Meiotic nuclear divisions 1 suppresses the proliferation and invasion of pancreatic cancer cells via regulating H2A.X variant histone

Introduction:Among all malignant tumors of the digestive system,pancreatic carcinoma exhibits the highest mortality rate.Currently,prevention and effective treatment are urgent issues that need to be addressed.Methods:The study focused on meiotic nuclear divisions 1(MND1),integrating data from the Gene Expression Profiling Interactive Analysis(GEPIA)database with prognostic survival analysis.Simultaneously,experiments at cellular level were employed to demonstrate the effect of MND1 on the proliferation and migration of PC.The small-molecule inhibitor of MND1 was used to suppress the migration of PC cells by knocking down MND1 using small interfering RNA(siRNA)in Patu-8988 and Panc1 cell lines.Results:The results of Cell Counting Kit-8 indicated that the suppression of MND1 resulted in a decrease in cell proliferation.Wound healing and Transwell assays revealed that MND1 knockdown reduced cell migration and invasion.Flow cytometry revealed that inhibiting MND1 hindered the cell cycle.Furthermore,MND1 could stimulate the proliferation,migration,and invasion of Patu-8988 and Panc1 cells by increasing the expression of MND1.Notably,MND1 had a positive effect on H2AFX expression in PC cells.Elevated MND1 expression suggests the low overall survival rate of individuals diagnosed with PC.Conclusion:These findings suggest that MND1 has the potential to be a gene with the ability to accurately diagnose and treat PC.

Rare ROS1-CENPW gene in pancreatic acinar cell carcinoma and the effect of crizotinib plus AG chemotherapy:A case report

BACKGROUND This is the first report of an ROS1-CENPW fusion gene in pancreatic malignancies.CASE SUMMARY A 77-year-old woman with a pancreatic tumor and multiple liver metastases was admitted to our hospital.Genetic testing revealed the presence of the ROS1-CENPW fusion gene,a rare fusion gene that has not been previously reported in the field of pancreatic cancer.The patient received crizotinib plus AG(albumin paclitaxel plus gemcitabine)chemotherapy.After treatment,the patient’s condition stabilized,and her prognosis was good.CONCLUSION The ROS1-CENPW gene treatment regimen used in this case is an excellent treatment option that provides new hope for patients with advanced pancreatic cancer and similar genetic mutations.To date,owing to the rarity of the ROS1-CENPW fusion gene,our team has encountered only a single case.Therefore,the efficacy of crizotinib plus AG chemotherapy in patients with pancreatic acinar cell carcinoma harboring the ROS1-CENPW fusion gene requires further validation.

Roles of Smad3 and Smad7 in rat pancreatic stellate cells activated by transforming growth factor-beta 1

BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.

Insulin Promotes Proliferative Vitality and Invasive Capability of Pancreatic Cancer Cells via Hypoxia-inducible Factor 1α Pathway

This study examined whether insulin-stimulated hypoxia-inducible factor 1α(HIF-1α) expression plays a crucial role in promoting the proliferative vitality and invasive capability in human pancreatic cancer cells.PANC-1 cells were divided into three groups:Control group,insulin group and insulin+YC-1(a pharmacological inhibitor of HIF-1α) group in terms of different treatments.Cells in the insulin group or insulin+YC-1 group were treated with insulin(0.1,1,10 and 100 nmol/L) alone or combined with 3-(5’-hydroxymethyl-2’-furyl)-1-benzyl indazole(YC-1,0.1,1,10 and 100 μmol/L).HIF-1α mRNA and protein expression in PANC-1 cells was determined by real-time RT-PCR and Western blotting respectively.Cell proliferation and invasion were measured by using growth curve and invasion assay,respectively.Western blot analysis demonstrated that insulin dose-dependently increased the HIF-1α protein expression,and YC-1 could dose-dependently block this effect.However,neither insulin nor YC-1 altered HIF-1α mRNA levels in PANC-1 cells.Moreover,insulin could enhance the proliferation and invasion of PANC-1 cells,while YC-1 could weaken this effect.It was concluded that the malignant proliferation and local invasion of pancreatic cancer cells may be related to high-insulin microenvironment.The tumor biological behavior change resulting from high-insulin microenvironment may be associated with the increased expression of HIF-1α protein.

1-MT Enhances Potency of Tumor Cell Lysate-pulsed Dendritic Cells against Pancreatic Adenocarcinoma by Downregulating the Percentage of Tregs

This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cells(DCs) pulsed with tumor cell lysate in the mice bearing pancreatic adenocarcinoma.The models of pancreatic adenocarcinoma were established in C57BL/6 mice by subcutaneous injection of Pan02 cells.Eight mice which were subcutaneously injected with PBS served as control.The expression of IDO was determined in tumor draining lymph nodes(TDLNs) and spleens of the murine pancreatic adenocarcinoma models.The prevalence of Tregs was measured in the TDLNs and spleens before and after 1-MT administration.The dendritic cells were pulsed with tumor cell lysate for preparing DC vaccine.The DC vaccine,as a single agent or in combination with 1-MT,was administered to pancreatic adenocarcinoma mice.The anti-tumor efficacy was determined after different treatments by regular observation of tumor size.The results showed that the levels of IDO mRNA and protein in tumor-bearing mice were significantly higher than those in the normal control mice.The percentage of Tregs in the spleen and TDLNs was also higer in tumor-bearing mice than in normal control mice(P<0.05).Foxp3 expression was significantly lower in the TDLNs and spleens of tumor-bearing mice administrated with 1-MT than that in normal control mice.Furthemore,in the mice that were administered 1-MT plus DC vaccine,the tumor was increased more slowly than in mice treated with DC vaccine or 1-MT alone,or PBS on day 36(P<0.01).Our results indicated that 1-MT may enhance anti-tumor efficacy of dendritic cells pulsed with tumor cell lysate by downregulating the percentage of Tregs.

Endothelin-1 stimulates contraction and migration of rat pancreatic stellate cells

AIM: To examine the ability of ET-1 to affect the cell functions of PSCs and the underlying molecular mechanisms.METHODS: PSCs were isolated from the pancreas of male Wistar rats after perfusion with collagenase, and cells between passages two and five were used. Expression of ET-1 and ET receptors was assessed by reverse transcription-PCR and immunostaining. Phosphorylation of myosin regulatory light chain (MLC), extracellular-signal regulated kinase (ERK), and Akt was examined by Western blotting. Contraction of PSCs was assessed on hydrated collagen lattices. Cell migration was examined using modified Boyden chambers. Cell proliferation was assessed by measuring the incorporation of 5-bromo-2'-deoxyuridine.RESULTS: Culture-activated PSCs expressed ETA and ETB receptors, and ET-1. ET-1 induced phosphorylation of MLC and ERK, but not Akt. ET-1 induced contraction and migration,but did not alter proliferation of PSCs. ET-1-induced contraction was inhibited by an ETA receptor antagonist BQ-123 and an ETB receptor antagonist BQ-788, whereas migration was inhibited by BQ-788 but not by BQ-123. A Rho kinase inhibitor Y-27632 abolished both contraction and migration.CONCLUSION: ET-1 induced contraction and migration of PSCs through ET receptors and activation of Rho-Rho kinase. ETA and ETB receptors play different roles in the regulation of these cellular functions in response to ET-1.

PDX-1 Expression in Pancreatic Ductal Cells after Partial Pancreatectomy in Adult Rats

To investigate the protein and mRNA expression of pancreas/duodenal homeobox-1 (PDX-1), a transcription factor as a marker for pancreatic stem cells, in pancreatic ductal cells of rats after partial (90 %) pancreatectomy and evaluated the significance of the PDX-1 expression. Western blot and Reverse transcriptase-polymerase chain reaction (RT-PCR) were used to detect the expression of PDX-1 protein and mRNA respectively. PDX-1 protein was only faintly detected in pancreatic ductal cells on the day 1 after partial pancreatectomy. On the day 2 and 3 after operation in operation group, a 2—3 fold increased PDX-1 protein was observed, corresponding to the characteristic 42—kD protein in Western blot. There was significant difference between operation group and sham-operation group (P<0.05). PDX-1 protein expression on the day 5 and 7 after operation had already been no difference from control group (P>0.05). RT-PCR revealed the PDX-1 mRNA expression showed no significant difference between operation group at various time points and sham-operation group (P>0.05). These results indicate that there was overexpression of PDX-1 in the cells of pancreatic epithelium during the regeneration of remnant pancreas after partial pancreatectomy in adult rats, suggesting the 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 was regulated posttranscription.

Molecular determinants of the profibrogenic effects of endothelin-1 in pancreatic stellate cells

AIM: To gain molecular insights into the expression and functions of endothelin-1 (ET-1) in pancreatic stellate cells (PSC). METHODS: PSCs were isolated from rat pancreas tissue, cultured, and stimulated with ET-1 or other extra-cellular mediators. Cell proliferation was assessed by measuring the incorporation of 5-bromo-2'-deoxyuridine into DNA and cell migration was studied in a transwell chamber assay. Gene expression at the level of mRNA was quantified by real-time polymerase chain reaction. Expression and phosphorylation of proteins were monitored by immunoblotting, applying an infrared imaging technology. ET-1 levels in cell culture supernatants were determined by an enzyme immunometric assay. To study DNA binding ofindividual transcription factors, electrophoretic mobility shift assays were performed. RESULTS: Among several mediators tested, transforming growth factor-β1 and tumour necrosis factor-α displayed the strongest stimulatory effects on ET-1 secretion. The cytokines induced binding of Smad3 and NF-κB, respectively, to oligonucleotides derived from the ET-1 promoter, implicating both transcription factors in the induction of ET-1 gene expression. In accordance with previous studies, ET-1 was found to stimulate migration but not proliferation of PSC. Stimulation of ET-1 receptors led to the activation of two distinct mitogen-activated protein kinases, p38 andextracellular signal-regulated kinases (ERK)1/2, as well as the transcription factor activator protein-1. At the mRNA level, enhanced expression of the PSC activation marker, α-smooth muscle actin and two proin· ammatory cytokines, interleukin (IL)-1β and IL-6, was observed. CONCLUSION: This study provides novel lines of evidence for profibrogenic and proin· ammatory actions of ET-1 in the pancreas, encouraging further studies with ET-1 inhibitors in chronic pancreatitis.

Characterization of H^+ and HCO_3^- transporters in CFPAC-1 human pancreatic duct cells

瞄准：在极化的 CFPAC-1 描绘 H+ 和 HCO3- 运输 ers 人的胰腺的管房间，它与 DeltaF508 CFTR 变化从一个膀胱的纤维变性病人被导出。方法：CFPAC-1 房间在高密度被播种到可渗透的支持上并且成长到融合。房间与 pH 敏感的荧光灯的染料 BCECF 被装载，并且增长了进一个灌注房间，它允许 basolateral 和顶端的膜的同时的灌注。Transmembrane 基础流动在细胞内部的 pH 和房间的缓冲能力从变化被计算。结果：我们的结果显示出微分渗透到 HCO3-/CO2 在顶端并且 CFPAC-1 房间的 basolateral 膜。Na+/HCO3- co-transporters (NBC ) 和 Cl-/HCO3- exchangers (AE ) 在两个上在 basolateral 膜，和 Na+/H+ exchangers (NHE ) 上是在场的顶端并且房间的 basolateral 膜。Basolateral HCO3- 举起对细胞外的 K+ 集中的变化敏感，膜可渗透的碳酸酐酶(CA ) 禁止者乙酰唑胺(100 micromol/L ) 和 ethoxyzolamide (100 micromol/L ) ，并且被 H2do (600 micromol/L ) 部分禁止。膜透不过的 CA 禁止者 1-N-(4-sulfamoylphenylethyl )-2,4,6-trimethylpyridine 高氯酸盐没在 HCO3- 举起上有任何效果。basolateral AE 在顶端的膜比那举办了一项高得多的活动，而没有有在放松条件下面的 NHE 的如此的差别。另外， 10 micromol/L forskolin 显著地没影响 Cl-/HCO3- 交换在上顶端并且 basolateral 膜。250 micromol/L H2do 的管理显著地禁止了 basolateral AE。Amiloride (300 micromol/L ) 完全在房间的两膜上禁止了 NHE。RT-PCR 揭示了 pNBC1， AE2，和 NHE1 mRNA 的表示。结论：这些数据建议除了 CFTR 和顶端的 Cl-/HCO3- exchanger 活动的缺乏， CFPAC-1 细胞表示类似的 H+ 和 HCO3- 运输 ers 到在本国的动物织物观察的那些。

Metastatic pancreatic and lung cancer patient in complete remission following immunotherapy: A case report and review of literature

BACKGROUND Metastatic pancreatic ductal adenocarcinoma(PDAC)is a lethal malignancy with dispiriting survival data.Immunotherapy is a promising approach to many cancer types,but achieves poor outcomes in advanced PDAC due to its immunosuppressive tumor microenvironment.We describe a case of metastatic PDAC effectively treated with pembrolizumab.CASE SUMMARY We report the case of a 67-year-old woman with unresectable locally advanced PDAC,treated with gemcitabine plus nab-paclitaxel followed by radiotherapy plus capecitabine.At nine months,pancreatic tumor progression was observed at the level of the hepatic hilum with the appearance of a new pulmonary nodule suggestive of a second primary,confirmed by left lung biopsy.Systemic immunotherapy was then initiated with pembrolizumab,an immune checkpoint inhibitor targeting programmed cell death protein-1 that covers the two tumor types.The patient showed a complete metabolic response that was maintained throughout the treatment.The patient continues to be disease-free at 5.6 years since the start of immunotherapy.CONCLUSION These results suggest that the administration of pembrolizumab after chemoradiotherapy has a beneficial effect in patients with metastatic PDAC.To our knowledge,this is the first reported case of a patient with metastatic PDAC and metastatic lung cancer showing such a long-lasting complete response after pembrolizumab treatment without curative surgery.Further studies are required to determine biomarkers that identify PDAC patients most likely to benefit from this immunotherapy.

Expression of platelet endothelial cell adhesion molecule-1 between pancreatic microcirculation and peripheral circulation in rats with acute edematous pancreatitis

OBJECTIVE: To study the ehanges of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation anti pancreatic microcirculation in rats with acute edematous pancreatitis (AEP). METHODS: The model of AEP was established with 50 Wistar rats, and the changes of PECAM-1 expression on PMNs from the splenic vein and inferior vena cava were determined by flow cytometry. RESULTS: PECAM-I expression on PMNs showed no significant difference between pancreatic microcirculation and peripheral circulation at AEP2h and AEP4h time points. From the AEP4h to the AEP8h time point, PECAM-1 expression in peripheral circulation was up-regulated, but PECAM-1 expression in pancreatic microcirculation was down-regulated. PECAM-1 expression had a significant difference between pancreatic microcirculation and peripheral circulation at the AEP8h time point (P<0.05). CONCLUSION: PECAM-1 expression on PMNs is in a converse way between pancreatic microcirculation and peripheral circulation in AEP.

New insights into pancreatic cancer stem cells

Pancreatic cancer(PC) has been one of the deadliest of all cancers, with almost uniform lethality despite aggressive treatment. Recently, there have been important advances in the molecular, pathological and biological understandingof pancreatic cancer. Even after the emergence of recent new targeted agents and the use of multiple therapeutic combinations, no treatment option is viable in patients with advanced cancer. Developing novel strategies to target progression of PC is of intense interest. A small population of pancreatic cancer stem cells(CSCs) has been found to be resistant to chemotherapy and radiation therapy. CSCs are believed to be responsible for tumor initiation, progression and metastasis. The CSC research has recently achieved much progress in a variety of solid tumors, including pancreatic cancer to some extent. This leads to focus on understanding the role of pancreatic CSCs. The focus on CSCs may offer new targets for prevention and treatment of this deadly cancer. We review the most salient developments in important areas of pancreatic CSCs. Here, we provide a review of current updates and new insights on the role of CSCs in pancreatic tumor progression with special emphasis on Dcl K1 and Lgr5, signaling pathways altered by CSCs, and the role of CSCs in prevention and treatment of PC.

Protective effects of total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja on STZ-stimulated INS-1 cells through regulating of autophagy and apoptosis

OBJECTIVE To explore the protective effects of total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja on STZ-stimulated INS-1 cells through regulating of autophagy and apoptosis.METHODS INS-1cells were cultured in media containing 3n M STZ and different doses of total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja.The proliferation of cells was examined by MTT assay,ROS content were detected by fluorescence enzyme label.The levels of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),hydrogen peroxidase(CAT),malondialdehyde(MDA)were also measured by colorimetry.The activities of caspase-3,9 were also observed by Caspase colorimetric assay kit in each group.The expressions of Bcl-2 m RNA and Bax m RNA were detected by Real time PCR,protein expression of LC3-Ⅱand PARP were detected by Western blotting.RESULTS Compared with the control group,total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja could promote the proliferation of INS-1 cells no matter with STZ or not when its concentration lower than 25μg·m L-1;but when its concentration higher than 100μg·m L-(1use individually)or 50μg·m L-1(combined use),total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja might significantly inhibite the growth of the cells whether STZ existed or not.Total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja(6.25,12.5,25μg·m L-1)might inhibit INS-1cell apoptosis,decrease intra-cellular ROS contents,improve the s upernatant liquid SOD,GSH-PX,CAT activities,decrease MDA level,promote INS-1 cell secreting insulin,decrease the protein expressions of autophagy protein LC3Ⅱand apoptosis regulating protein cleaved PARP protein,up-regulate the anti-apoptotic protein Bcl-2 m RNA expression,down-regulate the pro-apoptotic protein Bax m RNA expression and Bcl-2and Bax,reduce the activity of caspase-9 and caspase-3(P<0.05 or P<0.01).CONCLUSION Total triterpenoids extracts from Cyclocarya paliurus(Batal.)Iljinskaja has good protective effect on STZ-stimulated INS-1cells.It can inhibit STZ injured INS-1 cells to overproduce ROS production,enhance endogenous antioxidant enzymes(GSH-Px,SOD,CAT activities),reduce the expression of autophagy protein LC3Ⅱand apoptosisregulating protein cleaved PARP,up-reglute the antiapoptosis protein Bcl-2 expression,down-regulate the pro-apoptotic protein Bax expression,decrease the caspase-9 and caspase-3 activities,and improve the INS-1cell survival rate,and then play a protective effect on damaged INS-1 cells.

Tetracycline-inducible protein expression in pancreatic cancer cells: Effects of CapG overexpression

AIM: To establish stable tetracycline-inducible pancreatic cancer cell lines. METHODS: Suit-2, MiaPaca-2, and Panc-1 cells were transfected with a second generation reverse tetracycline-controlled transactivator protein (rtTA2S-M2), under the control of either a cytomegalovirus (CMV) or a chicken β-actin promoter, and the resulting clones were characterised.RESULTS: Use of the chicken (β-actin) promoter proved superior for both the production and maintenance of doxycycline-inducible cell lines. The system proved versatile, enabling transient inducible expression of a variety of genes, including GST-P, CYP2E1, S100A6, and the actin capping protein, CapG. To determine the physiological utility of this system in pancreatic cancer cells, stable inducible CapG expressors were established. Overexpressed CapG was localised to the cytoplasm and the nuclear membrane, but was not observed in the nucleus. High CapG levels were associated with enhanced motility, but not with changes to the cell cycle, or cellular proliferation. In CapG-overexpressing cells, the levels and phosphorylation status of other actin-moduating proteins (Cofilin and Ezrin/Radixin) were not altered. However, preliminary analyses suggest that the levels of other cellular proteins, such as ornithine aminotransferase and enolase, are altered upon CapG induction. CONCLUSION: We have generated pancreatic-cancer derived cell lines in which gene expression is fully controllable.

Differences in platelet endothelial cell adhesion molecule-1 expression between peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis

AIM: To investigate the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis (AEP).METHODS: Fifty Wistar rats were randomly divided into control group (n=10) and AEP group (n=40). A model of AEP was established by subcutaneous injection of cerulein 5.5 and 7.5 μg/kg at 0 and 1 h after the beginning of experiment respectively. PECAM-1 expression on PMNs from splenic vein and inferior vena cava was determined by RT-PCR at mRNA level and determined by flow cytometry at protein level.RESULTS: In experimental rats, an increased PECAM-1mRNA expression was seen from 4 to 8 h of AEP in peripheral circulation (0.77±0.25%, 0.76±0.28%, 0.89±0.30%,1.00±0.21% ), while in pancreatic microcirculation,expression decreased from 2 h and reached the lowest level at 6 h of AEP (0.78±0.29%, 0.75±0.26%, 0.62±0.28%,0.66±0.20%). There were significant differences at 8-h time point of AEP between peripheral circulation and pancreatic microcirculation (1.00±0.21% vs0.66±0.20%, P＜0.05).Meanwhile,the difference at protein level was also found.CONCLUSION: A reverse expression of PECAM-1 on PMNs was found between peripheral circulation and pancreatic microcirculation, suggesting that inhibition of PECAM-1expression may improve the pathological change of AEP.

Re-expression of Cell Adhesion Molecule Inhibits Growth and Induces Apoptosis of Human Pancreatic Cancer Cell Line PANC-1

This study examined the expression of cell adhesion molecule 1 （CADM1） in pancreatic cancer and the possible mechanism. The expression of CADM 1 was detected by immunohistochemistry in tissues of pancreatic cancer, pancreatitis, and normal pancreas. The plasmid pcDNA3.1-Hy- gro（＋）/CADM1 was transfected into PANC-1 cells （a pancreatic cancer cell line）. The expression of CADM1 in the transfected cells was determined by RT-PCR and Western blotting. Cell growth was measured by the MTT method and cell apoptosis by flow cytometry. The results showed that CADM1 was weakly expressed in tissues of pancreatic cancer in contrast to its high expression in normal pancreatic and pancreatitis tissues. The expression level of CADM in pancreatic caner was intensely correlated with the differentiation degree, lymph node metastasis and TNM stages. The growth of CADMl-transfected PANC-1 cells was significantly suppressed in vitro by a G1 cell cycle arrest and apoptosis occurrence. It was concluded that re-expression of CADM1 inhibits the growth of pancreatic cancer cells and induces their apoptosis in vitro. As a tumor suppressor gene, CADM1 plays an important role in the occurrence, progression and metastasis of pancreatic cancer.

Resveratrol Attenuates Benzo(a)pyrene-Induced Dysfunctions,Oxidative Stress and Apoptosis in Pancreatic Beta-Cells

Background: Diabetes mellitus is one of the major health problems for people all over the world today. According to international diabetes federation reports, diabetes affects 382 million people worldwide. Environmental pollutants have deleterious effects on glucose metabolism and cause insulin resistance. We aimed to investigate the effects of the environmental pollutants benzo(a)pyrene, and the therapeutic potential of resveratrol. Methods: 20 μM of benzo(a)pyrene was administered after 48 h of resveratrol (80 μM) application for 24 h in INS-1 (832/13) insulinoma cells. The cells were treated with 20 μM benzo(a)pyrene for 24 hours after 48 hours initial preconditions with 10 μM resveratrol. Oxidative stress status, insulin secretion and apoptosis were analyzed by molecular techniques. Results: Though resveratrol increased the antioxidant status which was decreased by benzo(a)pyrene, interestingly, it increased the oxidative status. Resveratrol increased benzo(a)pyrene-depleted reduced glutathione levels to the control level. The mRNA expression levels of beta-cell functions associated with genes insulin-1, insulin-2 and sirtuin-1 were upregulated by resveratrol. Resveratrol treatment elevated the insulin concentration of culture medium, and the mRNA expression of forkhead box protein-1 gene. Resveratrol upregulated benzo(a)pyrene-downregulated p53 gene expression. On the other hand, benzo(a)pyrene-downregulated mRNA expression of B-cell lymphoma-2 was induced by resveratrol treatment. Conclusion: The data showed that resveratrol could reverse the oxidative alterations, functional impairments and the carcinogenetic effects of benzo(a)pyrene in pancreas beta-cells.

Impact of Bisphenol A (BPA) and Free Fatty Acids (FFA) on Th2 Cytokine Secretion from INS-1 Cells

Bisphenol A (BPA) is used in huge amounts for many plastic products and is a hormone (estrogen) disrupting agent. BPA as well as FFAs may be deleterious for the immune system. The aim was to identify Th2 cytokines and some of their signal transduction mechanisms in INS-1 cells, an insulin secreting cell line. Screening using a proteome profile indicated an increase of IL-1, IL-2, IL-4, IL-6, IL-10, IL-13 and IL-17 by BPA. Also FFAs (in combination with LPS) were positive. In detailed quantitative measurements, these results were confirmedly indicating a complex array of pro-and anti-inflammatory potential. The interaction of BPA with 17β-estradiol was non-additive with respect to IL-4 and IL-6 release and additive with respect to FFA interaction indicating same and different mechanisms of action, respecttively. As signal transduction PI3K (Wortmannin-sensitive) and STAT-3/6 (Tofacitinib-sensitive) are involved in various effects, INS-1 cells release several cytokines due to BPA and FFA attack which may be involved in disturbance of glucose homoeostasis and type 1 diabetes.

乌苏酸对人胰腺癌细胞PANC-1增殖和凋亡的影响

目的探讨乌苏酸对人胰腺癌细胞PANC-1增殖、凋亡的影响。方法以1.25,2.5,5,10,25,50μmol/L乌苏酸培养PANC-1细胞24,48,72 h,采用四氮唑盐(MTT)法测定细胞活性。实验分为对照1组(等体积二甲基亚砜)及乌苏酸低、中、高剂量组(5,10,20μmol/L乌苏酸),显微镜下观察细胞形态,采用Western blot法检测磷脂酰肌醇3激酶(PI3K),磷酸化的蛋白激酶B(p-Akt),磷酸化哺乳动物雷帕霉素靶蛋白(p-m TOR),活化半胱氨酸蛋白酶3(Cleaved Caspase-3),B淋巴细胞瘤-2(Bcl-2),Bcl-2关联X蛋白(Bax)的蛋白表达水平,采用细胞集落形成实验观察细胞增殖情况。实验分为对照2组(等体积二甲基亚砜)和乌苏酸组(10μmol/L乌苏酸),采用细胞划痕实验观察细胞培养48,72 h的迁移情况。利用分子对接实验模拟乌苏酸与PI3K和Akt2的相互作用。结果随着乌苏酸浓度的升高,PANC-1细胞活性逐渐减弱,24,48,72 h时的半数抑制浓度(IC50)分别为7.89,6.26,5.06μmol/L。与对照1组比较,乌苏酸各剂量组细胞逐渐失去原有形态,且随着浓度的增加,变形细胞数目随之增加,且细胞边界模糊不清;细胞数量显著减少(P<0.05);乌苏酸各剂量组细胞Cleaved Caspase-3、Bax蛋白的表达水平均显著升高,乌苏酸中、高剂量组细胞Bcl-2蛋白表达水平显著降低,乌苏酸各剂量组细胞p-m TOR,中、高剂量组细胞p-Akt,高剂量组细胞PI3K蛋白表达水平均显著降低(P<0.05)。与对照2组比较,乌苏酸组细胞48 h,72 h的迁移距离缩短。乌苏酸的乌苏烷型三萜类结构可进入PI3K与Akt2中的三磷酸腺苷(ATP)结合位点竞争性结合疏水口袋,从而影响PI3K和Akt2与ATP的结合,抑制其激活。结论乌苏酸可通过抑制PI3K/Akt/m TOR信号通路的激活而抑制PANC-1细胞的增殖,促进其凋亡。