胃癌组织中P16蛋白的异常表达与临床病理学意义

目的:通过研究P16蛋白表达与胃癌发生及胃癌临床病理因素的关系,以探讨检测P16蛋白在胃癌诊断及判断胃癌恶性程度、估计预后和指导临床治疗的临床病理学意义.方法:采用免疫组化S-P法,检测100例胃癌与20例正常胃黏膜组织中P16蛋白表达情况.结果:P16蛋白在胃癌中表达率(36.0%)明显低于正常胃黏膜组织(85.0%)(P＜0.01);P16蛋白表达与肉眼类型、分化程度、浸润深度、淋巴结转移,TNM分期有关(P＜0.05);P16蛋白表达与患者性别、年龄、原发灶部位无关(P＞0.05).结论:检测P16蛋白的表达对辅助胃癌的诊断有很高的价值,并可作为判断胃癌恶性程度、估计预后和指导临床治疗的临床病理参考指标.     

低氘环境对胃癌细胞生长影响的体外实验

目的：研究低氘环境对人胃癌细胞（SGC-7901）增殖的影响并初步探讨其相关机制。方法：用含不同氘浓度的蒸馏水（实验组：25 ppm;对照组：150 ppm）配制的RPMI-1640培养基培养胃癌细胞SGC-7901。分别在不同的时间点对两组细胞的增殖率、细胞周期及凋亡情况进行检测,用Western blot法对两组细胞的增殖细胞核抗原蛋白（PCNA）的表达进行检测。结果：低氘环境下SGC-7901细胞的增殖率比对照组低10%左右。低氘环境对细胞的划痕愈合能力及集落形成能力也有显著抑制作用（P<0.05）。流式细胞术检测结果显示,与对照组相比,低氘组的细胞G1期细胞的比例增加（P<0.01）,而其所处S期细胞的比例下降（P<0.05）,两组细胞间早凋及晚凋比率差异无统计学意义。Western blot的结果显示低氘环境下培养的胃癌细胞的PCNA的表达明显下降。结论：低氘环境能够抑制胃癌细胞的生长,这可能与低氘环境下胃癌细胞阻滞于G1期及下调其PCNA的表达有关。     

Fas受体与FasL在胃癌细胞株的表达及意义

观察Fas受体与FasL在胃癌细胞株的表达,以及Fas和FasL的功能提供形态学依据。采用敏感的免疫组织化学SABC法,结果提示所有胃癌细胞均呈Fas受体免疫反应阳性,阳性物质定位于胸质,胞核为阴性反应;同样所有胃癌细胞亦呈FasL免疫反应性,阳性信号位于胞质,胞核未见阳性信号。这提示Fas可能参与了胃癌细胞生长的调节,胃癌细胞的凋亡在自我调控机制。     

口腔鳞癌组织细胞凋亡相关蛋白Fas/FasL的表达研究

目的　研究调亡相关蛋白Fas、FasL在口腔鳞状细胞癌组织中的表达及意义。方法　应用免疫组织化学方法检测 10例正常口腔粘膜、 38例口腔鳞癌组织及肿瘤浸润淋巴细胞 (TIL)和 11例转移淋巴结中Fas、FasL的表达。结果　Fas在正常口腔粘膜中广泛表达 ;鳞癌组织表达明显下调 (P <0 .0 5 ) ;Fas表达与口腔鳞癌分化程度有关 ;淋巴结转移癌中Fas表达减弱。FasL在正常口腔粘膜不表达 ;鳞癌组织表达明显上调 (P <0 .0 5 ) ;FasL表达与口腔鳞癌分化程度无关 (P >0 .0 5 ) ;有淋巴结转移者FasL阳性表达率高于无转移者 (P <0 .0 5 )。TIL细胞Fas、FasL阳性表达率为 81.6 %和 84 .2 % .。Fas、FasL在口腔鳞癌的表达有明显相关性 (P <0 .0 5 )。结论　Fas表达与口腔粘膜上皮细胞的自然分化成熟衰老及口腔鳞癌的形成和肿瘤的恶性度有关。FasL的表达上调可能是口腔鳞癌组织免疫反攻击的体现 ,对促进肿瘤的发生发展及转移有重要作用。     

癌变组织特异高表达抗凋亡蛋白——ARC

带有caspase富集功能域的凋亡抑制因子（ apoptosis repressor with a caspase recuitment domain, ARC ）是新近发现的重要抗凋亡蛋白。在正常组织中,ARC高度特异地表达在终末分化组织如心肌、骨骼肌和大脑,而在非终末分化组织不表达或微量表达。但是,当非终末分化组织发生癌变时表达大量的ARC。ARC过表达可以抑制阿霉素或射线诱导的癌细胞死亡,提示ARC在癌细胞中具有抗趋化或抗放射线损伤的作用。因此,ARC可能成为一种新的肿瘤标记物,也可能是决定肿瘤对各种治疗方法反应性的一个重要因素。     

硫氧还蛋白还原酶1(TrxR1)在胃癌中的表达及对胃癌细胞生长的影响

目的:探讨胃癌组织硫氧还蛋白还原酶1(TrxR1)表达与生存时间的关系及其对胃癌细胞生长的影响。方法:用Real-time PCR法检测76例胃癌组织及癌旁TrxR1 mRNA表达,并分析其与胃癌患者临床病理特征及预后的关系;随机选取3例胃癌组织及癌旁组织,采用免疫组化法、Western blot法检测TrxR1蛋白表达。采用Western blot法和Real-time PCR法检测胃癌细胞系及人胃粘膜上皮细胞中TrxR1的表达。采用小RNA干扰序列(siRNA)处理AGS细胞,根据处理方法不同将AGS细胞分为3组:阴性对照组:转染NC-siRNA、TRXR1 siRNA干扰1组:转染TRXR1-siRNA1、TRXR1 siRNA干扰2组:转染TRXR1-siRNA2。使用Real-time PCR法检测各组AGS细胞中TrxR1 mRNA的表达,克隆形成试验和MTT法检测AGS细胞生长情况。结果:胃癌组织中TrxR1 mRNA和蛋白表达量均显著性上调,TrxR1主要定位于细胞质中。TrxR1高表达与患者TNM分期及淋巴结转移有关,且TrxR1高表达组患者的中位生存时间短于低表达组...     

TGIF 对胃癌细胞生长和转移的影响

TGIF (TG-interacting factor) 是 TGF- β信号传导通路的抑制分子, 而 TGF-β早期抑制肿瘤生长,晚期促进肿瘤浸润与转移,但 TGIF 在肿瘤发生中的作用尚不清楚 . 将 TGIF 基因稳定转染胃癌细胞株 SGC-7901 ,采用 MTT 法、平板克隆形成试验、流式细胞术和裸鼠成瘤试验探讨 TGIF 对胃癌细胞生物学行为的影响,通过免疫组织化学分析裸鼠瘤组织基质金属蛋白酶 (matrix metallo proteinases, MMP) MMP2 、 MMP9 和血管内皮生长因子 (vascular eudothelial growth factor, VEGF) 的表达,通过 ELISA 和明胶酶谱试验分别分析 TGIF 转染细胞上清液中 VEGF 和活性 MMP2 与 MMP9 的含量变化 . TGIF 对 SGC-7901 细胞的生长、细胞周期分布和克隆形成率无影响 . TGIF 转染细胞接种裸鼠后无癌栓形成,但对照组有癌栓形成,且其瘤组织 MMP9 和 VEGF 的表达明显低于对照组,但 MMP2 在 3 组间的表达无差别 . TGIF 基因转染细胞、 PcDNA3.1 转染细胞和 SGC-7901 细胞上清液中 VEGF 的浓度分别为 (635 ± 20.3) ng/L 、 (780±25.4) ng/L 和 (791±23.9) ng/L , TGIF 转染细胞 VEGF 的含量明显低于对照组细胞 (P <0.01) , TGIF 转染细胞上清液中活性 MMP9 的含量明显低于对照组 . 尽管 TGIF 能部分拮抗 TGF-β1 介导的生长抑制和细胞周期阻滞作用,但它并不能使胃癌细胞的生物学行为恶化,相反 TGIF 通过下调 VEGF 和 MMP9 的表达降低胃癌细胞的浸润与转移能力 .     

辛伐他汀对动脉粥样硬化大鼠凋亡相关基因Fas及FasL蛋白表达的影响

目的通过研究辛伐他汀对动脉粥样硬化大鼠血管壁中细胞凋亡相关基因Fas及FasL蛋白表达产物的影响,探讨其在预防动脉粥样硬化发生中的可能机制。方法复制动脉粥样硬化大鼠模型,以辛伐他汀干预,取胸主动脉,观察其斑块变化,采用免疫组化Elivision法测定动脉粥样硬化血管壁中Fas、FasL蛋白表达。结果Fas蛋白表达在实验组明显高于对照组及干预组(P<0.01,P<0.05),实验组FasL蛋白表达也明显高于对照组及干预组(P<0.05)。结论Fas及FasL基因通过促进细胞凋亡作用而诱发动脉粥样硬化过程,辛伐他汀可通过调节细胞凋亡过程发挥抗动脉粥样硬化作用。     

乳腺浸润性导管癌组织中CAS蛋白表达的临床病理意义

目的研究乳腺浸润性导管癌组织中细胞凋亡易感蛋白（CAS）表达的临床病理意义。方法选取乳腺浸润性导管癌53例、普通导管增生20例、异型导管增生20例、导管原位癌10例、正常乳腺组织14例,应用免疫组化方法观察CAS蛋白的表达,并探讨CAS与乳腺癌临床病理因素的关系,分析CAS和HER2、ER、PR以及ki-67指数的关系。结果 CAS在正常乳腺、普通导管增生、异型导管增生、导管原位癌、浸润性导管癌中的阳性率逐渐升高,分别为14.3%、25.0%、40.0%、60%、75.5%（P=0.000）,CAS、HER2均与乳腺癌组织学分级、核分裂像、淋巴结转移有关;CAS评分与ki-67指数（r=0.439,P=0.003）和HER2评分（r=0.598,P=0.000）正相关。结论 CAS与乳腺癌的发生、发展、增殖、淋巴结转移有关,可能作为反映乳腺癌生物学行为的肿瘤标记物,CAS蛋白的表达和HER2有一定的相关性。     

九香虫血淋巴对肿瘤细胞凋亡相关蛋白表达的影响

探索九香虫血淋巴诱导肿瘤细胞凋亡的作用通路。利用Bradford法检测九香虫血淋巴浓度并将其作用于体外培养的人乳腺癌MCF-7细胞、人胃癌SGC-7901细胞,Western blot法检测经九香虫血淋巴干预后肿瘤细胞凋亡相关蛋白Caspase-3、Caspase-8、Caspase-9、Bcl-2、Bax等的表达。结果显示,九香虫血淋巴作用的SGC-7901、MCF-7细胞中Caspase-3、Caspase-9、Bax蛋白的表达较对照组细胞明显上调;两种细胞的Bcl-2蛋白,较对照组细胞表达明显下调;两种细胞的Caspase-8蛋白,较对照组细胞表达无明显差异。结果表明,经九香虫血淋巴诱导的SGC-7901、MCF-7细胞可能通过触发其线粒体凋亡途径使肿瘤细胞发生不可逆的凋亡。     

Matrix metalloproteinase 11 depletion inhibits cell proliferation in gastric cancer cells

Our previous study has shown that matrix metalloproteinase 11 (MMP11) is highly expressed in tumor cell lines and primary tumor of gastric cancer (GC). In order to reveal the correlation between expression of MMP11 and biological features of GC cell, we have constructed the recombinant plasmids producing hairpin small interfering RNA (siRNA) to target MMP11 mRNA using a vector-based RNA interference technology. Stable transfection of recombinants into GC cell line BGC823 specifically depleted the mRNA and protein of MMP11 as demonstrated by RT-PCR and Western blotting analysis. The siRNA-treated cells exhibited significantly decreased growth ability compared with mock transfectants and parental BGC823 cells. Furthermore, colony formation of MMP11 deficient cells was dramatically inhibited in soft agar and tumorigenicity was reduced in nude mice, respectively. These results provide new insights into the function of MMP11 and suggest that MMP11 may play an important role in the control of cell proliferation and tumor development in GC.     

热休克蛋白27在胃癌的表达及意义

目的探讨热休克蛋白27(HSP27)在胃癌及癌旁组织中的表达及其意义。方法用免疫组织化学法检测68例胃癌及57例癌旁组织中HSP27的表达,比较其阳性表达率。结果HSP27在胃癌中的表达率为47.1%,明显高于癌旁组织26.32%(P<0.05),并且与胃癌的分化程度相关,但与肌层浸润深度及淋巴结转移无关。结论HSP27在胃癌组织中过度表达,提示其在胃癌的发生发展中起着重要作用。     

The effects of PTBP3 silencing on the proliferation and differentiation of MKN45 human gastric cancer cells

Aims

PTBP3 overexpression inhibits the differentiation of leukemia cells; however, its effects on the differentiation and proliferation of solid cancer cells remain unclear. Thus, the impact of PTBP3 on the differentiation and proliferation of gastric cancer cells was investigated.

Main methods

PTBP3 expression was analyzed in normal and tumor tissues using immunohistochemistry. A xenograft model was established in nude mice by subcutaneous injection of untransfected human gastric cancer MKN45 cells or those expressing a control vector or PTBP3 siRNA. We analyzed the tumor inhibition rate, the expression of PTBP3, the PCNA-positive rate and the serum levels of CEA, CA199, CA125, LDH, ALP and γ-GT in different groups.

Key findings

The tumor weights in the PTBP3 siRNA group were significantly lower than that of the MKN45 cell control group (P < 0.001). Immunohistochemistry analysis of PCNA expression revealed that it was markedly reduced after PTBP3 silencing. ELISAs showed that the serum levels of CEA and CA199 tumor markers as well as LDH and ALP were reduced after PTBP3 silencing. Transmission electron microscopy revealed that MKN45 cells expressing PTBP3 siRNA had reduced nuclear-to-cytoplasmic ratio and regular nuclei, suggesting differentiation.

Significance

PTBP3 may promote proliferation and inhibit the differentiation of human gastric cancer MKN45 cells.     

LMP-1在胃癌和相应癌旁组织中的表达

目的探讨Epstein-Barr virus(EBV)感染与胃癌发生发展的关系。方法应用免疫组化SP法检测EB病毒潜伏感染膜蛋白-1(LMP-1)在97例胃癌组织及89例相应癌旁组织中表达。结果97例胃癌组织中30例LMP-1蛋白表达阳性,阳性率为30.9%,EBV阳性率与患者性别、浸润深度、淋巴结转移、组织学分型和临床分期之间无明显关系(P>0.05);89例相应癌旁组织中33例检测到EBV LMP-1的表达,胃癌组织及相应癌旁组织EBV阳性表达之间有显著相关性(P=0.000)。结论EBV感染与胃癌的发生有一定的相关性。     

Antibiotic drug tigecycline inhibited cell proliferation and induced autophagy in gastric cancer cells

Tigecycline acts as a glycylcycline class bacteriostatic agent, and actively resists a series of bacteria, specifically drug fast bacteria. However, accumulating evidence showed that tetracycline and their derivatives such as doxycycline and minocycline have anti-cancer properties, which are out of their broader antimicrobial activity. We found that tigecycline dramatically inhibited gastric cancer cell proliferation and provided an evidence that tigecycline induced autophagy but not apoptosis in human gastric cancer cells. Further experiments demonstrated that AMPK pathway was activated accompanied with the suppression of its downstream targets including mTOR and p70S6K, and ultimately induced cell autophagy and inhibited cell growth. So our data suggested that tigecycline might act as a candidate agent for pre-clinical evaluation in treatment of patients suffering from gastric cancer.     

miR-22 suppresses the proliferation and invasion of gastric cancer cells by inhibiting CD151

Gastric cancer (GC) is the second common cause of cancer-related death worldwide. microRNAs (miRNAs) play important roles in the carcinogenesis of GC. Here, we found that miR-22 was significantly decreased in GC tissue samples and cell lines. Ectopic overexpression of miR-22 remarkably suppressed cell proliferation and colony formation of GC cells. Moreover, overexpression of miR-22 significantly suppressed migration and invasion of GC cells. CD151 was found to be a target of miR-22. Furthermore, overexpression of CD151 significantly attenuated the tumor suppressive effect of miR-22. Taken together, miR-22 might suppress GC cells growth and motility partially by inhibiting CD151.     

Protein arginine methyltransferase 1 coordinates the epithelial-mesenchymal transition/proliferation dichotomy in gastric cancer cells

Protein arginine methyltransferase 1 (PRMT1) is up-regulated and promotes migration, invasion and proliferation in wide range of cancers. However, we for the first time identify that PRMT1 promotes migration and invasion and inhibits proliferation in gastric cancer cells, a phenomenon called “migration-proliferation dichotomy”. First, we find that PRMT1 overexpression promotes migration and invasion and inhibits proliferation, whereas PRMT1 knockdown reverses the above abilities. Next, PRMT1 reduces the expression of epithelial marker E-cadherin and increases the expression of mesenchymal markers including N-cadherin, Vimentin, snail and β-catenin in gastric cancer cells. Furthermore, our studies show that PRMT1 silencing promotes the phosphorylation of LATS1, and then induces YAP phosphorylation, while overexpression of PRMT1 down-regulates the phosphorylation of LATS1 and YAP, indicating that PRMT1 inhibits EMT probably via Hippo signaling. Collectively, the present study reveals important roles of PRMT1 in progression of gastric cancer. Given the dual functions of PRMT1, it is as a potential drug target of gastric cancer with extreme caution.     

球形幽门螺杆菌对SGC-7901细胞增殖的影响

目的:了解球形幽门螺杆菌对体外培养细胞增殖的影响.方法:采用抗生素诱导幽门螺杆菌标准菌株NCTC11637球变,将弯曲形和球形菌的菌悬液(1×108个/ml)作5倍梯度稀释,而后分别加入胃癌上皮细胞SGC-7901,共孵育3 d后,用MTT法检测SGC-7901细胞增殖的情况.结果:高浓度的弯曲形和球形幽门螺杆菌(＞8×107个/ml)可明显抑制细胞的增殖(P＜0.05);低浓度的球形幽门螺杆菌(＜1.28×105个/ml)可明显促进细胞的增殖(P＜0.05).结论:球形幽门螺杆菌在体外可影响SGC-7901细胞的增殖.     

Upregulation of MicroRNA-107 induces proliferation in human gastric cancer cells by targeting the transcription factor FOXO1

MicroRNA-107 (miR-107) has been demonstrated to regulate proliferation and apoptosis in many types of cancers. Nevertheless, its biological function in gastric cancer remains largely unexplored. Here, we found that the expression level of miR-107 was increased in gastric cancer in comparison with the adjacent normal tissues. The enforced expression of miR-107 was able to promote cell proliferation in NCI-N87 and AGS cells, while miR-107 antisense oligonucleotides (antisense miR-107) blocked cell proliferation. At the molecular level, our results further revealed that expression of FOXO1 was negatively regulated by miR-107. Therefore, the data reported here demonstrate that miR-107 is an important regulator in gastric cancer, which will contribute to a better understanding of the important mis-regulated miRNAs in gastric cancer.