Heparin inhibits the inflammatory response induced by LPS and HMGB1 by blocking the binding of HMGB1 to the surface of macrophages.

High mobility group box 1 protein (HMGB1), a nuclear non-histone DNA-binding protein, is secreted extracellularly during inflammation and is a late mediator of inflammatory responses. The pro-inflammatory activity of recombinant HMGB1 proteins is dependent upon the formation of complexes with other mediators, such as lipopolysaccharide (LPS). This study investigated the influence of heparin on LPS+HMGB1-mediated inflammatory responses in cultured macrophages and a murine sepsis model. HMGB1 promoted the phosphorylation of p38 and ERK1/2. HMGB1 enhanced the induction of the pro-inflammatory cytokine, TNF-α, by LPS in macrophages. Heparin blocked the binding of HMGB1 to the surface of macrophages, and suppressed the phosphorylation of p38 and ERK1/2, but not JNK; TNF-α secretion was also decreased. However, heparin alone did not affect LPS-induced production of TNF-α. Heparin reduced lethality in mice exposed to LPS+HMGB1. To conclude, heparin inhibited LPS-induced HMGB1-amplified inflammatory responses by blocking HMGB1 binding to macrophage surfaces. Heparin could be used therapeutically as an effective inhibitor of HMGB1-associated inflammation.

Surgical treatment of chronic pancreatitis in young patients.

The main treatment strategies for chronic pancreatitis in young patients include therapeutic endoscopic retrograde cholangio-pancreatography (ERCP) intervention and surgical intervention. Therapeutic ERCP intervention is performed much more extensively for its minimally invasive nature, but a part of patients are referred to surgery at last. Historical and follow-up data of 21 young patients with chronic pancreatitis undergoing duodenum-preserving total pancreatic head resection were analyzed to evaluate the outcomes of therapeutic ERCP intervention and surgical intervention in this study. The surgical complications of repeated therapeutic ERCP intervention and surgical intervention were 38% and 19% respectively. During the first therapeutic ERCP intervention to surgical intervention, 2 patients developed diabetes, 5 patients developed steatorrhea, and 5 patients developed pancreatic type B pain. During the follow-up of surgical intervention, 1 new case of diabetes occurred, 1 case of steatorrhea recovered, and 4 cases of pancreatic type B pain were completely relieved. In a part of young patients with chronic pancreatitis, surgical intervention was more effective than therapeutic ERCP intervention on delaying the progression of the disease and relieving the symptoms.

[Expression of hypoxia inducible factor-1α and insulin in pancreatic cancer and their correlation].

OBJECTIVE: To explore the correlation between the expressions of hypoxia inducible factor-1α (HIF-1α) and insulin in pancreatic cancer. METHODS: HIF-1α and insulin expression was detected by immunohistochemistry in the center and the edge of pancreatic adenocarcinoma specimens of 65 cases. Western blot was used to detect HIF-1α expression and insulin level in the center and the edge of pancreatic adenocarcinoma specimens of 28 cases. The relationship between HIF-1α expression and insulin level in the pancreatic cancer was analyzed. RESULTS: The results of immunohistochemistry and Western blot showed that HIF-1α protein expression was high in both the center and the edge of pancreatic cancers (P > 0.05), and insulin level was significantly higher at the edge of specimen than that in the center (P < 0.05). HIF-1α protein and insulin levels were positively correlated at the edge of cancer tissue (r = 0.374, P < 0.05), but no significant correlation between them in the center of cancerous tissue (r = -0.145, P > 0.05). CONCLUSION: Insulin may promote the local invasion and metastasis of pancreatic cancer by up-regulating HIF-1α.

Differentiation of CD24- pancreatic ductal cell-derived cells into insulin-secreting cells.

Pancreatic progenitor cells represent both a potential source of transplantable islets for the treatment of diabetes and a valuable instrument for the investigation of the tumorigenesis of pancreatic carcinoma. It has been reported that pancreatic ductal cells of adults have the characteristics of pancreatic progenitors, but whether these cells can generate endocrine cells requires verification. Here, the differentiation of daughter cells of CD24(-) pancreatic ductal cells into insulin-secreting cells in vitro is reported. Crude pancreatic ductal cells were first obtained from adult mice by gradient centrifugation, and then the CD24(-) cells were isolated with a fluorescence-activated cell sorter. The isolated cells were cultured in serum-containing medium at clonal density to form epithelial colonies (ECs). The ECs were then stimulated with basic fibroblast growth factor (bFGF). After 72 h, insulin-secreting cells were observed in the ECs. These results indicate that the daughter cells of CD24(-) pancreatic ductal cells can differentiate into insulin-secreting cells in vitro when stimulated with exogenous bFGF. Therefore, CD24(-) pancreatic ductal cells have the potential to be pancreatic progenitor cells.

Isolation and biological analysis of tumor stem cells from pancreatic adenocarcinoma.

AIM: To explore the method of isolation and biological analysis of tumor stem cells from pancreatic adenocarcinoma cell line PANC-1. METHODS: The PANC-1 cells were cultured in Dulbecco modified eagle medium F12 (1:1 volume) (DMEM-F12) supplemented with 20% fetal bovine serum (FBS). Subpopulation cells with properties of tumor stem cells were isolated from pancreatic adenocarcinoma cell line PANC-1 according to the cell surface markers CD44 and CD24 by flow cytometry. The proliferative capability of these cells in vitro were estimated by 3-[4,5-dimehyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide (MTT) method. And the tumor growth of different subpopulation cells which were injected into the hypodermisof right and left armpit of nude mice was studied, and expression of CD44 and CD24 of the CD44(+)CD24(+) cell-formed nodules and PANC-1 cells were detected by avidin-biotin-peroxidase complex (ABC) immunohistochemical staining. RESULTS: The 5.1%-17.5% of sorted PANC-1 cells expressed the cell surface marker CD44, 57.8% -70.1% expressed CD24, only 2.1%-3.5% of cells were CD44(+) CD24(+). Compared with CD44(-)CD24(-) cells, CD44(+)CD24(+) cells had a lower growth rate in vitro. Implantation of 10(4) CD44(-)CD24(-) cells in nude mice showed no evident tumor growth at wk 12. In contrast, large tumors were found in nude mice implanted with 10(3) CD44(+)CD24(+) cells at wk 4 (2/8), a 20-fold increase in tumorigenic potential (P < 0.05 or P < 0.01). There was no obvious histological difference between the cells of the CD44(+)CD24(+) cell-formed nodules and PANC-1 cells. CONCLUSION: CD44 and CD24 may be used as the cell surface markers for isolation of pancreatic cancer stem cells from pancreatic adenocarcinoma cell line PANC-1. Subpopulation cells CD44(+)CD24(+) have properties of tumor stem cells. Because cancer stem cells are thought to be responsible for tumor initiation and its recurrence after an initial response to chemotherapy, it may be a very promising target for new drug development.

Persistence of side population cells with high drug efflux capacity in pancreatic cancer.

AIM: To investigate the persistence of side population (SP) cells in pancreatic cancer and their role and mechanism in the drug resistance. METHODS: The presentation of side population cells in pancreatic cancer cell line PANC-1 and its proportion change when cultured with Gemcitabine, was detected by Hoechst 33342 staining and FACS analysis. The expression of ABCB1 and ABCG2 was detected by real-time PCR in either SP cells or non-SP cells. RESULTS: SP cells do exist in PANC-1, with a median of 3.3% and a range of 2.1-8.7%. After cultured with Gemcitabine for 3 d, the proportion of SP cells increased significantly (3.8% +/- 1.9%, 10.7% +/- 3.7%, t = 4.616, P = 0.001 < 0.05). ABCB1 and ABCG2 expressed at higher concentrations in SP as compared with non-SP cells (ABCB1: 1.15 +/- 0.72, 5.82 +/- 1.16, t = 10.839, P = 0.000 < 0.05; ABCG2: 1.16 +/- 0.75, 5.48 +/- 0.94, t = 11.305, P = 0.000 < 0.05), which may contribute to the efflux of fluorescent staining and drug resistance. CONCLUSION: SP cells with inherently high resistance to chemotherapeutic agents do exist in pancreatic cancers, which may be candidate cancer stem cells contributing to the relapse of the tumor.

Pancreas duodenal homeobox-1 expression and significance in pancreatic cancer.

AIM: To study the correlations of Pancreas duodenal homeobox-1 with pancreatic cancer characteristics, including pathological grading, TNM grading, tumor metastasis and tumor cell proliferation. METHODS: Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect PDX-1 mRNA expression in pancreatic cancer tissue and normal pancreatic tissue. The expression of PDX-1 protein was measured by Western blot and immunohistochemistry. Immunohistochemistry was also used to detect proliferative cell nuclear antigen (PCNA). Correlations of PDX-1 with pancreatic cancer characteristics, including pathological grading, TNM grading, tumor metastasis and tumor cell proliferation, were analyzed by using c2 test. RESULTS: Immunohistochemistry showed that 41.1% of pancreatic cancers were positive for PDX-1 expression, but normal pancreatic tissue except islets showed no staining for PDX-1. In consistent with the result of imunohistochemistry, Western blot showed that 37.5% of pancreatic cancers were positive for PDX-1. RT-PCR showed that PDX-1 expression was significantly higher in pancreatic cancer tissues than normal pancreatic tissues (2(-3.56 +/- 0.35) vs 2(-8.76 +/- 0.14), P < 0.01). Lymph node metastasis (P < 0.01), TNM grading (P < 0.05), pathological grading (P < 0.05) and tumor cell proliferation (P < 0.01) were significantly correlated with PDX-1 expression levels. CONCLUSION: PDX-1 is re-expressed in pancreatic cancer, and PDX-1-positive pancreatic cancer cells show more malignant potential compared to PDX-1-negative cells. Therefore, PDX-1-positive cells may be tumor stem cells and PDX-1 may act as alternate surface marker of pancreatic cancer stem cells.

In vitro pancreas duodenal homeobox-1 enhances the differentiation of pancreatic ductal epithelial cells into insulin-producing cells.

AIM: To observe whether pancreatic and duodenal homeobox factor-1 enhances the differentiation of pancreatic ductal epithelial cells into insulin-producing cells in vitro. METHODS: Rat pancreatic tissue was submitted to digestion by collegenase, ductal epithelial cells were separated by density gradient centrifugation and then cultured in RPMI1640 medium with 10% fetal bovine serum. After 3-5 passages, the cells were incubated in a six-well plate for 24 h before transfection of recombination plasmid XlHbox8VP16. Lightcycler quantitative real-time RT-PCR was used to detect the expression of PDX-1 and insulin mRNA in pancreatic epithelial cells. The expression of PDX-1 and insulin protein was analyzed by Western blotting. Insulin secretion was detected by radioimmunoassay. Insulin-producing cells were detected by dithizone-staining. RESULTS: XlHbox8 mRNA was expressed in pancreatic ductal epithelial cells. PDX-1 and insulin mRNA as well as PDX-1 and insulin protein were significantly increased in the transfected group. The production and insulin secretion of insulin-producing cells differentiated from pancreatic ductal epithelial cells were higher than those of the untransfected cells in vitro with a significant difference (1.32 +/- 0.43 vs 3.48 +/- 0.81, P < 0.01 at 5.6 mmol/L; 4.86 +/- 1.15 vs 10.25 +/- 1.32, P < 0.01 at 16.7 mmol/L). CONCLUSION: PDX-1 can differentiate rat pancreatic ductal epithelial cells into insulin-producing cells in vitro. In vitro PDX-1 transfection is a valuable strategy for increasing the source of insulin-producing cells.

PDX-1 expression and proliferation of duct epithelial cells after partial pancreatectomy in rats.

BACKGROUND: The pancreas has a strong regeneration potential in mammals. Previous studies suggested that pancreas regeneration is correlated with proliferation and differentiation of pancreatic stem cells, but the field of pancreatic stem cells is still in its infancy. This study was undertaken to detect the expression of pancreas/duodenal homeobox-1 (PDX-1) and proliferation of pancreatic duct epithelial cells in remnant pancreas during regeneration after partial pancreatectomy in rats, and characterize the source of pancreatic stem cells. METHODS: Partial pancreatectomy (90%) was performed on four- to five-week-old Sprague-Dawley rats, and duct epithelial cells and acinar cells were detected by immunohistochemical staining and scored using the 5-bromo-2-deoxyuridine (BrdU) labelling index at various time points. Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to assess the expression of PDX-1 protein and mRNA, respectively. RESULTS: At 24 hours after partial pancreatectomy, proliferation started in the main, large and small duct cells, and persisted in small duct cells to day 5. The experimental and control groups were significantly different (P<0.001). BrdU-positive acinar cells were greatly increased and reached a peak on day 5. PDX-1 protein was only faintly detectable in pancreatic ductal cells on day 1 after partial pancreatectomy. On days 2 and 3, a 2-3 fold increase in PDX-1 protein was observed, corresponding to the characteristic 42 kD protein in Western blotting. The operated and sham-operated groups also differed significantly (P<0.05). PDX-1 protein expression on days 5 and 7 after operation did not differ from that of the control group. RT-PCR revealed that PDX-1 mRNA expression did not significantly differ between the operated group and the sham-operated group at various time points. CONCLUSIONS: Pancreatic stem cells in pancreatic ductal epithelial cells are involved in the regeneration of remnant pancreas and the expression of PDX-1 in ductal cells is due to posttranscriptional regulation.

Implantation of radioactive (125)I seeds improves the prognosis of locally advanced pancreatic cancer patients: A retrospective study.

Locally advanced pancreatic cancer is associated with a very poor prognosis. This study was performed to evaluate whether patients with locally advanced pancreatic cancer benefit from (125)I seed implantation. This retrospective study included 224 patients with locally advanced pancreatic cancer, with 137 patients (61.2%) in the implantation (IP) group and 87 (38.9%) in the non-implantation (NIP) group. The survival status, complications and objective curative effects were compared between the groups. The average operative time in the IP group was significantly longer than that in the NIP group (243±51 vs. 214±77 min). The tumor response rates were 9.5% and 0 at the 2nd month after surgery in the IP and NIP groups, respectively (P<0.05). The IP group exhibited a trend toward pain relief at the 6th month after surgery. The global health status scores of the IP group were higher than those of the NIP group at the 3rd and 6th month after surgery. The median survival time in the IP group was significantly longer than that in the NIP group. In conclusion, patients with locally advanced pancreatic cancer can benefit from (125)I seed implantation in terms of local tumor control, survival time, pain relief and quality of life.

High risk factors of pancreatic carcinoma.

Over the past decades, cancer has become one of the toughest challenges for health professionals. The epidemiologists are increasingly directing their research efforts on various malignant tumor worldwide. Of note, incidence of cancers is on the rise more quickly in developed countries. Indeed, great endeavors have to be made in the control of the life-threatening disease. As we know it, pancreatic cancer (PC) is a malignant disease with the worst prognosis. While little is known about the etiology of the PC and measures to prevent the condition, so far, a number of risk factors have been identified. Genetic factors, pre-malignant lesions, predisposing diseases and exogenous factors have been found to be linked to PC. Genetic susceptibility was observed in 10% of PC cases, including inherited PC syndromes and familial PC. However, in the remaining 90%, their PC might be caused by genetic factors in combination with environmental factors. Nonetheless, the exact mechanism of the two kinds of factors, endogenous and exogenous, working together to cause PC remains poorly understood. The fact that most pancreatic neoplasms are diagnosed at an incurable stage of the disease highlights the need to identify risk factors and to understand their contribution to carcinogenesis. This article reviews the high risk factors contributing to the development of PC, to provide information for clinicians and epidemiologists.

Etiology, pathology, management and prognosis of chronic pancreatitis in Chinese population: A retrospective study.

The purpose of this study was to investigate the etiology, pathological characteristics, management and prognosis of chronic pancreatitis in the Chinese population. The clinical data of 142 patients with chronic pancreatitis were retrospectively studied. All patients were of Chinese nationality and hospitalized from January 2008 to December 2011. Their ages ranged from 14 to 76 years, with a mean of 43 years. Of 142 patients, there were 72 cases of obstructive chronic pancreatitis (50.70%), 19 cases of alcoholic chronic pancreatitis (13.38%), 14 cases of autoimmune pancreatitis (9.86%) and 37 cases of undetermined etiology (26.06%). Pathologically, the average inflammatory mass diameter was 3.8 ± 3.3 cm, biliary obstruction occurred in 36 cases, gall stones in 70 cases, calcification in 88 cases, ductal dilatation in 61 cases, side branch dilatation in 32 cases, ductal irregularity in 10 cases, lymphocytic inflammation in 23 cases, obliterative phlebitis in 14 cases, extra pancreatic lesion in 19 cases and fibrosis in 142 cases. Location of pancreatic lesion in the region of head (n=97), neck (n=16), body (n=12), tail (n=15) and whole pancreas (n=2) influenced the choice of surgical procedures. Ninety-four patients (66.20%) received surgical treatment and 33.80% received other treatments. After operation, 80.85% of 94 patients experienced decreased pain, and 8.51% of 94 showed recovery of endocrine function but with a complication rate of 12.77%. All the operations were performed successfully. According to the pain scale of European Organization for Research and Treatment of Cancer (QLQ-C30) a decrease from 76 ± 22 to 14 ± 18 was observed. Etiology, pathological characteristics, management and prognosis of chronic pancreatitis in the Chinese population vary from others.

Pylorus-preserving versus pylorus-resecting pancreaticoduodenectomy for periampullary and pancreatic carcinoma: a meta-analysis.

BACKGROUND: The aim of this meta-analysis was to compare the long-term survival, mortality, morbidity and the operation-related events in patients with periampullary and pancreatic carcinoma undergoing pylorus-preserving pancreaticoduodenectomy (PPPD) and pylorus-resecting pancreaticoduodenectomy (PRPD). METHOD: A systematic search of literature databases (Cochrane Library, PubMed, EMBASE and Web of Science) was performed to identify studies. Outcome measures comparing PPPD versus PRPD for periampullary and pancreatic carcinoma were long-term survival, mortality, morbidity (overall morbidity, delayed gastric emptying [DGE], pancreatic fistula, wound infection, postoperative bleeding, biliary leakage, ascites and gastroenterostomy leakage) and operation related events (hospital stays, operating time, intraoperative blood loss and red blood cell transfusions). RESULTS: Eight randomized controlled trials (RCTs) including 622 patients were identified and included in the analysis. Among these patients, it revealed no difference in long-term survival between the PPPD and PRPD groups (HR = 0.23, p = 0.11). There was a lower rate of DGE (RR = 2.35, p = 0.04, 95% CI, 1.06-5.21) with PRPD. Mortality, overall morbidity, pancreatic fistula, wound infection, postoperative bleeding, biliary leakage, ascites and gastroenterostomy leakage were not significantly different between the groups. PPPDs were performed more quickly than PRPDs (WMD = 53.25 minutes, p = 0.01, 95% CI, 12.53-93.97); and there was less estimated intraoperative blood loss (WMD = 365.21 ml, p = 0.006, 95% CI, 102.71-627.71) and fewer red blood cell transfusions (WMD = 0.29 U, p = 0.003, 95% CI, 0.10-0.48) in patients undergoing PPPD. The hospital stays showed no significant difference. CONCLUSIONS: PPPD had advantages over PRPD in operating time, intraoperative blood loss and red blood cell transfusions, but had a significantly higher rate of DGE for periampullary and pancreatic carcinoma. PPPD and PRPD had comparable mortality and morbidity including pancreatic fistulas, wound infections, postoperative bleeding, biliary leakage, ascites and gastroenterostomy leakage. Our conclusions were limited by the available data. Further evaluations of high-quality RCTs are needed.

ShRNA silencing glycogen synthase kinase-3 beta inhibits tumor growth and angiogenesis in pancreatic cancer.

Glycogen synthase kinase-3 beta (GSK-3ß), a serine/threonine protein kinase, plays a vital role in the tumorigenesis of many cancers, but its role in pancreatic cancer remains unknown. In this study, we showed that GSK-3ß was aberrantly activated in pancreatic cancer. GSK-3ß knockdown resulted in arrested proliferation and increased apoptosis in pancreatic cancer cell lines. Expression of Bcl-2 and vascular endothelial growth factor (VEGF) decreased significantly in a GSK-3ß knockdown group. In a xenograft tumor model, GSK-3ß knockdown inhibited tumor growth and angiogenesis. Our study showed that GSK-3ß may become a promising therapeutic target for human pancreatic cancer.