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Purpose: Pancreatic cancer is characterized by a dense desmoplasia stroma, which hinders efficient drug delivery and plays a critical role in tumor progression and metastasis. MLN4924 is a first-in-class NEDD8-activating enzyme inhibitor that exhibits anti-tumor activities toward pancreatic cancer, and given the comprehensive effects that MLN4924 could have, we ask what impact MLN4924 would have on the stroma of pancreatic cancer and its underlying mechanisms. Methods: Primary pancreatic stellate cells (PSCs) and human HMEC-1 cells were treated with MLN4924 in vitro. The proliferation and extracellular matrix protein levels of PSCs were tested, and their relationship with transcription factor Gli1 in PSCs was investigated. The angiogenic phenotypes of HMEC-1 cells were evaluated using capillary-like tube formation assay, and their relationship with REDD1 in HMEC-1 cells was investigated. Results: In this study, we found that MLN4924 inhibited the proliferation of pancreatic stellate cells and their secretion of collagen and CXCL-1, and the collagen secretion inhibiting effect of MLN4924 was related with transcription factor Gli1. MLN4924 inhibited multiple angiogenic phenotypes of HMEC-1 cells, and mTOR agonist partially relieved the inhibition of MLN4924 on HEMCs. MLN4924 increased the expression of REDD1 and REDD1 knockdown promoted the angiogenic phenotypes of HMEC-1 cells. Conclusions: Our study suggests that MLN4924 inhibits both the tumor stroma and angiogenesis in pancreatic cancer, and the inhibition effect is related with Gli1 in pancreatic stellate cells and REDD1 in vascular endothelial cells, respectively. [ABSTRACT FROM AUTHOR]

Background: Inflammatory factors and fasting blood glucose were verified to be associated with the prognosis of pancreatic ductal adenocarcinoma. The goal of this study is to confirm the prognostic role of preoperative blood glucose to lymphocyte ratio for patients with resected pancreatic ductal adenocarcinoma. Methods: A total of 259 pancreatic ductal adenocarcinoma patients were enrolled and randomly divided into training cohort and validation cohort. The training cohort was used to generate an optimal cutoff value and the validation cohort was used to further validate the model. Results: A total of 259 patients were incorporated in this study and randomly divided into the training cohort (n = 130, 1/2 of 259) and the validation cohort (129, 1/2 of 259). The optimal cutoff value of glucose to lymphocyte ratio was calculated to be 3.47 for overall survival. Cox regression analysis found that preoperative blood glucose to lymphocyte ratio was independent risk factor (p = 0.040) for overall survival. Prognostic values of glucose to lymphocyte ratio on overall survival were observed in younger male patients with pancreatic body and tail cancer, American Joint Committee on Cancer 8th N1 stage, without microvascular and peripancreatic fat invasion, and Carbohydrate antigen 19–9 higher than 200 U/ml. A prognostic prediction model of overall survival was designed and presented in nomogram. Conclusion: Preoperative blood glucose to lymphocyte ratio is an independent biomarker to predict the overall survival for pancreatic ductal adenocarcinoma patients who underwent curative resection. [ABSTRACT FROM AUTHOR]

TNF receptor-associated factor 6 (TRAF6), a regulator of NF-κB signaling, has been reported to be associated with the oncogenesis of various tumors including pancreatic cancer, but the underlying mechanisms remain unknown. Here, we found that knocking down the expression of TRAF6 impaired YAP signaling. Moreover, TRAF6 promoted the migration and colony formation of pancreatic cancer cells through YAP. Then, we found that TRAF6 interacted with and promoted the ubiquitination and degradation of MST1, and the expression of TRAF6 and MST1 was negatively correlated in primary human pancreatic cancer samples. Our results reveal that TRAF6 regulates YAP signaling by promoting the ubiquitination and degradation of MST1 in pancreatic cancer, suggesting that TRAF6 could be a possible E3 ligase of MST1 and a potential therapeutic target. [ABSTRACT FROM AUTHOR]

The prognosis for pancreatic ductal adenocarcinoma (PDAC) remains extremely poor. Recent studies have focused on the role of lymphocytes in the PDAC microenvironment. Using immunohistochemistry, our study explored the clinical significance of intratumoral or peritumoral CD4Foxp3 regulatory T cells (Tregs) and CD8 T cells in the tumor microenvironment and analyzed their relation to the prognosis of PDAC in a consecutive series of 92 patients after resection. CD8 T cells were more frequently seen within peritumoral sites, while CD4Foxp3 Tregs were more frequent within intratumoral areas. Neither exhibited any relationship with other clinicopathologic factors. Patients with low levels of intratumoral Tregs had longer disease-free survival than those with higher levels (DFS 22.2 vs. 11.2 months, p < 0.001), and patients with higher levels of peritumoral CD8 T cells had longer overall survival than those with lower levels (OS 31.0 vs. 14.2 months, p < 0.001). Multivariate analysis demonstrated that intratumoral Tregs (hazard ratio, HR 3.39, p = 0.010) and peritumoral CD8 T cells (HR 0.10, p < 0.001) are related to DFS and OS, respectively. These results indicate that intratumoral Tregs are a negative predictor of DFS, while peritumoral CD8 T cells are a positive predictor of OS for PDAC patients with pancreatectomy. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effects of DNA-PKcs deficiency on the chemosensitivity of human hepatoma HepG2 cells to cisplatin (CDDP) and 5-fluorouracil (5-Fu), and to explore the underlying molecular mechanism. After transfection with DNA-PKcs siRNA or control siRNA, HepG2 cells were exposed to combination treatment of CDDP and 5-Fu. The cell viability, DNA damage, cell apoptosis, intracellular reactive oxygen species and glutathione (GSH) level, expression of apoptosis related proteins, activity of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway, and nuclear factor- κB (NF- κB) pathways were assessed. The combination of CDDP and 5-Fu had a synergistic cytotoxic effect in HepG2 cells in terms of the cell viability, DNA damage, apoptosis, and oxidative stress level. DNA-PKcs siRNA could sensitize the HepG2 cells to the combined treatment. DNA-PKcs suppression further reduced the Akt phosphorylation level and Bcl-2 expression in HepG2 cells exposed to CDDP and 5-Fu, but enhanced the expression of pro-apoptotic proteins p53 and caspase-3. Moreover, CDDP could inhibit the transcriptional activity of NF- κB through degradation of IkB-α, while 5-Fu alone seemed in some extent increases the NF- κB activity. The combined treatment with CDDP and 5-Fu resulted in significantly decrease of the transcriptional activity of NF- κB, which was further aggravated by DNA-PKcs siRNA treatment. In conclusion, DNA-PKcs suppression had complementary effects in combination with CDDP and 5-Fu treatment in HepG2 cells, which was associated with suppression of NF- κB signaling pathway cascade, activation of caspase-3 and p53, as well as down-regulation of Bcl-2 and GSH. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is one of the most lethal malignancies, with a poor response to chemotherapy and therefore it is important to identify novel therapeutic targets. TNF receptor-associated factor 6 (TRAF6) , a regulator of NF-κB signaling, has been found recently to be involved in tumorigenesis. However, its function in pancreatic cancer remains poorly understood. Here, we found that the expression of TRAF6 was up-regulated in pancreatic cancer tissues. Moreover, over-expression of TRAF6 in pancreatic cancer cells promoted cell proliferation and migration, whereas down-regulation of TRAF6 impaired the tumorigenicity of pancreatic cancer cells in vitro and in vivo. Mechanistically, TRAF6 regulated the expression of multiple genes involved in cell growth, apoptosis and migration. Our results suggested several important roles of TRAF6 in the pathogenesis of pancreatic cancer. TRAF6 might therefore represent a potential therapeutic target. [ABSTRACT FROM AUTHOR]

The prognosis for pancreatic cancer is very poor, and developing new therapeutic strategies for this cancer is needed. Recently, the Warburg effect (aerobic glycolysis) has attracted much attention for its function in the tumorigenesis. Lactate dehydrogenase A (LDHA) executes the final step of aerobic glycolysis and has been reported to be involved in the tumor progression. However, the function of LDHA in pancreatic cancer has not been studied. Here, we found that the expression of LDHA was elevated in the clinical pancreatic cancer samples. Forced expression of LDHA promoted the growth of pancreatic cancer cells, while knocking down the expression of LDHA inhibited cell growth dramatically. Moreover, silencing the expression of LDHA inhibited the tumorigenicity of pancreatic cancer cells in vivo. Mechanistically, knocking down the expression of LDHA activated apoptosis pathway. Taken together, our study revealed the oncogenic role of LDHA in pancreatic cancer and suggested that LDHA might be a potential therapeutic target. [ABSTRACT FROM AUTHOR]

The objectives of this study were to assess the toxicity and immunological response induced by the intra-dermal (i.d.) administration of MUC1-peptide-pulsed dendritic cells (DCs) in advanced pancreatic cancer patients. Patients with recurrent lesions or metastasis after surgery, and immunohistochemistry positive for MUC1 were treated in cohorts that received 3-6 × 10 DCs i.d. for three or four vaccines. Each vaccine was composed of autologus DCs pulsed with MUC1-peptide. Peripheral blood mononuclear cells (PBMCs) that harvested 2 weeks after the second immunization were compared with PBMCs obtained before treatment for immunological response. Serial ELISPOT assays of PBMCs for antitumor reactivity were performed. Three patients received all four vaccines, and four patients received three vaccines. These patients were evaluable for toxicity and immunological monitoring. There were no grade 3 or 4 toxicities associated with the vaccines or major evidence of autoimmunity. Interferon-γ and granzyme B ELISPOT assay reactivity increased significantly in 2 of 7 patients ( P < 0.05). The administration of MUC1-peptide-pulsed DCs is non-toxic and capable of inducing immunological response to tumor antigen MUC1 in advanced pancreatic cancer patients. Additional studies are necessary to improve tumor rejection responses. [ABSTRACT FROM AUTHOR]

The natural history and clinical manifestation of resected intraductal papillary mucinous neoplasm (IPMN) of the pancreas were elucidated, and based on this, a retrospective pancreatic database was reviewed to identify patients with IPMN who were surgically managed in our department from 1999 to June 2006. Pathologic rereview of each case was performed, and the clinico-pathologic features were examined. Student’s T test and χ2 analysis were used to identify factors associated with malignancy. Fifty-one patients were identified. There were 33 males and 18 females. One patient’s pancreas was unresectable, two patients underwent a total pancreatectomy, 42 patients had a pancreatecoduodenectomy and five patients had distal pancreatectomy. Main-duct type carcinoma was identified in 24 patients; branch-duct type in 15 patients, and mixed type in 12 patients. Invasive carcinoma was present in 35 patients. Weight loss and jaundice occurred more commonly in the invasive group. The average serum CA19-9 level was significantly higher in the invasive group (1542μ vs 94.5μ). The average diameter of the pancreatic duct was also wider in the invasive group (8.7 mm vs 4.3 mm). Significant predictors of malignant IPMNs included weight loss, jaundice, a high level of serum CA19-9, a large pancreatic duct and main-duct type carcinoma. [ABSTRACT FROM AUTHOR]