胃复春对不同NLR水平的胃早癌ESD术后患者的消化道症状、胃肠激素、胃功能指标和血常规指标的影响

背景胃复春可治疗内镜下剥离术(endoscopic submucosal dissection,ESD)后的胃早癌患者,中性粒细胞-淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)可作为评估此类患者活动度和预后的指标.目前尚未确定不同NLR水平的ESD术后胃早癌患者是否存在与之相关的胃复春疗效差异.目的探讨胃复春对不同NLR水平的胃早癌ESD术后患者的治疗效果.方法选取本院2020-01/2022-12收治的160例胃早癌ESD术后患者,将其分为常规治疗组(n=40)和常规治疗+胃复春治疗组(n=120).将胃复春治疗组再按照NLR水平进行三分位分组,分为高三分位组(NLR≥3.23)40例,低三分位组(NLR≤1.74)40例,中三分位组(NLR:1.74-3.23)40例.比较以上各组治疗前后的主要的消化道症状评分、胃肠激素水平、胃功能指标及血常规指标水平,并计算治疗的总有效率.结果与治疗前比较,治疗后各组患者的胃脘灼热、胃脘胀满、胃脘疼痛和胃纳呆滞评分均降低(P<0.05),其中以低三分位组治疗效果最佳(P<0.05),总有效率最高(P<0.05).常规治疗不能改变患者NLR与血小板-淋巴细胞比值(platelet to lymphocyte ratio,PLR)水平,而常规治疗+胃复春治疗能降低患者的NLR与PLR水平(P<0.05).治疗后,与常规治疗组比较,胃复春治疗组(低、中和高三分位组)的抑胃肽、胃动素、胃泌素、胃蛋白酶原Ⅰ和胃蛋白酶原比值水平均增高(P<0.05)、白细胞、胃蛋白酶原Ⅱ和癌胚抗原均降低(P<0.05),其中以低三分位组最为明显.结论胃复春在不同NLR水平的胃早癌ESD术后患者中均显示出改善消化道症状、胃肠激素、胃功能指标和血常规指标的作用,尤其对于低NLR水平患者而言,治疗效果最为显著.在选择治疗方法时,建议优先考虑低NLR水平的胃早癌ESD术后患者使用胃复春进行治疗.

基于学科核心素养,立足浙大,讲好中国故事——“普通化学(H)”课程思政教学实践

课程思政要以“十年树木、百年树人”的精神,落实立德树人根本任务,发挥协同育人作用。本文介绍浙江大学“普通化学(H)”课程,融入课程思政的教育目标新梳理、教学思路新构建及课程思政案例新设计;分享以教师为主力、课程建设为主战场、课堂教学为主渠道,融合学科知识和育人元素,开展课程思政教学的具体实践。

Scientific connotation of “treating different diseases with the same method” from the perspective of metabolic-immune dysregulation in inflammation-mediated carcinogenesis of digestive organs

Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system.In the chronic inflammation microenvironment,the metabolic activity of tissue cells undergoes extensive changes,which interfere with the normal function of immune cells.Dysregulation of cell metabolism and immune function has been identified as a key factor contributing to inflammation-mediated carcinogenesis within the major digestive organs,such as the stomach,liver,and colorectum.This metabolic-immune imbalance also corresponds to traditional Chinese medicine(TCM)theories of“yin-yang disharmony”and“disharmony between Ying-nutrients and Wei-defense.”The metabolic-immune imbalance has also been regarded as the key factor supporting“treatment of different diseases with the same method”,in which the same approach is adopted in the treatment of different conditions.In the TCM treatment process,it is necessary to first identify TCM patterns and then apply the corresponding TCM to correct the dysregulated metabolic and immune function,thereby blocking the progression from inflammation to malignancy.Our study findings deepen the TCM understanding of metabolic-immune dysregulation and the relationship between metabolic-immune dysregulation,pattern identification,and treatment method.They also provide new insights for the treatment of inflammation-mediated carcinogenesis in major digestive organs and help us further explore the scientific connotation of the TCM strategy of“treating different diseases with the same method”.

12kV直动式快速真空开关研制

基于电磁斥力原理的操动机构始动时间短,可由增加电流的简单方式提高动作速度,非常适合于快速开关的应用场合。采用有限元方法仿真分析了金属盘厚度、线圈盘盖板和底板材质对斥力驱动机构特性的影响,并研制了一台基于斥力驱动装置和永磁保持装置的12 kV直动式快速真空开关。经测试和优化,该开关分闸始动时间达到0.5 ms以内,满行程时间达到5 ms以内,提高了分闸速度并增加了可靠性。

特高压变压器突发短路试验的可行性分析

在全球能源问题日益严峻的形势下,特高压交流输电技术将获得大量应用。特高压变压器作为输电线路的重要设备之一,其质量和可靠性直接关系到电力系统的安全稳定运行。目前,特高压变压器的抗短路电流能力还需依赖仿真验证的方式。该文从变压器短路试验要求出发,对1 000 k V等级特高压变压器开展短路试验的技术方案及最小系统需求进行了分析,并提出了大致的设备投资规模。

Puerarin protects brain tissue against cerebral ischemia/reperfusion injury by inhibiting the inflammatory response

Puerarin, a traditional Chinese medicine, exerts a powerful neuroprotective effect in cerebral ischemia/reperfusion injury, but its mechanism is unknown. Here, we established rat models of middle cerebral artery ischemia/reperfusion injury using the suture method. Puerarin （100 mg/kg） was administered intraperitoneally 30 minutes before middle cerebral artery occlusion and 8 hours after reperfusion. Twenty-four hours after reperfusion, we found that puerarin significantly improved neurological deficit, reduced infarct size and brain water content, and notably diminished the expression of Toll-like receptor-4, myeloid differentiation factor 88, nuclear factor kappa B and tumor necrosis factor-α in the ischemic region. These data indicate that puerarin exerts an anti-inflammatory protective effect on brain tissue with ischemia/reperfusion damage by downregulating the expression of multiple inflammatory factors.

Clinical significance of K-ras and BRAF mutations in Chinese colorectal cancer patients

AIM:To identify and assess mutations in the K-ras and BRAF genes in a cohort of Chinese patients with colorectal cancer (CRC) for their association with various clinicopathological parameters and prognosis.METHODS:Genomic DNA was isolated from frozen tissues.Pyrosequencing analysis was conducted to detect mutations in the K-ras (codons 12,13,and 61) and BRAF genes (codon 600).Statistical analysis was carried out using SPSS-15.0 software.RESULTS:Among the 118 colorectal cancer patients,we detected 41 (34.7%) mutations in the K-ras gene.Mutation frequencies at codon 12 and codon 13 were 23.7% (28/118) and 10.2% (12/118),respectively.Only one patient harbored a point mutation at codon 61 (0.8%,1/118).Gender was the only factor that showed an obvious relationship with K-ras gene mutation (female 44.7% vs male 28.2%,P=0.037).Other clinicopathological features,such as age,location of the tumor,tumor differentiation,Tumor,Node and Metastases classification,and the Union for International Cancer Control staging,showed no positive relationship with K-ras gene mutations.No significant correlation was observed between the presence of K-ras mutations (codons 12,13,and 61) and the survival of the patients.BRAF mutations were rare,and only two patients (1.7%) harbored a detectable mutation at codon 600.CONCLUSION:K-ras gene mutation is a common event in our 118 Chinese CRC patients,with an obvious relationship with gender.However,it seems not to be an independent prognostic factor in CRC patients.The BRAF gene is rarely mutated in Chinese CRC patients.

Different treatment strategies and molecular features between right-sided and left-sided colon cancers

The colon is derived from the embryological midgut and hindgut separately,with the right colon and left colon having different features with regards to both anatomical and physiological characteristics.Cancers located in the right and left colon are referred to as right colon cancer(RCC) and left colon cancer(LCC),respectively,based on their apparent anatomical positions.Increasing evidence supports the notion that not only are there differences in treatment strategies when dealing with RCC and LCC,but molecular features also vary between them,not to mention the distinguishing clinical manifestations.Disease-free survival after radical surgery of both RCC and LCC are similar.In the treatment of RCC,the benefit gained from adjuvant FOLFIRI chemotherapy is superior,or at least similar,to LCC,but inferior to LCC if FOLFOX regimen is applied.On the other hand,metastatic LCC exhibits longer survival than that of RCC in a palliative chemotherapy setting.For KRAS wild-type cancers,LCC benefits more from cetuximab treatment than RCC.Moreover,advanced LCC shows a higher sensitivity to bevacizumab treatment in comparison with advanced RCC.Significant varieties exist at the molecular level between RCC and LCC,which may serve as the cause of all apparent differences.With respect to carcinogenesis mechanisms,RCC is associated with known gene types,such as MMR,KRAS,BRAF,and mi RNA-31,while LCC is associated with CIN,p53,NRAS,mi RNA-146 a,mi RNA-147 b,and mi RNA-1288.Regarding protein expression,RCC is related to GNAS,NQO1,telomerase activity,P-PDH,and annexin A10,while LCC is related to Topo I,TS,and EGFR.In addition,separated pathways dominate progressionto relapse in RCC and LCC.Therefore,RCC and LCC should be regarded as two heterogeneous entities,with this heterogeneity being used to stratify patients in order for them to have the optimal,current,and novel therapeutic strategies in clinical practice.Additional research is needed to uncover further differences between RCC and LCC.

Prognostic and survival analysis of 837 Chinese colorectal cancer patients

AIM:To develop a prognostic model to predict survival of patients with colorectal cancer (CRC). METHODS:Survival data of 837 CRC patients undergoing surgery between 1996 and 2006 were collected and analyzed by univariate analysis and Cox proportional hazard regression model to reveal the prognostic factors for CRC. All data were recorded using a standard data form and analyzed using SPSS version 18.0 (SPSS, Chicago, IL, United States). Survival curves were calculated by the Kaplan-Meier method. The log rank test was used to assess differences in survival. Univariate hazard ratios and significant and independent predictors of disease-specific survival and were identified by Cox proportional hazard analysis. The stepwise procedure was set to a threshold of 0.05. Statistical significance was defined asP < 0.05. RESULTS:The survival rate was 74% at 3 years and 68% at 5 years. The results of univariate analysis suggested age, preoperative obstruction, serum carcinoembryonic antigen level at diagnosis, status of resection, tumor size, histological grade, pathological type, lymphovascular invasion, invasion of adjacent organs, and tumor node metastasis (TNM) staging were positive prognostic factors (P < 0.05). Lymph node ratio (LNR) was also a strong prognostic factor in stage Ⅲ CRC (P < 0.0001). We divided 341 stage Ⅲ patients into three groups according to LNR values (LNR1, LNR ≤ 0.33, n = 211; LNR2, LNR 0.34-0.66, n = 76; and LNR3, LNR ≥ 0.67, n = 54). Univariate analysis showed a significant statistical difference in 3-year survival among these groups:LNR1, 73%; LNR2, 55%; and LNR3, 42% (P < 0.0001). The multivariate analysis results showed that histological grade, depth of bowel wall invasion, and number of metastatic lymph nodes were the most important prognostic factors for CRC if we did not consider the interaction of the TNM staging system (P < 0.05). When the TNM staging was taken into account, histological grade lost its statistical significance, while the specific TNM staging system showed a statistically significant difference (P < 0.0001). CONCLUSION:The overall survival of CRC patients has improved between 1996 and 2006. LNR is a powerful factor for estimating the survival of stage Ⅲ CRC patients.

Chemotherapy and target therapy for hepatocellular carcinoma:New advances and challenges

Primary liver cancer is one of the commonest causes of death.Hepatocellular carcinoma(HCC) accounts for 90% of primary liver cancers.For patients with unresectable or metastatic HCC,conventional chemotherapy is of limited or no benefit.Sorafenib is the only systemic treatment to demonstrate a statistically significant but modest overall survival benefit,leading to an era of targeted agents.Many clinical trials of targeted drugs have been carried out with many more in progress.Some drugs like PTK787 showed potential benefits in the treatment of HCC.Despite these promising breakthroughs,patients with HCC still have a dismal prognosis.Recently,both a phase Ⅲ trial of everolimus and a phase Ⅱ clinical trial of trebananib failed to demonstrate effective antitumor activity in advanced HCC.Sorafenib still plays a pivotal role in advanced HCC,leading to further explorations to exert its maximum efficacy.Combinations targeted with chemotherapy or transarterial chemoembolization is now being tested and might bring about advances.New targeted agents such as mammalian target of rapamycin inhibitors are under investigation,as well as further exploration of the mechanism of hepatocarcinogenesis.

Helicobacter pylori infection, gastrin and cyclooxygenase-2 in gastric carcinogenesis

Gastric cancer is one of the most frequent neoplasms and a main cause of death worldwide, especially in China and Japan. Numerous epidemiological, animal and experimental studies support a positive association between chronic Helicobacter pylori(H. pylori) infection and the development of gastric cancer. However, the exact mechanism whereby H. pylori causes gastric carcinogenesis remains unclear. It has been demonstrated that expression of cyclooxygenase-2(COX-2) is elevated in gastric carcinomas and in their precursor lesions. In this review, we present the latest clinical and experimental evidence showing the role of gastrin and COX-2 in H. pylori-infected patients and their possible association with gastric cancer risk.

Special AT-rich sequence-binding protein 1 promotes cell growth and metastasis in colorectal cancer

AIM: To evaluate the expression of special AT-rich sequence-binding protein 1 (SATB1 ) gene in colorectal cancer and its role in colorectal cancer cell proliferation and invasion.METHODS: Immunohistochemistry was used to detect the protein expression of SATB1 in 30 colorectal cancer (CRC) tissue samples and pair-matched adjacent nontumor samples. Cell growth was investigated after enhancing expression of SATB1. Wound-healing assay and Transwell assay were used to investigate the impact of SATB1 on migratory and invasive abilities of SW480 cells in vitro . Nude mice that received subcutaneous implantation or lateral tail vein were used to study the effects of SATB1 on tumor growth or metastasis in vivo . RESULTS: SATB1 was over-expressed in CRC tissues and CRC cell lines. SATB1 promotes cell proliferation and cell cycle progression in CRC SW480 cells. SATB1 over-expression could promote cell growth in vivo . In addition, SATB1 could significantly raise the ability of cell migration and invasion in vitro and promote the ability of tumor metastasis in vivo . SATB1 could up-regulate matrix metalloproteases 2, 9, cyclin D1 and vimentin, meanwhile SATB1 could down-regulate E-cadherin in CRC. CONCLUSION: SATB1 acts as a potential growth and metastasis promoter in CRC. SATB1 may be useful as a therapeutic target for CRC.

Interaction of hepatitis C virus envelope glycoprotein E2 with the large extracellular loop of tupaia CD81

AIM: To further analyze the interaction of tupaia CD81 with hepatitis C virus (HCV) envelope protein E2. METHODS: A tupaia CD81 large extracellular loop (CD81 LEL), which binds to HCV E2 protein, was cloned and expressed as a GST-fusion protein, and interaction of HCV E2 protein with a tupaia CD81 LEL was evaluated by enzyme-linked immunosorbent assay (EIA). RESULTS: Although tupaia and human CD81 LEL differed in 6 amino acid changes, tupaia CD81 LEL was strongly recognized by anti-CD81 antibodies against human CD81 LEL conformation-dependent epitopes. Investigating LEL CD81-E2 interactions by EIA, we demonstrated that binding of tupaia CD81 LEL GST fusion protein to recombinant HCV E2 protein was markedly reduced compared to binding of human CD81 LEL GST fusion protein to recombinant HCV E2 protein. CONCLUSION: These data suggest that the structural differences in-between the tupaia and human CD81 may alter the interaction of the large extracellular loop with HCV envelope glycoprotein E2. These findings may be important for the understanding of the mechanisms of binding and entry of HCV to PTHs.

Integrin-linked kinase overexpression promotes epithelial-mesenchymal transition via nuclear factor-κB signaling in colorectal cancer cells

AIM: To investigate the effect of integrin-linked kinase(ILK) on proliferation, metastasis, and invasion of the colorectal cancer cell line SW480. METHODS: In this study, the colorectal cancer cell line SW480 was stably transfected with ILK plasmids, and small interfering RNA(si RNA) was used to knockdown expression of nuclear factor(NF)-κB/p65. Methylthiazole tetrazolium(MTT) assay was performed to measure proliferation, and the wound healing migration assay and matrigel invasion assay were used to test the metastasis and invasion ability of SW480 cells. To explore the epithelial-mesenchymal transition(EMT) process, embryonic development, and the invasion and metastasis of tumors, the protein level of E-cadherin, vimentin, snail, and slug was detected by western blot. Immunofluorescence was also used to detect E-cadherin expression. Western blot was used to determine the level of phosphorylated-inhibitor of kappa B(IκB)a, inhibitor of gamma B(IγB)a, and nuclear factor kappa B(NF-κB) expressions and toexplore the ILK signaling pathway. RESULTS: Western blot results revealed that ILK expression significantly increased when ILK was overexpressed in SW480 cells(P < 0.05). Proliferation, metastasis, and invasion ability were improved in the vector-ILK group compared to the vector group(P < 0.05). Immunofluorescence results revealed that E-cadherin fluorescence intensity decreased after ILK was overexpressed(P < 0.05). Western blot results revealed that the protein expression of E-cadherin was reduced, while vimentin, snail, and slug were upregulated when ILK was overexpressed in SW480 cells(P < 0.05). In order to determine the role of the NF-κB signaling pathway in ILK overexpression promoted EMT occurrence, we overexpressed ILK in SW480 cells and found that levels of NF-κB/p65 and cytoplasmic phosphorylated-IκBa were increased and that cytoplasmic IкBa levels were decreased compared to the control group(P < 0.05). Furthermore, NF-κB/p65 knockout revealed that E-cadherin was increased in the overexpressed ILK group. CONCLUSION: ILK overexpression improved the proliferation, metastasis, and invasion ability of SW480 cells, and this effect may be mediated by the NF-κB signaling pathway.

Flow Resistance Modeling for Coolant Distribution within Canned Motor Cooling Loops

Taylor–Couette–Poiseuille(TCP)flow dominates the inner water-cooling circulation of canned motor reactor coolant pumps.Current research on TCP flow focuses on torque behaviors and flow regime transitions through experiments and simulations.However,research on axial flow resistance in a large Reynolds number turbulent state is not sufficient,especially for the various flow patterns.This study is devoted to investigating the influence of annular flow on the axial flow resistance of liquid in the coaxial cylinders of the stator and rotor in canned motor reactor coolant pumps,and predicting the coolant flow distribution between the upper coil cooling loop and lower bearing lubricating loop for safe operation.The axial flow resistance,coupled with the annular rotation,is experimentally investigated at a flow rate with an axial Reynolds number,Rea,from 2.6×10~3 to 6.0×10~3 and rotational Reynolds number,Ret,from 1.6×10~4 to 4.0×10~4.It is revealed that the axial flow frictional coe cient varies against the axial flow rate in linear relation sets with logarithmic coordinates,which shift up when the flow has a higher Ret.Further examination of the axial flow resistance,with the Rea extending to 3.5×10~5 and Ret up to 1.6×10~5,by simulation shows gentle variation rates in the axial flow frictional coe cients against the Rea.The relation curves with different Ret values converge when the Rea exceeds 3.5×10~5.A prediction model for TCP flow consisting of a polygonal approximation with logarithmic coordinates is developed to estimate the axial flow resistance against different axial and rotational Reynolds numbers for the evaluation of heat and mass transfer during transition states and the engineering design of the canned motor chamber structure.

Anti-hepatitis C virus potency of a new autophagy inhibitor using human liver slices model

AIM: To evaluate the antiviral potency of a new antihepatitis C virus(HCV) antiviral agent targeting the cellular autophagy machinery. METHODS: Non-infected liver slices, obtained from human liver resection and cut in 350 μm-thick slices(2.7 × 106 cells per slice) were infected with cell culture-grown HCV Con1b/C3 supernatant(multiplicity of infection = 0.1) cultivated for up to ten days. HCV infected slices were treated at day 4 post-infection with GNS-396 for 6 d at different concentrations. HCV replication was evaluated by strand-specific real-time quantitative reverse transcription- polymerase chain reaction. The infectivity titers of supernatants were evaluated by foci formation upon inoculation into naive Huh-7.5.1 cells. The cytotoxic effect of the drugs was evaluated by lactate dehydrogenase leakage assays. RESULTS: The antiviral efficacy of a new antiviral drug, GNS-396, an autophagy inhibitor, on HCV infection of adult human liver slices was evidenced in a dosedependent manner. At day 6 post-treatment, GNS-396 EC50 was 158 nmol/L without cytotoxic effect(compared to hydroxychloroquine EC50 = 1.17 μmol/L).CONCLUSION: Our results demonstrated that our ex vivo model is efficient for evaluation the potency of autophagy inhibitors, in particular a new quinoline derivative GNS-396 as antiviral could inhibit HCV infection in a dosedependent manner without cytotoxic effect.

Statistic PID Tracking Control for Non-Gaussian Stochastic Systems Based on T-S Fuzzy Model

A new robust proportional-integral-derivative （PID） tracking control framework is considered for stochastic systems with non-Gaussian variable based on B-spline neural network approximation and T-S fuzzy model identification. The tracked object is the statistical information of a given target probability density function （PDF）, rather than a deterministic signal. Following B-spline approximation to the integrated performance function, the concerned problem is transferred into the tracking of given weights. Different from the previous related works, the time delay T-S fuzzy models with the exogenous disturbances are applied to identify the nonlinear weighting dynamics. Meanwhile, the generalized PID controller structure and the improved convex linear matrix inequalities （LMI） algorithms are proposed to fulfil the tracking problem. Furthermore, in order to enhance the robust performance, the peak-to-peak measure index is applied to optimize the tracking performance. Simulations are given to demonstrate the efficiency of the proposed approach.

肝星状细胞中细胞凋亡和存活的信号调控(英文)

肝星状细胞(hepatic stellate cells,HSCs)在肝脏纤维化发生过程中起着关键作用。当正常肝脏受到损伤时,HSCs由静息状态转分化为类肌成纤维细胞,并保持这种处于激活状态的表型,它们接收到的凋亡和存活的生物信号将决定激活态HSCs的最终细胞寿命。HSCs凋亡的发生与一系列复杂而又相互关联的生物信号传导和调控有关,HSCs凋亡信号来自于细胞膜受体,如死亡受体、神经生长因子受体和外周型苯甲二氮卓受体(peripheral-type benzodiazepine receptor) ;以及胞浆蛋白,如Bcl-2家族蛋白和细胞周期蛋白等。HSCs存活信号受到多种激酶和细胞因子的诱导,如金属蛋白酶组织抑制剂-1(tissue inhibitors of metalloproteinase-1)、Rho/Rho激酶、血小板源生长因子(platelet-derived growth factor)、转化生长因子-β1 (transforming growth factor-β1 )和胰岛素样生长因子(insulin-like growth factor-1)等。特异性地诱导HSCs发生凋亡是治疗肝脏纤维化的直接和有效手段,虽然目前对HSCs由激活态到静息状态的转归尚需进一步研究,但诱导HSCs凋亡将是治疗肝脏纤维化和肝硬化的研究热点和主要发展方向。

BMP-4 induced proliferation and oriented differentiation of rat hepatic oval cells into hepatocytes

Objective:To explore the role of bone morphogenetic protein 4(BMP-4) in hepatic progenitor cells(HPCs).Methods:The effect of BMP-4 on rat hepatic oval cells was examined by using the WB-F344 rat hepatocytic epithelial stem-cell-like cell line.This hepatocytic cell line could exert various hepatocytc functions including the secretion of albumin and urea.Immunohistochemistry was used to examine the effects of BMP-4 and its antagonist,Noggin,on the proliferation and differentiation of these cells,cellular uptake and excretion of indocyanine green,the periodic acid-schiff(PAS) assay for glycogen storage and the expression of hepatic markers.Results:Our results showed for the first time that BMP-4 may acted as a potential inducer of hepatic differentiation in rat hepatic oval cells.Conclusions:This cell source offers a much-needed attractive and expandable source for future investigations of drug screening,stem cell technologies and cellular transplantation,in a society with increasing levels of liver disease and damage.

Targeting X-linked inhibitor of apoptosis protein inhibits pancreatic cancer cell growth through p-Akt depletion

AIM: To determine whether lentivirus-mediated shRNA targeting the X-linked inhibitor of apoptosis protein (XIAP) gene could be exploited in the treatment of pancreatic cancer. METHODS: Human pancreatic cancer cells Panc-1, Mia-paca2, Bxpc-3 and SW1990, infected with lentivirus, were analyzed by real-time polymerase chain reaction (PCR). Western blotting was used to examine XIAP protein levels, survivin and p-Akt to confirm the result of real-time PCR and determine the possible mechanism. The 3-(4,5-cimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay was used to measure IC50 to determine chemosensitivity to the chemotherapeutic drugs 5-fluorouracil (5-FU) and gemcitabine. A colony assay, MTT assay and a tumorigenicity experiment were used to study cell proliferation in vitro and in vivo . Caspase-3/7 activity, 4',6-diamidino-2-phenylindole-staining and flow cytometric measurements were used to study apoptosis in SW1990 cells. RESULTS: XIAP proteins were found to be differen- tially expressed among pancreatic cancer cell lines Panc-1, Mia-paca2, Bxpc-3 and SW1990. Data of real-time PCR and Western blotting showed that XIAP was reduced persistently and markedly by lentivirus-mediated shRNA. Downregulation of XIAP by transfection with XIAP shRNA resulted in decreased p-Akt expression. XIAP shRNA also inhibited the growth of pancreatic cancer cells in vitro and in vivo , enhanced drug-induced apoptosis and increased chemosensitivity to 5-FU and gemcitabine. Results also suggest that inhibition of XIAP and subsequent p-Akt depletion may have an anti-tumor effect through attenuating the ability of cancer cells to survive. CONCLUSION: Lentivirus-mediated gene therapy is an attractive strategy in the treatment of pancreatic cancer and justifies the use of lentivirus in pancreatic cancer gene therapy studies.