miR-99b通过下调mTOR的表达抑制胃腺癌细胞系SGC-7901的增殖及迁移

目的:探讨hsa-miR-99b在胃腺癌细胞系的表达及其影响胃腺癌细胞系增殖和迁移的潜在作用机制.方法:Real-time PCR检测miR-99b在人胃上皮细胞系GES-1和人胃腺癌细胞系SGC-7901、BGC-823、MGC-803中的表达.用人工合成的miR-99b模拟物转染SGC-7901细胞构建过表达miR-996细胞系,转染对照模拟物作为对照组,CCK-8法检测过表达miR-99b的SGC-7901细胞的增殖情况,Transwell法检测SGC-7901细胞系的迁移情况,Western blotting检测SGC-7901细胞系中哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)的表达情况.结果:miR-99b在胃腺癌细胞系中的表达水平显著低于胃上皮细胞系,其中以SCG-7901细胞最甚.转染miR-99b模拟物48 h后,实验组SCG-7901细胞增殖能力低于对照组(0.20±0.00 vs 0.27±0.02,P＜0.05);与转染对照模拟物的细胞相比,转染24 h后,实验组SCG-7901穿膜细胞数低于对照组[(226.67 ±25.17) vs (523.33±25.17)个,P＜0.05].miR-99b可下调人胃腺癌细胞系SGC-7901中mTOR蛋白的表达.结论:miR-99b在胃腺癌细胞系中的表达明显下调,miR-99b抑制人胃腺癌细胞系SGC-7901增殖和迁移的作用可能与下调mTOR表达有关.     

PIK3CA过表达对胃癌细胞侵袭力影响的探讨

目的:探讨PIK3CA过表达对胃癌细胞侵袭力的影响.方法:采用RT-PCR和蛋白质印迹法分别检测3种不同分化胃癌细胞HGC-27、BDC-823和SGC-7901中PIK3CA mRNA及蛋白表达水平.通过Transwell侵袭小室法检测其侵袭力,分析PTK3CA表达水平变化对胃癌细胞侵袭力的影响.结果:PIK3CAmRNA及蛋白在未分化HGC-27细胞中表达水平最高,细胞侵袭力最强(穿膜细胞数为45.24±3.16),在低分化BGC-823细胞(穿膜细胞数为22.28±1.65)及中等分化的SGC-7901细胞(穿膜细胞数为14.42±1.02)中分别次之(P<0.05).结论:PIK3CA mRNA及蛋白表达水平越高,细胞侵袭力越强,且后者随前者表达减少而减弱;PIK3CA过表达可能在胃癌细胞侵袭中起重要作用.     

4-1BB基因在不同分化胃癌细胞株中的表达

目的：研究共刺激因子4-1BB在人胃高分化腺癌细胞株MKN-28、人胃中分化腺癌细胞株SGC-7901、人胃低分化腺癌细胞株BGC-823、人胃粘液腺癌细胞株MGC-803中的表达及其生物学意义。方法：用RT-PCR法测定胃癌细胞株中4-1BB mRNA表达;免疫细胞化学法测定胃癌细胞株中4-1BB蛋白表达;MTT法测定人淋巴细胞对胃癌细胞的体外杀伤活性;ELISA法检测人淋巴细胞与胃癌细胞共培养上清液中IL-2、IL-10、TNF-α的含量。结果：RT-PCR结果示4-1BB mRNA表达率从高到低依次为：MGC-803（77.30%）、BGC-823（71.68%）、SGC-7901（40.06%）、MKN-28（37.65%）。免疫细胞化学结果显示4-1BB着色程度由深到浅依次为：MGC-803、BGC-823、SGC-7901、MKN-28。MTT结果显示各时间段（24、48、72h）不同效靶比（10∶1,20∶1,40,∶1）下,人淋巴细胞对胃癌细胞的体外杀伤活性由高到低的顺序为：MKN-28、SGC-7901、BGC-823、MGC-803。ELISA结果显示在各效靶细胞比下,人淋巴细胞与胃癌细胞共培养上清液中IL-2、TNF-α的含量由高到低的顺序均为：MKN-28、SGC-7901、BGC-823、MGC-803。而IL-10的含量由高到低的顺序为：MGC-803、BGC-823、SGC-7901、MKN-28。结论：人胃癌细胞株MKN-28、SGC-7901、BGC-823、MGC-803中4-1BB基因的mRNA和蛋白均有表达,且胃癌细胞株的恶性程度越高其4-1BB表达水平越高;淋巴细胞对低表达4-1BB胃癌细胞的杀伤力较高;提示4-1BB可能通过抑制细胞因子TNF-α、IL-2和促进细胞因子IL-10的产生调节肿瘤免疫。     

lncRNA 00707 通过miR-613 调控胃癌MGC-803、SGC-7901 细胞的恶性生物学行为

[摘要] 目的:探讨长链非编码RNA 00707（lncRNA 00707）和微小RNA-613(miR-613)对胃癌细胞增殖和转移的调控作用及其相关机制。方法：收集2014 年1 月至2018 年6 月青海省人民医院肿瘤外科89 例原发性胃癌组织及癌旁组织标本以及胃癌MGC-803、SGC-790、BGC-823 细胞,采用qPCR实验检测胃癌组织和细胞系中lncRNA 00707、miR-613 的表达水平。分别建立lncRNA00707 低表达和过表达细胞模型,采用CCK-8 实验检测MGC-803、SGC-7901 细胞增殖能力,Transwell 法检测MGC-803、SGC-7901 细胞迁移和侵袭能力。用双荧光素酶基因报告实验验证lncRNA 00707 与miR-613 的靶向关系。结果：与癌旁组织相比,胃癌组织中lncRNA 00707 呈明显高表达(P<0.01),lncRNA 00707 表达水平与WHO分期呈正相关(P<0.05);与正常细胞系GES-1 相比,胃癌细胞系中lncRNA 00707 表达明显上调(P<0.05)。敲低lncRNA 00707 可明显抑制SGC-7901 细胞的增殖、侵袭和迁移能力(均P<0.05);lncRNA 00707 过表达可明显提高MGC-803 细胞的增殖和迁移能力(P<0.05)。与阴性对照组相比,lncRNA00707 过表达显著降低了miR-613 荧光素酶报告载体的荧光素酶活性,而下调MGC-803 和SCG-7901 细胞中lncRNA 00707,miR-613 的表达显著增加（均P＜0.01）。结论：lncRNA 00707 在胃癌组织和细胞系中发挥促癌效应,其可以通过抑制miR-613 而促进胃癌MGC-803 和SCG-7901细胞的增殖和转移。     

香加皮杠柳苷联用TRAIL对胃癌SGC-7901和MGC-803细胞的作用及其机制

目的:探讨香加皮杠柳苷(cortex periplocae,CPP)联用肿瘤坏死因子相关凋亡诱导配体(tumor necrosis factor related apoptosis inducing ligand,TRAIL)对胃癌细胞的作用及其机制.方法:人胃癌细胞系SGC-7901、MGC-803培养完成后,采用50、100、200 ng/ml的CPP和1μg/ml的TRAIL单用或联合处理.MTS法检测SGC-7901和MGC-803细胞的增殖情况,流式细胞术检测其凋亡率,Westcm boltting检测pro-BID、Mcl-l、cleaved caspase-3、DR4、DR5的表达水平.结果:SGC-7901和MGC-803细胞经CPP (50、100、200 ng/ml)和TRAIL(1 μg/ml)联合处理24 h后,细胞增殖率明显低于空白对照组和对应的CPP各剂量单独处理组(/＜0.05或P＜0.01).SGC-7901和MGC-803细胞凋亡率均明显高于空白对照组和对应的CPP各剂量单独处理组(P＜0.05或P＜0.01).SGC-7901和MGC-803细胞中pro-BID、Mcl-1表达水平明显降低(均P＜0.05),cleaved caspase-3表达水平明显升高(P＜0.05),DR4和DR5受体的表达水平升高(均P＜0.05).结论:CPP协同TRAIL可明显诱导人胃癌SGC-7901和MGC-803细胞凋亡,增强人胃癌细胞对TRAIL的敏感性.     

miR-1271-5p在胃癌组织的表达及对胃癌AGS细胞生物学行为的影响

目的 探讨miR-1271-5p在胃癌组织和细胞中的表达及其对胃癌细胞增殖、侵袭和迁移的影响。方法 收集2011年6月至2014年6月广西医科大学附属肿瘤医院90例手术切除胃癌组织及相应癌旁组织。采用qRT-PCR法检测胃癌组织及相应癌旁组织,人胃癌细胞系（SGC-7901、MGC-803、AGS）和人正常胃黏膜上皮细胞系GES1中miR-1271-5p的表达情况。利用瞬时转染法将miR-1271-5p mimics（过表达miR-1271-5p组）和miR-NC（阴性对照组）分别转染胃癌AGS细胞,建立过表达miR-1271-5p的胃癌AGS细胞系,然后采用CCK-8法检测转染后的胃癌AGS细胞增殖能力,平板克隆形成实验检测细胞克隆形成能力,Transwell实验检测细胞迁移和侵袭能力。结果 miR-1271-5p在胃癌组织和胃癌细胞（SGC-7901、MGC-803、AGS）中的表达均低于相应癌旁组织及人正常胃黏膜上皮GES1细胞（均P<0.01）。与阴性对照组相比,过表达miR-1271-5p组胃癌AGS细胞增殖活力降低（P<0.01）,细胞集落形成数减少（P<0.01）,迁移和侵袭细胞数量亦减少（P<0.01）。结论 miR-1271-5p在胃癌组织和细胞中低表达,上调miR-1271-5p可抑制胃癌AGS细胞的增殖、迁移和侵袭。     

胃癌细胞外泌体调控M2型巨噬细胞极化及对胃癌细胞增殖和迁移的影响

目的:探究胃癌细胞外泌体调控M2型巨噬细胞极化及对胃癌细胞增殖和迁移能力的影响。方法:差速离心法提取胃黏膜上皮细胞GES-1和胃癌细胞株MGC-803、SGC-7901外泌体,透射电镜和Western blot鉴定外泌体,将U937细胞与PMA共孵育诱导U937细胞分化为巨噬细胞的同时分别与PBS、GES-1 exo、MGC-803 exo、SGC-7901 exo、IL-4孵育48 h,流式细胞术检测孵育后各组细胞CD206和HLA-DR表达,qRT-PCR检测CCL17、CXCL8、IL-10、TGF-β、TNF-α、IL-6、IL-1β表达,Western blot检测p-NF-κB、NF-κB、IκBα表达水平,将各组诱导后的U937细胞与MGC-803、SGC-7901共培养后,收集MGC-803、SGC-7901细胞,MTT检测各组细胞的增殖能力,Transwell小室法检测各组细胞的迁移能力。结果:差速离心法提取的外泌体符合外泌体的形态特征,并且在激光共聚焦显微镜下观察到外泌体可被U937细胞摄取,与MGC-803 exo、SGC-7901 exo共孵育后的U937细胞CD206显著高表达,HLA-DR低表达（P＜0.05）,CCL17、CXCL8、IL-10、TGF-β表达显著上调（P＜0.05）,TNF-α、IL-6、IL-1β表达显著下调（P＜0.05）,NF-κB磷酸化水平显著增加（P＜0.05）,IκBα表达显著增加（P＜0.05）,并且与MGC-803 exo、SGC-7901 exo诱导极化后的巨噬细胞共培养组MGC-803、SGC-7901细胞增殖和迁移能力显著增强（P＜0.05）。结论:胃癌细胞能够通过激活NF-κB信号通路促进M2型巨噬细胞极化进而诱导MGC-803、SGC-7901细胞增殖和迁移能力的增强。     

miR-325-3p靶向CLDN1基因调控胃癌上皮间质转化和侵袭转移

目的 探讨miR-325-3p靶向CLDN1基因对胃癌上皮间质转化和侵袭转移的影响。方法 选取人胃黏膜上皮细胞株GES-1以及人胃癌细胞株HGC27、SGC-7901、MKN-45和MGC-803,并检测细胞中miR-325-3p和CLDN1的表达。双荧光素酶报告实验验证miR-325-3p和CLDN1的靶向关系,干预胃癌细胞中miR-325-3p和CLDN1的表达,qRT-PCR和Western blot检测细胞中N-cadherin、Vimentin和MMP2的表达,CCK-8检测细胞增殖活力,Transwell和流式细胞仪分别检测细胞侵袭和凋亡能力。结果 相对于GES-1细胞,MGC-803细胞中miR-325-3p表达降低而CLDN1表达增高（均P<0.05）,双荧光素酶报告实验证实CLDN1为miR-325-3p的靶基因。过表达miR-325-3p能够抑制胃癌细胞的增殖、侵袭和上皮间质转化,促进胃癌细胞凋亡,抑制miR-325-3p则能够促进胃癌细胞的增殖、侵袭和上皮间质转化,抑制胃癌细胞凋亡（均P<0.05）。而过表达CLDN1则能够逆转miR-325-3p过表达对胃癌细胞生物学行为的影响。结论 miR-325-3p能够靶向抑制CLDN1进而抑制胃癌细胞的侵袭转移和上皮间质转化,促进胃癌细胞凋亡,miR-325-3p有望成为治疗胃癌的新靶点。     

miR-361-5p通过靶向CCND1逆转胃癌SGC-7901细胞奥沙利铂耐药性

目的:探讨miR-361-5p对胃癌SGC-7901细胞奥沙利铂(oxaliplatin,OXA)耐药性的影响及其作用机制.方法:采用qPCR法检测miR-361-5p在胃癌细胞MKN-45、MGC80-3、SGC-7901和OXA耐药细胞SGC-7901/OXA中的表达水平.利用脂质体转染技术分别将miR-361-5...     

PTEN在胃癌细胞中的表达及其CpG岛甲基化状态的研究

目的检测抑癌基因PTEN在四种胃癌细胞中mRNA和蛋白表达水平及其5’启动子区CpG岛甲基化状态。方法采用甲基化特异性聚合酶链反应(Methylation-specific PCR,MSP)检测四种不同分化程度的胃癌细胞(HGC-27,MGC-803,BGC-823,SGC-7901)中PTEN基因启动子区域甲基化状态,RT-PCR和Westernblot法分别检测其mRNA和蛋白表达水平。结果除SGC-7901外,其他三种细胞可检测到PTEN基因启动子的甲基化。PTENmRNA和蛋白表达水平依次为:SGC-7901最高(P<0.01),BGC-823、MGC-803次之(两者间无显著性差异,P>0.05),HGC-27表达水平最低(P<0.01),其表达与细胞分化程度呈正相关趋势。结论PTEN基因启动子区异常甲基化可能导致该基因转录表达失活,使其蛋白表达减少甚至缺失,这可能是导致胃癌发生、发展的原因之一。     

Bacteria and cancer--antagonisms and benefits

There is considerable historical and recent evidence concerning the antagonisms between acute bacterial infections or their toxins and cancer and allied diseases. These data provide renewed incentives to undertake clinical programmes with mixed bacterial vaccines in many countries at the present time.     

Religiosity and physical and emotional functioning among African American and White colorectal and lung cancer patients

The literature suggests that religiosity helps cope with illness. The present study examined the role of religiosity in functioning among African Americans and Whites with a cancer diagnosis. Patients were recruited from an existing study and mailed a religiosity survey. Participants (N = 269; 36% African American, 56% women) completed the mail survey, and interview data from the larger cohort was utilized in the analysis. Multivariate analyses indicated that in the overall sample religious behaviors were marginally and positively associated with mental health and negatively with depressive symptoms. Among women, religious behaviors were positively associated with mental health and negatively with depressive symptoms. Religiosity was not a predictor of study outcomes for men. Among African Americans, religious behaviors were positively associated with mental health and vitality. Among Whites, religious behaviors were negatively associated with depressive symptoms. These findings suggest a mixed role of religious involvement in cancer outcomes. The current findings may have applied potential in the areas of emotional functioning and depression.     

VEGF及KDR在大肠腺瘤和腺癌中的表达及意义

目的：探讨VEGF和KDR在大肠腺瘤和大肠腺癌中的表达及临床病理特征的关系。方法：大肠腺瘤和大肠腺癌组织标本各100例,采用免疫组织化学染色法检测VEGF和KDR在标本中的表达情况。结果：VEGF和KDR在大肠腺癌组中的阳性表达明显高于大肠腺瘤组（P〈0.05）;在正常大肠黏膜均未见VEGF和KDR表达的阳性染色;VEGF阳性表达组中KDR的阳性表达率为70%,显著高于VEGF阴性表达组中KDR的阳性表达率16%,两组比较有统计学意义（P〈0.01）。结论：大肠腺癌组织中KDR的表达与肿瘤大小、转移情况、浸润深度密切相关;VEGF和KDR在大肠腺瘤中的表达与患者的年龄、性别及分型均无相关性,而与增生程度相关（P〈0.05）。在大肠腺癌患者中VEGF及KDR表达更高,二者具有协同效应。     

Renal irradiation and the pharmacology and toxicity of methotrexate and cisplatinum

We used a rat model to study the effects of renal irradiation on the pharmacology of methotrexate (MTX) and cisplatinum (cis-Pt). Unanesthetized rats were given bilateral kidney irradiation (20 Gy in 9 fractions). At 9 months after irradiation, 3% of the animals had died and survivors showed moderately impaired renal function. At 15 months, 30% of the animals had died and survivors showed severely impaired renal function. Some animals were given i.v. MTX 1 week to 15 months after irradiation. In irradiated rats, the area under the MTX plasma clearance curve equaled that of controls through 6 months, and was significantly above controls from 9 months on. Other animals were given i.p. cis-Pt 1 week to 9 months after irradiation. The acute toxicity of cis-Pt was the same in control and irradiated rats when cis-Pt was given immediately before or after irradiation. Beginning 3 months after irradiation there was a progressive increase in cis-Pt toxicity and a simultaneous decrease in urinary platinum excretion. Irradiated animals that survived cis-Pt treatment showed increased radiation nephritis; the greatest effect occurred when cis-Pt was given 3 months or more after irradiation. MTX and cis-Pt clearance decreased when renal dysfunction was first observed and changes in renal function preceded changes in drug clearance and toxicity.     

Fruit and vegetables and cancer risk

The possibility that fruit and vegetables may help to reduce the risk of cancer has been studied for over 30 years, but no protective effects have been firmly established. For cancers of the upper gastrointestinal tract, epidemiological studies have generally observed that people with a relatively high intake of fruit and vegetables have a moderately reduced risk, but these observations must be interpreted cautiously because of potential confounding by smoking and alcohol. For lung cancer, recent large prospective analyses with detailed adjustment for smoking have not shown a convincing association between fruit and vegetable intake and reduced risk. For other common cancers, including colorectal, breast and prostate cancer, epidemiological studies suggest little or no association between total fruit and vegetable consumption and risk. It is still possible that there are benefits to be identified: there could be benefits in populations with low average intakes of fruit and vegetables, such that those eating moderate amounts have a lower cancer risk than those eating very low amounts, and there could also be effects of particular nutrients in certain fruits and vegetables, as fruit and vegetables have very varied composition. Nutritional principles indicate that healthy diets should include at least moderate amounts of fruit and vegetables, but the available data suggest that general increases in fruit and vegetable intake would not have much effect on cancer rates, at least in well-nourished populations. Current advice in relation to diet and cancer should include the recommendation to consume adequate amounts of fruit and vegetables, but should put most emphasis on the well-established adverse effects of obesity and high alcohol intakes.     

New and emerging radiosensitizers and radioprotectors

The combination of chemotherapy and radiation has led to clinical breakthroughs in several disease sites, and current work continues to define optimum combinations of proven chemotherapy as well as more recently available, noncytotoxic agents. Administration of systemic therapies allows modulation of radiation response to improve tumor control (radiosensitization) or to prevent normal tissue toxicity (radioprotection). Substantial progress has been made in identifying the targets of standard chemotherapeutic radiation sensitizers and protectors as well as in the introduction of a new generation of molecularly targeted therapies in combination with radiation. We have reviewed the most recent, predominantly early phase clinical trials combining systemic agents with radiation. Although the proof of an improved schedule ultimately needs to come from well-run Phase III trials, the search among schedules could be shortened by the use of surrogate endpoints such as presence of active drug metabolites in the tumor. This has been accomplished only in a few cases and needs to become a more standard part of radiation sensitizer and protector trials.