The expression of proto-oncogene c-jun in human pancreatic cancer

The proto-oncogene c-jun is involved in cellular proliferation by interferi ng with signals that lean to cellular differentiation. Moreover the inducti on of metalloproteinase gene appears to utilise the c-jun oncogene as intra cellular messenger. The aims of this study were to evaluate a) the expressi on of c-jun oncogene in pancreatic cancer b) its relation with tumor histol ogical features. Surgical specimens of pancreatic cancer were collected fro m 22 patients radically operated upon, and from 11 submitted to palliation. As a cona ol group, 5 specimens of normal pancreas and 5 specimens of chro nic pancreatitis were studied. C-jun staining was graded as follows: (-) po sitive cells < 10%, (+) from 10 to 30%, (+ +), from 30 to 60%, (+ + +) from 60 to 90%. Glucagon and somatostatin staining was graded counting the posi tive cells of total numer of Langherans islet cells counted. c-Jun expressi on (low: <30% and high: >30%) was related to stage, architectural and cytol ogical grading, vascular; lymph nodal, perineural invasion. Normal pancreas and chronic pancreatitis tissues appear to express the c-jun protein in le ss than 10% of ductal cells. The percentage of tumor cells stained for c-ju n is increased as compared to the control group in 28/33 cases: in 13 (46%) if ranges from 10 to 30%; in 10 (36%) from 30 to 60% and in 5 (18%) from 6 0 to 90%. The frequency of high or. low c-jun expression is not different i n relation to the histological features of tumor. Moreover; c-jun protein i s present in 40% of cells of Langherans islets in nor-mal pancreas, chronic pancreatitis and pancreatic cancer. The Langherans islet cells stained for c-jun exhibit also a positivity So,- glucagon. In conclusion; a) in pancre atic cancer; the expression of c-jun is increased in tumour cells in majori ty of cases as compared to the control group, b) a c-jun positivity is also found in alpha cells with a pattern not different from control group, but the relation between the alpha cells and c-jun production is unknown, c) c- jun expression does not vary in relation to histological findings.