Inhibition of Autophagy by Deguelin Sensitizes Pancreatic Cancer Cells to Doxorubicin.

Pancreatic cancer is the fourth most common cause of cancer mortality worldwide. Furthermore, patients with pancreatic cancer experience limited benefit from current chemotherapeutic approaches because of drug resistance. Therefore, an effective therapeutic strategy for patients with pancreatic cancer is urgently required. Deguelin is a natural chemopreventive drug that exerts potent antiproliferative activity in solid tumors by inducing cell death. However, the molecular mechanisms underlying this activity have not been fully elucidated. Here we show that deguelin blocks autophagy and induces apoptosis in pancreatic cancer cells in vitro. Autophagy induced by doxorubicin plays a protective role in pancreatic cancer cells, and suppressing autophagy by chloroquine or silencing autophagy protein 5 enhanced doxorubicin-induced cell death. Similarly, inhibition of autophagy by deguelin also chemosensitized pancreatic cancer cell lines to doxorubicin. These findings suggest that deguelin has potent anticancer effects against pancreatic cancer and potentiates the anti-cancer effects of doxorubicin. These findings provide evidence that combined treatment with deguelin and doxorubicin represents an effective strategy for treating pancreatic cancer.

A new approach for Roux-en-Y reconstruction after pancreaticoduodenectomy.

BACKGROUND: Postoperative pancreatic fistula remains the most common complication of pancreaticoduodenectomy (PD) and is potentially lethal. It contributes significantly to prolonged hospitalization and mortality. In this study, we introduced a new technical approach, a modified Roux-en-Y reconstruction and evaluated its safety and feasibility. METHODS: We retrospectively reviewed the patients who had undergone PD with the modified Roux-en-Y reconstructive technique for periampullary malignancies from January 2011 to June 2012. The data on complications, hospital stay and outcomes after the modified Roux-en-Y reconstruction were analyzed. RESULTS: The reconstruction was performed in 171 patients, of whom 92 received pancreaticogastrostomy and 79 received pancreaticojejunostomy. The median duration of surgery was 4.0 hours (range 3.1-6.9) in all patients, and the median blood loss was 530 mL (range 200-2000). Sixty-nine patients were subjected to transfusions, with a median transfusion volume of 430 mL (range 200-1400). The median hospital stay of the patients was 14 days (range 11-38). Their operative mortality was zero and overall morbidity was 18.1% (31 patients). Only four patients (2.3%) developed pancreatic fistulas (grade A fistulas in two patients and grade B in two patients); no patients developed grade C fistula. None of the patients developed bile reflux gastritis. CONCLUSIONS: The modified Roux-en-Y reconstruction, which isolates biliary anastomosis from pancreatic, gastric or jejunal anastomosis, is a safe, reliable, and favorable technique. But it needs further investigation in randomized controlled trials.

[Typing and surgical treatment choice for pancreatic ductal stone].

OBJECTIVE: To explore the improvement of typing and reasonable surgical treatment for pancreatic ductal stone (PDS). METHODS: Totally 89 patients with pancreatic ductul stone treated underwent surgeries from January 2000 to December 2012 were involved into this study. There were 57 male and 32 female patients, the average age was (52 ± 23) years. According to the magnetic resonance cholangiopancreatography imaging and finding during surgery, pancreatolithiasis was classified into three types: type I, the stones were located in the main pancreatic duct; type II, the stones were located both in main and branch pancreatic duct; type III, the stones were diffusely scattered in the branch pancreatic duct; the position of PDS within pancreatic parenchyma were subtitled. In this group, 43 type I PDS were extracted with endoscopic papillotomy or endoscopic pancreatic sphincterotomy, or pancreatolithotomy plus pancreato-jejunal lateral anastomosis with wide anastomotic stoma; 39 type II cases were treated by pancreatolithotomy plus pancreato-jejunal lateral anastomosis or/and resection of pancreatic section; 7 type III PDS were managed with resection of pancreatic section. RESULTS: All surgeries were performed successfully. Among complications, 6 cases (6.7%) were pancreatic leakage which recovered after systematic non-surgical treatment, 2 cases (2.2%) were anastomotic bleeding which led to 1 death, 6 cases (6.7%) were residual pancreatolithiasis in branch pancreatic duct type. Seventy-eight patients were followed up for 6 to 131 months, 57 cases were still alive so far. Five cases were intermittent abdominal pain, 7 cases were diabetes resulted from 2 subtotal pancreatectomy and 5 distal pancreatectomy, 5 cases occurred pancreatolithiasis recurrence and 3 underwent secondary surgeries. CONCLUSIONS: The basis of this modified typing of pancreatolithiasis is the position of stone in pancreatic duct rather than pancreas parenchyma. It is more important and valuable for surgical principle of taking stones out completely and maintaining pancreatic function.

"Total arterial devascularization first" technique for resection of pancreatic head cancer during pancreaticoduodenectomy.

Integrated resection of the pancreatic head is the most difficult step in radical pancreaticoduodenectomy (RPD) in patients with the portal vein (PV) and superior mesenteric vein (SMV) invasion or oppression by the tumor. This study introduced a new idea and skill named the "total arterial devascularization first" (TADF) technique and its applications in RPD. Three arterial blood supplies of pancreatic head were obstructed before dissection of veins. The critical steps included exposure of the anterior surface of the abdominal aorta (AA) by completely transecting neural and connective tissue between superior mesenteric artery (SMA) and pancreatic mesounsinate, and transection of the mesounsinate from the origin of SMA to the root of the celiac trunk. From January 2012 through May 2013, a total of 58 patients with PV/SMV invasion or oppression underwent RPD using this technique. The median operative time was 5.1 h (ranging 4.5-8.1 h). The median intraoperative blood loss was 450 mL (ranging 200-900 mL). No intraoperative and postoperative bleeding of pancreatic head region occurred. Among the 58 patients, 21 were subjected to vessel lateral wall angiectomy or angiorrhaphy, and 10 to angiectomy and end-to-end anastomosis. The incidence of postoperative bleeding, postoperative pancreatic fistula and biliary fistula was 5.2%, 6.8%, and 1.7%, respectively. No patients died 3 months after operation. The TADF technique is a new method for intricate RPD and could improve the security of surgery and reduce intraoperative bleeding, which is expected to become standardized surgical approach for RPD.

CD133(+) gallbladder carcinoma cells exhibit self-renewal ability and tumorigenicity.

AIM: To identify cancer stem cells (CSCs) in human gallbladder carcinomas (GBCs). METHODS: Primary GBC cells were cultured under serum-free conditions to produce floating spheres. The stem-cell properties of the sphere-forming cells, including self-renewal, differentiation potential, chemoresistance and tumorigenicity, were determined in vitro or in vivo. Cell surface expression of CD133 was investigated in primary tumors and in spheroid cells using flow cytometry. The sphere-colony-formation ability and tumorigenicity of CD133(+) cells were assayed. RESULTS: In vitro culture experiments revealed that floating spheroids were generated from primary GBC cells, and these sphere-forming cells could generate new progeny spheroids in serum-free media. Spheroid cells were differentiated under serum-containing conditions with downregulation of the stem cell markers Oct-4, Nanog, and nestin (P < 0.05). The differentiated cells showed lower spheroid-colony-formation ability than the original spheroid cells (P < 0.05). Spheroid cells were more resistant to chemotherapeutic reagents than the congenetic adherent cells (P < 0.05). Flow cytometry showed enriched CD133(+) population in sphere-forming cells (P < 0.05). CD133(+) cells possessed high colony-formation ability than the CD133(-) population (P < 0.01). CD133(+) cells injected into nude mice revealed higher tumorigenicity than their antigen-negative counterparts (P < 0.05). CONCLUSION: CD133 may be a cell surface marker for CSCs in GBC.

siRNA directed against survivin enhances pancreatic cancer cell gemcitabine chemosensitivity.

Survivin is known to be overexpressed in various human malignancies, including pancreatic cancer, and to cause resistance to radiation and chemotherapy, so the regulation of this molecule could be a new strategy for treating pancreatic cancer. In our study, a short interfering RNA (siRNA) plasmid expression vector against survivin was constructed and transfected into human pancreatic cancer cell lines of Panc-1 and BxPC3. The expression of survivin mRNA and protein among the stable transfected cells and the untransfected cells was detected by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot, respectively. Tumor cell growth in vitro was assessed by trypan blue exclusion. The cell cycle distribution and cell apoptosis were measured by flow cytometry. The cytotoxicity assay was measured by the MTT test. Our results showed that survivin siRNA treatment caused a specific and profound decrease of survivin mRNA and protein that was associated with decreased cell growth, spontaneous apoptosis, and a specific G0/G1 arrest. Furthermore, the suppression of survivin can enhance the chemosensitivity of pancreatic cancer cells to gemcitabine significantly. We suggest that the RNAi against survivin gene strategy would be a potential approach to chemosensitization therapy in human pancreatic cancer.

Proteome analysis of human pancreatic ductal adenocarcinoma tissue using two-dimensional gel electrophoresis and tandem mass spectrometry for identification of disease-related proteins.

A comparative proteomic approach has been used to identify and analyze proteins related to pancreatic cancer. Proteomes of eight pairs of clinical pancreatic ductal adenocarcinoma (PDAC) tissue samples and samples of normal adjacent tissue were obtained by two-dimensional gel electrophoresis (2DE). Comprehensive analysis of proteins was focused on total protein spots for which there were statistical differences between the two groups. Proteins were identified by peptide mass fingerprinting with tandem mass spectrometry (MS-MS). Western blotting and immunohistochemistry (IHC) were also performed to verify the expression of some candidate proteins. Thirty protein spots were identified, including proteases, antioxidant proteins, signal-transduction proteins, calcium-binding proteins, structural proteins, chaperones, and others. Western blotting and IHC confirmed up-regulated expression of two candidate proteins, nucleotide diphosphatase kinase (NDPK) and annexin II, in tumorous tissues. These results suggest that combination of 2DE with MS is an effective strategy for discovery of differently expressed proteins in PDAC which may be molecular markers for diagnosis or therapeutic targets.