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.

Thymoquinone affects hypoxia-inducible factor-1αexpression in pancreatic cancer cells via HSP90 and PI3K/AKT/mTOR pathways

BACKGROUND Pancreatic cancer(PC)is associated with some of the worst prognoses of all major cancers.Thymoquinone(TQ)has a long history in traditional medical practice and is known for its anti-cancer,anti-inflammatory,anti-fibrosis and antioxidant pharmacological activities.Recent studies on hypoxia-inducible factor-1α(HIF-1α)and PC have shown that HIF-1αaffects the occurrence and development of PC in many aspects.In addition,TQ could inhibit the development of renal cancer by decreasing the expression of HIF-1α.Therefore,we speculate whether TQ affects HIF-1αexpression in PC cells and explore the mechanism.AIM To elucidate the effect of TQ in PC cells and the regulatory mechanism of HIF-1αexpression.METHODS Cell counting kit-8 assay,Transwell assay and flow cytometry were performed to detect the effects of TQ on the proliferative activity,migration and invasion ability and apoptosis of PANC-1 cells and normal pancreatic duct epithelial(hTERTHPNE)cells.Quantitative real-time polymerase chain reaction and western blot assay were performed to detect the expression of HIF-1αmRNA and protein in PC cells.The effects of TQ on the HIF-1αprotein initial expression pathway and ubiquitination degradation in PANC-1 cells were examined by western blot assay and co-immunoprecipitation.RESULTS TQ significantly inhibited proliferative activity,migration,and invasion ability and promoted apoptosis of PANC-1 cells;however,no significant effects on hTERT-HPNE cells were observed.TQ significantly reduced the mRNA and protein expression levels of HIF-1αin PANC-1,AsPC-1,and BxPC-3 cells.TQ significantly inhibited the expression of the HIF-1αinitial expression pathway(PI3K/AKT/mTOR)related proteins,and promoted the ubiquitination degradation of the HIF-1αprotein in PANC-1 cells.TQ had no effect on the hydroxylation and von Hippel Lindau protein mediated ubiquitination degradation of the HIF-1αprotein but affected the stability of the HIF-1αprotein by inhibiting the interaction between HIF-1αand HSP90,thus promoting its ubiquitination degradation.CONCLUSION The regulatory mechanism of TQ on HIF-1αprotein expression in PC cells was mainly to promote the ubiquitination degradation of the HIF-1αprotein by inhibiting the interaction between HIF-1αand HSP90;Secondly,TQ reduced the initial expression of HIF-1αprotein by inhibiting the PI3K/AKT/mTOR pathway.

Programmed cell death 1 inhibitor sintilimab plus concurrent chemoradiotherapy for locally advanced pancreatic adenocarcinoma

BACKGROUND Pancreatic adenocarcinoma,a malignancy that arises in the cells of the pancreas,is a devastating disease with unclear etiology and often poor prognosis.Locally advanced pancreatic cancer,a stage where the tumor has grown significantly but has not yet spread to distant organs,presents unique challenges in treatment.This article aims to discuss the current strategies,challenges,and future directions in the management of locally advanced pancreatic adenocarcinoma(LAPC).AIM To investigate the feasibility and efficacy of programmed cell death 1(PD-1)inhibitor sintilimab plus concurrent chemoradiotherapy for LAPC.METHODS Eligible patients had LAPC,an Eastern cooperative oncology group performance status of 0 or 1,adequate organ and marrow functions,and no prior anticancer therapy.In the observation group,participants received intravenous sintilimab 200 mg once every 3 wk,and received concurrent chemoradiotherapy(concurrent conventional fractionated radiotherapy with doses planning target volume 50.4 Gy and gross tumor volume 60 Gy in 28 fractions and oral S-140 mg/m2 twice daily on days 1-14 of a 21-d cycle and intravenous gemcitabine 1000 mg/m2 on days 1 and 8 of a 21-d cycle for eight cycles until disease progression,death,or unacceptable toxicity).In the control group,participants only received concurrent chemoradiotherapy.From April 2020 to November 2021,64 participants were finally enrolled with 34 in the observation group and 30 in the control group.RESULTS Thirty-four patients completed the scheduled course of chemoradiotherapy,while 32(94.1%)received sintilimab plus concurrent chemoradiotherapy with 2 patients discontinuing sintilimab in the observation group.Thirty patients completed the scheduled course of chemoradiotherapy in the control group.Based on the Response Evaluation Criteria in Solid Tumors guidelines,the analysis of the observation group revealed that a partial response was observed in 11 patients(32.4%),stable disease was evident in 19 patients(55.9%),and 4 patients(11.8%)experienced progressive disease;a partial response was observed in 6(20.0%)patients,stable disease in 18(60%),and progressive disease in 6(20%)in the control group.The major toxic effects were leukopenia and nausea.The incidence of severe adverse events(AEs)(grade 3 or 4)was 26.5%(9/34)in the observation group and 23.3%(7/30)in the control group.There were no treatment-related deaths.The observation group demonstrated a significantly longer median overall survival(22.1 mo compared to 15.8 mo)(P<0.05)and progression-free survival(12.2 mo vs 10.1 mo)(P<0.05)in comparison to the control group.The occurrence of severe AEs did not exhibit a statistically significant difference between the observation group and the control group(P>0.05).CONCLUSION Sintilimab plus concurrent chemoradiotherapy was effective and safe for LAPC patients,and warrants further investigation.

Diabetes mellitus in patients with type 1 autoimmune pancreatitis at diagnosis and after corticosteroid therapy

Background:A high prevalence of diabetes mellitus(DM)coexisting with autoimmune pancreatitis(AIP)is observed.However,evidence on the circumstances under which corticosteroid therapy(CST)for AIP improves or worsens DM is scarce.This study aimed to demonstrate and identify predictors of DM control under the influence of CST.Methods:Patients diagnosed with type 1 AIP were enrolled from a prospectively maintained cohort and were classified into three groups according to the chronology in which AIP and DM were diagnosed:pre-existing DM(pDM),concurrent DM(cDM),and non-DM(nDM).The responses of DM to CST were assessed when corticosteroid was ceased or tapered to a maintenance dose and classified as‘improvement’and‘non-improvement’(including‘no change’and‘exacerbation’).Results:Among 101 patients with type 1 AIP,52(51.5%)patients were complicated with DM at the time of AIP diagnosis,with 36 patients in the cDM group and 16 patients in the pDM group.The incidences of diffuse pancreatic swelling(72.2%)and pancreatic body/tail involvement(91.7%)were significantly higher in the cDM group than in both the pDM and nDM groups.Of the 52 patients with DM,CST was administered in 48 cases.Multivariate logistic analysis identified that elevated serum gamma-glutamyl transferase(GGT)level at AIP diagnosis[odds ratio(OR)=0.032,95%confidence interval(CI):0.003-0.412,P=0.008]and pancreatic atrophy after CST(OR=0.027,95%CI:0.003-0.295,P=0.003)were negatively associated with DM control improvement.Conclusions:Patients with diffuse pancreatic swelling and pancreatic body/tail involvement in pancreatitis tended to be complicated with cDM at AIP diagnosis.CST exerted a beneficial effect on the clinical course of DM in nearly half of the AIP patients complicated with DM at diagnosis,particularly in those without elevated serum GGT levels at diagnosis and who did not experience pancreatic atrophy after CST.

Targeting KRAS in pancreatic cancer

Pancreatic cancer has a dismal prognosis due to late detection and lack of efficient therapies.The Kirsten rat sarcoma virus(KRAS)oncogene is mutated in up to 90%of all pancreatic ductal adenocarcinomas(PDACs)and constitutes an attractive target for therapy.However,the most common KRAS mutations in PDAC are G12D(44%),G12V(34%)and G12R(20%)that are not amenable to treatment by KRAS G12C-directed cysteine-reactive KRAS inhibitors such as Sotorasib and Adagrasib that exhibit clinical efficacy in lung cancer.KRAS G12C mutant pancreatic cancer has been treated with Sotorasib but this mutation is detected only in 2%–3%of PDAC.Recently,the KRAS G12D-directed MRTX1133 inhibitor has entered clinical trials and more of such inhibitors are in development.The other KRAS mutations may be targeted indirectly via inhibition of the cognate guanosine exchange factor(GEF)Son of Sevenless 1 that drives KRAS.These agents seem to provide the means to target the most frequent KRAS mutations in PDAC and to improve patient outcomes.

Mannogalactoglucan from mushrooms protects pancreatic islets via restoring UPR and promotes insulin secretion in TIDM mice

Type 1 diabetes mellitus(T1DM) lacks insulin secretion due to autoimmune deficiency of pancreaticβ-cells.Protecting pancreatic islets and enhancing insulin secretion has been therapeutic approaches.Mannogalactoglucan is the main type of polysaccharide from natural mushroom,which has potential medicinal prospects.Nevertheless,the antidiabetic property of mannogalactoglucan in T1DM has not been fully elucidated.In this study,we obtained the neutral fraction of alkali-soluble Armillaria mellea polysaccharide(AAMP-N) with the structure of mannogalactoglucan from the fruiting body of A.mellea and investigated the potential therapeutic value of AAMP-N in T1DM.We demonstrated that AAMP-N lowered blood glucose and improved diabetes symptoms in T1DM mice.AAMP-N activated unfolded protein response(UPR) signaling pathway to maintain ER protein folding homeostasis and promote insulin secretion in vivo.Besides that,AAMP-N promoted insulin synthesis via upregulating the expression of transcription factors,increased Ca^(2+) signals to stimulate intracellular insulin secretory vesicle transport via activating calcium/calmodulin-dependent kinase Ⅱ(CamkⅡ) and cAMP/PKA signals,and enhanced insulin secretory vesicle fusion with the plasma membrane via vesicle-associated membrane protein 2(VAMP2).Collectively,these studies demonstrated that the therapeutic potential of AAMP-N on pancreatic islets function,indicating that mannogalactoglucan could be natural nutraceutical used for the treatment of T1DM.

Impacts of different pancreatic resection ranges on endocrine function in Suncus murinus

BACKGROUND Surgical intervention involving the pancreas can lead to impaired glucose tolerance and other types of endocrine dysfunction.The scope of pancreatectomy and whether it includes the ventral pancreas are the key factors in the development of postoperative diabetes.The ventral and dorsal pancreases are almost separated in Suncus murinus(S.murinus).AIM To investigate the effects of different extents of pancreatic resection on endocrine function in S.murinus.METHODS Eight-week-old male S.murinus shrews were randomly divided into three experimental groups according to different pancreatic resection ranges as follows:ventral pancreatectomy(VPx)group;partial pancreatectomy(PPx)group;subtotal pancreatectomy(SPx)group;and a sham-operated group.Postprandial serum insulin,glucagon-like peptide-1(GLP-1),pancreatic polypeptide(PP),and somatostatin(SST)levels,as well as food intake,weight,blood glucose,and glucose tolerance were regularly measured for each animal.RESULTS S.murinus treated with PPx and SPx suffered from varying degrees of impaired glucose tolerance,but only a small proportion of the SPx group developed diabetes.Only S.murinus in the SPx group showed a significant decrease in food intake accompanied by severe weight loss,as well as a significant increase in postprandial serum GLP-1 levels.Postprandial serum PP levels decreased in both the VPx and PPx groups,but not in the SPx group.Postprandial serum SST levels decreased in both VPx and PPx groups,but the decrease was marginal.CONCLUSION Severe weight loss after pancreatectomy may be related to loss of appetite caused by compensatory elevation of GLP-1.PP and GLP-1 may play a role in resisting blood glucose imbalance.

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.

Columbianetin acetate inhibits the occurrence and development of pancreatic cancer cells by down-regulating the expression of Meiotic nuclear divisions 1

Columbianetin acetate(CE)is one of the effective components of Angelica pubescens.So far,the specific role and molecular mechanism of CE in pancreatic cancer are not clear.Thus,this study aimed to explore the specific mechanism of CE on pancreatic cancer.The target genes combined with CE were predicted through the PharmMapper database and the 3D molecular structure of CE.Then,the Cancer Genome Atlas(TCGA)and Cistrome data browser(DB)databases were used to screen Meiotic nuclear divisions 1(MND1)-related genes,transcription factors,and transcription factor data sets,and the intersection of the above data sets.The“limma”package in the R and gene expression profiling interactive analysis(GEPIA)databases were used to analyze the correlation and survival difference between the target genes and MND1 to predict the degree of association between CE and MND1.Western blotting and RT-PCR experiments revealed the regulatory relationship among CE,E2F1,and MND1 at the cellular level.The specific effects of CE on pancreatic cancer cells were explored through CCK8,wound healing,migration,and flow cycle experiments.E2F1,also the predictive transcription factor of MND1,was also the predictive target protein of CE.At the same time,E2F1 and MND1 were closely related in pancreatic tissue.In the cell function experiment,CE and interference with E2F1 expression could reduce the gene and protein expression of MND1,which was closely associated with cell proliferation,migration,and cycle development.Similarly,interfering with the expression of mnd1 can also inhibit the further development of tumor cells.CE may inhibit the development of pancreatic cancer cells by reducing the expression of MND1.This implies that CE may be a potential novel agent for the treatment of pancreatic cancer.

Nuclear PLD1 combined with NPM1 induces gemcitabine resistance through tumorigenic IL7R in pancreatic adenocarcinoma

Objective:Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant gastrointestinal cancer with a 5-year survival rate of only 9%.Of PDAC patients,15%-20%are eligible for radical surgery.Gemcitabine is an important chemotherapeutic agent for patients with PDAC;however,the efficacy of gemcitabine is limited due to resistance.Therefore,reducing gemcitabine resistance is essential for improving survival of patients with PDAC.Identifying the key target that determines gemcitabine resistance in PDAC and reversing gemcitabine resistance using target inhibitors in combination with gemcitabine are crucial steps in the quest to improve survival prognosis in patients with PDAC.Methods:We constructed a human genome-wide CRISPRa/dCas 9 overexpression library in PDAC cell lines to screen key targets of drug resistance based on sgRNA abundance and enrichment.Then,co-IP,ChIP,ChIP-seq,transcriptome sequencing,and qPCR were used to determine the specific mechanism by which phospholipase D1(PLD1)confers resistance to gemcitabine.Results:PLD1 combines with nucleophosmin 1(NPM1)and triggers NPM1 nuclear translocation,where NPM1 acts as a transcription factor to upregulate interleukin 7 receptor(IL7R)expression.Upon interleukin 7(IL-7)binding,IL7R activates the JAK1/STAT5 signaling pathway to increase the expression of the anti-apoptotic protein,BCL-2,and induce gemcitabine resistance.The PLD1 inhibitor,Vu0155069,targets PLD1 to induce apoptosis in gemcitabine-resistant PDAC cells.Conclusions:PLD1 is an enzyme that has a critical role in PDAC-associated gemcitabine resistance through a non-enzymatic interaction with NPM1,further promoting the downstream JAK1/STAT5/Bcl-2 pathway.Inhibiting any of the participants of this pathway can increase gemcitabine sensitivity.

Efficacy and safety of gemcitabine plus S-1 vs. gemcitabine plus nab-paclitaxel in treatment-na?ve advanced pancreatic ductal adenocarcinoma

Objective:Gemcitabine plus nab-paclitaxel(GnP)is the standard first-line therapy for advanced pancreatic ductal adenocarcinoma(PDAC).S-1,an oral fluoropyrimidine derivative,as compared with gemcitabine,is non-inferior in terms of overall survival(OS)and is associated with lower hematologic toxicity.Accordingly,S-1 is a convenient oral alternative treatment for advanced PDAC.This study was aimed at comparing the efficacy and safety of gemcitabine plus S-1(GS)vs.GnP as first-line chemotherapy for advanced PDAC.Methods:Patients with advanced PDAC who received first-line GS or GnP at the Peking Union Medical College Hospital between March 2011 and November 2022 were evaluated.Results:A total of 300 patients were assessed,of whom 84 received GS and 216 received GnP.The chemotherapy completion rate was higher with GS than GnP(50.0%vs.30.3%,P=0.0028).The objective response rate(ORR)was slightly higher(14.3%vs.9.7%,P=0.35),and the median OS was significantly longer(17.9 months vs.13.3 months,P=0.0078),in the GS group than the GnP group.However,the median progression-free survival(PFS)did not significantly differ between groups.Leukopenia risk was significantly lower in the GS group than the GnP group(14.9%vs.28.1%,P=0.049).Conclusions:As first-line chemotherapy for advanced PDAC,the GS regimen led to a significantly longer OS than the GnP regimen.The PFS,ORR,and incidence of severe adverse events were comparable between the GS and GnP groups.

Apolipoprotein E2 inhibits mitochondrial apoptosis in pancreatic cancer cells through ERK1/2/CREB/BCL-2 signaling

Background: Apolipoprotein E2(ApoE2) is a pleiotropic protein that influences several aspects of cancer metabolism and development. Evading apoptosis is a vital factor for facilitating cancer cell growth. However, the role and mechanism of ApoE2 in regulating cell apoptosis of pancreatic cancer remain unclear. Methods: In this study, we firstly detected the m RNA and protein expressions of ApoE2 in PANC-1 and Capan-2 cells by real-time polymerase chain reaction and Western blotting. We then performed TUNEL and flow cytometric analyses to explore the role of recombinant human ApoE2, p CMV6-ApoE2 and si ApoE2 in the apoptosis of PANC-1 and Capan-2 cells. Furthermore, we investigated the molecular mechanism through which ApoE2 affected apoptosis in PANC-1 cells using immunofluorescence, immunoprecipitation, Western blotting and co-immunoprecipitation analysis. Results: ApoE2 phosphorylated ERK1/2 and inhibited pancreatic cancer cell apoptosis. In addition, our data showed that ApoE2/ERK1/2 altered the expression and mitochondrial localization of BCL-2 via activating CREB. ApoE2/ERK1/2/CREB also increased the total BCL-2/BAX ratio, inhibited the opening of the mitochondrial permeability transition pore and the depolarization of mitochondrial transmembrane potential, blocked the leakage of cytochrome-c and the formation of the apoptosome, and consequently, suppressed mitochondrial apoptosis. Conclusions: ApoE2 regulates the mitochondrial localization and expression of BCL-2 through the activation of the ERK1/2/CREB signaling cascade to evade the mitochondrial apoptosis of pancreatic cancer cells. ApoE2 may be a distinct prognostic marker and a potential therapeutic target for pancreatic cancer.

The effect of miR-129-5p in pancreatic cancer cells on apoptosis through targeted of HMGB1

Objective:To investigate the role of miR-129-5p in regulating HMGB1 expression in pancreatic cancer cell apoptosis.Methods:The untreated pancreatic cancer SW1990 cells were used as the control group.Mimics-NC(empty vector),miR-129-5p mimics,inhibitor-NC(empty vector)and miR-129-5p inhibitor were transfected into SW1990 cells by liposome transfection method as the mimics-NC group,miR-129-5p overexpression group(miR-129-5p mimics group),inhibitor-NC group and miR-129-5p low expression group(miR-129-5p inhibitor group).The binding site of miR-129-5p and HMGB1 was predicted by online target gene prediction website Target genes,and the targeting relationship between miR-129-5p and HMGB1 was verified by dual luciferase gene report experiment.The expression of miR-129-5p in each group was detected by qRT-PCR,and the expression of HMGB1 protein and apoptosis-related proteins Caspase 3 and Bcl-2 by Western blot.Hoechst staining was used to observe the changes of apoptosis.Results:Compared with the mimics-NC group and control group,miR-129-5p mimics transfection significantly up-regulated miR-129-5p level(P<0.01),inhibited HMGB1(P<0.01)and Bcl-2(P<0.05)protein expression,pro-moted Caspase 3 protein expression(P<0.05),and promoted apoptosis;compared with the inhibitor-NC group and control group,miR-129-5p inhibitor transfection significantly down-regulated miR-129-5p level(P<0.05),promoted HMGB1 and Bcl-2 protein expression(all P<0.05),inhibited Caspase 3protein expression(P<0.01),and inhibited apoptosis.The results of dual luciferase reporter gene assay showed that miR-129-5p could inhibit the fluorescence activity of wildtype HMGB1 cells and target the expression of HMGB1.Conclusion:miR-129-5p promotes the apoptosis of pancreatic cancer SW1990 cells by targeting inhibition of HMGB1 expression.

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.

Positive Correlation between PMS2 Deficiency and PD-L1 Expression in Pancreatic Cancer

Background: Pancreatic cancer is one of the most lethal types of cancer, and immunotherapy has become a promising remedy with advancements in tumor immunology. However, predicting the clinical response to immunotherapy in pancreatic cancer remains a dilemma for clinicians. Methods: GEPIA database was used to analyze the differential expression of MMR and PD-L1 genes in 33 common cancer types including pancreatic cancer. The expression levels of MMR and PD-L1 genes were downloaded from the GEPIA and GEO databases to analyze the correlation between MMR genes and PD-L1, and the clinicopathological and survival information were downloaded from the TCGA databases to analyze the relationship between the expression of MMR, PD-L1 and clinicopathological characteristics, prognosis. Meanwhile, the tumor tissue samples of 41 patients with pancreatic cancer were collected, and the protein expression levels of MMR and PD-L1 were detected by immunohistochemical assay. Furthermore, we analyzed the correlation between MMR and PD-L1, and the correlation between the expression of MMR, PD-L1 and clinicopathological characteristics, prognosis of pancreatic cancer patients. Results: Bioinformatics analysis showed that MLH1, MLH3, MSH2, MSH3, and PMS2 were highly expressed in most cancer types including pancreatic cancer (P P = 0.012), clinical stage (I vs II: P = 0.016), MSH2 expression was related to clinical stage (P < 0.05), T stage (T3 vs T4: P = 0.039), and MSH3 expression was related to T stage (P < 0.05). Besides, both MSH2 expression (P P = 0.044) were significantly associated with prognosis. GEPIA data also showed that MSH2 expression was related to prognosis (P = 0.008). The correlation analysis revealed that the expressions MSH2, MLH1, PMS2 had strong correlations with PD-L1 both in GEPIA and GEO databases. Real-world data indicated that of the 41 pancreatic cancer patients, 5 cases had MLH1 deletion, 5 cases had MSH2 deletion, 4 cases had PMS2 deletion, and 12 cases had PD-L1 positive expression. Notably, PMS2 deletion was associated with PD-L1 positive expression (P = 0.035). In addition, MLH1 was related to clinical stage (P = 0.033), age (P = 0.048), and MSH2 was related to clinical stage (P = 0.033). However, MLH1 (P = 0.697), MSH2 (P = 0.956), PMS2 (P = 0.341), and PD-L1 (P = 0.734) appeared to have no impact on overall survival among patients with pancreatic cancer. Conclusion: Both bioinformatics and real-world data showed that there were correlation between PMS2 deletion and PD-L1 expression, and correlation between MLH1, MSH2 and clinical stage.

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。

lncRNA TUG1靶向调节miR-31-5p对急性胰腺炎小鼠炎症反应的影响

目的:探讨长链非编码RNA牛磺酸上调基因1(lncRNA TUG1)在急性胰腺炎(AP)中的作用机制。方法:体外培养小鼠胰腺腺泡细胞系(MPC-83),用脂多糖(LPS,10μg/ml)和雨蛙素(Caerulein,100 nmol/L)处理3 h,建立AP模型。实验分为对照组(control组)、AP组、AP+sh-NC组、AP+sh-TUG1组、AP+sh-TUG1+inhibitor-NC组、AP+sh-TUG1+miR-31-5p inhibitor组。实时荧光定量PCR(qRT-PCR)检测细胞中lncRNA TUG1和miR-31-5p表达水平;CCK-8法检测细胞活力;流式细胞术检测细胞凋亡;ELISA检测细胞上清液中IL-1β、肿瘤坏死因子α(TNF-α)水平;双荧光素酶报告基因实验验证lncRNA TUG1和miR-31-5p之间的靶向关系。构建AP小鼠模型,给予相应的干预后,qRT-PCR检测胰腺组织中lncRNA TUG1和miR-31-5p表达水平;试剂盒检测血清中炎症因子IL-1β、TNF-α含量和淀粉酶(AMY)和脂肪酶(Lipase)活性;HE染色观察胰腺组织病理学变化;TUNEL检测胰腺组织中细胞凋亡。结果:在Caerulein和LPS共同处理的MPC-83细胞中lncRNA TUG1水平、细胞凋亡率、IL-1β和TNF-α水平升高,miR-31-5p水平、细胞活力降低(均P<0.05);敲低lncRNA TUG1可上调miR-31-5p,增加细胞活力,降低IL-1β和TNF-α水平,抑制细胞凋亡(均P<0.05);下调miR-31-5p表达可减弱敲低lncRNA TUG1对细胞炎症反应的抑制作用。miR-31-5p是lncRNA TUG1的直接靶标。在体内敲低lncRNA TUG1表达可上调AP小鼠胰腺组织中miR-31-5p表达,降低IL-1β、TNF-α水平,减少细胞凋亡,改善胰腺组织损伤。结论:敲低lncRNA TUG1可能通过上调miR-31-5p表达水平,抑制炎症反应,改善AP。

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.

Emodin and baicalein inhibit pancreatic stromal derived factor-1 expression in rats with acute pancreatitis

BACKGROUND: Stromal derived factor-1 (SDF-1) is an efficacious leukocyte chemoattractant, which can attract lymphocytes and mononuclear cells from bloodstream into the site of inflammation. Emodin., an anthraquinone derivative from Radix et Rhizoma Rhei, and baicalein, a flavone from Scutellaria baicalensis Georgi, both have been reported to possess anti-inflammatory activities. The expression pattern of SDF-1 in experimental acute pancreatitis (AP) and the effect of emodin or baicalein on that are not well defined. The present study aimed to investigate the effects of emodin and baicalein on pancreatic myeloperoxidase (MPO) activity (reflecting leukocyte sequestration) and cytokine production, as well as tissue SDF-1 expression in the setting of AP. METHODS: A :rat model of AP was induced by administration (of 5% sodium taurocholate through the biliopancreatic duct. The level of tumor necrosis factor-a (TNF-alpha), interleukin-6 (IL-6) and MPO in the pancreas, and serum amylase were tested by immunohistochemistry, ELISA and chromatometry. The expressions of SDF-1 alpha and SDF-1 beta were detected by real-time PCR, Western blotting, and immunohistochemistry. RESULT: Combination of emodin and baicalein significantly reduced pancreatic TNIP-alpha, IL-6 and MPO, and also inhibited pancreatic SDF-1 expression. CONCLUSIONS: The inhibition of SDF-1 expression by emodin and baicalein might contribute, in part at least, to the amelioration of pancreatic inflammation. The present study also shows benefits of simultaneous treatment of AP.

S-1 in the treatment of pancreatic cancer

S-1 is an oral 5-fluorouracil(5-FU) prodrug,which is designed to improve the antitumor activity of 5-FU by inhibiting dihydropyrimidine dehydrogenase,the key enzyme of 5-FU catabolism.Recently,two important studies on the clinical use of S-1 for pancreatic cancer have been reported from Japan.In the first study(GEST study),S-1 demonstrated non-inferiority to gemcitabine(GEM) in overall survival(OS) for metastatic or locally advanced pancreatic cancer,but combination chemotherapy with GEM and S-1 did not show superiority to GEM in OS.In the second study(JASPAC-01 study),S-1 showed superiority to adjuvant chemotherapy with GEM in OS in patients with resected pancreatic cancer.In addition to GEM,S-1 is now regarded as the key drug in the management of pancreatic cancer in Japan.To date,many studies have investigated the effectiveness of S-1 in various settings,such as first-line chemotherapy for metastatic or locally advanced pancreatic cancer,second-line chemotherapy after GEM failure,and chemoradiotherapy for locally advanced disease.In this review,we focus on recent clinical trials of S-1-based chemotherapy for advanced pancreatic cancer.