Abstract
Pancreatic carcinoma (PC) is very serious oncologic disease with the very bad prognosis. Severe malnutrition and deregulation of fatty acids (FA) metabolism are connected with PC.
Abnormal metabolism of FA is also present in other oncologic diseases, in cardiovascular diseases, in obesity and in diabetes mellitus type 2. Dietary intake of FA over several weeks as well as endogenic metabolism (synthesis, lipoperoxidation) of FA both influence the composition of FA in plasma phospholipids and cholesteryl esters.
Several studies proved the association of risk for malignancies including PC with total fat and saturated FA intake. Risk for PC was lower in obese patients who consumed increased amount of polyunsaturated FA and decreased amount of saturated FA.
High intake of n-6 polyunsaturated FA, especially linoleic acid, increases the risk for development of gastrointestinal tumours such as colorectal carcinoma, PC and also breast and prostate carcinoma. Epidemiological studies proved beneficial effects of n-3 polyunsaturated FA in the risk and progession of tumours.
Generally, n-6 polyunsaturated FA acts as enhancing factor for proliferation and invasiveness of tumours, metastases formation and inflammatory reaction of the organism, whereas n-3 polyunsaturated FA opposes these effects. Increased de novo synthesis of FA due to overexpression of FA synthase (FAS) and stearoyl-CoA desaturase (SCD-1) is present in malignant tumours.
Physiologically, FAS is expressed only in the fat tissue and in the liver. Pathologically, FAS is expressed in tumour cells to satisfy nutritional requirements of these cells.