in the intracellular redox state and the generation of oxidative stress. These processes induce changes in pancreatic digestive enzymes secretion, what contributes to development of pancreatitis.