Portal but not peripheral serum levels of interleukin 6 could interfere with glucose metabolism in patients with pancreatic cancer

Interleukin 6 (IL-6), an autocrine growth factor for many tumors, seems to favour tumor spread to the liver. Our aims were first to evaluate the patte rn of portal and systemic IL-6 levels in patients with pancreatic cancer (P C, n = 18) and chronic pancreatitis (CP, n = 22) compared with controls (CS , n = 20); and second, to ascertain whether there was any relation between IL-6 levels and tumor spread or PC-associated Diabetes mellitus. For all su bjects, a fasting serum sample was obtained from a cubital vein; a portal s erum sample was obtained from nine PC and three CP patients. In cubital and portal sera we measured IL-6, interleukin 1 beta (IL-lb), CA 19-9, c-react ive protein (CRP) and amylase. Systemic IL-6 levels were significantly high er in PC patients than in CS. In PC, portal IL-6 levels were significantly higher than the corresponding systemic values. The same pattern was found i n the three CP patients, whereas IL-lb, CA 19-9, CRP and amylase portal lev els were the same as systemic values. No correlation was found between PC s tage and systemic or portal IL-6 levels. Portal IL-6 levels were correlated with the corresponding fasting serum glucose values. A significant correla tion was found between IL-6 values and CRP ALT, total bilirubin, GGT and cr eatinine, but not amylase. In conclusion: (1) Portal IL-6, which is partly of pancreatic origin, is first metabolised in the liver; (2) Systemic IL-6 reflects hepatic and renal functions rather than local conditions in the pa ncreas; (3) IL-6 does not appear to influence PC spread; (4) IL-6, which is released in large amounts by the inflamed pancreas, may contribute to dete rmining diabetes, thus interfering with the signal transducing pathways inv olved in glucose metabolism in liver cells. (C) 1998 Elsevier Science BN. A ll rights reserved.