Detection of c-Ki- ras point mutation from pancreatic juice

Summary Cytological diagnosis of pancreatic carcinoma sometimes poses difficulties in distinguishing malignant from benign cells. Recent molecular study of pancreatic carcinoma has revealed a very high incidence of a point mutation of the c-Ki-ras oncogene at codon 12 in this neoplasm. To take advantage of this technique for the diagnosis of pancreatic carcinoma, we attempted to amplify the c-Ki-ras gene from endoscopically obtained pancreatic juice by isolation of DNA and polymerase chain reaction (PCR) coupled with restriction fragment length polymorphism (RFLP). PCR was possible in approx 70% of the cases. A point mutation was nonradioisotopically detected in 4 of 6 pancreatic carcinomas and in one intraductal papillary neoplasm, whereas no mutation was detected in other cases. Thus, this method was thought to be useful for the diagnosis of pancreatic carcinoma.     

Neonatal hyperglycaemia and abnormal development of the pancreas

Transient and permanent neonatal diabetes mellitus (TNDM and PNDM) are rare conditions occurring in around 1 per 300,000 live births. In TNDM, growth-retarded infants develop diabetes in the first few weeks of life, only to go into remission after a few months with possible relapse to permanent diabetes usually around adolescence or in adulthood. In PNDM, insulin secretory failure occurs in the late fetal or early postnatal period. The very recently elucidated mutations in KCNJ11 and ABCC8 genes, encoding the Kir6.2 and SUR1 subunits of the pancreatic K(ATP) channel involved in regulation of insulin secretion, account for a third to a half of the PNDM cases. Molecular analysis of chromosome 6 anomalies and the KCNJ11 and ABCC8 genes encoding Kir6.2 and SUR1 provides a tool for distinguishing transient from permanent neonatal diabetes mellitus in the neonatal period. Some patients (those with mutations in KCNJ11 and ABCC8) may be transferred from insulin therapy to sulphonylureas.     

Clinical significance of cathepsin E in pancreatic juice in the diagnosis of pancreatic ductal adenocarcinoma

BACKGROUND: It has been reported that cathepsin E (CTSE) is a non-secretory and intracellular aspartic proteinase found in the superficial epithelial cells of the stomach and that it is also expressed in pancreatic ductal adenocarcinoma. We evaluated the diagnostic value of CTSE in the pancreatic juice in the diagnosis of pancreatic ductal adenocarcinoma compared with that of CA19-9, carcinoembryonic antigen (CEA) and K-ras mutations. METHODS: One hundred and one patients (25 with pancreatic ductal adenocarcinoma and 76 with chronic pancreatitis) were examined for the diagnostic significance of CTSE in the pancreatic juice in the diagnosis of pancreatic ductal adenocarcinoma. Forty of 101 patients (15 with pancreatic ductal adenocarcinoma and 25 with chronic pancreatitis) were examined to compare the diagnostic value of various tumor markers in the pancreatic juice, namely CA19-9, CEA, K-ras mutations and CTSE. RESULTS: The detection frequency of CTSE was significantly higher in patients with pancreatic ductal adenocarcinoma (64.0%) than in patients with chronic pancreatitis (7.9%; chi2 = 34.76; P < 0.0001). The sensitivity, specificity and diagnostic accuracy of CTSE in the pancreatic juice for pancreatic ductal adenocarcinoma was 66.7, 92.0 and 82.5%, respectively. These values were more efficient in comparison with those of CA19-9, CEA and K-ras mutations. The main cause of the detection failure of CTSE in pancreatic ductal adenocarcinoma was obstruction of the main pancreatic duct. Sensitivity was 85.7% in patients without obstruction of the main pancreatic duct. CONCLUSIONS: Cathepsin E in the pancreatic juice is a novel marker for a definitive diagnosis of pancreatic ductal adenocarcinoma.     

Dissociation of CCK-8-Induced fluid secretion from protein secretion by ion-transport blockers in rat pancreas

The effects of ion-transport blockers on CCK-8-induced protein output and concomitant fluid secretion were compared in isolated, perfused normal and hypertrophied rat pancreata. In the normal pancreas, perfusion with ouabain (1 mM), amiloride (1 mM), furosemide (1 mM), or SITS (0.1 mM) caused corresponding inhibition of both fluid and protein secretion that was induced by 100 pM CCK-8. Hypertrophy of the pancreas was produced by oral administration of a synthetic protease inhibitor (FOY-305) once a day for 3 wk. In the hypertrophied pancreas, perfusion with ouabain (0.1 or 1 mM) or amiloride (0.1 mM or 1 mM) decreased CCK-8-induced fluid secretion without changing CCK-8-induced protein output. Perfusion with furosemide (1 mM) inhibited both fluid and protein secretion induced by CCK-8, but the amount of inhibition of fluid secretion was much greater than that of protein secretion. Perfusion with SITS (0.1 mM) significantly decreased CCK-8-induced fluid secretion but not protein secretion. These results indicate that in contrast to a normal rat pancreas, the coupling of fluid and protein secretion induced by CCK-8 can be disrupted by experimental procedures that induce hypertrophy in the rat pancreas.     

Distal pancreatectomy: en-bloc splenectomy vs spleen-preserving pancreatectomy

Distal pancreatectomy with en-bloc splenectomy has been considered the standard technique for management of benign and malignant pancreatic disorders. However, splenic preservation has recently been advocated. The aim of this study was to review the experiences of distal pancreatectomy using the open or the laparoscopic approach and to critically discuss the need to perform splenectomy. Original articles published in the English literature of peer-reviewed medical journals were selected for detailed analysis. In patients with malignant neoplasms in the body-tail of the pancreas, splenectomy has a negative influence on long-term survival after resection. The incidence of diabetes after spleen-preserving distal pancreatectomy for chronic pancreatitis is less than after en-bloc splenectomy. Spleen salvage eliminates the risk of overwhelming infections. Laparoscopic spleen-preserving distal pancreatectomy is feasible and safe. Laparoscopic spleen-preserving distal pancreatectomy may be preferable for the advantages of a minimally invasive approach.     

Effects of Taxotere on invasive potential and multidrug resistance phenotype in pancreatic carcinoma cell line SUIT-2

INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relationship between expression of multidrugresistance (MDR) phenotype P-glycoprotein (P-gp)and the malignant properties of tumors, but theresults are often conflicting[1-8]. The difference intumor types or MDR phenotype induced by specificagents might account for this discrepancy. Taxotere(TXT), a member of the family of taxanes, hasantitumor activity through its effect of promotingthe polymerization of tubulin[9,10].     

What's new in pancreatic cancer treatment?

Pancreatic cancer represents a major challenge to oncologists because of its high chemoresistant nature and dismal outcomes. Conventional therapy for advanced disease relied for a long time on palliative 5‐fluorouracil (5‐FU)‐based chemotherapy, but with unsatisfactory results. The introduction of the novel antimetabolite gemcitabine provides new optimism for patients with advanced pancreatic cancer, as multiple clinical trials have demonstrated the superiority of gemcitabine over 5‐FU and other agents for these patients. The benefits of gemcitabine over conventional therapies include improved response rate and enhanced survival, as well as improvement in disease‐related symptoms and quality of life in these patients. With these data, gemcitabine is widely accepted worldwide as the therapy of choice by many oncologists for advanced pancreatic cancer. The current review presents an overview of the clinical studies of gemcitabine over the past decade for the treatment of patients with advanced pancreatic cancer. Other investigational regimens or uses (e.g., fixed dose‐rate infusion, intraarterial infusion, adjuvant use, chemo‐radiation, etc) are also reviewed.     

Surgical management of endocrine tumor of the pancreas in Japan

Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy (JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery, and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion; the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor.     

Detection of circulating tumor cells in patients with pancreatic cancer: a preliminary result

Background/Purpose

It has been reported that circulating tumor cells (CTCs) can be used to predict survival in metastatic breast cancer. In this preliminary study, we examined the level of CTCs in pancreatic cancer (PC) patients to elucidate whether we could predict survival in PC.

Methods

The eligible subjects, at Tokyo Medical University Hospital, were 26 patients with PC, 11 with chronic pancreatitis, and 10 healthy volunteers. Three PC patients underwent surgery, 18 patients (who were stage IV) were treated with gemcitabine (GEM), and 5 patients received best supportive care (BSC).

Results

The CTC count was 1/7.5 ml blood or higher (defined as positive) in 11 of the 26 patients (42%; mean, 16.9/7.5 ml blood; range, 1-105/7.5 ml blood). Gemcitabine was administered to 6 of the 11 CTC-positive patients (3.8 courses on average). The treatment was continued for more than three courses in 2 patients, in both of whom the CTC count was only 1/7.5 ml blood. Operation was performed in 1 of the 11 CTC-positive patients. The remaining 4 patients of the 11 CTC-positive patients received only BSC. CTC was negative in 15 patients with PC (stage II, 1; stage III, 1; stage IVa, 7; and stage IVb, 6) and in the subjects with benign conditions. The median survival times (MSTs) of the CTC-positive and-negative patients were 110.5 and 375.8 days (P < 0.001). When the analysis was limited to the 14 stage-IVb patients, the MSTs of the CTC-positive and-negative patients were 52.5 and 308.3 days (P < 0.01).

Conclusions

The present study demonstrated that the detection of CTCs in peripheral blood may be useful to predict prognosis in patients with PC.     

On the accumulation of alloxan in the pancreatic β-cells

Summary Autoradiographic studies revealed that the radioactivity in the pancreatic islets was higher than in any other mouse tissue after intravenous injections of tracer doses of ¹⁴C-2-alloxan. The concentration of radioactivity in the endocrine pancreas concerned a great majority of the cells indicating that at least cells were involved. The uptake of the radioisotope in the pancreatic islets was considerably reduced when the small amounts of ¹⁴C-2-alloxan were complemented with carrier to bring up the total dose to the diabetogenic level or were proceeded by higher doses of non-radioactive alloxan. There was no accumulation of radioactivity in the islets after injection of the non-diabetogenic conversion products of ¹⁴C-2-alloxan obtained in an alkaline medium and only insignificant uptake was noted after exposure of the radioactive alloxan to the reactive SH-groups of glutathione. The absence of significant radioactivity in the islets of growing animals after tracer doses of ¹⁴C-2-alloxan suggests that the ability of the cells to concentrate alloxan is confined to the adult age.This study was supported by grants from the Swedish Medical Research Council, the United States Public Health Service (AM-05759-05) and Knut and Alice Wallenbergs Stiftelse.