Gemcitabine combined with the monoclonal antibody nimotuzumab is an active first-line regimen in KRAS wildtype patients with locally advanced or metastatic pancreatic cancer: a multicenter, randomized phase IIb study.

BACKGROUND: This randomized study was designed to investigate the superiority of gemcitabine (gem) plus nimotuzumab (nimo), an anti-epidermal growth factor receptor monoclonal antibody, compared with gem plus placebo as first-line therapy in patients with advanced pancreatic cancer. PATIENTS AND METHODS: Patients with previously untreated, unresectable, locally advanced or metastatic pancreatic cancer were randomly assigned to receive gem: 1000 mg/m2, 30-min i.v. once weekly (d1, 8, 15; q29) and nimo: fixed dose of 400 mg once weekly as a 30-min infusion, or gem plus placebo, until progression or unacceptable toxicity. The primary end point was overall survival (OS), secondary end points included time to progression, overall response rate, safety and quality of life. RESULTS: A total of 192 patients were randomized, with 186 of them being assessable for efficacy and safety (average age 63.6 years). One-year OS/progression-free survival (PFS) was 34%/22% for gem plus nimo compared with 19%/10% for gem plus placebo (HR = 0.69; P = 0.03/HR = 0.68; P = 0.02). Median OS/PFS was 8.6/5.1 months for gem plus nimo versus 6.0/3.4 mo in the gem plus placebo group (HR = 0.69; P = 0.0341/HR = 0.68; P = 0.0163), with very few grade 3/4 toxicities. KRAS wildtype patients experienced a significantly better OS than those with KRAS mutations (11.6 versus 5.6 months, P = 0.03). CONCLUSION: This randomized study showed that nimo in combination with gem is safe and well tolerated. The 1-year OS and PFS rates for the entire population were significantly improved. Especially, those patients with KRAS wildtype seem to benefit. The study was registered as protocol ID OSAG101-PCS07, NCT00561990 and EudraCT 2007-000338-38.

Phase II randomised proof-of-concept study of the urokinase inhibitor upamostat (WX-671) in combination with gemcitabine compared with gemcitabine alone in patients with non-resectable, locally advanced pancreatic cancer.

BACKGROUND: To evaluate the efficacy and tolerability of the urokinase plasminogen activator (uPA) inhibitor upamostat in combination with gemcitabine in locally advanced pancreatic adenocarcinoma (LAPC). METHODS: Within a prospective multicenter study, LAPC patients were randomly assigned to receive 1000 mg m(-2) of gemcitabine IV weekly either alone (arm A) or in combination with 200 mg (arm B) or 400 mg (arm C) oral upamostat daily. Efficacy endpoints of this proof-of-concept study included response rate, time to first metastasis, progression-free and overall survival (OS). RESULTS: Of the 95 enroled patients, 85 were evaluable for response and 93 for safety. Median OS was 12.5 months (95% CI 8.2-18.2) in arm C, 9.7 months (95% CI 8.4-17.1) in arm B and 9.9 months (95% CI 7.4-12.1) in arm A; corresponding 1-year survival rates were 50.6%, 40.7% and 33.9%, respectively. More patients achieved a partial remission (confirmed responses by RECIST) with upamostat combination therapy (arm C: 12.9%; arm B: 7.1%; arm A: 3.8%). Overall, only 12 patients progressed by developing detectable distant metastasis (arm A: 4, arm B: 6, arm C: 2). The most common adverse events considered to be related to upamostat were asthenia, fever and nausea. CONCLUSION: In this proof-of-concept study targeting the uPA system in LAPC, the addition of upamostat to gemcitabine was tolerated well; similar survival results were observed for the three treatment arms.

Members of the EpCAM signalling pathway are expressed in gastric cancer tissue and are correlated with patient prognosis.

BACKGROUND: We investigated the expression of members of the epithelial cell adhesion molecule (EpCAM) signalling pathway in gastric cancer (GC) testing the following hypotheses: are these molecules expressed in GC and are they putatively involved in GC biology. METHODS: The study cohort consisted of 482 patients. The following members of the EpCAM signalling pathway were analysed by immunohistochemistry and were correlated with various clinico-pathological patient characteristics: extracellular domain of EpCAM (EpEX), intracellular domain of EpCAM (EpICD), E-cadherin, ß-catenin, presenilin-2 (PSEN2), and ADAM17. RESULTS: All members of the EpCAM signalling pathway were differentially expressed in GC. The expression correlated significantly with tumour type (EpEX, EpICD, E-cadherin, ß-catenin, and PSEN2), mucin phenotype (EpEX, EpICD, ß-catenin, and ADAM17), T-category (EpEX, E-cadherin, and ß-catenin), N-category (EpEX and ß-catenin), UICC tumour stage (EpEX, EpICD, ß-catenin, and PSEN2), tumour grade (EpEX, EpICD, E-cadherin, ß-catenin, and PSEN2), and patients' survival (EpEX, EpICD, and PSEN2). A significant coincidental expression in GC was found for EpEX, EpICD, E-cadherin, ß-catenin, PSEN2, and ADAM17. Decreased immunodetection of EpEX in locally advanced GC was not associated with decreased EpCAM mRNA levels. CONCLUSION: All members of the EpCAM signalling pathway are expressed in GC. The expression correlated significantly with each other and with various clinico-pathological patient characteristics, including patients' survival. Thus, the EpCAM signalling pathway is a highly interesting putative therapeutic target in GC.

Her2/neu testing in gastric cancer: evaluating the risk of sampling errors.

BACKGROUND: We evaluated the risk of sampling errors in specimens of biopsy size, which may be caused by heterogeneous overexpression of Her2/neu in gastric cancer (GC). PATIENTS AND METHODS: The study cohort comprised 454 gastrectomy patients with adenocarcinoma of the stomach or esophago-gastric junction. Tissue micro-arrays (TMAs) served as 'biopsy procedure' and were generated from formalin-fixed and paraffin-embedded tissue: five tissue cylinders were collected randomly from each tumor, rendering 2230 core cylinders. These were compared with 454 whole tissue sections obtained from the same paraffin blocks. Her2/neu expression and gene amplification were analyzed by immunohistochemistry and in situ hybridization. The Her2/neu status was determined according to GC scoring system by two independent observers. RESULTS: In whole tissue sections, 37 (8.1%; observer 1) and 38 (8.4%; observer 2) of the GCs, and in the corresponding TMAs, 28 (6.3%; observer 1) and 28 (6.3%; observer 2) of the GCs were classified as Her2/neu-positive (kappa value 98.5% and 96.2%; P < 0001). Comparison of whole tissue sections with corresponding TMAs showed a false-negative rate of 24% and a false-positive rate of 3% for TMAs. CONCLUSION: Assessment of the Her2/neu status in tissue biopsies carries a significant risk of sampling errors, thereby rendering patients unsuitable for treatment with trastuzumab.

Multicenter phase II trial to investigate safety and efficacy of gemcitabine combined with cetuximab as adjuvant therapy in pancreatic cancer (ATIP).

BACKGROUND: To investigate whether addition of cetuximab to standard adjuvant chemotherapy with gemcitabine improves outcome in pancreatic cancer, specifically whether the rate of disease-free survival (DFS) at 18 months (primary end point) exceeds the previously reported 35% of gemcitabine alone. PATIENTS AND METHODS: Prospective, open-label, multicenter, nonrandomized phase II study in 76 patients with R0- or R1-resected ductal adenocarcinoma of the pancreas included between October 2006 and November 2008. Gemcitabine and cetuximab were administered for 24 weeks. Secondary end points included overall survival (OS) and toxic effect. RESULTS: Seventy-three patients received cetuximab. Median DFS was 10.0 [95% confidence interval (CI) 8.9-13.6] months and the DFS rate at month 18 of 27.1% (16.7%-37.6%) was inferior to 35%. Median OS was 22.4 (18.2-27.9) months. Subgroup analyses revealed a nonsignificant increase in DFS for patients with versus without skin toxic effect ≥ grade 2 (median 14.7 versus 8.3 months, P = 0.073) and wild-type versus mutated K-Ras (median 11.5 versus 9.3 months, P = 0.57). Grade 3/4 toxic effects included neutropenia (11.0%), thrombopenia (7%), skin toxic effect (7%) and allergic reactions (7%). CONCLUSION: Addition of cetuximab to adjuvant gemcitabine does not seem to improve DFS or OS of unstratified pancreatic cancer patients. Trends for improved DFS in patients with wild-type K-Ras and skin toxic effect remain to be confirmed.

Treatment of hepatocellular carcinoma with sorafenib - focus on special populations and adverse event management.

Sorafenib, a receptor tyrosine kinase-inhibitor with anti-proliferative and anti-angiogenic activity, is currently the only approved systemic treatment for patients with hepatocellular carcinoma. It inhibits downstream signaling of VEGFR-2, PDGFR, c-Kit receptors and BRAF. Over the last four years comprehensive experience with sorafenib in this indication has been accumulated. In this review we discuss the current data on the use of sorafenib in patients with advanced HCC including special patient populations such as patients with impaired liver function, patients after transplantation, and others. The most frequent side-effects and practical tips on how to manage them are discussed in detail. In addition, we summarize the current experimental data on the use of sorafenib in combination treatment, e. g., together with transarterial chemoembolisation or other targeted agents.

Artificial intelligence for detection of microsatellite instability in colorectal cancer-a multicentric analysis of a pre-screening tool for clinical application.

BACKGROUND: Microsatellite instability (MSI)/mismatch repair deficiency (dMMR) is a key genetic feature which should be tested in every patient with colorectal cancer (CRC) according to medical guidelines. Artificial intelligence (AI) methods can detect MSI/dMMR directly in routine pathology slides, but the test performance has not been systematically investigated with predefined test thresholds. METHOD: We trained and validated AI-based MSI/dMMR detectors and evaluated predefined performance metrics using nine patient cohorts of 8343 patients across different countries and ethnicities. RESULTS: Classifiers achieved clinical-grade performance, yielding an area under the receiver operating curve (AUROC) of up to 0.96 without using any manual annotations. Subsequently, we show that the AI system can be applied as a rule-out test: by using cohort-specific thresholds, on average 52.73% of tumors in each surgical cohort [total number of MSI/dMMR = 1020, microsatellite stable (MSS)/ proficient mismatch repair (pMMR) = 7323 patients] could be identified as MSS/pMMR with a fixed sensitivity at 95%. In an additional cohort of N = 1530 (MSI/dMMR = 211, MSS/pMMR = 1319) endoscopy biopsy samples, the system achieved an AUROC of 0.89, and the cohort-specific threshold ruled out 44.12% of tumors with a fixed sensitivity at 95%. As a more robust alternative to cohort-specific thresholds, we showed that with a fixed threshold of 0.25 for all the cohorts, we can rule-out 25.51% in surgical specimens and 6.10% in biopsies. INTERPRETATION: When applied in a clinical setting, this means that the AI system can rule out MSI/dMMR in a quarter (with global thresholds) or half of all CRC patients (with local fine-tuning), thereby reducing cost and turnaround time for molecular profiling.

Effects of yoga in inflammatory bowel diseases and on frequent IBD-associated extraintestinal symptoms like fatigue and depression.

Quality of life (QoL) of persons with inflammatory bowel diseases (IBD) is often impaired by symptoms that do not primarily relate to intestinal inflammation. Among the most challenging extraintestinal symptoms are depression and fatigue, which are also frequent in other chronic diseases like multiple sclerosis, rheumatoid arthritis and cancer. Yoga as an ancient Indian tradition containing postures, breathing exercises and meditation may positively influence those symptoms. This review evaluates the current literature with regard to the effect of yoga-based interventions in persons with IBD and with regard to QoL, depression and fatigue in other somatic disorders. A systematic literature search yielded three trials examining the effects of yoga in patients with IBD and 37 trials addressing depressive syndromes or fatigue in somatic disorders. In summary, both in-person and video-based yoga classes are feasible, acceptable and safe as complementary treatment in patients with IBD and significantly improve anxiety and impaired quality of life. Current literature does not provide information on the effect of yoga on depression and fatigue in patients with IBD, but research from other somatic disorders or patients with depressive disorders implies the potential of yoga in this regard for persons with IBD. This should be specifically addressed in interventional trials with standardized yoga modules including patients with IBD suffering from fatigue, depression and/or impaired QoL.

A randomized multicenter phase II study comparing capecitabine with irinotecan or cisplatin in metastatic adenocarcinoma of the stomach or esophagogastric junction.

BACKGROUND: The combination of irinotecan with 5-fluorouracil demonstrates efficacy with tolerable safety in the first-line treatment of metastatic gastroesophageal cancer (mGC). This randomized phase II trial compared for the first time capecitabine with irinotecan or cisplatin in this setting. PATIENTS AND METHODS: Patients were randomly assigned to receive 3-week cycles of capecitabine 1000 mg/m(2), twice daily for 14 days, with on day 1 either irinotecan 250 mg/m(2) (XI) or cisplatin 80 mg/m(2) (XP). The primary end point was overall response rate (ORR) and secondary end points included progression-free survival (PFS), overall survival (OS) and safety. RESULTS: Of 118 patients recruited, 112 were eligible for safety analysis and 103 for efficacy analysis. In the XI and XP treatment arms, there were no marked differences in ORR, 37.7% versus 42.0%, and median PFS, 4.2 versus 4.8 months, although median OS was longer, 10.2 versus 7.9 months, respectively. Grade 3/4 toxicity was higher in the XP regimen for thrombocytes (18.2% versus 1.8%), nausea (23.6% versus12.3%) and vomiting (16.4% versus 1.8%) and in the XI arm for diarrhea (22.8% versus 7.3%). CONCLUSION: The comparable activity and safety of the XI and XP regimens establish XI as a relevant platinum-free first-line treatment choice for patients with mGC.

MicroRNA-143 targets DNA methyltransferases 3A in colorectal cancer.

BACKGROUND: MicroRNAs (miRNAs) are 19-25-nucleotides regulatory non-protein-coding RNA molecules that regulate the expressions of a wide variety of genes, including some involved in cancer development. In this study, we investigated the possible role of miR-143 in colorectal cancer (CRC). METHODS: Expression levels of human mature miRNAs were examined using real-time PCR-based expression arrays on paired colorectal carcinomas and adjacent non-cancerous colonic tissues. The downregulation of miR-143 was further evaluated in colon cancer cell lines and in paired CRC and adjacent non-cancerous colonic tissues by qRT-PCR. Potential targets of miR-143 were defined. The functional effect of miR-143 and its targets was investigated in human colon cancer cell lines to confirm miRNA-target association. RESULTS: Both real-time PCR-based expression arrays and qRT-PCR showed that miR-143 was frequently downregulated in 87.5% (35 of 40) of colorectal carcinoma tissues compared with their adjacent non-cancerous colonic tissues. Using in silico predictions, DNA methyltranferase 3A (DNMT3A) was defined as a potential target of miR-143. Restoration of the miR-143 expression in colon cell lines decreased tumour cell growth and soft-agar colony formation, and downregulated the DNMT3A expression in both mRNA and protein levels. DNMT3A was shown to be a direct target of miR-143 by luciferase reporter assay. Furthermore, the miR-143 expression was observed to be inversely correlated with DNMT3A mRNA and protein expression in CRC tissues. CONCLUSION: Our findings suggest that miR-143 regulates DNMT3A in CRC. These findings elucidated a tumour-suppressive role of miR-143 in the epigenetic aberration of CRC, providing a potential development of miRNA-based targeted approaches for CRC therapy.

Identification of retinoic acid-regulated nuclear matrix-associated protein as a novel regulator of gastric cancer.

BACKGROUND: Retinoic acid-regulated nuclear matrix-associated protein (RAMP) is a WD40 repeat-containing protein that is involved in various biological functions, but little is known about its role in human cancer. This study aims to delineate the oncogenic role of RAMP in gastric carcinogenesis. METHODS: RAMP expression was examined by real-time quantitative RT-PCR, immunohistochemistry and western blotting. Inhibition of RAMP expression was performed by siRNA-mediated knockdown. The functional effects of RAMP on cell kinetics were measured by cell viability assay, colony formation assay and flow cytometry. Cell lines stably expressing RAMP were established to investigate the oncogenic effects of RAMP in vitro. RESULTS: Ramp was readily expressed in all seven gastric cancer cell lines and was significantly increased in human gastric cancer tissues when compared with their adjacent non-cancerous tissues (P<0.001). In keeping with this, expression of RAMP protein was higher in gastric cancer tissues compared with their adjacent non-cancerous tissues, whereas moderate protein expression were noted in intestinal metaplasia. Knockdown of RAMP in gastric cancer cells significantly reduced cell proliferation (P<0.01) and soft agar colony formation (P<0.001), but induced apoptosis and G(2)/M arrest. In additional, knockdown RAMP induced cell apoptosis is dependent on functional accumulation of p53 and p21 and induction of cleaved caspases-9, caspases-3 and PARP. Strikingly, overexpression of RAMP promoted anchorage-independent cell growth in soft agar. CONCLUSION: Our findings demonstrate that RAMP plays an oncogenic role in gastric carcinogenesis. Inhibition of RAMP may be a promising approach for gastric cancer therapy.

Postoperative staging of pancreatic cancer.

Pancreatic cancer is a devastating disease with a 5-year survival rate of 3%-5%. The mortality of pancreatic cancer is almost identical with its incidence. The vast majority are pancreatic ductal adenocarcinomas. It is typically a tumour of the elderly. The main risk factor is smoking. Clinical and histopathological studies have identified pancreatic cancer precursor lesions. These include pancreatic intraepithelial neoplasia (PanIN), intraductal papillary mucinous neoplasia (IPMN) and mucinous cystic neoplasm (MCN). To improve patient prognosis, surgical interventions have become more aggressive, including pancreaticoduodenectomy and more or less radical lymphadenectomy. Following surgery, it is the surgical pathologist who provides valuable information regarding the exact tumour localization, histological tumour type, grading, completeness of resection, nodal status and the presence of precursor lesions. Although many tissue-based prognostic biomarkers have been characterized and can be studied by immunohistochemistry or molecular biological techniques, their impact on patient management and treatment is still limited. More recently proteomic profiling has raised hopes for early cancer detection, thereby improving the prognosis of pancreatic cancer patients.

Hepatocyte-specific Smad7 deletion accelerates DEN-induced HCC via activation of STAT3 signaling in mice.

TGF-ß signaling in liver cells has variant roles in the dynamics of liver diseases, including hepatocellular carcinoma (HCC). We previously found a correlation of high levels of the important endogenous negative TGF-ß signaling regulator SMAD7 with better clinical outcome in HCC patients. However, the underlying tumor-suppressive molecular mechanisms are still unclear. Here, we show that conditional (TTR-Cre) hepatocyte-specific SMAD7 knockout (KO) mice develop more tumors than wild-type and corresponding SMAD7 transgenic mice 9 months after diethylnitrosamine (DEN) challenge, verifying SMAD7 as a tumor suppressor in HCC. In line with our findings in patients, Smad7 levels in both tumor tissue as well as surrounding tissue show a significant inverse correlation with tumor numbers. SMAD7 KO mice presented with increased pSMAD2/3 levels and decreased apoptosis in the tumor tissue. Higher tumor incidence was accompanied by reduced P21 and upregulated c-MYC expression in the tumors. Activation of signal transducer and activator of transcription factor 3 signaling was found in Smad7-deficient mouse tumors and in patients with low tumoral SMAD7 expression as compared with surrounding tissue. Together, our results provide new mechanistic insights into the tumor-suppressive functions of SMAD7 in hepatocarcinogenesis.

Expression of metallothionein II in intestinal metaplasia, dysplasia, and gastric cancer.

Differential display is a valuable tool for the identification of differentially expressed genes in human carcinogenesis and development. The search for differentially expressed genes in gastric cancer and its premalignant lesions may help to define molecular alterations in the gastric mucosa that may precede the development of gastric cancer. Using the differential display technique, we identified a cDNA fragment, encoding metallothionein (MT) IIa mRNA. We performed immunohistochemical analysis using a monoclonal antibody directed against human MT and tissues obtained from 34 patients with gastric cancer and 20 healthy individuals to determine the expression and localization of MT in gastric cancer and its associated premalignant lesions and to correlate our findings with histomorphological features and Helicobacter pylori status. In addition, MT expression was assessed in gastric tissues obtained from patients with gastric cancer and first-degree relatives of patients with gastric cancers and healthy individuals using reverse transcription-PCR analysis. Northern blot analysis confirmed the overexpression of MT IIa in gastric cancer. In the normal gastric tissues, no MT immunoreactivity was observed at the superficial gastric epithelium toward the top of gastric glands. However, MT immunoreactivity was detected at the foveolar neck of the gastric glands. Immunohistochemical analysis revealed an intense MT immunoreactivity in gastric cancer cells, independent of tumor stage, grade of differentiation, or tumor type. Furthermore, areas of dysplasia and intestinal metaplasia also exhibited intense MT immunoreactivity. Reverse transcription-PCR analysis of gastric biopsies obtained from first-degree relatives of patients with gastric cancer revealed the frequent expression of MT Ia in this high-risk group as compared with healthy subjects (P < 0.01). The overexpression of MT in gastric cancer and the expression of MT in intestinal metaplasia and dysplasia, as well as the expression of MT in the gastric mucosa of first-degree relatives of patients with gastric cancer, point to a role for MT in the early process of malignant transformation of the gastric mucosa.

Expression of carbonic anhydrase IX in human pancreatic cancer.

BACKGROUND: Carbonic anhydrase IX has been linked to cancer development and progression. AIM: To analyse carbonic anhydrase IX expression and anhydrase inhibition in pancreatic cancer and to correlate these findings with p53 expression and microvessel density. MATERIALS AND METHODS: Seventy-seven pancreatic cancers were examined (43 males, 34 females; mean age, 64 years). The anti-carbonic anhydrase IX M75 antibody was used for immunohistochemistry and Western blot analysis. Microvessels were visualized using the anti-CD34 antibody, and p53 expression in cancer cells was assessed with a specific anti-p53 antibody. Quantitative polymerase chain reaction was performed in order to assess carbonic anhydrase IX mRNA levels in the pancreas. Furthermore, pancreatic cancer cell lines were treated with acetazolamide, a carbonic anhydrase inhibitor. RESULTS: In the normal pancreas, carbonic anhydrase IX immunoreactivity was observed at the basolateral membrane of ductal cells in 24 cases (31%). Carbonic anhydrase IX expression was found at the membrane and in the cytoplasm of pancreatic cancer cells in 16 pancreatic cancers (21%). Carbonic anhydrase IX expression was independent of the localization, stage, size, metastases and differentiation of the tumour. p53 expression was significantly more frequent in poorly differentiated cancers (P=0.0323); however, p53 expression and microvessel density were independent of carbonic anhydrase IX expression. Overall, carbonic anhydrase IX expression was not altered in pancreatic cancers vs. adjacent normal pancreatic tissue as assessed by Western blot and quantitative polymerase chain reaction analysis. However, incubation of pancreatic cancer cell lines with acetazolamide led to a significant inhibition of cell proliferation in AsPC-1 and PANC-1 pancreatic cancer cells. CONCLUSION: Carbonic anhydrase IX expression is observed in both ductal epithelial and cancer cells of the pancreas. Although the expression of carbonic anhydrase IX in pancreatic cancer is not associated with angiogenesis or advanced disease, it may well be a target for carbo-anhydrase inhibitors in a subset of pancreatic cancers.

Effect of Helicobacter pylori eradication on expression of cyclin D2 and p27 in gastric intestinal metaplasia.

BACKGROUND AND AIMS: Cyclins and cyclin-dependent kinase inhibitors play a crucial role in the control of cell cycle transitions. Enhanced expression of cyclin D2 and reduced expression of p27kip1 (p27) have been implicated in the pathogenesis of cancer. Because intestinal metaplasia has been regarded as a pre-malignant lesion, we investigated the expression of cyclin D2 and p27 in Helicobacter pylori-associated chronic gastritis with and without intestinal metaplasia, and followed the changes after H. pylori eradication. METHODS: Expression of cyclin D2 and p27 was studied by immunohistochemistry in 59 patients (including 35 patients with intestinal metaplasia) and in 10 gastric cancer patients. Among them, 29 H. pylori-infected patients had serial gastric biopsies taken before and at 1-year after eradication of H. pylori. RESULTS: Expression of cyclin D2 was significantly higher in gastric cancers when compared to their adjacent non-tumour tissues (median score 3 vs. 1, P=0.015). Over-expression of cyclin D2 was detected in H. pylori-associated chronic gastritis and intestinal metaplasia, which was reduced after eradication of the organism (median score 2 vs. 1, P=0.037 in chronic gastritis; median score 2 vs. 0, P=0.008 in intestinal metaplasia). While the normal gastric mucosa showed strong p27 expression, five of the 10 gastric cancer tissues exhibited reduced p27 expression (P=0.039). Diminished p27 expression was also seen in intestinal metaplasia, which was restored 1-year after H. pylori eradication (eight out of 16 vs. one out of 16, P=0.018). Reduced expression of p27 was frequently associated with increased cyclin D2 expression in H. pylori-associated intestinal metaplasia (P=0.02). CONCLUSION: Over-expression of cyclin D2 and reduced expression of p27 are closely linked to H. pylori-associated intestinal metaplasia. Eradication of H. pylori infection reverses the aberrant expression of cyclin D2 and p27 in intestinal metaplasia.

Induction and expression of cyclin D3 in human pancreatic cancer.

PURPOSE: Cyclins play a key role in the control and regulation of the cell cycle. The role of cyclins in the pathogenesis of pancreatic cancer is largely unknown. METHODS: Using Northern blot analysis, polymerase chain reaction (PCR) and immunohistochemistry, we examined the expression of cyclins D1, D2, and D3 in human pancreatic cancer and studied the induction of these cyclins by growth factors in pancreatic cancer cell lines. RESULTS: We now report that cyclin D1 and D3 mRNAs are expressed in human pancreatic cancer cell lines, and that the expression of cyclin D3 is enhanced in pancreatic cancer cells by amphiregulin, a member of the epidermal growth factor family. Cyclins D1 and D3 are also expressed in normal and malignant pancreatic tissues. However, while the normal pancreas and pancreatic cancers express cyclin D2 as determined by reverse-transcriptase PCR, we could not detect cyclin D2 mRNA by either Northern blot analysis or reverse transcriptase PCR in the two pancreatic cancer cell lines. Immunohistochemical analysis revealed the expression of cyclin D3 in pancreatic cancer cells. CONCLUSIONS: These findings suggest that D-type cyclins are differentially expressed in pancreatic cancer and that the aberrant activation of the EGF receptor in human pancreatic cancer by amphiregulin may lead to the progression of the cell cycle via induction of cyclin D3 expression, thus contributing to the growth advantage of these transformed cells.

Molecular alterations in gastric cancer: the role of Helicobacter pylori.

Helicobacter pylori has been classified as a human carcinogen contributing to the pathogenesis of gastric cancer. Extensive sero-epidemiological studies and recently animal experiments have established a close link between H. pylori infection and the development of gastric cancer. However, the molecular changes induced by H. pylori directly or the concomitant chronic inflammation of the gastric mucosa, and the impact of these changes on the subsequent development of gastric cancer, remain largely unknown. This review will highlight the present knowledge on the molecular pathogenesis of gastric cancer with an emphasis on molecular and genetic alterations which develop due to chronic infection of the gastric mucosa by H. pylori.

Validity of a Helicobacter pylori stool antigen assay for the assessment of H. pylori status following eradication therapy.

BACKGROUND: A Helicobacter pylori stool antigen (HpSA) test has been proposed as a valid alternative to the 13C-urea breath test (13C-UBT) for the non-invasive detection of H. pylori infection in primary diagnosis. Published reports show conflicting results with regard to the test's diagnostic accuracy after eradication therapy. The aim of the present study was to assess the diagnostic value of the HpSA test and to determine the optimal discriminating cut-off value in patients following H. pylori eradication therapy. METHOD: Stool samples were collected and the 13C-UBT was performed in 113 patients 4-6 weeks after eradication therapy. A validated test protocol for the 13C-UBT was used. Stool specimens were analysed with the Premier Platinum HpSA enzyme immunoassay (EIA). A receiver operator characteristics (ROC) analysis was performed to define the optimal cut-off value on the basis of the results of the 13C-UBT. RESULTS: The results of the 13C-UBT showed that H. pylori eradication was successful in 83/113 (73%) patients. According to the manufacturer, the cut-off value for the HpSA test is 0.14 optical density, but this does not appear to be valid after eradication therapy (sensitivity 76.7%, specificity 98.8%). On the basis of ROC analysis, the optimal cut-off value after therapy was determined to be 0.11 optical density, giving a sensitivity of 93.3% and a specificity of 93.9%. CONCLUSION: The HpSA test is a valid test for the assessment of H. pylori status after eradication therapy, provided an adjusted cut-off value is applied.

Analysis of K-ras gene mutations in rare pancreatic and ampullary tumours.

OBJECTIVE: Mutation of the K-ras oncogene is a frequent event in pancreatic ductal carcinogenesis and it is believed to occur at an early stage in the development of pancreatic cancer. However, little is known of the role of K-ras mutations in rare pancreatic epithelial neoplasms, endocrine tumours or other non-epithelial tumours of the pancreas. Furthermore, limited data are available regarding the role of K-ras mutations in the pathogenesis of ampullary tumours. DESIGN AND METHODS: Using single-strand conformation polymorphism (SSCP) and direct sequencing of polymerase chain reaction (PCR)-amplified fragments, we analysed codons 12 and 13 for the presence of oncogenic mutations of the K-ras oncogene. Tissues were obtained from patients undergoing tumour resection for various rare pancreatic or ampullary neoplasms (number of cases in brackets): ampullary adenoma (1), neuro-endocrine tumour (3), malignant fibrous histiocytoma of the pancreas (1), pancreatic cystadenocarcinoma (1), serous cystadenoma (1), and primary and metastatic adenocarcinoma of the ampulla (5) and pancreas (3). RESULTS: K-ras gene mutations at codon 12 were detected in both pancreatic adenocarcinomas and in the metastatic lesion, whereas two ampullary cancers harboured a point mutation at codon 13: GGC-->GGG and GGC-->GGT. None of the other tumours exhibited a K-ras gene mutation at codons 12 or 13. CONCLUSION: Pancreatic tumours other than ductal adenocarcinoma of the pancreas do not harbour mutations of the K-ras oncogene. In addition, ampullary adenocarcinomas may present with codon 13 mutations; however, these mutations were not associated with amino acid substitution. Therefore, K-ras gene mutations seem to be a specific genetic alteration contributing to the pathogenesis of pancreatic ductal adenocarcinoma.