肿瘤相关成纤维细胞通过分泌SDF-1α促进舌鳞癌细胞迁移及侵袭

目的：检测舌鳞癌组织中肿瘤相关成纤维细胞在舌癌迁移及侵袭过程中的作用。方法：体外原代培养舌鳞癌组织肿瘤相关成纤维细胞,收集其培养上清作用于舌鳞癌细胞系Tca8113,检测肿瘤细胞迁移及侵袭。利用实时定量PCR检测其的SDF—1αmRNA表达水平。利用SDF-1α受体CXCR4特异性阻断剂探SDF-1α在此过程的作用。结果：肿瘤相关成纤维细胞可明显促进Tca8113的迁移及侵袭。同时,利用实时定量PCR检测发现肿瘤相关成纤维细胞较正常人皮肤来源成纤维细胞SDF-1α表达水平明显升高。AMD3100,SDF-1α受体CXCR4特异性阻断剂,可显著抑制肿瘤相关成纤维细胞条件培养基对Tca8113迁移能力的促进作用。结论：舌鳞癌组织中的肿瘤成纤维细胞可通过分泌SDF-1α促进舌鳞癌细胞的迁移及侵袭,可能在肿瘤发展过程发挥重要作用。     

肿瘤相关成纤维细胞促进舌鳞癌细胞上皮间质转化

目的：检测舌鳞癌组织中肿瘤相关成纤维细胞是否诱导舌癌细胞的上皮间质转化。方法：通过体外原代培养舌鳞癌组织肿瘤相关成纤维细胞的培养上清作用于舌鳞癌细胞系Tca8113,通过检测细胞形态确认肿瘤细胞是否发生上皮间质转化。利用实时定量PCR及免疫印迹检测舌鳞癌细胞上皮标志及间质标志物表达。利用TGF-β/Smad信号通路阻断剂探究TGF-β在此过程的作用。结果：肿瘤相关成纤维细胞促进Tca8113的上皮间质转化。利用实时定量PCR检测及免疫印迹发现肿瘤相关成纤维细胞可以明显促进Tca8113细胞的Vimentin的表达。SB431542,TGF-β/Smad信号通路特异性阻断剂可明显阻断肿瘤相关成纤维细胞条件培养基对Tca8113上皮间质转化的诱导作用。结论：舌鳞癌组织中的肿瘤成纤维细胞可通过诱导舌鳞癌细胞的上皮间质转化促进舌鳞癌细胞的迁移及侵袭,可能在肿瘤发展过程发挥重要作用。     

成纤维细胞活化蛋白及其对肿瘤——宿主界面基质的降解和重建作用研究

成纤维细胞活化蛋白(FAP)是癌相关成纤维细胞的标志性产物之一,具有特殊的结构和生物学特性,在肿瘤—宿主界面基质的降解和重建中发挥重要作用,对肿瘤的浸润、转移及逆转具有重要意义。针对FAP进行干预为肿瘤生物学治疗提供了新的途径。     

癌相关成纤维细胞促口腔鳞状细胞癌侵袭转移的研究进展

癌相关成纤维细胞是口腔鳞状细胞癌间质中的主要成分,与肿瘤患者的预后息息相关。癌相关成纤维细胞自分泌和旁分泌信号蛋白,直接或间接作用于肿瘤微环境,调控肿瘤的发生、发展、侵袭和转移。目前,癌相关成纤维细胞促口腔鳞状细胞癌侵袭转移的机制包括细胞外基质改建、生长因子及趋化因子的分泌、上皮-间质转化、免疫抑制和血管新生等,本文对此作-综述。     

肿瘤相关成纤维细胞与内皮细胞交互作用的研究进展

在肿瘤-宿主界面微环境中的成纤维细胞和内皮细胞具有独特的生物学特性和功能,二者通过直接接触和细胞间生物信号交流产生复杂的交互作用,在肿瘤微血管的形成和发展、肿瘤生长、侵袭等过程中扮演重要角色。对二者交互作用的研究为探索肿瘤防治新靶标提供了理论依据。本文对肿瘤相关成纤维细胞与内皮细胞交互作用的研究进展进行综述。     

癌相关成纤维细胞与口腔癌关系的研究进展

上皮组织与间质通过复杂而精细的网络系统构成一个平衡的微生态体系,当各种因素导致恶性肿瘤发生时,原有的微生态平衡被打破,变异上皮及其邻近宿主间质会构成新的微生态体系.间质细胞与细胞外基质(extracellular matrix,ECM)构成的肿瘤-宿主界面微环境在肿瘤的发生、发展过程中扮演着重要角色.肿瘤细胞的微环境不同于正常间质,称为"反应性间质",表现为:ECM成分改变、微血管密度增加、炎症细胞数量增多和出现活化的成纤维细胞[1-2].这些活化的成纤维细胞被称为癌相关成纤维细胞(carcinoma-associated fibrohlasts,CAF).在对不同类型的恶性肿瘤研究中发现,CAF在一定程度上决定上皮细胞的命运,可以促进上皮细胞的侵袭和转移[3-6].     

口腔癌相关成纤维细胞的研究进展

间质细胞与细胞外基质构成的肿瘤-宿主界面微环境对肿瘤细胞的生长、浸润和转移具有重要作用。其中,癌相关成纤维细胞是最重要的宿主细胞,对口腔癌的发生发展起着重要的作用,以其为靶标所进行的肿瘤间质治疗开拓了肿瘤防治新途径。下面就癌相关成纤维细胞及其来源、与口腔癌的关系和治疗作一综述。     

用原代培养方法建立炎症性牙龈和牙周膜组织细胞有限细胞系

体外培养方法、培养条件、病例标本来源的特殊性、细胞种类及实验技巧等均影响各自原代细胞培养的成功率,同时也是限制了很多研究的原因之一.虽然已有报道尝试通过克隆杂交、基因转染技术建成体外无限细胞系,但不可避免地含有部分肿瘤样细胞的特性,其结果的参考价值受到影响.临床健康者来源的牙龈和牙周膜成纤维细胞培养方法已有介绍且成功率较高[1～4],但炎性病变时牙龈和牙周组织的表现和反应至今未见专门报道.作者结合有关炎症牙周组织成纤维细胞体外培养实验报道[5～7],将培养牙周炎症组织原代成纤维细胞的方法介绍如下.     

牙髓成纤维细胞的免疫相关作用研究进展

成纤维细胞作为牙髓的主要细胞,其基本功能是合成胶原和基质.近年的研究表明成纤维细胞在牙髓免疫炎症反应中发挥着重要作用.本文从成纤维细胞产生炎症介质、合成生长因子等几个方面对其免疫相关作用作一综述.     

体外培养人牙周牙髓相关细胞中釉原蛋白的表达

目的:观察釉原蛋白(amelogenin,Am)基因在体外培养的人牙龈上皮细胞及口腔外胚间充质来源细胞(人牙龈成纤维细胞、人牙周膜成纤维细胞和人牙髓细胞)中的表达.方法:采用反转录多聚酶链式反应(RT-PCR)技术,检测培养细胞中釉原蛋白mRNA的表达.采用蛋白质免疫印迹技术检测培养细胞中釉原蛋白的表达.结果:培养的人牙周膜成纤维细胞、牙髓细胞、牙龈成纤维细胞和牙龈上皮细胞中均未检测到釉原蛋白及其mRNA的表达.结论:体外培养的人牙周膜成纤维细胞、牙髓细胞、牙龈成纤维细胞和牙龈上皮细胞不表达釉原蛋白基因.     

Genetic regulation and potentially therapeutic application of cancer‐associated fibroblasts in oral cancer

Carcinoma‐associated fibroblast (CAF) is the most important host cell type in tumor microenvironment, which greatly contributes to tumor initiation, progression, and metastasis. Therefore, a large amount of data has emerged, showing the cancer‐promoting function of these cells via paracrine effects that escort tumor cells through all the steps of cancer development. CAF is a heterogeneous cell population that can arise from the differentiation of resting fibroblasts, epithelial cells, endothelial cells, and mesenchymal stem cells. This review summarizes the current knowledge of the role of CAFs in tumor progression, with a particular focus on the cellular and molecular features and recent advances in researches on the genetic status and microRNA regulation, and addresses the potential prognostic and therapeutic values for patients with oral cancer by targeting CAFs.     

Regulation of cellular communication network factor 2 (CCN2) in breast cancer cells via the cell-type dependent interplay between CCN2 and glycolysis

ObjectivesAnti-osteoclastic treatments for breast cancer occasionally cause medication-related osteonecrosis of the jaw. Moreover, elevated glycolytic activity, which is known as the Warburg effect, is usually observed in these breast cancer cells. Previously, we found that cellular communication network factor 2 (CCN2) production and glycolysis enhanced each other in chondrocytes. Here, we evaluated the interplay between CCN2 and glycolysis in breast cancer cells, as we suspected a possible involvement of CCN2 in the Warburg effect in highly invasive breast cancer cells.MethodsTwo human breast cancer cell lines with a distinct phenotype were used. Glycolysis was inhibited by using 2 distinct compounds, and gene silencing was performed using siRNA. Glycolysis and the expression of relevant genes were monitored via colorimetric assays and quantitative RT-PCR, respectively.ResultsAlthough CCN2 expression was almost completely silenced when treating invasive breast cancer cells with a siRNA cocktail against CCN2, glycolytic activity was not affected. Notably, the expression of glycolytic enzyme genes, which was repressed by CCN2 deficiency in chondrocytes, tended to increase upon CCN2 silencing in breast cancer cells. Inhibition of glycolysis, which resulted in the repression of CCN2 expression in chondrocytic cells, did not alter or strongly enhanced CCN2 expression in the invasive and non-invasive breast cancer cells, respectively.ConclusionsHigh CCN2 expression levels play a critical role in the invasion and metastasis of breast cancer. Thus, a collapse in the intrinsic repressive machinery of CCN2 due to glycolysis may induce the acquisition of an invasive phenotype in breast cancer cells.     

Inhibition of acid production from oral bacteria by fluorapatite-derived fluoride

The inhibitory effect of fluorapatite (FAP)-derived fluoride upon resting cell suspensions of Streptococcus mutans incubated at pH 4.5 and 6.5 was studied using lactic acid production from 0.1% sucrose as an indicator of fermentation activity. Cells incubated with FAP produced significantly less lactic acid than did cells incubated with hydroxyapatite (HAP). Addition of HAP to cell suspensions containing FAP reduced this inhibition, suggesting that dissolution of the FAP was necessary for inhibition. Incubation with low concentrations of NaF showed significant inhibition in cell suspensions incubated with as little as 0.45 micrograms/mL F at pH 5.0. These results provide further support to the hypothesis that fluoride levels in plaque and enamel, achievable through use of fluoridated water and/or fluoride dentifrices, may produce appreciable inhibition of glycolysis at the acidic pH levels which are readily achieved in plaque. Thus, bacterial acid production may activate plaque and enamel-bound fluoride, resulting in inhibition of further acid production, and thereby contribute substantially to the other cariostatic mechanisms of fluoride.     

Curcumin suppresses the proliferation and tumorigenicity of Cal27 by modulating cancer‐associated fibroblasts of TSCC

Cancer‐associated fibroblasts (CAFs) are “activated” fibroblasts in the tumor microenvironment (TME) and play a vital role in all steps of cancer development. Increasing evidence focusing on the function of CAFs suggests that CAFs are candidate therapeutic targets and that drugs targeting the modification of CAFs would suppress tumor progression and be beneficial to tumor treatment and prevention. In the present study, we found that curcumin reversed the phenotype of CAFs to that of peri‐tumor fibroblast (PTF)‐like cells by downregulating the expression of α‐SMA (a special marker for CAFs) and inhibiting the secretion of pro‐carcinogenic cytokines, including transforming growth factor‐β1 (TGF‐β1), matrix metalloproteinases 2 (MMP2), and stromal cell‐derived factor‐1 (SDF‐1). We further demonstrated that the conditioned medium (CM) derived from CAFs promoted the proliferation of Cal27, and this effect was confirmed by the xenograft model. More importantly, we found that curcumin blocked the CAF‐mediated enhancement of Cal27 proliferation in vitro and in vivo. In conclusion, our data suggest that curcumin reverses cell phenotype from CAF to PTF‐like cells and suppresses the CAF‐mediated proliferation and tumorigenicity of Cal27 by inhibiting TSCC CAFs.     

Biochemical mechanisms of enhanced inhibition of fluoride on the anaerobic sugar metabolism by Streptococcus sanguis

The effect of fluoride on acid production by Streptococcus sanguis ATCC 10556 was compared under anaerobic and aerobic conditions. The rate of acid production under constant-pH and pH-free-fall conditions was determined during glucose metabolism by resting cells. Anaerobic glycolysis was inhibited more strongly by fluoride than was aerobic glycolysis. Intracellular levels of 3-phosphoglyceric, 2-phosphoglyceric, and phosphoenolpyruvic acids were lower under anaerobic conditions than under aerobic conditions. Thus, S. sanguis had a low phosphoenolpyruvate (PEP) potential under anaerobic conditions. This low PEP potential was suggested to account for the more effective fluoride inhibition of enolase and, consequently, the reduced transport of sugar by the PEP-dependent phosphotransferase system of this micro-organism.     

Effect of salivary supernatant on the glycolytic activity of the bacteria in salivary sediment

The salivary supernatant of the suspended salivary sediment (SSS) system stimulates the glycolytic activity of the sediment bacteria under aerobic conditions. Evidence for such glycolytic stimulation in the experiments carried out at low glucose concentration was a more rapid utilization of glucose and a more rapid rise and fall in the concentration of lactic acid. Although supernatant enhanced glycolysis, after a 4-hr incubation those sediment mixtures without supernatant contained more acid and showed a much larger decrease in the pH than those mixtures with supernatant. At high glucose concentration the amount of glucose catabolized and the amount of total acid formed were much greater in those mixtures containing supernatant. The decrease in pH, however, was approximately the same. The smaller pH fall with low glucose and the almost equal fall with high glucose indicate that in the presence of supernatant there is increased base formation counteracting the enhanced glycolysis. With low glucose concentrations, the extent of the pH fall was dependent upon the supernatant concentration, whereas at high glucose concentration it was not.     

Mechanism of inhibition of glycolysis in Streptococcus mutans NCIB 11723 by chlorhexidine

Inhibition of the rate of acid production from glucose by the cells of Streptococcus mutans was directly related to the concentrations of 0.075 to 0.20 mM chlorhexidine. Lactate production was inhibited to a greater extent than acetate and formate. Quantification of glycolytic intermediates revealed that the steps in glycolysis inhibited by chlorhexidine were the reactions catalyzed by phosphofructokinase and glyceraldehyde 3-phosphate dehydrogenase and/or phosphoglycerate kinase. However, the activities of these enzymes were not decreased in cells treated with the inhibitor. It was demonstrated that chlorhexidine caused leakage of metabolites from the cells. Our results indicate that the decreased rate of glycolysis caused by chlorhexidine is due to the leakage of metabolic intermediates and not to direct effects on enzymes involved in glycolysis by S. mutans NCIB 11723.     

The time-course of acid excretion, levels of fluorescence dependent on cellular nicotinamide adenine nucleotide and glycolytic intermediates of Streptococcus mutans cells exposed and not exposed to air in the presence of glucose and sorbitol

The aim of this study was to examine glucose and sorbitol metabolism in Streptococcus mutans cells exposed and not exposed to air at the coexistence of these compounds by measuring acid excretion, levels of fluorescence dependent on cellular NADH and glycolytic intermediates. An aliquot of bacterial cells grown under strictly anaerobic conditions (anaerobic cells) was exposed temporarily to air (aerobic cells). When glucose was added to the anaerobic cells metabolizing sorbitol, the acid excretion was increased. The level of NADH decreased initially and then increased to the higher plateau level than that during glucose metabolism. The aerobic cells neither metabolized sorbitol nor contained glycolytic intermediates. However, 2 min after glucose was added in the presence of sorbitol, the acid excretion was started slowly and the intermediates appeared. The level of NADH was decreased at first and then increased. These results suggested that the anaerobic S. mutans cells metabolized glucose and sorbitol simultaneously, and that in the presence of sorbitol the aerobic cells could start to metabolize glucose 2 min after glucose was added, as the intermediates (phosphoenopyruvate potential) for the glucose transport were accumulated.     

Dehydrogenase histochemistry of the rat molar pulp

Activity of various dehydrogenases was studied histochemically in fully developed, functional Sprague-Dawley rat molar pulps using a method of demineralization that conserves substantial enzyme activity. Odontoblasts, cells of the subodontoblastic cell-rich zone, other connective tissue cells of the pulp and cells of blood vessels and nerves showed varying degrees of activity for succinic, malic, isocitric, glutamic, lactic, -glycerophosphate, β-hydroxybutyric, glucose-6-phosphate, NADH₂and NADPH₂- dehydrogenases. Especially marked reactions were noted in odontoblasts and cells of the sub-odontoblastic zone.

From these results it can be inferred that the cells of the pulp possess the capacity for glycolysis and fatty acid metabolism, and also a functional citric acid cycle and pentose shunt.