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.

KAI1 is a potential target for anti-metastasis in pancreatic cancer cells

AIM: To investigate whether KAI1, as a metastasis suppressor gene, is associated with invasive and metastatic ability of pancreatic cancer cells.METHODS: KAI1 gene was transfected into pancreatic cancer cell line MiaPaCa Ⅱ by liposomes selected with G418. Expression of transfected cells was measured by Western blotting, immunofluorescence and immunocytochemistry. Tumor cell invasion and metastatic ability were detected through gelatinase activity and reconstituted basement membrane (Matrigel) assay. pCMV-KAI1 was directly injected into the heterotopic human pancreatic adenocarcinoma successfully established in the groin of BALB/C nude mice, by subcutaneous injection of MiaPaCa Ⅱ pancreatic cancer cells. The statistical analysis between groups was determined by Student's two tailed t test.RESULTS: By Western blotting, MiaPaCa Ⅱ cells transfected by KAI1 gene indicated KAI1 expression at approximately 29.1 kDa. Cytoplasm staining was positive and uniformly spread in transfected cancer cells, using immunohistochemistry and immunofluorescence. The most obvious difference was present after 30 h (MiaPaca Ⅱ 43.6 ± 9.42, pCMV-MiaPaca Ⅱ 44.8 ± 8.56, pCMV-KAI1-MiaPaca Ⅱ 22.0 ± 4.69, P < 0.05). Gelatinolysis revealed a wider and clearer band of gelatinolytic activity in non-transfected than in transfected cells (MiaPaCa Ⅱ cells 30.8 ± 0.57, transfected cells 28.1 ± 0.65, P < 0.05). In vivo tumor growth rates of KAI1 transfectants with KAI1-Lipofectamine 1.22 ± 0.31 in A group were lower than control 4.61 ± 1.98 and pCMV-KAI 11.67 ± 0.81. Analyses of metastases with and without KAI1 transfection in mice were different in liver and lung between controls 1.62 ± 0.39, 0.45 ± 0.09, pCMV-KAI 1.01 ± 0.27, 0.33 ± 0.09 and KAI1-Lipofectamine 0.99 ± 0.21, 0.30 ± 0.09 respectively (P < 0.05).CONCLUSION: High expression of KAI1 gene was found in transfected MiaPaCa Ⅱ human pancreatic cancer cells with lower metastatic ability. KAI1 gene plays an important role in inhibiting metastasis of pancreatic cancer after direct injection into pancreatic adenocarcinoma. These results show that the suppressed invasion and motor function of pancreatic cancer cells may be a key reason why the KAI1 gene controls pancreatic cancer cell metastasis.

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.

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.

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.

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.

KAI1 inhibits HGF-induced invasion of pancreatic cancer by sphingosine kinase activity

BACKGROUND:KAI1/CD82 has been reported to attenuate the process of metastases in a variety of tumors;however,its mechanism of action in invasion has not been fully elucidated. The present study aimed to investigate the importance of KAI1 in invasion and its correlation with activation of sphingosine kinase(SPK)in human pancreatic cancer PANC1 and Miapaca-2 cell lines. METHODS:The expression of KAI1 in PANC1 and Miapaca-2 cells,which was mediated by recombinant adenovirus(Ad-KAI1), was assessed by a flow cytometer and Western blotting.After successful infection was established,in vitro growth curve and invasive ability in Boyden Chamber assay were studied.The presence of KAI1 correlating with c-Met and SPK was detected by co-immunoprecipitation and[γ-32P]ATP incorporation. RESULTS:KAI1 genes had no significant effects on the curve representing cell growth.After infection with the KAI1 gene,decreased invasive ability in the Boyden Chamber assay was observed in PANC1 and Miapaca-2 cells that were induced by hepatocyte growth factor.Over-expression of KAI1 in the cells led to the deactivation of SPK and a decreased level of intracellular sphingosine-1-phosphate.No correlation was observed between c-Met and KAI1 during co-immunoprecipitation. CONCLUSION:The results of this study for the first time demonstrated a regulatory role for KAI1 in SPK activation, which leads to decreased invasive ability in disease progression of human pancreatic cancer.

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。

Novel therapeutic targets for pancreatic cancer

Pancreatic cancer has become the fourth leading cause of cancer death in the last two decades. Only 3%-15% of patients diagnosed with pancreatic cancer had 5 year survival rate. Drug resistance, high metastasis, poor prognosis and tumour relapse contributed to the malignancies and difficulties in treating pancreatic cancer. The current standard chemotherapy for pancreatic cancer is gemcitabine, however its efficacy is far from satisfactory, one of the reasons is due to the complex tumour microenvironment which decreases effective drug delivery to target cancer cell. Studies of the molecular pathology of pancreatic cancer have revealed that activation of KRAS, overexpression of cyclooxygenase-2, inactivation of p16INK4A and loss of p53 activities occurred in pancreatic cancer. Co-administration of gemcitabine and targeting the molecular pathological events happened in pancreatic cancer has brought an enhanced therapeutic effectiveness of gemcitabine. Therefore, studies looking for novel targets in hindering pancreatic tumour growth are emerging rapidly. In order to give a better understanding of the current findings and to seek the direction in future pancreatic cancer research; in this review we will focus on targets suppressing tumour metastatsis and progression, KRAS activated downstream effectors, the relationship of Notch signaling and Nodal/Activin signaling with pancreatic cancer cells, the current findings of non-coding RNAs in inhibiting pancreatic cancer cell proliferation, brief discussion in transcription remodeling by epigenetic modifiers (e.g., HDAC, BMI1, EZH2) and the plausible therapeutic applications of cancer stem cell and hyaluronan in tumour environment.

Pathophysiological roles of Pim-3 kinase in pancreatic cancer development and progression

Pim-3 is a member of the provirus integration site for Moloney murine leukemia virus(Pim)family proteins that exhibit serine/threonine kinase activity.Similar to the other Pim kinases(Pim-1 and Pim-2),Pim-3 is involved in many cellular processes,including cell proliferation,survival,and protein synthesis.Although Pim-3is expressed in normal vital organs,it is overexpressed particularly in tumor tissues of endoderm-derived organs,including the liver,pancreas,and colon.Silencing of Pim-3 expression can retard in vitro cell proliferation of hepatocellular,pancreatic,and colon carcinoma cell lines by promoting cell apoptosis.Pim-3 lacks the regulatory domains similarly as Pim-1 and Pim-2 lack,and therefore,Pim-3 can exhibit its kinase activity once it is expressed.Pim-3 expression is regulated at transcriptional and post-transcriptional levels by transcription factors(e.g.,Ets-1)and post-translational modifiers(e.g.,translationally-controlled tumor protein),respectively.Pim-3 could promote growth and angiogenesis of human pancreatic cancer cells in vivo in an orthotopic nude mouse model.Furthermore,a Pim-3 kinase inhibitor inhibited cell proliferation when human pancreatic cancer cells were injected into nude mice,without inducing any major adverse effects.Thus,Pim-3 kinase may serve as a novel molecular target for developing targeting drugs against pancreatic and other types of cancer.

Immunotherapy in pancreatic cancer:Unleash its potential through novel combinations

Pancreatic cancer is the third leading cause of cancer mortality in both men and women in the United States,with poor response to current standard of care,short progression-free and overall survival.Immunotherapies that target cytotoxic T lymphocyte antigen-4,programmed cell death protein-1,and programmed death-ligand 1 checkpoints have shown remarkable activities in several cancers such as melanoma,renal cell carcinoma,and nonsmall cell lung cancer due to high numbers of somatic mutations,combined with cytotoxic T-cell responses.However,single checkpoint blockade was ineffective in pancreatic cancer,highlighting the challenges including the poor antigenicity,a dense desmoplastic stroma,and a largely immunosuppressive microenvironment.In this review,we will summarize available clinical results and ongoing efforts of combining immune checkpoint therapies with other treatment modalities such as chemotherapy,radiotherapy,and targeted therapy.These combination therapies hold promise in unleashing the potential of immunotherapy in pancreatic cancer to achieve better and more durable clinical responses by enhancing cytotoxic T-cell responses.

Doublecortin and CaM kinase-like-1 as an independent prognostic factor in patients with resected pancreatic carcinoma

To elucidate the effect of expression of doublecortin and CaM kinase-like-1 (DCLK1) in patients with pancreatic ductal adenocarcinoma (PDAC). METHODSTumor specimens were obtained from 136 patients with pancreatic cancer who had undergone resection without preoperative therapy between January 2000 and December 2013 at the Department of Surgical Oncology, Osaka City University. The resected specimens were analyzed for associations with clinicopathological data, including DCLK1 expression, epithelial mesenchymal transition (EMT) marker expression, and cancer stem cell (CSC) marker expression. Univariate and multivariate survival analyses were performed and we assessed the association between DCLK1 expression and clinicopathological factors, including the EMT marker and CSC marker. RESULTSIn total, 48.5% (66/136) of the pancreatic cancer samples were positive for DCLK1. Patients with DCLK1-positive tumors had significantly shorter survival times than those with DCLK1-negative tumors (median, 18.7 mo vs 49.5 mo, respectively; P < 0.0001). Positive DCLK1 expression correlated with histological grade (P = 0.0290), preoperative CA19-9 level (P = 0.0060), epithelial cell adhesion molecule (EpCAM) expression (P = 0.0235), and the triple-positive expression of CD44/CD24/EpCAM (P = 0.0139). On univariate survival analysis, five factors were significantly associated with worse overall survival: histological grade of G2 to G4 (P = 0.0091), high preoperative serum SPan-1 level (P = 0.0034), R1/2 (P < 0.0001), positive expression of DCLK1 (P < 0.0001) or CD44 (P = 0.0245). On multivariate survival analysis, R1/2 [odds ratio (OR) = 2.019, 95% confidence interval (CI): 1.380-2.933; P = 0.0004] and positive DCLK1 expression (OR = 1.848, 95%CI: 1.2854-2.661; P = 0.0009) were independent prognostic factors. CONCLUSIONDCLK1 expression was found to be an independent prognostic factor and it may play a crucial prognostic role by promoting acquisition of stemness.

CYP3A5 unexpectedly regulates glucose metabolism through the AKT-TXNIP-GLUT1 axis in pancreatic cancer

CYP3A5 is a cytochrome P450(CYP)enzyme that metabolizes drugs and contributes to drug resistance in cancer.However,it remains unclear whether CYP3A5 directly influences cancer progression.In this report,we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma.Multi-omics analysis showed that CYP3A5 knockdown re-sults in a decrease in various glucose-related metabolites through its effect on glucose trans-port.A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP,a negative regulator of GLUT1.Notably,CYP3A5-generated reactive oxygen species were proved to be responsible for atten-uating the AKT-4EBP1-TXNIP signaling pathway.CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer.Taken together,our results,for the first time,reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.

分泌型PD-1抗体可提高c-Met CAR-T细胞对胰腺癌细胞的杀伤作用

目的设计并制备能够分泌PD-1抗体和靶向c-Met的CAR-T细胞,以消除肿瘤对CAR-T细胞的免疫抑制作用,从而提高CAR-T细胞对胰腺癌的治疗效果。方法采用Kaplan-Meier Plotter、GEPIA和Timer2.0生物信息学数据库,分析c-Met在胰腺癌中的表达、生存期及免疫浸润。免疫组化检测胰腺癌临床样本c-Met和PD-L1表达,流式细胞术验证胰腺癌细胞Aspc-1 c-Met和PD-L1表达通过基因编辑将PD-1分泌型抗体和HIS标签连接至2代c-Met CAR分子后,构建PD-1/c-Met CAR质粒并包被慢病毒,慢病毒感染至活化T细胞内,通过流式细胞技术检测CAR-T阳性率和细胞亚群;Western blotting检测分泌型PD-1抗体在细胞上清液中的存在;体外功能试验中,通过LDH释放实验检测CAR-T对靶细胞的杀伤效率,CCK-8检测靶细胞存在下PD-1抗体对CAR-T增殖的促进作用。ELISA检测PD-1/c-Met CAR-T和c-Met CAR-T活化后细胞因子的分泌量。结果生信分析结果显示,胰腺癌组织c-Met表达高于正常组织(P<0.01);c-Met表达水平与胰腺癌患者生存期呈负相关(P<0.01)。c-Met的表达可能与多种免疫细胞浸润成正相关。免疫组化结果显示,胰腺癌c-Met和PD-L1表达均高于癌旁组织(P<0.01);流式细胞术结果显示,Aspc-1细胞c-Met和PD-L1表达量为90.7%和57.7%,琼脂糖凝胶电泳显示成功制备四代PD-1/c-Met CAR分子;流式细胞术和Western blotting显示,成功构建PD-1/c-Met CAR-T且PD-1抗体可顺利分泌。体外功能验证中LDH结果显示,PD-1/c-Met CART对肿瘤细胞杀伤效率在效靶比为20:1时高于c-Met CAR-T(P<0.01);CCK-8实验结果显示,靶细胞刺激72 h后增殖效率高于c-Met CAR-T(P<0.01);ELISA结果显示,PD-1/c-Met CAR-T分泌的细胞因子IL-2和TNF-α高于c-Met CAR-T(P<0.01)。结论PD-1抗体分泌型c-Met CAR-T可成功构建,并在体外胰腺癌细胞上显示出优于c-Met CAR-T肿瘤杀伤效率和增殖效率。

MicroRNA-105-5p/PPM1A对胰腺癌PANC-1细胞增殖、迁移及侵袭的机制研究

目的探讨microRNA-105-5p(miR-105-5p)/PPM1A对胰腺癌PANC-1细胞增殖、迁移、侵袭及上皮细胞向间质转化(EMT)进程的影响及其潜在作用机制。方法实时荧光定量聚合酶链反应(qRT-PCR)检测miR-105-5p在人胰腺导管上皮细胞hTRET-HPNE和胰腺癌细胞PANC-1、AsPC-1、Bxpc-3中的表达。利用Kaplan-Meier Plotter在线工具探讨miR-105-5p与胰腺癌患者预后的关系。在PANC-1细胞中分别转染mimic NC、miR-105-5p mimic、inhibitor NC、miR-105-5p inhibitor。CCK-8法、划痕实验、Transwell实验分别检测各组细胞的增殖、迁移及侵袭能力;qRT-PCR检测miR-105-5p对E-cadherin、N-cadherin、Vimentin、ZEB1表达的影响。生物信息学方法预测miR-105-5p的候选靶基因,并对候选靶基因进行GO和KEGG富集分析。双萤光素酶实验检测miR-105-5p与PPM1A的靶向关系。qRT-PCR检测在PANC-1细胞中分别转染mimic NC、miR-105-5p mimic、inhibitor NC、miR-105-5p inhibitor后PPM1A的表达。免疫荧光实验检测PPM1A在人胰腺导管上皮细胞hTRET-HPNE和胰腺癌细胞PANC-1、AsPC-1、Bxpc-3中的表达。在PANC-1细胞中分别转染mimic NC+pcDNA3.1、mimic NC+pcDNA3.1-PPM1A、miR-105-5p mimic+pcDNA3.1-PPM1A后,通过挽救实验进一步研究miR-105-5p inhibitor与PPM1A在胰腺癌细胞中的相互作用关系。结果胰腺癌细胞PANC-1、AsPC-1、Bxpc-3中miR-105-5p mRNA相对表达量高于hTRET-HPNE细胞中miR-105-5p mRNA相对表达量(P<0.05),以PANC-1细胞中的相对表达量最高。miR-105-5p高表达与胰腺癌患者的不良预后有关(P<0.05)。miR-105-5p mimic组细胞增殖、迁移及侵袭能力均高于mimic NC组(P<0.05)。与mimic NC比较,miR-105-5p mimic下调E-cadherin mRNA表达,上调N-cadherin、Vimentin、ZEB1 mRNA表达(P<0.05)。转染miR-105-5p inhibitor后得到相反的结果。双萤光素酶实验证实miR-105-5p与PPM1A存在靶向关系。免疫荧光实验显示在胰腺癌细胞PANC-1、AsPC-1、Bxpc-3中PPM1A的荧光强度低于人胰腺导管上皮细胞hTRET-HPNE(P<0.05)。挽救实验表明miR-105-5p可部分挽救PPM1A对PANC-1细胞增殖、迁移和侵袭的抑制作用(P<0.05)。结论miR-105-5p靶向PPM1A促进胰腺癌PANC-1细胞的增殖、迁移及侵袭。

槐定碱对人胰腺癌细胞株capan-1增殖及侵袭能力的影响

目的探讨槐定碱对人胰腺癌细胞株capan-1增殖和侵袭能力的影响。方法用MTT法检测不同浓度的槐定碱对capan-1细胞增殖的影响,Transwll实验检测槐定碱对capan-1细胞侵袭能力的影响,ELISA实验检测MMP-2和MMP-9表达水平。结果不同浓度的槐定碱均能明显抑制capan-1细胞生长(P<0.05);与空白对照组比较,槐定碱1.25、2.5、5 g·L-1组capan-1细胞MMP-2和MMP-9表达水平明显降低,差异有统计学意义(P<0.05)。结论槐定碱能通过下调MMPs的表达水平,有效地抑制capan-1细胞增殖,降低细胞侵袭能力。

Regulation of CD137 expression through K-Ras signaling in pancreatic cancer cells

Background:The interaction between CD137 and its ligand(CD137L)plays a major role in the regulation of immune functions and affects cancer immunotherapy.CD137 is a cell surface protein mainly located on activated T cells,and its regulation and functions in immune cells are well established.However,the expression of CD137 and its regulation in cancer cells remain poorly understood.The main purposes of this study were to examine the expression of CD137 in pancreatic cancer cells and to investigate its underlying mechanisms.Methods:Cells containing inducible K-RasG12V expression vector or with different K-Ras mutational statuses were used as in vitro models to examine the regulation of CD137 expression by K-Ras.Various molecular assays were employed to explore the regulatory mechanisms.Tumor specimens from 15 pancreatic cancer patients and serum samples from 10 patients and 10 healthy donors were used to test if the expression of CD137 could be validated in clinical samples.Results:We found that the CD137 protein was expressed on the cell surface in pancreatic cancer tissues and cancer cell lines.Enzyme-linked immunosorbent assay revealed no difference in the levels of secreted CD137 in the sera of patients and healthy donors.By using the K-Ras inducible cell system,we further showed that oncogenic K-Ras up-regulated CD137 through the activation of MAPK(mitogen-activated protein kinases)and NF-κB(nuclear factor kappa-light-chain-enhancer of activated B cells)pathways,as evidenced by significantly reduced CD137 mRNA expression led by genetic silencing of MAPK1 and p65,the key proteins involved in the respective pathways.Further-more,we also found that the NF-κB pathway was mainly stimulated by the K-Ras-induced secretion of interleukin-1α(IL-1α)which promoted the transcription of the CD137 gene in pancreatic cancer cell lines.Analysis of the TCGA(the cancer genome atlas)database also revealed a significant correlation between IL-1αand CD137 expression(r=0.274)in tumor samples from pancreatic cancer patients(P<0.001).Conclusions:The present study has demonstrated that the CD137 protein was expressed on pancreatic cancer cell surface,and has identified a novel mechanism by which K-Ras regulates CD137 in pancreatic cancer cells through MAPK and NF-κB pathways stimulated by IL-1α.

胰腺癌组织中MIB1、MAL2表达与患者临床病理特征及预后的关系

目的研究胰腺癌中Mindbomb同源物1(MIB1)、T细胞分化蛋白2(MAL2)的表达与患者临床病理特征及预后的关系。方法选取2018年1月至2020年1月该院诊治的82例胰腺癌患者为研究对象。荧光定量PCR及免疫组化染色检测胰腺癌组织和癌旁组织中MIB1、MAL2 mRNA及蛋白表达。比较MIB1、MAL2 mRNA表达与胰腺癌患者临床病理特征的关系。相关性分析采用Pearson相关分析。采用Kaplan-Meier生存曲线分析MIB1、MAL2 mRNA表达与生存预后的关系。单因素和多因素Cox回归分析影响胰腺癌患者预后的因素。结果胰腺癌组织中MIB1、MAL2阳性表达率95.12%(78/82)、97.56%(80/82),明显高于癌旁组织7.32%(6/82)、9.76%(8/82),差异有统计学意义(P<0.05)。胰腺癌组织中MIB1、MAL2 mRNA表达分别为(3.02±0.66)、(6.65±1.19),明显高于癌旁组织(1.83±0.40)、(3.56±0.68),差异有统计学意义(P<0.05)。胰腺癌组织中MIB1与MAL2 mRNA表达呈显著正相关(r=0.427,P<0.05)。不同肿瘤分期及淋巴结转移胰腺癌组织中MIB1、MAL2 mRNA表达比较差异有统计学意义(P<0.05)。MIB1 mRNA高表达组患者累积生存率显著低于低表达组患者(χ^(2)=39.338,P<0.001)。MAL2 mRNA高表达组患者累积生存率显著低于低表达组患者(χ^(2)=50.306,P<0.001)。肿瘤分期ⅡB~Ⅲ期、伴淋巴结转移、MIB1 mRNA高表达、MAL2 mRNA高表达是影响胰腺癌患者不良生存预后的独立危险因素。结论胰腺癌中MIB1、MAL2表达升高,两者表达与不良临床病理特征有关,是新的胰腺癌预后相关肿瘤标志物。

CXXC4调控胰腺癌PANC-1细胞迁移和侵袭的实验研究

目的探究CXXC指蛋白4(CXXC4)对胰腺癌PANC-1细胞迁移、侵袭及上皮-间充质转化(EMT)进程的影响。方法组织芯片免疫组织化学染色实验检测14份癌旁胰腺组织和87份胰腺癌组织中CXXC4表达情况。采用免疫荧光实验检测人正常胰腺导管上皮细胞HPNE及人胰腺癌细胞PANC-1、AsPC-1和BxPC-3中CXXC4蛋白的表达水平。采用Western blot实验检测CXXC4敲降和过表达的转染有效性,划痕和Transwell实验分析敲降或过表达CXXC4对PANC-1细胞迁移、侵袭的影响。采用Western blot和免疫荧光实验检测细胞EMT标志物E-cadherin、Vimentin和ZEB2的表达水平。通过STRING网站预测与CXCC4有相互作用的蛋白,筛选出的蛋白进行GO和KEGG富集分析。结果免疫组化分析结果表明,CXXC4在胰腺癌组织中的表达水平低于癌旁胰腺组织(P<0.05)。免疫荧光实验结果显示,与HPNE细胞相比,CXXC4在PANC-1、AsPC-1和BxPC-3中的荧光强度均显著降低(均P<0.05)。划痕和Transwell实验结果显示,与si-NC组相比,si-CXXC4组PANC-1细胞迁移和侵袭能力增强(P<0.05);与pcDNA3.1组相比,pcDNA3.1-CXXC4组PANC-1细胞迁移和侵袭能力减弱(P<0.05)。Western blot和免疫荧光实验结果显示,与si-NC组(结果标准化为1)相比,si-CXXC4组PANC-1细胞上皮样细胞标志物E-cadherin蛋白表达(0.48±0.10)降低(P<0.05),而间充质样标志物Vimentin(1.42±0.06)和ZEB2(1.86±0.06)的表达升高(P<0.05);与pcDNA3.1组(结果标准化为1)相比,pcDNA3.1-CXXC4组PANC-1细胞上皮样细胞标志物E-cadherin蛋白表达(2.21±0.42)升高(P<0.05),而间充质样标志物Vimentin(0.54±0.05)和ZEB2(0.39±0.02)蛋白表达降低(P<0.05)。STRING网站预测出9个蛋白与CXXC4有密切的作用。结论CXXC4抑制胰腺癌PANC-1细胞迁移、侵袭及EMT进程。

多层螺旋CT联合CA19-9、CEACAM1、CA242检测在胰腺癌诊断中的效能

目的:探讨多层螺旋CT(MSCT)联合血清糖类抗原19-9(CA19-9)、糖类抗原242(CA242)、癌胚抗原相关细胞黏附分子1(CEACAM1)检测在胰腺癌诊断中的效能。方法:选取2019年1月至2020年12月该院收治的107例疑似胰腺癌患者为研究对象,所有患者均行MSCT扫描,并检测血清CA19-9、CEACAM1、CA242水平,以病理结果为金标准,绘制受试者工作特征曲线(ROC),分析MSCT联合血清CA19-9、CA242、CEACAM1检测在胰腺癌诊断中的效能。结果:病理结果显示,胰腺癌45例,占42.06%;胰腺良性病变62例,占57.94%。两组门脉期、胰腺期ΔCT值比较,差异无统计学意义(P>0.05);胰腺癌组动脉期ΔCT值大于胰腺良性病变组,差异有统计学意义(P<0.05)。胰腺癌组CA19-9、CA242、CEACAM1水平均高于胰腺良性病变组,差异有统计学意义(P<0.05)。ROC曲线分析结果显示,MSCT(动脉期ΔCT值)、CA19-9、CA242、CEACAM1单项及联合检测诊断胰腺癌的曲线下面积依次为0.743、0.842、0.764、0.861、0.932,联合检测诊断胰腺癌的效能高于各单项检测。结论:MSCT、血清CA19-9、CA242、CEACAM1联合检测诊断胰腺癌的效能高于各单项检测。