莱菔硫烷对人膀胱癌细胞周期的影响及机制研究

背景与目的:探讨莱菔硫烷对人膀胱癌细胞(T24)细胞周期的影响及作用机制。材料与方法:采用噻唑蓝(MTT)法研究不同浓度的莱菔硫烷对T24细胞生长的抑制作用并测定其半数抑制浓度(IC50);采用流式细胞仪检测莱菔硫烷对T24细胞周期的影响;采用westernblot研究莱菔硫烷对T24细胞中细胞周期蛋白依赖激酶抑制剂P16和P27的表达情况。结果:在较低剂量范围内(≤40μmol/L),随着作用剂量的增加,莱菔硫烷对T24细胞的生长的抑制作用也明显增强。10、20、40μmol/L莱菔硫烷的抑制率分别为(12.5±3.95)%,(25.0±2.50)%、(50.0±5.33)%;在较高剂量(60μmol/L~160μmol/L)时,这种抑制作用不再呈剂量依赖性;莱菔硫烷作用72h后的IC50值为(51.12±7.10)μmol/L;莱菔硫烷能使T24细胞周期阻滞于G0/G1期,20μmol/L莱菔硫烷作用48h后,在G0/G1峰之前出现凋亡峰;20μmol/L莱菔硫烷作用于T24细胞8、12、24h后能明显诱导P27蛋白的表达,作用早期(8h)时能诱导P16蛋白的表达。结论:莱菔硫烷能抑制T24细胞生长并使该细胞周期阻断在G0/G1期,其作用机制主要是通过诱导P27蛋白及早期诱导P16蛋白来实现的。     

聚合酶链反应单链构象多态性检测乳腺癌中P53基因突变

应用聚合酶链反应单链构象多态性方法，对２４例原发性乳腺癌肿瘤组织基因组ＤＮＡ进行了分析，结果表明：其中７例存在Ｐ５３基因的突变，突变频率约为３０％。同时对其中１０例进行Ｓｏｕｔｅｒｎｂｌｏｔ分析，有２例在ｃｈｒ１７Ｐ上存在等位基因的缺失，而其另一等位基因上均存在基因突变。     

Identification of genes associated with ovarian cancer metastasis using microarray expression analysis

Although the transition from early- to advanced-stage ovarian cancer is a critical determinant of survival, little is known about the molecular underpinnings of ovarian metastasis. We hypothesize that microarray analysis of global gene expression patterns in primary ovarian cancer and metastatic omental implants can identify genes that underlie the metastatic process in epithelial ovarian cancer. We utilized Affymetrix U95Av2 microarrays to characterize the molecular alterations that underlie omental metastasis from 47 epithelial ovarian cancer samples collected from multiple sites in 20 patients undergoing primary surgical cytoreduction for advanced-stage (IIIC/IV) serous ovarian cancer. Fifty-six genes demonstrated differential expression between ovarian and omental samples (P < 0.01), and twenty of these 56 differentially expressed genes have previously been implicated in metastasis, cell motility, or cytoskeletal function. Ten of the 56 genes are involved in p53 gene pathways. A Bayesian statistical tree analysis was used to identify a 27-gene expression pattern that could accurately predict the site of tumor (ovary versus omentum). This predictive model was evaluated using an external data set. Nine of the 27 predictive genes have previously been shown to be involved in oncogenesis and/or metastasis, and 10/27 genes have been implicated in p53 pathways. Microarray findings were validated by real-time quantitative PCR. We conclude that gene expression patterns that distinguish omental metastasis from primary epithelial ovarian cancer can be identified and that many of the genes have functions that are biologically consistent with a role in oncogenesis, metastasis, and p53 gene networks.     

食管癌3p24等位基因LOH及其扩增产物克隆的研究

目的；研究3p24EAβMD位点与食管癌的关系。为寻找该位点附近可能存在的抑癌基因奠定基础。方法：采用PCR—RFLP法检测45例食管癌患者3p24位点杂合缺失情况。并对该片段进行克隆。结果：在22例食管癌信息个体中共检出9例杂合缺失。并通过序列分析可知变化为点突变。结论：3p24EAβMD较高的杂合缺失率显示该位点附近可能存在潜在的抑癌基因。     

腺病毒介导的P16／CDKN2基因对TJ899细胞系活性的影响

（1）目的 研究5型腺病毒载体（Ad5)携带P16基因对恶性脑胶质瘤细胞系TJ899生长状态的影响。（2）方法 免疫组化（SP法）测定P16蛋白表达，MTT（methly thiazolyl tetrazolium,MTT)法测定恶性脑胶质瘤细胞系生长状态，克隆形成实验。（3）结果 重组体腺病毒能介导P16外源基因在恶性脑胶质瘤细胞系TJ899细胞中阳性表达，6d时肿瘤细胞生长抑制率为93%，并且能显地抑制肿瘤细胞的克隆形成能力。（4）结论 腺病毒介导P16基因能在肿瘤细胞中表达。并能明显抑制肿瘤细胞生长的状态。     

外阴尖锐湿疣人乳头瘤病毒感染的检测与分型

目的 了解患外阴尖锐湿疣人乳头瘤病毒(HPV)6型和11型的感染情况及PCR方法对尖锐湿疣诊断与分型的临床意义。方法 采用PCR方法测定160例尖锐湿疣患病题组织或分泌物中HPV6／11型及HPVl6／18型的感染率。结果 HPV6／11型感染率为95％(152／160)，HPVl6／18型感染率为5％(8／160)，HPV6／11型 HPVl6／18型混合感染率为1．3％(2／160)。结论 外阴尖锐湿疣患以HPV6型和11型感染为主。PCR方法是一种比较适合临床HPV检测与分型的极为敏感和特异的诊断方法。     

The activity of letrozole in patients with advanced or recurrent endometrial cancer and correlation with biological markers – a study of the National Cancer Institute of Canada Clinical Trials Group

A multicenter phase II trial was conducted to define the activity of letrozole in postmenopausal women with recurrent or advanced endometrial carcinoma, who had no more than one prior line of progestins and never had chemotherapy (except adjuvant). Archival paraffin-embedded tumor samples were retrieved to determine the expression level of estrogen (ER) and progesterone receptor (PgR), p53, HER-2, bcl-2 and PTEN protein, and phosphorylation status of protein kinase B (PKB/Akt). Thirty-two eligible patients were treated with letrozole at 2.5 mg daily continuously, of whom 10 (31%) had prior progestins. Of the 28 patients evaluated for response, one complete and two partial responses were noted; overall response was 9.4% (95% confidence interval 2-25%). Eleven patients had stable disease for a median duration of 6.7 months (range 3.7-19.3 months). Amongst 22 patients who had tumor blocks available, the proportion showing positive expression of the following markers includes: PgR (86%), ER (86%), PTEN (82%), phosphorylated PKB/Akt (59%), bcl-2 (45%), p53 (32%), and HER-2 (0%). None of these markers correlated with response to letrozole or disease progression. In conclusion, letrozole is well tolerated but has little overall activity in this cohort of women with endometrial cancer.     

Infection dynamics and virus-induced apoptosis in cell culture-based influenza vaccine production—Flow cytometry and mathematical modeling

Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population.     

微血管密度和p16基因表达对判定肾癌生物学行为的意义

目的 :探讨肿瘤内的微血管密度 (IMD)和 p1 6基因表达与肾细胞癌 (RCC)生物学行为的关系。 方法 :采用免疫组织化学方法 ,对 76例RCC患者的根治性肾切除标本 ,检测第Ⅷ因子相关抗原和 p1 6基因表达 ,分析IMD、p1 6基因表达与RCC分期、分级及预后的相关性。 结果 :IMD随临床分期升高而增加 (P <0 .0 5 ) ,而与分级无明显相关性 (P >0 .0 5 ) ,随访 5年内死亡者IMD明显升高 (P <0 .0 1 ) ;癌旁组织中 p1 6阳性率 (75 .0 % )显著高于RCC组织 (4 8.7% ) ,p1 6阳性表达随临床分期、病理分级升高而降低 (P <0 .0 5 ) ,而与IMD呈负相关性。结论 :IMD是预测RCC恶性行为的一个有用指标 ,IMD和p1 6基因表达可为RCC的疗效和预后判定提供重要的资料。