胰腺星状细胞与胰腺癌的相互关系

胰腺癌是一种恶性程度极高的消化系肿瘤,其生长速度快、转移早,对放射和化学治疗不敏感.胰腺癌重要的病理特征是癌组织周围有大量以成纤维细胞、胶原和纤维黏连蛋白等结缔组织聚集.目前已有文献报道,活化的胰腺星状细胞在其中起着重要的作用:更有研究认为,胰腺星状细胞在胰腺癌的发生、发展和转移中亦可能起到一定的作用.本文就胰腺星状细胞和胰腺癌细胞之间的相互关系及其在胰腺癌发展和转移中的作用作一综述.     

Dangerous liaisons: pancreatic stellate cells and pancreatic cancer cells

One of the characteristic features of the majority of pancreatic ductal adenocarcinomas is an abundant desmoplastic/stromal reaction. Until recently, this stroma had received little attention from researchers studying the pathogenesis of pancreatic cancer, with most of the research focus resting on the biology of tumor cells themselves. However, evidence is now accumulating that the stroma plays a critical role in pancreatic cancer progression. The cells responsible for producing the stromal reaction in pancreatic cancer are activated pancreatic stellate cells (PSCs, the key effector cells in pancreatic fibrogenesis). In vitro and in vivo studies have convincingly demonstrated a close bi-directional interaction between PSCs and pancreatic cancer cells, which facilitates local tumor growth as well as distant metastasis. PSCs also interact closely with endothelial cells to stimulate angiogenesis and are possibly involved in the known resistance of pancreatic cancer to chemotherapy and radiation. Most interestingly, it has recently been shown that PSCs from the primary tumor can travel to distant metastatic sites where they likely facilitate the seeding, survival, and proliferation of cancer cells. Thus, it is now recognized that the stroma is an important alternative therapeutic target in this disease and concerted pre-clinical research is underway to develop strategies to modulate/deplete the stromal reaction to inhibit cancer progression. The challenge is to translate these developments into clinically applicable treatments for patients.     

Signal transduction in pancreatic stellate cells

Pancreatic fibrosis is a characteristic feature of chronic pancreatitis and of desmoplastic reaction associated with pancreatic cancer. For over a decade, there has been accumulating evidence that activated pancreatic stellate cells (PSCs) play a pivotal role in the development of pancreatic fibrosis in these pathological settings. In response to pancreatic injury or inflammation, quiescent PSCs undergo morphological and functional changes to become myofibroblast-like cells, which express α-smooth muscle actin (α-SMA). Activated PSCs actively proliferate, migrate, produce extracellular matrix (ECM) components, such as type I collagen, and express cytokines and chemokines. In addition, PSCs might play roles in local immune functions and angiogenesis in the pancreas. Following the initiation of activation, if the inflammation and injury are sustained or repeated, PSCs activation is perpetuated, leading to the development of pancreatic fibrosis. From this point of view, pancreatic fibrosis can be defined as pathological changes of ECM composition in the pancreas both in quantity and quality, resulting from perpetuated activation of PSCs. Because the activation and cell functions in PSCs are regulated by the dynamic but coordinated activation of intracellular signaling pathways, identification of signaling molecules that play a crucial role in PSCs activation is important for the development of anti-fibrosis therapy. Recent studies have identified key mediators of stimulatory and inhibitory signals. Signaling molecules, such as peroxisome proliferator-activated receptor-γ (PPAR-γ), Rho/Rho kinase, nuclear factor-κB (NF-κB), mitogen-activated protein (MAP) kinases, phosphatidylinositol 3 kinase (PI3K), Sma- and Mad-related proteins, and reactive oxygen species (ROS) might be candidates for the development of anti-fibrosis therapy targeting PSCs.     

Pancreatic stellate cells: Aiding and abetting pancreatic cancer progression

Tumour-stromal interactions have now been acknowledged to play a major role in pancreatic cancer (PC) progression. The abundant collagenous stroma is produced by a specific cell type in the pancreas-the pancreatic stellate cell (PSC). Pancreatic stellate cells (PSCs) are a unique resident cell type of pancreas and with a critical role in both healthy and diseased pancreas. Accumulating evidence indicates that PSCs interact closely with cancer cells as well as with other cell types of the stroma such as immune cells, endothelial cells and neuronal cells, to set up a growth permissive microenvironment for pancreatic tumours, which facilitates local tumour growth as well as distant metastasis. Consequently, recent work in the field has focused on the development of novel therapeutic approaches targeting the stroma to inhibit PC progression. Such a multi-pronged approach targeting both tumour and stromal elements of PC has been successfully applied in pre-clinical settings. The challenge now is to translate the pre-clinical findings into the clinical setting to achieve better outcomes for pancreatic cancer patients.     

Desmin-positive pancreatic stellate cells in human ontogenesis

Introduction: Although microcirculatory disturbances play pivotal role in the pathomechanism of acute pancreatitis (AP), very few papers can be found in which any of hemorheological parameters had been tested.The aim of our study was to analyze the hemorheological changes in cerulein-induced experimental acute pancreatitis in rat in two doses (5 and 10 μg/kg, s.c.), aiming to analyze the possible gender difference in hemorheological response, too.Methods: Male and female rats were subjected to     

胰腺星状细胞在胰腺癌组织中的激活及其可能作用

目的探讨胰腺星状细胞在胰腺癌组织中的表达及其可能作用.方法应用免疫组化观察24例胰腺癌、3例慢性胰腺炎胰腺组织a-平滑肌肌动蛋白(a-smooth muscle actin,a-SMA)和结蛋白(desmin)表达.结果24例胰腺癌、3例慢性胰腺炎胰腺组织a-平滑肌肌动蛋白均为阳性表达,且胰腺癌胰腺组织阳性染色均强于慢性胰腺炎胰腺组织.24例胰腺癌胰腺组织结蛋白阳性表达率为83.3%,而在3例慢性胰腺炎胰腺组织为0.结论胰腺星状细胞可能在胰腺癌的发生、发展中起一定作用.     

胰腺星状细胞在胰腺癌组织中的激活及其可能的作用

目的：探讨胰腺星状细胞在胰腺癌组织中的表达及其可能作用。方法：应用免疫组化观察24例胰腺癌、3例慢性胰腺炎胰腺组织α－平滑肌肌动蛋白（α-smooth muscle acitn,α-SMA）和结蛋白（desmin）表达。结果：24例胰腺癌、3例慢性胰腺炎胰腺组织α－平滑肌肌动蛋白均为阳性表达，且胰腺癌胰腺组织阳性染色均强于慢性胰腺炎胰腺组织。24例胰腺癌胰腺组织结蛋白阳性表达率为83．3％，而在3例慢性胰腺炎 胰腺组织为0。结论：胰腺星状细胞可能在胰腺癌的发生、发展中起一定作用。     

YAP activates pancreatic stellate cells and enhances pancreatic fibrosis

BackgroundPancreatic stellate cells (PSCs) foster the progression of pancreatic adenocarcinoma and chronic pancreatitis (CP) by producing a dense fibrotic stroma. However, the incomplete knowledge of PSCs biology hampers the exploration of antifibrotic therapies. Here, we explored the role of the Hippo pathway in the context of PSCs activation and experimental CP.MethodsCP model was created in rats with the tail vein injection of dibutyltin dichloride (DBTC). The expression of Yes-associated protein (YAP) in CP tissue was assessed. Primary and immortalized rats PSCs were treated with the YAP-inhibitor verteporfin. Furthermore, YAP siRNA was employed. Subsequently, DNA synthesis, cell survival, levels of α-smooth muscle actin (α-SMA) protein, presence of lipid droplets and PSCs gene expression were evaluated. Upstream regulators of YAP signaling were studied by reporter gene assays.ResultsIn DBTC-induced CP, pronounced expression of YAP in areas of tubular structures and periductal fibrosis was observed. Verteporfin diminished DNA replication in PSCs in a dose-dependent fashion. Knockdown of YAP reduced cell proliferation. Primary cultures of PSCs were characterized by a decrease of lipid droplets and increased synthesis of α-SMA protein. Both processes were not affected by verteporfin. At the non-cytotoxic concentration of 100 nmol/L, verteporfin significantly reduced mRNA levels of transforming growth factor-β1 (Tgf-β1) and Ccn family member 1 (Ccn1). YAP signaling was activated by TGF-β1, but repressed by interferon-γ.ConclusionsActivated YAP enhanced PSCs proliferation. The antifibrotic potential of Hippo pathway inhibitors warrants further investigation.     

Pancreatic stellate cells produce acetylcholine and may play a role in pancreatic exocrine secretion

The pancreatic secretagogue cholecystokinin (CCK) is widely thought to stimulate enzyme secretion by acinar cells indirectly via activation of the vagus nerve. We postulate an alternative pathway for CCK-induced pancreatic secretion. We hypothesize that neurally related pancreatic stellate cells (PSCs; located in close proximity to the basolateral aspect of acinar cells) play a regulatory role in pancreatic secretion by serving as an intermediate target for CCK and secreting the neurotransmitter acetylcholine (ACh), which, in turn, stimulates acinar enzyme secretion. To determine whether PSCs (i) exhibit CCK-dependent ACh secretion and (ii) influence acinar enzyme secretion, primary cultures of human and rat PSCs were used. Immunoblotting and/or immunofluorescence was used to detect choline acetyltransferase (ACh synthesizing enzyme), vesicular ACh transporter (VAChT), synaptophysin, and CCK receptors 1 and 2. Synaptic-like vesicles in PSCs were identified by EM. ACh secretion by PSCs exposed to 20 pM CCK was measured by LC-MS/MS. Amylase secretion by acini [pretreated with and without the muscarinic receptor antagonist atropine (10 μM) and cocultured with PSCs] was measured by colorimetry. PSCs express ACh synthesizing enzyme, VAChT, synaptophysin, and CCK receptors; exhibit CCK-dependent ACh secretion; and stimulate amylase secretion by acini, which is blocked by atropine. In conclusion, PSCs express the essential elements for ACh synthesis and secretion. CCK stimulates ACh secretion by PSCs, which, in turn, induces amylase secretion by acini. Therefore, PSCs may represent a previously unrecognized intrapancreatic pathway regulating CCK-induced pancreatic exocrine secretion.     

胰星状细胞对胰腺癌细胞株Patu8988侵袭和转移的影响

目的:探讨永生化人胰星状细胞(IPSC)对胰腺癌细胞株Patu8988侵袭和转移的影响.方法:制备IPSC上清,用IPSC上清和Patu8988共培养,以单独培养的Patu8988为对照,比较实验组与对照组细胞的增殖、黏附能力.侵袭、迁移能力,克隆形成以及抵抗H2O2诱导的Patu8988凋亡能力.结果:与单独培养的胰腺癌细胞株Patu8988相比,IPSC上清对胰腺癌细胞株Patu8988细胞的增殖、黏附、迁移、侵袭能力及克隆形成能力有促进作用(均p<0.05),并能抑制H2O2诱导的Patu8988的凋亡(P<0.05).结论:胰星状细胞可能通过增强胰腺癌细胞株Patu8988的增殖、黏附、迁移、侵袭能力及克隆形成能力,并抑制其的凋亡,在胰腺癌的发展和转移中起重要作用.     

Pancreatic stellate cells promote proliferation and invasiveness of human pancreatic cancer cells via galectin-3

AIM： To investigate the role of pancreatic stellate cells （PSCs） and galectin-3 （GAL-3） in the proliferation and infiltration of pancreatic cancer cell line SW1990. METHODS： Human pancreatic cancer cell line SW1990 and PSCs were cultured in vitro. Supernatant fluid of cultured PSCs and SW1990 cells was collected. Expression of GAL-3 in SW1990 cells and PSCs was detected by ELISA, RT-PCR and Western blotting. Proliferation of cultured PSCs and SW1990 cells was measured by 3-（4, 5-methylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） assay and flow cytometry. Infiltration of SW1990 cells was detected by a cell infiltration kit. RESULTS： SW1990 cells expressed GAL-3 and this was up-regulated by the supernatant fluid of cultured PSCs. PSCs did not express GAL-3. SW1990 cells stimulated proliferation of PSC,s via GAL-3. GAL-3 antibody inhibited SW1990 cell proliferation, while the supernatant fluid of PSCs stimulated proliferation of SW1990 cells through interaction with GAL-3 protein. The supernatant fluid of PSCs enhanced the invasiveness of SW1990 cells through interaction with GAL-3. CONCLUSION： GAL-3 and PSCs were involved in the proliferation and infiltration process of pancreatic cancer cells.     

胰腺星状细胞对胰腺癌AsPC-1细胞侵袭转移的影响

目的 探讨胰腺星状细胞(PSCs)对胰腺癌细胞侵袭转移的影响及基质细胞因子-I(SDF-1)在此过程中的作用.方法 常规分离、培养PSCs,收集及浓缩PSCs条件培养液(PSC-CM),应用不同浓度的PSC-CM、抗SDF-1抗体(anti-SDF-1)及两者联合应用处理AsPC-1细胞,采用MTT法检测AsPC-1细胞的增殖,Transwell小室检测细胞迁移,体外侵袭实验观察细胞侵袭能力.结果 对照组及0.25、0.5、1 μg/μl PSC-CM组AsPC-1细胞增殖的吸光度值(A490)分别为0.437 ±0.041、0.472±0.048、0.553±0.057、0.690±0.051,PSC-CM呈剂量依赖性促进细胞增殖,其中0.5、1μg/μl PSC-CM组与对照组间以及0.5 μg/μl与1μg/μl PSC-CM组间的差异具有统计学意义(P值均＜0.05).对照组、anti-SDF-1组、PSC-CM组及PSC-CM± anti-SDF-1组细胞增殖的A490值分别为0.407±0.028、0.416±0.030、0.629±0.048、0.481±0.049;穿膜细胞数分别为(35.3±7.1)、(34.8±5.6)、(140.9±12.7)、(56.5±5.9)个;侵袭细胞数分别为(27.1±2.9)、(29.1±4.2)、(81.5±8.2)、(46.4±4.4)个.anti-SDF-1组与对照组间的差异无统计学意义,PSC-CM组细胞的增殖、迁移、侵袭能力较对照组显著增强(P＜0.05或P＜0.01),PSC-CM± anti-SDF-1组细胞的增殖、迁移、侵袭能力较PSC-CM组显著降低,但仍显著高于对照组(P＜0.05或P＜0.01).结论 PSC-CM可促进AsPC-1的增殖、迁移及侵袭,其机制为部分通过SDF-1/CXCR4受体配体系统.     

胰腺星状细胞对血管内皮细胞增殖的影响

目的研究人胰腺星状细胞(PSC)在体内、外对血管内皮细胞增殖的影响。方法使用含10%小牛血清的M199培养基培养人脐静脉内皮细胞(HUVEC);含10%小牛血清的DMEM/F12细胞培养基培养PSC,检测前24 h换无血清培养基。逆转录-聚合酶链反应(RT-PCR)和Western印迹法检测血管内皮生长因子(VEGF)、白细胞介素(IL)-8和碱性纤维母细胞生长因子(bFGF)mRNA及蛋白在PSC中的表达,酶联免疫吸附试验检测PSC上清液中上述因子的含量;应用流式细胞技术和四甲基偶氮唑盐(MTT)比色法检测PSC上清液对HUVEC的增殖作用。同时,应用小管形成实验和鸡胚尿囊膜(CAM)模型研究PSC上清液对血管内皮细胞体内外血管生成的影响。结果PSC能独立合成并分泌VEGF、IL- 8及bFGF,流式细胞及MTT结果提示其上清液能使HUVEC的S期比例增加,有丝分裂增多。在体外血管形成研究中,PSC上清液能明显地促血管内皮细胞增殖并形成中空的管状结构;在体内CAM模型中,PSC上清液能使血管数目增加,管径增粗。结论PSC在体内外具有促血管生成作用。这一过程可能与其合成的VEGF、IL-8及bFGF等血管活性因子相关。PSC可能参与胰腺肿瘤的早期血行转移过程。