Enhanced erbB-3 expression in human pancreatic cancer correlates with tumor progression

The erbB-3 gene encodes a transmembrane protein that is related to the epidermal growth factor (EGF) receptor and erbB-2. We compared erbB-3 expression in the normal human pancreas, human pancreatic carcinomas, and cultured human pancreatic cancer cell lines. Northern blot analysis of total RNA revealed the anticipated 6.2-kb mRNA transcript in all 19 normal pancreatic samples. In 17 of 27 pancreatic cancers, there was a 6.7-fold increase (P < 0.001) in erbB-3 mRNA levels. Southern blot analysis did not reveal erbB-3 gene amplification. Four of six pancreatic cancer cell lines exhibited the 6.2-kb erbB-3 mRNA transcript, and all four cell lines coexpressed the epidermal growth factor receptor and erbB-2. Using a highly specific antibody, we determined that faint to moderate erbB-3 immunoreactivity was present in the ductal cells in the normal pancreas. In 47% (27/58) of the pancreatic cancers, there were many cancer cells with intense erbB-3 immunostaining. The presence of erbB-3 in the cancer cells was associated with advanced tumor stage and shorter survival postoperatively. These data indicate that a significant proportion of human pancreatic cancers overexpress erbB-3, and that erbB-3 may contribute to disease progression in this disorder.

Increased expression of keratinocyte growth factor in human pancreatic cancer

Keratinocyte growth factor (KGF) is a member of the fibroblast growth factor (FGF) group of heparin-binding polypeptides. In the present study we sought to determine whether KGF is expressed in human pancreatic cancers. Using reverse transcriptase polymerase chain reaction (RT-PCR), a cDNA fragment of KGF was cloned and used to analyze Northern blots of RNA isolated from normal and cancerous human pancreatic tissues. Seven of 16 (44%) pancreatic cancer samples revealed significant overexpression of the 2.4 kilobase KGF mRNA transcript by comparison with the normal pancreas. Northern blot analysis failed to reveal the KGF transcript in several cultured human pancreatic cancer cell lines. However, by PCR analysis, some of the cell lines expressed KGF mRNA. Furthermore, 5 of 7 tested cell lines expressed the KGF receptor, and the growth of one cell line was enhanced by human recombinant KGF. These results suggest that KGF may participate in aberrant paracrine and autocrine pathways in human pancreatic cancer.

Differential distribution of human epidermal growth factor receptor family in acute pancreatitis

Using northern blot analysis and immunohistochemistry, we assessed the expression and distribution of human epidermal growth factor receptor-1 (HER-1), HER-2, and HER-3 in pancreatic tissues obtained from patients with acute pancreatitis (AP). Overall, HER-1, HER-2, and HER-3 mRNA levels were similar in the normal pancreas and in the pancreas of AP patients. However, three patients exhibited a significant increase in HER-1 mRNA levels. Furthermore, the distribution of the receptors differed with respect to the various cell types in the human pancreas. In the normal pancreas, moderate HER-1 and strong HER-3 immunoreactivity was present predominantly in the cytoplasm of acinar cells and to a lesser extent in the ductal cells, whereas strong HER-2 immunoreactivity was present in the islet cells. In the AP tissues, there was a marked increase in HER-1 immunoreactivity in acinar and ductal-like cells, whereas HER-3 immunoreactivity was less prominent in acini and increased in ductal-like cells. HER-2 immunoreactivity was again mainly evident in islet cells, but was also present in the ductal-like cells. These findings indicate that there is altered distribution of HERs in the pancreas following AP and raise the possibility that HERs may be involved in the process of pancreatic regeneration during recovery from AP.

Induction of platelet-derived growth factor A and B chains and over-expression of their receptors in human pancreatic cancer

Expression of platelet-derived growth factor (PDGF) and PDGF receptors was examined in cultured human pancreatic cancer cells, in the normal human pancreas and in pancreatic adenocarcinomas. mRNA transcripts encoding PDGF A and B chains, and PDGF receptor beta (PDGFR beta) were present in PANC-I and HPAF human pancreatic cancer cells. Transforming growth factor beta I (TGF-beta I), but not PDGF-AA or -BB, enhanced PDGF A and B chain mRNA levels in both cell lines. In the normal human pancreas PDGF A chain mRNA levels were relatively abundant, whereas PDGF B chain mRNA levels were not detected and PDGF receptor alpha (PDGFR alpha) and beta mRNA transcripts were present at low levels. PDGF immunoreactivity was present in islet cells, and PDGFR alpha was present in acinar cells, whereas PDGFR beta was present in acinar cells and in the connective tissue. In the pancreatic cancers, PDGF A chain mRNA transcripts were also abundant, and 6 of 13 samples exhibited the PDGF B chain mRNA transcript. In addition, there was a 7-fold increase in the levels of PDGFR alpha and PDGFR beta in the cancer samples by comparison with the normal pancreas. By immunohistochemistry, PDGF and both PDGF receptors were present in the cancer cells, and PDGFR beta was abundant in fibroblasts and endothelial cells within the connective tissue.

Randomized controlled multicentre study of the prevention of complications by octreotide in patients undergoing surgery for chronic pancreatitis

A randomized double-blind placebo-controlled multicentre trial was carried out in 247 patients undergoing major elective surgery for chronic pancreatitis to clarify whether the perioperative application of octreotide prevents postoperative complications. Eleven complications were defined, including death, anastomotic leakage, pancreatic fistula, abscess, fluid collection, shock, sepsis, bleeding, pulmonary insufficiency, renal insufficiency and postoperative pancreatitis. A total of 124 patients underwent pancreatic head resection, 55 left resection, 61 pancreaticojejunostomy and seven had other procedures. The overall mortality rate was 1.2 per cent (octreotide group 1.6 per cent, placebo group 0.8 per cent [corrected] (P not significant)). The postoperative complication rate in the octreotide group was 16.4 per cent (20 of 122 patients) and in the placebo group 29.6 per cent (37 of 125) (P < 0.007). The perioperative application of octreotide substantially reduces the risk of postoperative complications in patients undergoing major pancreatic surgery for chronic pancreatitis.

Expression and in-situ localization of genes coding for extracellular matrix proteins and extracellular matrix degrading proteases in pancreatic cancer

Pancreatic cancer shows a strong desmoplastic reaction characterized by a remarkable proliferation of interstitial connective tissue (collagens type I and III, fibronectin). In this study we have analyzed the balance of expression of mRNAs encoding extracellular matrix components (collagens I, III and IV, laminin, fibronectin), extracellular matrix-degrading metalloproteinases (MMP-1, -2, -3 and -9) and tissue inhibitors of metalloproteinases (TIMP-1 and -2) in pancreatic cancer and control pancreatic tissue by Northern-blot analysis and mRNA in situ hybridization. Transcripts for MMP-1 (interstitial collagenase) and MMP-3 (stromelysin-1) were not detectable in pancreatic cancer and control tissues. Steady-state levels of transcripts encoding extracellular matrix proteins, MMP-2 (72-kDa collagenase IV), MMP-9 (92-kDa collagenase type IV), TIMP-1 and TIMP-2 were elevated in the majority of pancreatic-cancer tissue samples as compared to control pancreatic tissue. A good correlation was seen between overexpression of these MMPs and TIMPs and the steady-state levels of transcripts coding for extracellular matrix proteins, the amount of collagen protein and the severity of the desmoplastic reaction. In situ hybridization studies localized transcripts coding for collagens type I and III to spindle-shaped stromal cells, whereas transcripts for MMP-2, MMP-9, TIMP-1 and TIMP-2 were found in both stromal and tumor cells. However, MMP-2 transcripts appeared to be more abundant in stromal cells, TIMP-1 and TIMP-2 transcripts were evenly distributed over tumor and stromal cells and relatively more MMP-9 transcripts were found in tumor cells. We conclude that, in human pancreatic cancer, MMP-2, MMP-9, TIMP-1 and TIMP-2 may be involved in processes leading to the strong desmoplastic reaction observed in these tumors. Both stromal and tumor cells appear to be the source of MMPs and TIMPs in human pancreatic cancer.

2-(fluorine-18)-fluoro-2-deoxy-D-glucose PET in detection of pancreatic cancer: value of quantitative image interpretation

PURPOSE

To evaluate use of positron emission tomography (PET) versus computed tomography (CT) in detection of pancreatic cancer and determine the value of quantitative and visual image interpretation of these techniques.

MATERIALS AND METHODS

Within 8 weeks before surgery, 73 patients with suspected pancreatic cancer or chronic pancreatitis underwent imaging with CT and with static PET after injection of 250-350 MBq of 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (FDG). Focal FDG uptake, considered a sign of malignancy, was calculated with standardized uptake values (SUVs) 60 minutes after injection.

RESULTS

With FDG PET, pancreatic carcinoma was correctly diagnosed in 41 (95%) of 43 patients, and chronic pancreatitis in 27 (90%) of 30 patients. With an SUV cutoff value of 1.53, both sensitivity and specificity for detection of malignancy were 93%. With CT, pancreatic cancer was correctly diagnosed in 33 (80%) of 41 patients, whereas results in seven (26%) of 27 patients with chronic pancreatitis were false-positive (specificity, 74%).

CONCLUSION

FDG PET enabled reliable differentiation of pancreatic adenocarcinoma from chronic pancreatitis. The sensitivity and specificity of visual image interpretation with FDG PET was statistically significantly higher (P < .05) than with CT.

Diagnosis of pancreatic cancer by 2[18F]-fluoro-2-deoxy-D-glucose positron emission tomography

The detection of pancreatic cancer or the discrimination between pancreatic cancer and chronic pancreatitis remains an important diagnostic problem. The increased glucose metabolism in malignant tumours formed the basis for this investigation, which focused on the role of positron emission tomography (PET) with 2[18F]-fluoro-2-deoxy-D-glucose (FDG) in the detection of pancreatic cancer and its differentiation from chronic pancreatitis. Eighty patients admitted for elective pancreatic surgery received preoperatively 250-350 mBq FDG intravenously and emission scans were recorded 45 minutes later. Intense focal activity in the pancreatic region was taken at the time of scanning as showing the presence of pancreatic cancer. The presence of cancer was later confirmed by histological examination of the surgical specimens and histological findings were compared with the preoperative PET results. Forty one patients with pancreatic cancer (group I: n = 42) had a focally increased FDG uptake in the pancreatic region. Two patients with a periampullary carcinoma (group II: n = 6) failed to develop FDG accumulation. In 28 patients with chronic pancreatitis (group III: n = 32) no FDG accumulation occurred. Overall sensitivity and specificity of PET for malignancy (group I + II) were 94% (45 of 48) and 88% (28 of 32), respectively. The standard uptake value of the patients with pancreatic carcinoma was significantly higher than in patients with chronic pancreatitis (3.09 (2.18) v 0.87 (0.56); p < 0.001; median (interquartile range)). These findings show that FDG-PET represents a new and non-invasive diagnostic procedure for the diagnosis of pancreatic cancer and to differentiate pancreatic cancer from chronic pancreatitis. However, the diagnostic potential of this technique requires further evaluation.

Changes of protein gene product 9.5 (PGP 9.5) immunoreactive nerves in inflamed appendix

The existence of chronic appendicitis is controversial. In this prospective study, we investigated possible changes in the innervation of the appendix under different pathological conditions and correlated histological findings with clinical observation. Thirty appendectomy specimens and 14 appendices obtained from organ donors or patients who underwent right hemicolectomy were immediately fixed in Bouin's solution and processed for immunocytochemistry using an antiserum directed against the panneuronal marker protein gene product 9.5 (PGP 9.5). The density of PGP 9.5 immunostaining was evaluated by digitized morphometry. Significant differences in the density of the PGP 9.5-immunoreactive area were detected in the mucosal layer. In the nonacute appendicitis group, PGP 9.5 was increased (10.99 +/- 3.15%) as compared to acute appendicitis (3.89 +/- 1.77%) and controls (4.98 +/- 1.25%). The significant increase of PGP 9.5 in nonacute appendicitis may suggest axonal sprouting leading to hyperinnervation of the mucosa. This may be a neuronal factor in the pathophysiology of the disease and pain symptoms.

Randomized trial of duodenum-preserving pancreatic head resection versus pylorus-preserving Whipple in chronic pancreatitis

BACKGROUND

In about 30% of patients, chronic pancreatitis leads to an inflammatory enlargement of the pancreatic head with subsequent obstruction of the pancreatic duct, common bile duct, and duodenum.

METHODS

In a prospective, randomized controlled trial, we compared duodenum-preserving pancreatic head resection (DPPHR) with pylorus-preserving Whipple (PPW) operation to define the advantages of each operation with regard to (1) postoperative complications, (2) glucose tolerance and induction of diabetes mellitus, and (3) postoperative pain and quality of life up to 6 months after operation for chronic pancreatitis.

RESULTS

The two study groups of 20 patients were both well balanced with regard to sex, age, history of chronic pancreatitis, and indication for surgery. Postoperative mortality was zero. After duodenum-preserving and pylorus-preserving resection, morbidity was 15% and 20%, respectively. After 6 months, patients who underwent the duodenum-preserving resection had less pain, greater weight gain, a better glucose tolerance, and a higher insulin secretion capacity.

CONCLUSION

The DPPHR compares favorably with the standard PPW operation and should be considered as an alternative procedure in the treatment of chronic pancreatitis.

Cellular and subcellular localization of transforming growth factor-alpha and epidermal growth factor receptor in normal and diseased human and hamster pancreas

Four normal pancreas, 8 chronic pancreatitis specimens, and 30 non-endocrine pancreatic tumors from humans and 6 normal and 6 induced pancreatic cancers in hamsters were examined immunohistochemically by antibodies against human transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGFR). Two normal pancreas and two pancreatic cancer specimens from each species were also studied immunoelectron microscopically by the immunogold method. In chronic pancreatitis, the reactivity and intensity of the staining with both antibodies were much greater in ductal/ductular cells than in the normal pancreas. All 30 pancreatic cancers reacted with both antibodies with a variable degree of reactivity and staining intensity. No correlation was found between the histological type of tumors, the degree of tumor differentiation, and the incidence and patterns of reactivity of either antibody. Immunoelectron microscopically, both EGFR and TGF-alpha were demonstrated primarily on the basal membrane. In the normal hamster pancreas, TGF-alpha was overexpressed in the alpha-cells but not in any other islet cells. Both TGF-alpha and EGFR were marginally detectable in the exocrine pancreas and in induced pancreatic lesions. This is the first demonstration of subcellular localization of TGF-alpha and EGFR in the normal and diseased human and hamster pancreas.

Coexpression of the c-met proto-oncogene and hepatocyte growth factor in human pancreatic cancer

The c-met proto-oncogene encodes a transmembrane tyrosine kinase receptor (MET) that has the capacity to modulate cell proliferation and differentiation; it is activated by the hepatocyte growth factor. Using a highly specific anti-MET antibody we found mild MET immunoreactivity in acinar, ductal, and islet cells in the normal human pancreas and intense MET immunoreactivity in many of the duct-like cancer cells in 14 of 16 human pancreatic adenocarcinomas. Intense MET immunoreactivity was also evident in the ductal cells in regions adjacent to the cancer cells. Northern blot analysis of total RNA revealed that, by comparison with the normal pancreas, pancreatic cancers exhibited a 7-fold (P < 0.01) increase in c-met mRNA levels. Hepatocyte growth factor mRNA levels were increased 10-fold (P < 0.05) in the same cancers. The concomitant over-expression of c-met and hepatocyte growth factor in human pancreatic cancers suggests that there is excessive activation of c-met-dependent signaling pathways that may contribute to pancreatic cancer cell growth in vivo.

p53 expression in human pancreatic cancer correlates with enhanced biological aggressiveness

Immunohistochemical analysis of the p53 tumor suppressor gene was performed in 69 human pancreatic ductal adenocarcinomas, using a highly specific anti-p53 antibody. Nuclear immunoreactivity was found in 40 tumors, yielding an overall frequency of 58%. Immunoblotting confirmed that nuclear immunoreactivity was associated with increased p53 protein levels. p53 mRNA levels were increased in 9 of 9 tested cancers, without evidence for gene amplification. Analysis of the immunostaining data by chi-square and log-rank indicated that the presence of nuclear immunoreactivity correlated with a more advanced clinical stage, and a statistically significant decrease in the post-operative survival period. In 12 cancers, metastatic tissue samples were also available for p53 analysis. Nuclear p53 immunostaining in the primary tumors was not always associated with p53 immunoreactivity in the metastatic samples, and metastases occurred in the absence of nuclear p53 immunoreactivity in the primary lesion. These findings suggest that increased p53 protein levels in human pancreatic cancer may be due not only to p53 mutations which attenuate the degradation of the protein but also to an increase in p53 mRNA levels leading to increased p53 synthesis, and that p53 nuclear immunoreactivity in these cancers implies enhanced tumor aggressiveness but is not essential for the development of metastases.

Chronic pancreatitis is associated with increased concentrations of epidermal growth factor receptor, transforming growth factor alpha, and phospholipase C gamma

The epidermal growth factor (EGF) receptor is a transmembrane protein that binds EGF and transforming growth factor alpha (TGF alpha), and that stimulates phospholipase C gamma 1 (PLC gamma 1) activity. In this study the role of the EGF receptor in chronic pancreatitis was studied. By immunohistochemistry, the EGF receptor, TGF alpha, and PLC gamma 1 were found to be expressed at high concentrations in pancreatic ductal and acinar cells from chronic pancreatitis patients. Northern blot analysis showed that, by comparison with normal controls, 19 of 27 chronic pancreatitis tissues exhibited a 5.7-fold increase in EGF receptor mRNA concentrations, and 20 of 27 chronic pancreatitis tissues exhibited a sixfold increase in TGF alpha mRNA concentrations. In situ hybridisation confirmed that overexpression occurred in ductal and acinar cells, and showed that both mRNA moieties colocalised with their respective proteins. These findings suggest that TGF alpha may act through autocrine and paracrine mechanisms to excessively activate the overexpressed EGF receptor in the two major cell types of the exocrine pancreas, thereby contributing to the pathobiology of this disorder.

Penetration of ciprofloxacin into the human pancreas

The aim of this study was to determine the concentrations of ciprofloxacin in human pancreatic tissue and juice. Concentrations were measured by high-pressure liquid chromatography (HPLC). Two hundred mg of ciprofloxacin were administered as a short i.v. infusion (30 min). The median ciprofloxacin concentrations 140 min (median) after the start of infusion in pancreatic tissue as well as in pancreatic juice were 0.9 mg/kg (mg/l). The penetration ratio was 1.0 for pancreatic tissue and 0.83 for pancreatic juice. With regard to the minimal inhibitory concentrations (MIC) for the respective bacteria, ciprofloxacin seems to be an appropriate drug for the treatment of septic complications in necrotizing pancreatitis. Future clinical trials are necessary to prove this assumption.

Induction and expression of heparin-binding EGF-like growth factor in human pancreatic cancer

Heparin-binding EGF-like growth factor (HB-EGF) is a polypeptide with an apparent molecular weight of 22 kilodalton that is related to epidermal growth factor (EGF) and that binds and activates the EGF receptor. We examined HB-EGF biological action and expression in human pancreatic cancer cell lines, and compared HB-EGF expression in normal and cancerous pancreatic tissues. HB-EGF enhanced the growth of human pancreatic cancer cells in a dose-dependent manner. Several cell lines expressed HB-EGF mRNA transcripts, and the transcript level was enhanced by HB-EGF, as well as by 12-O-tetradecanoylphorbol-13-acetate and transforming growth factor-alpha (TGF-alpha). By comparison with the normal pancreas, HB-EGF mRNA levels were increased in human pancreatic cancer tissues. These findings suggest that HB-EGF may participate in aberrant autocrine and paracrine activation of the EGF receptor, thereby contributing to pancreatic cancer cell growth.

Induction and expression of amphiregulin in human pancreatic cancer

The epidermal growth factor receptor is activated by a family of polypeptides that includes the growth factor amphiregullin (AR). Using Northern blot analysis and the polymerase chain reaction, we now report that AR mRNA is expressed in human pancreatic cancer cell lines, and that this expression is enhanced in several of these cell lines by tetradecanoyl phorbol acetate and transforming growth factor alpha. AR was also expressed in normal and malignant pancreatic tissues. However, in the normal pancreas, AR immunostaining was most evident in the nuclei of ductal cells. In contrast, in many carcinomas, AR was also present in the cytoplasm of the ductal-like cancer cells. Cytoplasmic localization of AR was associated with a more advanced clinical stage. These findings suggest that AR may contribute to aberrant activation of the epidermal growth factor receptor in human pancreatic cancer, and may enhance disease progression.

A subgroup of patients with chronic pancreatitis overexpress the c-erb B-2 protooncogene

OBJECTIVE

Chronic pancreatitis (CP) is a chronic condition associated with pancreatic fibrosis. A small subgroup of patients with CP develop enlargement of the head of the pancreas (EHP). This study examined some of the mechanisms that may lead to the development of EHP.

SUMMARY BACKGROUND

The c-erb B-2 protooncogene encodes a 185-kDa transmembrane growth factor receptor (p185) that regulates cell growth and differentiation.

METHODS

The authors analyzed c-erb B-2 expression in samples obtained from the head of the pancreas from 26 patients with CP (5 women, 21 men) using immunohistochemical and molecular technique. A diagnosis of CP with EHP was made when the vertical pancreatic head diameter was greater than 4 cm (14 patients), as determined by contrast-enhanced computed axial tomography scan. Pancreatic tissues from 15 healthy organ donors served as control subjects.

RESULTS

In all patients without EHP and in the healthy control subjects, p185 immunoreactivity was present at low levels. In contrast, strong p185 immunoreactivity was observed in acinar and ductal cells in all patients with EHP. By in situ hybridization, c-erb B-2 messenger ribonucleic acid (mRNA) grains were expressed at high levels in patients with CP with EHP in both ductal and acinar cells. Northern blot analysis demonstrated a 4.5-fold increase (p < 0.001) in c-erb B-2 mRNA levels in patients with EHP compared with patients without EHP and healthy control subjects. Southern blot analysis did not reveal c-erb B-2 gene amplification or rearrangement.

CONCLUSIONS

These findings indicate the c-erb B-2 is not overexpressed in most patients with CP. However, its overexpression in patients with CP with EHP suggest that c-erb B-2 may contribute to the pathophysiologic processes that lead to pancreatic head enlargement.

[Molecular biology of pancreatic cancer: overexpression of fibroblast growth factors]

In the present study, the expression of a acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor-1 were analyzed in 60 pancreatic cancer samples using Northern blot analysis, immunoblotting, in situ hybridization and immunohistochemical techniques. aFGF, bFGF and FGFR-1 were present in 63%, 55% and 52% of the tumor samples, respectively. Twenty-seven of the 60 pancreatic cancer tissue samples exhibited coexpression of aFGF and bFGF. In contrast, 14 of the tumor samples did not show immunoreactivity for aFGF or bFGF in the tumor cells. The expression of aFGF in the tumor cells had no influence on the postoperative survival period, whereas patients whose tumors were positive for bFGF and/or FGF-receptor-1 had significantly shorter postoperative survival periods. Our results suggest that bFGF and FGFR-1 may play a role in the growth behavior of pancreatic cancer and may contribute to tumor aggressiveness.

Carcinoid of the ampulla of Vater. Clinical characteristics and morphologic features

BACKGROUND

Carcinoid tumors of the gastrointestinal tract are most common localized in the appendix, followed by the small intestine, the rectum, and the stomach. The localization of these tumors at the ampulla of Vater is extremely seldom.

METHODS

In the present study the authors describe two patients with carcinoid tumors of the ampulla Vater and review 71 previously published cases.

RESULTS

Most patients presented with jaundice, but without carcinoid syndrome. Because the tumor grows submucosally, preoperative diagnosis was correct only in 15%. Most tumors were around 2 cm in size. Metastasis to lymph nodes and/or liver was present in 45%. Standard treatment is Whipple resection or local excision in small tumors.

CONCLUSIONS

Carcinoid tumors of the ampulla of Vater are an extremely rare clinical entity. Generally, the prognosis is good with a 5-year survival period of 90%.