Enhanced expression of vascular endothelial growth factor in human pancreatic cancer correlates with local disease progression

Vascular endothelial growth factor (VEGF) is an angiogenic polypeptide that has been implicated in cancer growth. In the present study, we characterized VEGF expression in cultured human pancreatic cancer cell lines and determined whether the presence VEGF in human pancreatic cancers is associated with enhanced neovascularization or altered clinicopathological characteristics. VEGF mRNA transcripts were present in all six tested cell lines (ASPC-1, CAPAN-1, MIA-PaCa-2, PANC-1, COLO-357, and T3M4). Immunoblotting with a highly specific anti-VEGF antibody revealed the presence of VEGF protein in all of the cell lines. Northern blot analysis of total RNA revealed a 5.2-fold increase in VEGF mRNA transcript in the cancer samples in comparison with the normal pancreas. Immunohistochemical and in situ hybridization analysis confirmed the expression of VEGF in the cancer cells within the tumor mass. Immunohistochemical analysis of 75 pancreatic cancer tissues revealed the presence of strong VEGF immunoreactivity in the cancer cells in 64% of the cancer tissues. The presence of VEGF in these cells was associated with increased blood vessel number, larger tumor size, and enhanced local spread but not with decreased patient survival. These findings indicate that VEGF is commonly overexpressed in human pancreatic cancers and that this factor may contribute to the angiogenic process and tumor growth in this disorder.

Cloning of a gene highly overexpressed in cancer coding for a novel KH-domain containing protein

In a previous large scale screen for differentially expressed genes in pancreatic cancer, we identified a gene highly overexpressed in cancer encoding a novel protein with four K-homologous (KH) domains. KH-domains are found in a subset of RNA-binding proteins, including pre-mRNA-binding (hnRNP) K protein and the fragile X mental retardation gene product (FMR1). By fluorescence in situ hybridization (FISH) the identified gene named koc (KH domain containing protein overexpressed in cancer) was assigned to chromosome 7p11.5. Two pseudogenes were localised on chromosome 6 and 11. The cloned koc cDNA has a 250 bp 5'-UTR, a 1740 bp ORF and a 2168 bp 3'-UTR. The AU-rich 3'-untranslated region of koc contains eight AUUUA and four AUUUUUA reiterated motifs. The deduced koc protein with 580 amino-acids has a relative molecular mass (Mr) of approximately 65,000 (65 K). The koc transcript is highly overexpressed in pancreatic cancer cell lines and in pancreatic cancer tissue as compared to both, normal pancreas and chronic pancreatitis tissue. High levels of expression were as well found in tissue samples of other human tumours. As the KH domain has been shown to be involved in the regulation of RNA synthesis and metabolism, we speculate that koc may assume a role in the regulation of tumour cell proliferation by interfering with transcriptional and or posttranscriptional processes. However, the precise role of koc in human tumour cells is unknown and remains to be elucidated.

Identification of genes with specific expression in pancreatic cancer by cDNA representational difference analysis

cDNA representational difference analysis (cDNA-RDA) is a polymerase-chain-reaction-coupled subtractive and kinetic enrichment procedure for the isolation of differentially expressed genes. In this study, the technique was used to isolate novel genes specifically expressed in pancreatic cancer. cDNA-RDA was done on cDNA reverse transcribed from a poly(A)+ mRNA pool made from 10 cancer tissues (tester) by using as a driver a cDNA from a poly(A)+ mRNA pool made from a combination of 10 tissues of chronic pancreatitis and 10 healthy pancreatic tissues. The use of chronic pancreatitis in addition to healthy pancreas mRNA in the driver preparation eliminated the influence of stromal tissue components present as contamination in the cancer-specific preparations. Such cDNA-RDA led to the isolation of 16 distinct, cancer-specific gene fragments. These were confirmed to be overexpressed in pancreatic cancer tissues by Northern blot analysis. Sequence analysis revealed homologies to five genes previously implicated in the carcinogenesis of the pancreas or other tissues. Eleven fragments had no significant homology to any known gene and thus represent novel candidate disease genes. The experiments demonstrate that cDNA-RDA is a reproducible and highly efficient method for the identification of novel genes with cancer-specific expression.

Differential localization of transforming growth factor-beta isoforms in human gastric mucosa and overexpression in gastric carcinoma

Transforming growth factor beta (TGF-beta) isoforms comprise a family of multifunctional polypeptide growth factors that either inhibit or stimulate cell proliferation. We examined TGF-beta expression in normal human gastric mucosa and carcinoma. The distribution and expression of TGF-beta isoforms in 4 normal mucosa samples from organ donors, in 12 normal mucosa samples adjacent to gastric cancer and in 12 gastric carcinomas were examined using immunohistochemistry and Northern blot analysis. Because TGF-beta s regulate collagen expression, collagen type I alpha1 mRNA amounts were also examined. Immunohistochemical analysis of normal human gastric tissue samples indicated that TGF-beta1 localized principally in parietal cells but also in some surface mucus cells, TGF-beta2 was present exclusively in chief cells and TGF-beta3 was present in parietal, chief and mucus cells. In the gastric cancers, strong colocalization of TGF-beta1, -beta2 and -beta3 was evident in the cancer cells. Northern blot analysis indicated that, compared to normal gastric tissue, gastric cancers showed a 4.8- and 6-fold increase in mRNA amounts encoding TGF-beta1 and TGF-beta3, respectively. In contrast, TGF-beta2 mRNA amounts were comparable in both groups. Northern blot analysis showed a 10-fold increase in human collagen type I alpha1 mRNA amounts compared to normal gastric tissue. These findings imply a role forTGF-beta s in normal human gastric mucosa function, and raise the possibility that the aberrant colocalization and overexpression of all 3 TGF-beta isoforms in human gastric cancer cells in vivo may contribute to the pathobiology of gastric carcinoma.

Cytotoxic cells are activated in cellular infiltrates of alcoholic chronic pancreatitis

BACKGROUND & AIMS

Perforin messenger RNA (mRNA) expression has been shown to be a specific in vivo activation marker for cytotoxic cells. In this study, the contribution of cell-mediated cytotoxicity in the pathogenesis of alcoholic chronic pancreatitis is assessed.

METHODS

Tissue sections of patients with alcoholic chronic pancreatitis were analyzed for perforin mRNA expression by in situ hybridization. In a further step, the phenotype and the relative frequency of perforin mRNA-expressing cells were determined.

RESULTS

In the normal pancreas, perforin mRNA-expressing cells are rarely present (mean, 0.3 cells/mm2). In contrast, the frequency of perforin mRNA-expressing cells is increased severalfold in diseased tissue specimens (mean, 6.6 cells/mm2). The frequency of perforin mRNA-expressing cells is high in the CD56+ (18%) and CD8+ cell population (12%) but low in the CD4+ cell population (1%).

CONCLUSIONS

The significantly elevated frequencies of perforin mRNA-expressing cells in the pancreas of patients with alcoholic chronic pancreatitis suggest an involvement of cell-mediated cytotoxicity in the pathogenesis of this disease. The preferential localization of these activated cells close to areas with parenchyma provides circumstantial evidence that autoreactive cytotoxic cells may contribute to tissue destruction in alcoholic chronic pancreatitis.

Immune cell infiltration and growth-associated protein 43 expression correlate with pain in chronic pancreatitis

BACKGROUND & AIMS

Changes in innervation pattern and neuropeptide content have been shown in chronic pancreatitis (CP), including increased neuronal expression of growth-associated protein 43 (GAP-43). We used GAP-43 as an established marker of neuronal plasticity and correlated histological findings with pain scores of patients with CP.

METHODS

In tissue samples from 29 patients with CP, the parenchyma-fibrosis ratio, degree of perineural immune cell infiltration, and neuronal GAP-43 immunoreactivity were determined by digitized morphometry and correlated with individual pain scores.

RESULTS

In CP, GAP-43 was significantly increased in pancreatic nerve fibers and intrinsic neurons. GAP-43 expression correlated with individual pain scores. The infiltration of pancreatic nerves by immune cells was significantly correlated with the intensity of pain. Pain scores correlated neither with the degree of pancreatic fibrosis nor with the duration of the disease.

CONCLUSIONS

The results suggest that infiltration of pancreatic nerves by immune cells and neuronal plasticity are pathogenic factors for the generation of pain, whereas the degree of pancreatic fibrosis has no major impact on pain in CP.

Differential localization of transforming growth factor-beta isoforms in human gastric mucosa and overexpression in gastric carcinoma

Transforming growth factor beta (TGF-beta) isoforms comprise a family of multifunctional polypeptide growth factors that either inhibit or stimulate cell proliferation. We examined TGF-beta expression in normal human gastric mucosa and carcinoma. The distribution and expression of TGF-beta isoforms in 4 normal mucosa samples from organ donors, in 12 normal mucosa samples adjacent to gastric cancer and in 12 gastric carcinomas were examined using immunohistochemistry and Northern blot analysis. Because TGF-beta s regulate collagen expression, collagen type I alpha1 mRNA amounts were also examined. Immunohistochemical analysis of normal human gastric tissue samples indicated that TGF-beta1 localized principally in parietal cells but also in some surface mucus cells, TGF-beta2 was present exclusively in chief cells and TGF-beta3 was present in parietal, chief and mucus cells. In the gastric cancers, strong colocalization of TGF-beta1, -beta2 and -beta3 was evident in the cancer cells. Northern blot analysis indicated that, compared to normal gastric tissue, gastric cancers showed a 4.8- and 6-fold increase in mRNA amounts encoding TGF-beta1 and TGF-beta3, respectively. In contrast, TGF-beta2 mRNA amounts were comparable in both groups. Northern blot analysis showed a 10-fold increase in human collagen type I alpha1 mRNA amounts compared to normal gastric tissue. These findings imply a role forTGF-beta s in normal human gastric mucosa function, and raise the possibility that the aberrant colocalization and overexpression of all 3 TGF-beta isoforms in human gastric cancer cells in vivo may contribute to the pathobiology of gastric carcinoma.

[Duodenum preserving resection of the head of the pancreas: a standard procedure in chronic pancreatitis]

Duodenum-preserving resection of the head of the pancreas was developed 25 years ago by Beger. This procedure is indicated in patients suffering from chronic pain in combination with inflammation of the head of the pancreas, common bile duct obstruction, pancreatic duct obstruction and/or obstruction of the retropancreatic vessels. At the Inselspital in Berne, 74 patients underwent this operation between 1993 and 1996. The median length of the operation was 380 min, with the need for transfusion in a median of 0 units (0-6). There was no postoperative mortality. Total postoperative morbidity was 13%. One patient needed relaparotomy on day 17 for small bowel obstruction. Median length of hospital stay was 11 days. Postoperatively, two patients developed diabetes. Duodenum-preserving resection of the head of the pancreas represents an organ-preserving principle of surgery. This procedure treats the complications of chronic pancreatitis and provides long-term pain relief in more than 80% of patients.

Gastric emptying following pylorus-preserving Whipple and duodenum-preserving pancreatic head resection in patients with chronic pancreatitis

BACKGROUND

After pylorus-preserving Whipple (PPW), delayed gastric emptying (DGE) is reported in up to 50% of these patients. We analyzed gastric emptying and hormonal adaptation of cholecystokinin (CCK), pancreatic polypeptide (PP), and gastrin following two surgical procedures for chronic pancreatitis (CP): the PPW and the duodenum-preserving pancreatic head resection (DPPHR).

METHODS

Ten patients underwent DPPHR and 10 underwent PPW for CP. Preoperatively and 10 days and 6 months postoperatively, gastric emptying (paracetamol absorption test) and CCK, gastrin, and PP were measured using a test meal stimulation.

RESULTS

The area under the serum paracetamol time curve for 0 to 120 minutes (AUC) showed no preoperative difference. Ten days postoperatively, the AUC was significantly reduced (P <0.05) after PPW but not after DPPHR. Six months postoperatively, AUC was comparable with the preoperative findings in DPPHR and PPW. The integrated 180-minute PP release was significantly reduced 10 days and 6 months postoperatively in both groups. The integrated 180-minute CCK release was decreased 10 days after PPW, but failed to be significant (P = 0.053). Gastrin levels were postoperatively unchanged.

CONCLUSION

Following DPPHR we found no delay in gastric emptying. In contrast, DGE occurs early after PPW. Our data may help explain the slower recovery in PPW patients with regard to weight gain and relief from pain, which may be due to the functional alteration of gastric emptying and motility after this type of surgery.

Progress report. A randomized multicenter European study comparing adjuvant radiotherapy, 6-mo chemotherapy, and combination therapy vs no-adjuvant treatment in resectable pancreatic cancer (ESPAC-1)

CONCLUSION

The ESPAC-1 trial is the largest study of its kind in pancreatic cancer and should definitively address the question of the role of conventional methods of adjuvant treatment in pancreatic cancer.

BACKGROUND

At the joint International Association of Pancreatology and the European Pancreatic Club meeting in Mannheim, Germany (June 12-15, 1996) a satellite meeting of the European Study Group for Pancreatic Cancer (ESPAC) met to discuss the progress of the ESPAC-1 trial.

METHODS

A randomized multicenter study to address which, if any, of the following adjuvant treatments are of benefit in patients with resectable pancreatic cancer: radiotherapy (40 Gy with 5-FU as a sensitizing agent), 6 mo of chemotherapy (5-FU and folinic acid), or a combination of these treatments.

RESULTS

From February 1994 to June 1996 (the time of the Mannheim meeting) 221 patients so far have been recruited into the three treatment arms and one control arm.

Pathological changes in pancreatic ducts from patients with chronic pancreatitis

CONCLUSION

Chronic pancreatitis and restricted pancreatic outflow are accompanied by pathological changes in the ducts, including inflammation and alterations in the microvasculature. These changes and loss of epithelium provide a likely explanation for increased release of serum proteins, immunoglobulins, and lactoferrin into the juice, and the possibility of luminal contents entering the extracellular space and bloodstream.

BACKGROUND

Enlargement of pancreatic ducts is a well-known phenomenon accompanying chronic pancreatitis and conditions restricting outflow of pancreatic juice. However, the relationship between ductal pathology and concomitant changes in the pancreatic juice is incompletely understood.

METHODS

Segments of pancreatic ducts removed at surgery from patients with chronic pancreatitis and conditions restricting outflow were studied by light and electron microscopy to assess the pathological changes.

RESULTS

Pathological changes in ducts from patients with chronic pancreatitis include chronic inflammation in the wall, enlarged and numerous capillaries packed with erythrocytes and leukocytes close to the lumen, and loss of epithelium and sometimes basement membrane. Plasma cells provide a source for increased immunoglobulins. Ducts from patients with diseases restricting outflow show significant pathology.

Localization of cholecystokinin A and cholecystokinin B-gastrin receptors in the human stomach

BACKGROUND & AIMS

Gastrin and cholecystokinin (CCK) are gut-brain peptides, with multiple functions in the gastrointestinal tract mediated through CCK-B-gastrin and CCK-A receptors. The receptor localization is, however, not well established in humans. The aim of this study was to investigate the distribution and pharmacological characteristics of CCK-A and CCK-B receptors in the human upper gastrointestinal tract and compare them with those in the rat and dog.

METHODS

CCK receptors were localized by in vitro receptor autoradiography with 125I-[Leu15]gastrin-I and 125I-[D-Tyr-Gly, Nle(28,31)]-CCK 26-33 in stomach and gallbladder.

RESULTS

High concentrations of CCK-B-gastrin receptors were detected in the midglandular region of the human fundic mucosa. CCK-A receptors were found in the basal region of the antral and fundic mucosa. CCK-A receptors were also located in the muscularis propria of antrum, fundus, and gallbladder, whereas CCK-B-gastrin receptors were only detected in gastric fundic circular muscle. Two nonpeptide CCK receptor antagonists distinguish both receptor subtypes. Comparisons among humans, dogs, and rats suggest that localization and density of CCK receptor subtypes in the upper gastrointestinal tract are species-dependent.

CONCLUSIONS

Localization of CCK receptor subtypes in human upper gastrointestinal tract provides a biochemical and morphological basis for the separate regulatory roles of gastrin and CCK.

Adjuvant therapy of pancreatic cancer using monoclonal antibodies and immune response modifiers

Pancreatic cancer is a devastating disease with poor survival. At present, no effective adjuvant or palliative therapies are available. Unresponsiveness to chemotherapy, radiotherapy, and antihormonal treatment is one of the reasons that pancreatic cancer patients have an overall median survival time of 4-6 mo. This article summarizes clinical trials on immunotherapy of pancreatic cancer using the murine monoclonal antibodies (MAbs) 17-1A and BW 494. In addition, the use of MAb treatment in combination with immune response modifiers is discussed. In four clinical trials, MAb 17-1A was given by iv infusion to 100 patients with pancreatic cancer. In 30 of the these patents, antibody treatment was accompanied by gamma-interferon, also given intravenously. Complete response, partial response, and stable disease were reported in 1,5, and 23 patients, respectively. Passive immunotherapy using the MAb BW 494 was carried out in 148 pancreatic cancer patients in two phase I and two phase II trials. In 1 out of 75 patients a partial response and in 25 out of 74 patients stable disease were reported. However, in a controlled randomized trial enrolling 61 patients following Whipple resection, comparable survival times in patients with and without MAb BW 494 treatment led to the termination of further clinical trials with this antibody. New clinical studies using humanized MAbs in combination with immune response modifiers should be initiated to further evaluate immunotherapy as a treatment option in pancreatic cancer.

[Duodenum preserving resection of the head of the pancreas: a new standard operation in chronic pancreatitis]

Between 1972 and 1993, 298 patients with chronic pancreatitis underwent a duodenum-preserving pancreatic head resection (DPPHR). The early and late outcomes were prospectively analyzed. An operative mortality rate of 1%, a postoperative morbidity rate of 28.5% and a relaparotomy rate of 5.7% for the DPPHR were competitive with the rates for Whipple resection. After a median late follow-up of 6 years (range: 1 to 22 years), late mortality was 9%; 88% of the patients had no or infrequent episodes of pain and 63% were completely rehabilitated professionally. Only 6 patients developed diabetes mellitus early postoperatively. Our study proves that the duodenum-preserving pancreatic head resection provides better results than the Whipple resection. Therefore, this operation should be adopted as a new standard operation in patients with chronic pancreatitis.

Duodenum-preserving pancreatic head resection: Long-term results

Early and late results from 298 patients with chronic pancreatitis who were surgically treated by means of duodenum-preserving pancreatic head resection (DPPHR) were prospectively analyzed. The aim of this operative procedure is to treat complications of chronic pancreatitis caused by inflammatory enlargement of the pancreatic head by decompressing the common bile duct, the pancreatic duct, the duodenum, and the retropancreatic intestinal vessels. End points of the study were early and late postoperative outcome. The follow-up period ranged from 1 to 22 years with a median follow-up of 6 years. In-hospital mortality was 1%, postoperative morbidity was 28.5%, and the rate of repeat laparotomy was 5.7%. Diabetes mellitus developed early in the postoperative period in six patients (2%). After a median follow-up of 6 years, late mortality was 8.9%. In the late follow-up period 88% of our patients were completely free of pain or had infrequent episodes and 63% were able to return to work. DPPHR might be considered as an alternative surgical technique in the treatment of chronic pancreatitis if the dominant lesion is in the pancreatic head.

Increased expression of transforming growth factor beta s after acute oedematous pancreatitis in rats suggests a role in pancreatic repair

BACKGROUND

Transforming growth factor beta isoforms (TGF beta s) belong to a family of multifunctional regulators of cellular growth and differentiation. They are mitogenic and chemotactic for fibroblasts and are potent stimulators of extracellular matrix production (collagen) and deposition. Upregulation of TGF beta transcription has been reported for several in vivo systems during repair after injury.

AIMS

To study the expression of the three mammalian isoforms of TGF beta (TGF beta 1-3) and their relation to collagen expression as a marker for fibroblast response in acute oedematous pancreatitis in rats.

METHODS

Using northern blot analysis and immunohistochemistry, the expression and localisation of TGF beta isoforms, collagen, and amylase were analysed during the course of acute oedematous pancreatitis in rats, experimentally induced by intravenous caerulein infusion.

RESULTS

Induction of acute pancreatitis resulted in a biphasic peak pattern of expression of TGF beta 1, beta 2, and beta 3 mRNA, with a pronounced increase from day 1 to day 3 (sixfold, 2.5-fold, fivefold, respectively) and again from day 5 to day 7 (three-fold, 2.3-fold, 3.5-fold, respectively). The temporal changes in TGF beta mRNA identically paralleled the expression in collagen mRNA. In contrast, amylase mRNA expression, used as a general indicator of acinar cell integrity, was slightly decreased after induction of acute pancreatitis. Immunohistochemical analysis of pancreatitis tissue showed that increased expression of TGF beta s was mainly present in the pancreatic acinar and ductal cells; this was evident within one day after pancreatitis induction.

CONCLUSION

Overexpression of TGF beta s after induction of acute pancreatitis suggests a role for these proteins in pancreatic repair and remodelling. The increased levels of TGF beta s may help suppress immune activation, and may contribute to the increase in the extracellular matrix including collagen and to the repair of the pancreatic parenchyma.

First clinical experience with fundus rotation gastroplasty as a substitute for the oesophagus

BACKGROUND

Leakage of oesophagogastric anastomosis has been associated with poor perfusion of the gastric tube. The authors recently developed a new form of gastroplasty, preserving not only the arterial arcade along the greater curvature, but also the lesser curvature. In this study their first clinical experience with that gastric tube is reported.

METHODS

Thirty-five patients undergoing either oesophagectomy or laryngopharyngo-oesophagectomy for malignant lesions and substitution of the oesophagus with a funds rotation gastroplasty were included. Patient outcome, including anastomotic leak, hospital mortality and morbidity rates, were studied prospectively.

RESULTS

Hospital mortality rate was one of 35 and anastomotic leak (one minor, one moderate) was found in two patients with no subsequent mortality. Further major morbidity included pulmonary dysfunction in the form of acute respiratory distress syndrome (ARDS) in seven patients. Mean (s.e.m.) hospital stay was 27(19) days, and 21(9) days in patients who did not develop ARDS.

CONCLUSION

Fundus rotation is a new method of gastroplasty that allows safe anastomosis of the tube with the remaining oesophagus or pharynx and is associated with a low leak rate even at high cervical levels.

Enhanced expression of urokinase plasminogen activator and its receptor in pancreatic carcinoma

Urokinase plasminogen activator (uPA) is a serine proteinase that has been suggested to play an important role in cancer invasion and metastasis. It binds to a specific membrane receptor denominated uPA receptor (uPAR). uPA activates plasminogen to form plasmin, which participates in tissue degradation and proteolysis. Binding of uPA to its receptor accelerates UPA's own activation from pro-uPA, enhancing the activity of the uPA/uPAR cascade. Using immunohistochemistry and Northern blot analysis, we analysed the role of uPA and uPAR in 30 human pancreatic cancers. Immunohistochemical analysis demonstrated moderate to strong immunostaining of both factors in most pancreatic cancers. Cancer lesions with signs of invasion exhibited the strongest immunohistochemical signals for both factors. In addition, in desmoplastic areas adjacent to the cancer cells, moderate uPA and uPAR immunoreactivity was detectable. Northern blot analysis revealed a sixfold and a fourfold increase in uPA and uPAR mRNA levels in pancreatic cancer, respectively, in comparison with normal controls (P<0.01). Correlation of the Northern blot data with the clinical parameters of the patients indicated that patients with concomitant overexpression of uPA and uPAR had a shorter post-operative survival (median 9 months; mean+/-s.d. 10.2+/-3.6 months) than patients in whom only one or none of these factors were overexpressed (median 18 months; mean+/-s.d. 20.3+/-8.7 months) (P<0.002). Our data suggest that uPA and uPAR may serve as prognostic markers in human pancreatic cancer and that the marked overexpression of both factors may create an environment that enables pancreatic cancer cells to invade surrounding tissues.

KAI1 expression is up-regulated in early pancreatic cancer and decreased in the presence of metastases

KAI1 is a metastasis suppressor gene for prostate cancer that is located on chromosome 11p11.2-13. Using Northern blot analysis and in situ hybridization, we studied expression of KAI1 mRNA in specimens from 14 normal pancreases and 27 primary pancreatic cancers, and then correlated the findings with the clinical and histopathological parameters of the patients. Northern blot analysis showed increased steady-state levels of KAI1 mRNA expression in 24 of 27 (89%) pancreatic cancer samples. In situ hybridization showed enhanced KAI1 mRNA levels in the pancreatic cancer cells in 82% cancer tissues. The stroma surrounding the cancer mass and normal pancreatic tissue adjacent to the cancer cells exhibited very low levels of KAI1 mRNA expression. Correlation of the mRNA levels obtained by Northern blot analysis with clinical parameters of the patients revealed that KAI1 mRNA levels were significantly higher (P < 0.01) in earlier tumor stages (I, II), compared with advanced tumor stages (III, IV) in which lymph node or distant metastases were present. Furthermore, poorly differentiated tumors had significantly higher KAI1 mRNA levels than those that were moderately or well differentiated (P < 0.05). No association between KAI1 expression and survival was found. Our results indicate that KAI1 mRNA expression is reduced in patients with advanced tumor stages. This suggests that reduction of KAI1 expression might enable pancreatic cancer cells to spread in lymph nodes and to distant organs.

A pancreatic cancer-specific expression profile

We present an approach making use of technology established in the context of the genome project to describe a pancreatic cancer-specific expression profile and to identify new potential disease genes or disease-associated-genes. By use of gridded arrays of pancreatic cancer cDNA libraries and differential hybridizations we show that 4% the gridded cDNA library clones contain sequences preferentially expressed in pancreatic cancer. EST-sequencing of 369 distinct (408 total), differentially expressed sequences identified novel genes (32.5%) or homologs to EST-sequences with unknown function (26.3%). Homologies to known genes allow to determine a pancreatic cancer-specific expression profile, which provides for the first time evidence for complex primary and secondary alterations of gene expression responsible for the development of the phenotype of pancreatic cancer cells. In addition this has led to the identification of novel differentially expressed genes, which represent potential oncogenes or disease-associated markers and may be helpful for the development of therapeutic or diagnostic modalities.

The risk of pancreaticointestinal anastomosis can be predicted preoperatively

The risk of developing postoperative complications following pancreatic resection depends mainly on how difficult it is to perform a proper pancreaticointestinal anastomosis. We have evaluated the serum pancreolauryl test, a rapid tubeless pancreatic function test, as a simple preoperative predictor of the degree of pancreatic fibrosis. Degree of fibrosis in turn provides an indirect parameter for the difficulties of performing a proper and safe pancreaticointestinal anastomosis. In 35 patients (21 chronic pancreatitis, 14 pancreatic tumors) undergoing major pancreatic resection, we found a negative correlation (r = -0.75, p < 0.001) between the degree of fibrosis at the resection margin and the serum pancreolauryl test results. Patients with chronic pancreatitis had a significantly higher degree of fibrosis at the resection margin (59 +/- 22 vs. 34 +/- 25%; X +/- SD; p < 0.01) and lower fluorescein serum concentrations (2.6 +/- 1.9 vs. 4.3 +/- 2.1 micrograms/ml; X +/- SD; p < 0.01) in comparison with patients with pancreatic tumors. These findings indicate that the degree of pancreatic fibrosis, the difficulties of performing a proper pancreaticointestinal anastomosis, and subsequently the potential risk of postoperative complications can easily be predicted preoperatively.

Altered expression of transforming growth factor-beta S in chronic renal rejection

We examined the altered expression of transforming growth factor-beta s in chronic renal rejection in humans, including transforming growth factor beta-1 (TGF-beta 1), TGF-beta 2, TGF-beta 3 and their receptors, transforming growth factor beta receptor type I (T beta R-I) and T beta R-II. Using Northern blot analysis and immunohistochemistry, 10 specimens of chronically rejected and 8 normal kidney samples were analyzed. By Northern blot analysis the expression of mRNA encoding TGF-beta 1, TGF-beta 2, TGF-beta 3 (P < 0.02), T beta R-I and T beta R-II (P < 0.02) was decreased in chronically rejected renal cortex samples, compared to normal controls. Immunohistochemical analysis of the normal renal cortex showed strong immunostaining for TGF-beta 1 and TGF-beta 3, and mild immunostaining for TGF-beta 2 in the proximal and distal tubulointerstitium, but no signal for any of the TGF-beta isoforms in the glomeruli or in the cortical vessels. In sharp contrast, the glomeruli and the cortical vessels of the rejected kidney specimens exhibited strong immunostaining for TGF-beta 1 and TGF-beta 3, whereas the tubules revealed a decrease in immunoreactivity. T beta RI and T beta RII immunostaining showed similar changes as observed with TGF-beta 1 and TGF-beta 3 antibodies. There was a concomitant increase in B-cell accumulation in the glomeruli, while T-cells and macrophages were diffusely abundant in the rejected samples. Since TGF-beta S are potent inducers of extracellular matrix proteins and have been shown to be involved in fibrotic disease, the increase in TGF-beta 1 and TGF-beta 3 immunoreactivity in the glomeruli suggests that there is a redistribution in TGF-beta expression in chronic renal allograft rejection. Together with changes affected by B-cell mediated immunity, the above alterations might contribute to the histopathological changes that occur in this disorder, such as intimal fibrosis, arteriosclerosis and glomerular and tubular sclerosis.