A case of intraductal papillary neoplasm of the bile duct preoperatively diagnosed using contrast-enhanced endoscopic ultrasonography.

A 71-year-old man was referred to our hospital and was diagnosed with jaundice and a liver function disorder. Although we suspected an intraductal papillary neoplasm of the bile duct (IPNB)-derived caudate branches on the basis of contrast-enhanced CT, MRI, and endoscopic retrograde cholangiopancreatography, we could not clearly identify the tumor. Therefore, we examined the lesion using endoscopic ultrasonography (EUS). We could visualize an iso-hyperechoic elevated tumor in the caudate branches. The tumor was observed as a hypervascular lesion using contrast-enhanced EUS, which is useful in preoperatively diagnosing IPNB and detecting the presence of lesions.

KNK437 downregulates heat shock protein 27 of pancreatic cancer cells and enhances the cytotoxic effect of gemcitabine.

BACKGROUND: Our previous proteomic study demonstrated that expression of heat shock protein 27 (HSP27) is upregulated in gemcitabine (GEM)-resistant pancreatic cancer cells and that it suppressed the cytotoxic effect of GEM on the cells. This report describes the benefits of a treatment strategy combining the HSP inhibitor KNK437 with GEM for GEM-resistant pancreatic cancer cells. METHODS: We used 2 human pancreatic cancer cell lines, GEM-sensitive KLM1 and GEM-resistant KLM1-R. KLM1-R was treated with KNK437, and we examined the expression of HSP27 by Western blotting. The cytotoxicity of GEM and KNK437 for KLM1-R was investigated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. RESULTS: The expression of HSP27 in KLM1-R was dramatically reduced by KNK437. In addition, the in vitro antitumor cytotoxic effect of GEM on KLM1-R was enhanced by combination treatment with KNK437 compared to GEM alone. CONCLUSION: This study supports the potential therapeutic benefits of a treatment strategy combining KNK437 with GEM.

Genetic diagnosis of pancreatic cancer using specimens obtained by EUS-FNA.

We review the current situation concerning molecular biological analysis in respect of pancreatic cancer, using specimens obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). K-ras, p53, p16, DPC4/SMAD4, telomerase activity are used for discrimination between tumor-forming pancreatitis and pancreatic cancer. Examination of heat shock protein (HSP) 27, ribonucleotide reductase, and other factors are examined in order to test the sensitivity to Gemcitabin. Comparative genomic hybridization analysis for pancreatic cancer specimens obtained by EUS-FNA was reported to be useful for evaluate the biological characteristics of pancreatic cancer before treatment. It is expected that the genetic diagnosis using EUS-FNA specimens will not only positively contribute to improving the diagnostic performance, but it will also provide valuable information for carrying out tailor-made treatment.

Unilateral versus bilateral drainage using self-expandable metallic stent for unresectable hilar biliary obstruction.

BACKGROUND: There is no consensus on the choice of either unilateral or bilateral drainage in stent placement for patients with unresectable hilar biliary obstruction. The aim of the present study was to clarify which drainage method is superior. METHODS: We retrospectively reviewed 82 patients with hilar biliary obstruction who underwent metallic stenting. These patients were divided into a unilateral drainage group (Uni group) and a bilateral drainage group (Bi group). RESULTS: There was no significant difference between the groups in median survival time, median stent patency period, and median complication-free survival time. The most frequent complication was stent obstruction, followed by cholangitis. Liver abscess was found at a higher frequency in the Bi group (17.6%) than in the Uni group (1.5%) (P=0.0266). There was no significant difference between the groups in the occurrence of two or more complications (P=0.247), life-threatening severe complications (P=0.0577), and stent obstruction by sludge (P=0.0912). CONCLUSION: When compared with bilateral biliary drainage, unilateral biliary drainage is associated with a lower incidence of liver abscess as well as a comparable outcome of stent patency time and complication-free survival. We therefore propose that hilar biliary obstruction can be treated first by unilateral drainage with a metallic stent and by bilateral drainage only in patients who develop cholangitis in the contralateral biliary tree.

Successful retrieval of an impacted mechanical lithotripsy basket: a case report.

We report the successful retrieval of an impacted mechanical lithotripsy basket. In a patient with two large common bile duct stones, the basket with the entrapped stone was impacted within the mid-common bile duct. We then attempted to use another mechanical lithotripter; however the central wire of the basket fractured at the handle portion. Grasping a few wires of the impacted basket with rat-tooth forceps allowed the wires of the basket to slip away from the stone. The present report describes the safe and effective use of rat-tooth forceps in the management of an impacted lithotripter basket.

Double balloon endoscope facilitates endoscopic retrograde cholangiopancreatography in roux-en-y anastomosis patients.

Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for the treatment of patients with pancreaticobiliary disorders, but endoscopic therapy is very difficult to carry out in patients with a Roux-en-Y anastomosis. We herein present the results of ERCP for patients with a Roux-en-Y anastomosis using a double-balloon endoscope. Six patients (six men with a mean age of 69 years) who had undergone prior gastric resection with Roux-en-Y reconstruction were enrolled in the present study and underwent ERCP and associated procedures. ERCP was carried out with a double balloon endoscope, which has one balloon attached to the tip of the endoscope and another attached to the distal end of the soft overtube. In all patients, entering the Y loop was successfully accomplished, and the papilla of Vater was also reached in all cases (100%). Cannulation was successful in four patients (66.7%). The final diagnosis was choledocholithiasis in two patients, biliary fistula in one patient and pancreatic cancer in one patient. A needle-knife precut papillotomy was carried out after placement of a bile duct stent in two patients, and injection of N-butyl-2-cyanoacrylate into a biliary fistula was carried out in one patient. None of the patients suffered from any complications. A double balloon endoscope is therefore considered to be useful for carrying out ERCP and associated procedures in patients with a Roux-en-Y anastomosis.

ERCP using double-balloon endoscopes in patients with Roux-en-Y anastomosis.

INTRODUCTION: Endoscopic retrograde cholangiopancreatography (ERCP) and associated procedures are difficult to perform in patients with a Roux-en-Y reconstruction. Therefore, at present, at many institutions, ERCP is not generally performed for those with a Roux-en-Y anastomosis. METHODS: However, double-balloon endoscopes (DBEs) have dramatically changed this situation. RESULTS: The use of a DBE enables an endoscopic approach into the deeply situated small intestine, which has been difficult with a conventional endoscope. Therefore, ERCP for patients with a Roux-en-Y anastomosis has been attempted using a DBE, and good results have been reported. CONCLUSION: The development of DBEs has created the possibility of performing ERCP for patients with Roux-en-Y reconstruction in whom an endoscopic approach has conventionally been believed to be difficult.

Heat-shock protein 27 plays the key role in gemcitabine-resistance of pancreatic cancer cells.

Pancreatic cancer is one of the most fatal types of cancer in developed countries. Most patients have locally advanced or metastatic cancerous lesions when they are diagnosed, due to the progressive, invasive and metastatic capacity of this disease to liver, lymph nodes and distant organs during early stages. Although the only curative therapy is complete surgical resection, the disease has usually already progressed by the time of diagnosis, and the majority of patients have metastatic disease. Therefore, palliative chemotherapy remains the only therapy for patients with progressive disease. Gemcitabine has been used for pancreatic cancer as the most effective anticancer drug. However, there are many cases resistant to gemcitabine. Thus, a better understanding of the molecular mechanisms of resistance to gemcitabine is essential to allow it to be used more effectively. Our previous proteomic studies demonstrated that the expression of heat-shock protein 27 (HSP27) was increased in gemcitabine-resistant pancreatic cancer cells and this might play a role in determining the sensitivity of pancreatic cancer to gemcitabine. Increased HSP27 expression in tumor specimens was related to resistance to gemcitabine and a shorter survival period in patients with pancreatic cancer. Furthermore, it has been shown that treatment strategies combining the HSP inhibitor KNK437 or interferon-γ (IFN-γ) with gemcitabine, were effective in gemcitabine-resistant pancreatic cancer cells in vitro. Furthermore, combined therapy of gemcitabine with IFN-γ of gemcitabine-resistant pancreatic cancer-bearing nude mice showed synergistic therapeutic effects on gemcitabine-resistant pancreatic cancer bearers. In this review, we summarize the current understanding of HSP27 and its role in gemcitabine resistance.

Clinical impact of endoscopic papillectomy for benign-malignant borderline lesions of the major duodenal papilla.

BACKGROUND AND PURPOSE: The present study retrospectively analyzed the clinical impact of endoscopic papillectomy on the selection of a treatment strategy for patients with benign-malignant borderline lesions of the major duodenal papilla. PATIENTS AND METHODS: Between November 1995 and July 2009, 28 patients were selected for endoscopic papillectomy. The clinical impact of endoscopic papillectomy was assessed. Snare resection was performed in a radical fashion. RESULTS: An endoscopic papillectomy was technically feasible in all patients. En bloc excision was achieved in 22 cases (79%). The final histopathological diagnoses of the endoscopic specimen were 17 adenoma (61%), 7 carcinoma in adenoma (25%), and 4 adenocarcinoma (14%). Two out of the four adenocarcinoma cases were referred for surgery. The other two patients with negative margins have not experienced recurrences during the follow-up period. A residual tumor was detected in 1 out of 17 cases (6%) of adenoma and 2 out of 7 cases (29%) of carcinoma in adenoma. CONCLUSIONS: Endoscopic papillectomy is therefore considered to be an effective treatment for patients with a benign-malignant borderline lesion of the major duodenal papilla. This method also has an important clinical impact because it provides an accurate diagnosis, aids in the selection of an appropriate treatment strategy, and reduces unnecessary surgery.

Proteomic differential display analysis for TS-1-resistant and -sensitive pancreatic cancer cells using two-dimensional gel electrophoresis and mass spectrometry.

TS-1 is an oral anticancer agent containing two biochemical modulators for 5-fluorouracil (5-FU) and tegafur (FT), a metabolically activated prodrug of 5-FU. TS-1 has been recognized as an effective anticancer drug using standard therapies for patients with advanced pancreatic cancer along with gemcitabine. However, a high level of inherent and acquired tumor resistance to TS-1 induces difficulty in the treatment. To identify proteins linked to the TS-1-resistance of pancreatic cancer, we profiled protein expression levels in samples of TS-1-resistant and -sensitive pancreatic cancer cell lines by using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The cytotoxicity of a 5-FU/5-chloro-2,4-dihydroxypyridine (CDHP) combination towards pancreatic cancer cell lines was evaluated by MTS assay. Panc-1, BxPC-3, MiaPaCa-2 and PK59 showed high sensitivity to the 5-FU/CDHP combination (TS-1-sensitive), whereas PK45p and KLM-1 were much less sensitive (TS-1-resistant). Proteomic analysis showed that eleven spots, including T-complex protein 1 subunit beta, ribonuclease inhibitor, elongation factor 1-delta, peroxiredoxin-2 and superoxide dismutase (Cu-Zn), appeared to be down-regulated, and 29 spots, including hypoxia up-regulated protein 1, lamin-A/C, endoplasmin, fascin and annexin A1, appeared to be up-regulated in TS-1-resistant cells compared with -sensitive cells. These results suggest that the identified proteins showing different expression between TS-1-sensitive and -resistant pancreatic cancer cells possibly relate to TS-1-sensitivity. These findings could be useful to overcome the TS-1-resistance of pancreatic cancer cells.

Heat-shock protein 27 is phosphorylated in gemcitabine-resistant pancreatic cancer cells.

BACKGROUND: Gemcitabine (2'-deoxy-2'-difluorodeoxycytidine: Gemzar) (GEM) appears to be the only effective anticancer drug for pancreatic cancer, but it has little impact on outcome due to a high level of inherent and acquired tumor resistance. Our previous proteomic study demonstrated that the expression of three spots of heat-shock protein 27 (HSP27) was increased in GEM-resistant pancreatic cancer cells and could play a role in determining the sensitivity of pancreatic cancer to GEM. MATERIALS AND METHODS AND RESULTS: In the present study, using one-dimensional and two-dimensional Western blotting, we elucidated that these three spots of HSP27 were phosphorylated in GEM-resistant pancreatic cancer cell line, KLM1-R. CONCLUSION: Phosphorylated HSP27 may play an important role in the resistance to GEM, and it could also be a possible biomarker for predicting the response of pancreatic cancer patients to treatment with GEM.

Identification of up- and down-regulated proteins in gemcitabine-resistant pancreatic cancer cells using two-dimensional gel electrophoresis and mass spectrometry.

The prognosis of patients with pancreatic cancer is very poor because of late diagnosis and the lack of response to various therapies. Pancreatic cancer is generally resistant to chemotherapy and is highly fatal. Gemcitabine (GEM) appears to be the only effective agent for treatment of pancreatic cancer. However, a high level of inherent and acquired tumor resistance makes the clinical impact of GEM modest. Proteomic differential display analysis for GEM-sensitive human pancreatic adenocarcinoma cell line KLM1 and GEM-resistant KLM1-R cells by using two-dimensional gel electrophoresis and liquid chromatography tandem mass spectrometry produced 33 protein spots. Of these, 23 were up-regulated and 10 were down-regulated in KLM1-R compared to KLM1 cells. The up-regulated proteins include acidic leucine-rich nuclear phosphoprotein 32 family member A, reticulocalbin-1, gamma-synuclein, microtubule-associated protein RP/EB family, sialic acid synthase, peptidyl-prolyl cis-trans isomerase A, far upstream element-binding protein 2 and catalase. The down-regulated proteins include far upstream element-binding protein 1, gamma-synuclein, galectin-1 and stathmin. Two spots of heat-shock protein 27 were up-regulated in KLM1-R cells. These results suggest an important complementary role for proteomics in the identification of proteins which may play a role in the poor response of pancreatic cancer to GEM.

A proteomic profiling of gemcitabine resistance in pancreatic cancer cell lines.

Pancreatic cancer is one of the most highly fatal cancers and is generally resistant to chemotherapy. Currently, gemcitabine appears to be the only effective agent for its treatment and is the preferred first-line therapy. However, the clinical impact of gemcitabine remains modest due to a high level of inherent and acquired tumor resistance. We investigated protein expression in gemcitabine-resistant and -sensitive human pancreatic adenocarcinoma cell lines by proteomics. Tumor cell proteins were separated by two-dimensional gel electrophoresis, then the protein spots that showed increased or decreased expression in gemcitabine-sensitive cell lines were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and Western blotting. Nine out of ten proteins showing differential expression in gemcitabine-resistant and -sensitive cell lines were identified, confirming an increase in heat shock protein 27 (HSP27) and a decrease in nucleophosmin (NPM) in the resistant lines. These results suggest that HSP27 and NPM may play a role in the poor response of pancreatic cancer to gemcitabine.