WITHDRAWN: Individualized and pancreatic duct diameter-based strategy for pancreaticoenteric anastomosis during pancreaticoduodenectomy.

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

A preoperative nomogram predicts prognosis of up front resectable patients with pancreatic head cancer and suspected venous invasion.

BACKGROUND: Pancreatic head adenocarcinoma is commonly diagnosed at an advanced stage when adjacent vascular invasion is present. This study aimed to establish a preoperative prognostic nomogram for patients who underwent attempted curative resectional surgery for pancreatic head cancer with suspected peripancreatic venous invasion. METHODS: Data on all consecutive patients were retrospectively collected from 2012 to 2016 at four academic institutions. The demographic and radiological parameters were analyzed using univariate and multivariate Cox regression analyses. The final nomogram was established using the concordance Harrell's C-indices and calibration curves from data obtained in three institutions and validated in the cohort of patients coming from the fourth institution. RESULTS: The nomogram was constructed using data from 178 patients while the validation cohort consisted of 61 patients. Age, length of tumor contact, peripancreatic venous abnormalities and lymph node staging were independent factors of overall survival. The nomogram showed good probabilities of survival on calibration curves. The C-index of the model in predicting overall survival (OS) was 0.824 for the validation cohort. CONCLUSIONS: The nomogram accurately predicted OS in patients with pancreatic head cancer with suspected peripancreatic venous invasion after attempted curative pancreatic resectional surgery.

Pancreaticoduodenectomy for borderline resectable pancreatic head cancer with a modified artery-first approach technique.

BACKGROUND: The treatment of borderline resectable pancreatic head cancer (BRPHC) is still controversial and challenging. The artery-first approaches are described to be the important options for the early determination. Whether these approaches can achieve an increase R0 rate, better bleeding control and increasing long-term survival for BRPHC are still controversial. We compared a previously reported technique, a modified artery-first approach (MAFA), with conventional techniques for the surgical treatment of BRPHC. METHODS: A total of 117 patients with BRPHC undergone pancreaticoduodenectomy (PD) from January 2013 to June 2015 were included. They were divided into an MAFA group (n=78) and a conventional-technique group (n=39). Background characteristics, operative data and complications were compared between the two groups. RESULTS: Mean operation time was significantly shorter in the MAFA group than that in the conventional-technique group (313 vs 384 min; P=0.014); mean volume of intraoperative blood loss was significantly lower in the MAFA group than that in the conventional-technique group (534 vs 756 mL; P=0.043); and mean rate of venous resection was significantly higher in the conventional-technique group than that in the MAFA group (61.5% vs 35.9%; P=0.014). Pathologic data, early mortality and morbidity were not different significantly between the two groups. CONCLUSIONS: MAFA is safe, simple, less time-consuming, less intraoperative blood loss and less venous resection, and therefore, may become a standard surgical approach to PD for BRPHC with the superior mesenteric vein-portal vein involvement but without superior mesenteric artery invasion.

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.

Circulating myeloid-derived suppressor cells in patients with pancreatic cancer.

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) are heterogeneous cell types that suppress T-cell responses in cancer patients and animal models, some MDSC subpopulations are increased in patients with pancreatic cancer. The present study was to investigate a specific subset of MDSCs in patients with pancreatic cancer and the mechanism of MDSCs increase in these patients. METHODS: Myeloid cells from whole blood were collected from 37 patients with pancreatic cancer, 17 with cholangiocarcinoma, and 47 healthy controls. Four pancreatic cancer cell lines were co-cultured with normal peripheral blood mononuclear cells (PBMCs) to test the effect of tumor cells on the conversion of PBMCs to MDSCs. Levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) and arginase activity in the plasma of cancer patients were analyzed by enzyme-linked immunosorbent assay. RESULTS: CD14+/CD11b+/HLA-DR- MDSCs were increased in patients with pancreatic or bile duct cancer compared with those in healthy controls, and this increase was correlated with clinical cancer stage. Pancreatic cancer cell lines induced PBMCs to MDSCs in a dose-dependent manner. GM-CSF and arginase activity levels were significantly increased in the serum of patients with pancreatic cancer. CONCLUSIONS: MDSCs were tumor related: tumor cells induced PBMCs to MDSCs in a dose-dependent manner and circulating CD14+/CD11b+/HLA-DR- MDSCs in pancreatic cancer patients were positively correlated with tumor burden. MDSCs might be useful markers for pancreatic cancer detection and progression.

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.

Quality of life after pancreatic surgery.

BACKGROUND: Pancreatic surgery is challenging owing to the anatomical characteristics of the pancreas. Increasing attention has been paid to changes in quality of life (QOL) after pancreatic surgery. AIM: To summarize and analyze current research results on QOL after pancreatic surgery. METHODS: A systematic search of the literature available on PubMed and EMBASE was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies were identified by screening the references of retrieved articles. Studies on patients' QOL after pancreatic surgery published after January 1, 2012, were included. These included prospective and retrospective studies on patients' QOL after several types of pancreatic surgeries. The results of these primary studies were summarized inductively. RESULTS: A total of 45 articles were included in the study, of which 13 were related to pancreaticoduodenectomy (PD), seven to duodenum-preserving pancreatic head resection (DPPHR), nine to distal pancreatectomy (DP), two to central pancreatectomy (CP), and 14 to total pancreatectomy (TP). Some studies showed that 3-6 months were needed for QOL recovery after PD, whereas others showed that 6-12 months was more accurate. Although TP and PD had similar influences on QOL, patients needed longer to recover to preoperative or baseline levels after TP. The QOL was better after DPPHR than PD. However, the superiority of the QOL between patients who underwent CP and PD remains controversial. The decrease in exocrine and endocrine functions postoperatively was the main factor affecting the QOL. Minimally invasive surgery could improve patients' QOL in the early stages after PD and DP; however, the long-term effect remains unclear. CONCLUSION: The procedure among PD, DP, CP, and TP with a superior postoperative QOL is controversial. The long-term benefits of minimally invasive versus open surgeries remain unclear. Further prospective trials are warranted.

"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.

[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.

Prognostic Value of ALP and LDH in Periampullary Carcinoma Patients Undergoing Surgery.

OBJECTIVE: Conversion of normal cells to cancer cells is often accompanied by abnormal synthesis of serum enzymes. Both alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) have been reported to have prognostic value in a variety of malignancies. The aim of this study was to investigate the effect of preoperative serum ALP and LDH levels on the prognosis of patients with periampullary carcinoma who underwent pancreatoduodenectomy (PD). METHODS: According to the preoperative ALP or LDH values, 856 cancer patients receiving PD treatment from January 2001 to January 2019 were divided into high-ALP group and low-ALP group or high-LDH group and low-LDH group. Statistical analysis was carried out to study the differences between the high-ALP and low-ALP groups or the high-LDH and low-LDH groups. Furthermore, the possibility of preoperative ALP or LDH as prognostic factor of periampullary carcinoma was investigated. RESULTS: In both the high-ALP and the high-LDH groups, the prognosis of patients with periampullary carcinoma who underwent PD was worse than that of the low-ALP and low- LDH group. Even through risk factor analysis, it was found that preoperative ALP and LDH could be independent prognostic factor for patients with periampullary carcinoma who underwent PD. CONCLUSION: Preoperative ALP or LDH is an independent risk factor for periampullary carcinoma.

Impact of Percutaneous Transhepatic Biliary Drainage on Clinical Outcomes of Patients with Malignant Obstructive Jaundice Undergoing Laparoscopic Pancreaticoduodenectomy.

Preoperative biliary drainage may increase the morbidity and mortality of pancreaticoduodenectomy. Studies on percutaneous transhepatic biliary drainage (PTBD) before laparoscopic pancreaticoduodenectomy (LPD), however, are scarce. The aim of this study was to examine the impact of PTBD on clinical outcomes of patients with malignant obstructive jaundice undergoing LPD. Clinical data of 172 patients who had malignant obstructive jaundice and underwent LPD from 2014 to 2017 in our hospital were retrospectively analyzed. Demographics, catheter-related complications, postoperative complications, and oncological outcomes were collected and analyzed. Propensity score matching was performed to minimize selection bias associated with the comparison of data between patients who underwent PTBD and then LPD (PTBD group), and those given LPD alone (LPD group). The results showed that, in the PTBD group relative to the LPD group, the operating time was significantly shortened (250.28±69.95 vs. 278.58±86.51 min, P=0.0196), the intraoperative blood loss was markedly reduced (271.96±403.47 vs. 429.72±482.47 mL, P=0.022), and overall rates of complications (16.33% vs. 36.49%, P=0.0025) including postoperative haemorrhage (2.04% vs. 12.16%, P=0.0072) and delayed gastric emptying (4.08% vs. 13.51%, P=0.0251) were greatly decreased. The propensity score-matched analysis, with 48 patients enrolled in each group, revealed no statistically significant differences in operating duration (262.71±68.64 vs. 280.25±83.52 min, P=0.264), intraoperative blood loss (290.21±407.71 vs. 373.75±422.33 mL, P=0.327) and delayed gastric emptying (4.17% vs. 12.50%, P=0.1396). PTBD group had lower incidences in overall complications (22.92% vs. 39.58%, P=0.0481) and postoperative haemorrhage (2.08% vs. 12.50%, P=0.0497) than LPD group. In conclusion, patients with malignant obstructive jaundice may benefit from PTBD procedure before LPD in terms of perioperative outcomes.

[A new method for integrated radical resection of uncinate process of the pancreas: a report of 306 cases].

OBJECTIVE: To investigate the methods and skills of integrated radical resection of uncinate process of the pancreas for patients with periampullary malignant tumor. METHODS: From March 2005 to March 2010, 306 cases of radical pancreaticoduodenectomy (RPD) of periampullary malignant tumor had been continuously performed. By exchanging superior mesenteric artery and controlling blood stream of pancreatic uncinate process, the integrated radical resection of uncinate process for these patients had been successfully completed. Deal with restitution of alimentary tract by all using Child method. The method of simplify binding pancreaticojejunostomy was carried out to pancreatico-jejunal anastomosis. The cases included 169 male and 137 female with 37 - 79 years old, and the mean age was 58 years. Tumor types included 151 pancreatic head and neck tumors, 48 distal bile duct tumors, 55 ampullary tumors and 52 duodenal papilla tumors. RESULTS: Among the 306 cases with RPD, operation time were 4 - 6 h and the blood loss were 200 - 600 ml with no intraoperative and postoperative bleeding of pancreatic uncinate process site. The incidence rates of postoperative bleeding and mortality were 3.3% and 0.9% respectively. The incidence rates of postoperative pancreatic fistula and biliary fistula incidence were 1.6% and 0.6% respectively. And patients with fistula had well recovered by expectant treatment of ultrasound-guided puncture and drainage. Follow-up to March 2010, there were no patients died from the recurrence of superior mesenteric vascular tumor. CONCLUSIONS: By exchanging superior mesenteric artery and controlling blood stream of pancreatic uncinate process, the integrated radical resection of uncinate process for those patients who have periampullary malignant tumor can be successfully completed. It can reduce the operating bleeding, operating time and the miscut of superior mesenteric vein and(or) superior mesenteric artery, it can avoid postoperative pancreas necrosis off, infection and hemorrhage caused by the pancreas uncinate process residues, and it also theoretically reduces the chance of tumor cells spreading.

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.

[Prevention and cure of the complications after radical pancreatoduodenectomy].

OBJECTIVE: To investigate the causes and the measures of prevention and cure of the dangerous complications (bleeding, pancreatic fistula, biliary fistula and death) after radical pancreatoduodenectomy (RPD) for periampullary malignant tumor. METHODS: The rate and management of dangerous complications of 156 cases with RPD which were continuous performed by Department of Biliary-Pancreatic Surgery, Affiliated Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2006 and June 2008 were analyzed retrospectively, including 97 males and 59 females with 37 - 79 years old, the mean age was 56.9 years old. RESULTS: Among the 156 cases with RPD, four patients had massive hemorrhage of gastrointestinal tract due to stress ulcer, two patients had bleeding in the pancreas-intestinal anastomosis after the operation, the rate of postoperative bleeding was 3.9% (6/156). One patient with massive hemorrhage of gastrointestinal tract due to stress ulcer had severe pulmonary infection and ARDS, and died of respiratory failure finally (the overall mortality rate was 0.7%) after ICU for two months. One patients with bleeding in the pancreas-intestinal anastomosis had pancreatic fistula (the rate of pancreatic fistula was 0.7%) 3 days after the second laparotomy to open the jejunum of the pancreas-intestinal anastomosis and make a transfixion of the bleeding points in the stump. Another patient who had the tumor located in the inferior segment of the bile common duct had biliary fistula 11 days after the operation (the rate of biliary fistula was 0.7%). Two patients with fistula had good recovery by expectant treatment of ultrasound-guided puncture and drainage. CONCLUSIONS: Prompt and effective treatment of the complications of bleeding, pancreatic fistula, biliary fistula could maximally decrease the perioperative death rate.

[The technique of radical pancreaticoduodenectomy for malignant tumor in pancreatic head with pressed superior mesenteric blood vessels or portal vein].

OBJECTIVE: To investigate the technique of radical pancreaticoduodenectomy for malignant tumor in pancreatic head with pressed superior mesenteric blood vessel or portal vein. METHODS: From March 2005 to March 2007, thin slice scan and vessel-reconstruction of 56 patients of malignant tumor in pancreatic head with pressed superior mesenteric blood vessels or portal vein were carried out using multidetector spiral CT to evaluate whether peripheral vessels of pancreatic tumor were invaded and whether the tumor was resectable. During the operation, 3 vascular blocking bands for superior mesenteric vein, portal vein and spleen vein or 4 vascular blocking bands (additional one for inferior mesenteric vein) were preset. Under the cross and traction between superior mesenteric vein and superior mesenteric artery, resected the uncinate process of pancreas thoroughly. Using those methods, radical pancreaticoduodenectomy for 56 patients above-mentioned were successfully accomplished. RESULTS: The accuracy for preoperative judging by using multidetector spiral CT whether the peripheral vessels of pancreatic cancer were invaded and whether the tumor was resectable was 98% and 100% separately. Thirty-seven of 56 patients, whose superior mesenteric blood vessels or portal veins were pressed by the tumor of pancreatic head, were operated using 3 vascular blocking bands and 2 patients using 4 vascular blocking bands, followed by suturing the bleeding points of the superior mesenteric vein with 5-0 vascular suture Proline. One patient's superior mesenteric vein was partially resected and restored. The operations cost 5-8 h each and the blood loss was 200-600 ml. There were no operative or postoperative hemorrhage or pancreatic juice leakage. According to the follow-up up to now, 2 patients died of multiple live tumor metastases 7 and 9 months separately after operation, the other 54 patients were still alive. CONCLUSIONS: Thin slice scan and vessel-reconstruction using multidetector spiral CT can accurately judge whether the blood vessels near the pancreatic tumor were invaded and whether the tumor was resectable, using 3 vascular blocking bands or 4 vascular blocking bands and cross, traction of the superior mesenteric blood vessels, operator can easily accomplish the radical pancreaticoduodenectomy of malignant tumor in pancreatic head with pressed superior mesenteric blood vessels and portal vein, which was not resectable or need combined resection of the blood vessels in the traditional opinion.

Preoperative prediction of peripancreatic vein invasion by pancreatic head cancer.

BACKGROUND: Pancreatic adenocarcinoma is often diagnosed at an advanced stage when adjacent vascular invasion is present. Accurate evaluation of presence of vascular invasion can help guide therapy. The aim of this study was to construct a nomogram for preoperative prediction of peripancreatic vein invasion in patients with pancreatic head cancer. STUDY DESIGN: Data of patients with carcinoma head of pancreas and suspected peripancreatic invasion (n = 247) who underwent pancreatic resection with venous reconstruction between January 2012 and January 2017 at four academic institutions were retrospectively analyzed. Univariate and multivariate analyses were used to identify independent risk factors for vein invasion from among demographic, biological, conditional host-related, and anatomical data. A predictive nomogram was constructed based on the identified independent risk factors. RESULTS: The nomogram was constructed using data from 181 patients while the validation cohort consisted of 66 patients. Length of tumor contact (P = 0.031), circumferential vein involvement (P = 0.048), and venous contour abnormalities (P = 0.001) were independent predictors of venous invasion. The C-index of the model in predicting venous invasion was 0.963 for the external validation cohort. Patients could be assigned into low- (< 50%), intermediate- (50-90%), and high-risk (> 90%) groups based on the nomogram to facilitate personalized management. CONCLUSIONS: Vein invasion by pancreatic head cancer is mainly associated with anatomical factors. The nomogram for prediction of vein invasion was found to be practicable.

Let-7c inhibits cholangiocarcinoma growth but promotes tumor cell invasion and growth at extrahepatic sites.

Cholangiocarcinoma (CCA) is a cancer type with high postoperative relapse rates and poor long-term survival largely due to tumor invasion, distant metastasis, and multidrug resistance. Deregulated microRNAs (miRNAs) are implicated in several cancer types including CCA. The specific roles of the miRNA let-7c in cholangiocarcinoma are not known and need to be further elucidated. In our translational study we show that microRNA let-7c expression was significantly downregulated in human cholangiocarcinoma tissues when compared to adjacent tissues of the same patient. Let-7c inhibited the tumorigenic properties of cholangiocarcinoma cells including their self-renewal capacity and sphere formation in vitro and subcutaneous cancer cell growth in vivo. Ectopic let-7c overexpression suppressed migration and invasion capacities of cholangiocarcinoma cell lines in vitro, however, promoted distant invasiveness in vivo. Furthermore, we found that let-7c regulated the aforementioned malignant biological properties, at least in part, through regulation of EZH2 protein expression and through the DVL3/ß-catenin axis. The miRNA let-7c thus plays an important dual role in regulating tumorigenic and metastatic abilities of human cholangiocarcinoma through mechanisms involving EZH2 protein and the DVL3/ß-catenin axis.

A Five-microRNA Signature for Survival Prognosis in Pancreatic Adenocarcinoma based on TCGA Data.

Novel biomarkers for pancreatic adenocarcinoma are urgently needed because of its poor prognosis. Here, by using The Cancer Genome Atlas (TCGA) RNA-seq data, we evaluated the prognostic values of the differentially expressed miRNAs and constructed a five-miRNA signature that could effectively predict patient overall survival (OS). The Kaplan-Meier overall survival curves of two groups based on the five miRNAs were notably different, showing overall survival in 10.2% and 47.8% at five years for patients in high-risk and low-risk groups, respectively. The ROC curve analysis achieved AUC of 0.775, showing good sensitivity and specificity of the five-miRNA signature model in predicting pancreatic adenocarcinoma patient survival risk. The functional enrichment analysis suggested that the target genes of the miRNA signature may be involved in various pathways related to cancer, including PI3K-Akt, TGF-ß, and pluripotent stem cell signaling pathways. Finally, we analyzed expression of the five specific miRNAs in the miRNA signature, and validated the reliability of the results in 20 newly diagnosed pancreatic adenocarcinoma patients using qRT-PCR. The expression results of qRT-PCR were consistent with the TCGA results. Taken together, these findings suggested that the five-miRNA signature (hsa-miR-203, hsa-miR-424, hsa-miR-1266 hsa-miR-1293, and hsa-miR-4772) could be used as a prognostic marker for pancreatic adenocarcinoma.

Gene transfer of somatostatin receptor type 2 by intratumoral injection inhibits established pancreatic carcinoma xenografts.

AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-1 was inoculated subcutaneously into the back of nude mice. When tumor nodules were grown as large as about 5 mmX5 mm days after inoculation, the mice were randomly divided into 3 groups (6 mice in each group). Group I served as untreated control group. Group II received an intratumoral injection of a combination of human cytomegalovirus promoter-6C (pCMV-6C) and lipofectamine 2000. Group III received an intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000. The rate of tumor growth was compared among these three groups. The expression of SSTR2 in these tumors was detected by immunohistochemistry and Western-blot. Apoptosis index (AI) in these tumors was examined by using TUNEL in situ. RESULTS: Intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000 resulted in the expression of SSTR2 protein. The tumor size and weight in group III (0.318+/-0.098 cm3, and 0.523+/-0.090 g, respectively) were significantly lower than those in group I (2.058+/-0.176 cm3, and 1.412+/-0.146 g, respectively) and group II (2.025+/-0.163 cm3, and 1.365+/-0.116 g, respectively) (P<0.05) The AI in group III (1.47+/-0.13%) was significantly higher than that in group I (0.56+/-0.09%) and group II (0.57+/-0.11%) (P<0.05). But there were no significant differences between groups I and II. CONCLUSION: Our data demonstrate that re-expression of SSTR2 gene has antitumor effects on experimental pancreatic cancer. Restoration of SSTR2 gene expression through gene transfer in vivo might be a potential gene therapy strategy for human pancreatic cancer.

Reversal of the phenotype by K-rasval12 silencing mediated by adenovirus-delivered siRNA in human pancreatic cancer cell line Panc-1.

AIM: To investigate the in vitro antitumor effect of adenovirus-mediated small interfering RNAs (siRNAs) on pancreatic cancer and the associated mechanism. METHODS: A 63-nucleotide (nt) oligonucleotide encoding K-ras(val12) and specific siRNA were introduced into pSilencer 3.1-H1, then the H1-RNA promoter and siRNA coding insert were subcloned into pAdTrack to get plasmid pAdTrackH1-K-ras(val12). After homologous recombination in bacteria and transfections of such plasmids into a mammalian packaging cell line 293, siRNA expressing adenovirus AdH1-K-ras(val12) was obtained. Stable suppression of K-ras(val12) was detected by Northern blot and Western blot. Apoptosis in Panc-1 cells was detected by flow cytometry. RESULTS: We obtained adenovirus AdH1-K-ras(val12) carrying the pSilencer 3.1-H1 cassette, which could mediate gene silencing. Through siRNA targeted K-ras(val12), the oncogenic phenotype of cancer cells was reversed. Flow cytometry showed that apoptotic index of Panc-1 cells was significantly higher in the AdH1-K-ras(val12)-treatment group (18.70% at 72 h post-infection, 49.55% at 96 h post-infection) compared to the control groups (3.47%, 3.98% at 72 and 96 h post-infection of AdH1-empty, respectively; 4.21%, 3.78% at 72 and 96 h post-infection of AdH1-p53, respectively) (P<0.05). CONCLUSION: These results demonstrate that adenoviral vectors can be used to mediate RNA interference (RNAi) to induce persistent loss of functional phenotypes. In gene therapy, the selective down-regulation of only the mutant version of a gene allows for highly specific effects on tumor cells, while leaving the normal cells untouched. In addition, the apoptosis of pancreatic cancer cell line Panc-1 can be induced after AdH1-K-ras(val12) infection. This kind of adenovirus based on RNAi might be a promising vector for cancer therapy.