P53对涎腺腺样囊性癌细胞端粒酶活性的抑制作用

目的为了探讨P53基因对腺样囊性癌细胞端粒酶活性的抑制作用及机制。方法构建携带人野生型P53基因的腺病毒表达载体，以脂质体法瞬时转染腺样囊性癌SACC-83细胞，RT-PCR检测转染细胞P53基因mRNA的表达，TRAP-PCR-ELISA法检测转染细胞端粒酶活性的改变。并将P53基因与含有hTERT启动子核心调控区的荧光素酶报告基因pGL2—630共转染SACC-83细胞，测定转染细胞荧光素酶报告基因活性。结果1．瞬时转染含人野生型P53基因的重组腺病毒表达载体p△E1-P53于腺样囊性癌SACC-83细胞后，其P53基因mRNA的表达明显增强；2．基因转染后，SACC-83细胞内源性端粒酶活性显著降低。3．P53基因与含有hTERT启动子核心调控区的荧光素酶报告基因pGL2-630共转染SACC-83细胞后，其荧光素酶活性显著下降。结论外源性表达P53基因可以降低腺样囊性癌细胞SACC-83细胞端粒酶活性，并可能通过抑制端粒酶hTERT基因启动子的转录活性实现。     

RNA干扰端粒酶活性对HeLa细胞生物学行为的影响

目的 观察RNA干扰(RNAi)体外培养的HeLa细胞端粒酶催化亚单位(hTERT)对HeLa细胞生物学行为的影响,进一步探讨端粒酶活性与肿瘤细胞恶性生物学行为的相关性.方法 体外转录法设计合成4条针对hTERT基因的shRNA,脂质体转染HeLa细胞后经免疫荧光染色和端粒重复序列扩增-酶联免疫法(TRAP-ELISA)测定端粒酶活性,筛选出端粒酶沉默效果最佳片段即B链shRNA.以B链shRNA转染HeLa细胞为实验组,转染无关siRNA的HeLa细胞为对照组,显微镜下观察细胞在纤维黏连蛋白(FN)上的铺展;CCK-8细胞计数试剂盒检测细胞在FN上黏附;划痕实验评价细胞迁移;Boyden小室侵袭实验检测细胞侵袭能力.结果 铺展实验显示细胞接种到FN上30 min时,对照组铺展细胞的比率为(31.3±7.9)%,而实验组铺展细胞的比率仅为(5.6±2.3)%,两组差异有统计学意义(P<0.01);2 h后对照组和实验组铺展细胞的比率分别为(79.4±4.8)%和(26.3±6.1)%,两组差异仍有统计学意义(P<0.01);24 h后两组所有细胞几乎均呈铺展状态.细胞黏附实验显示细胞在FN上黏附30 min时对照组细胞黏附率为(83.7±5.4)%,而实验组的细胞黏附率为(67.2±2.8)%,明显低于对照组(P<0.05).划痕实验检测细胞的迁移能力显示实验组细胞24 h迁移率为(27.1±6.2)%,明显低于对照组(58.7±15.0)%.Boyden小室侵袭实验显示在Matrigel胶上培养4 h后,实验组和对照组侵袭的细胞数分别为75.7±14.5和165.1±11.0,差异有统计学意义(P<0.05).结论 降低体外培养HeLa细胞的端粒酶活性使细胞的生物学特性发生改变,表现为减低了HeLa细胞的恶性生物学行为.     

端粒酶反义腺病毒载体对乳腺癌细胞MCF-7端粒酶的抑制作用

端粒酶ＲＮＡ的反义地人乳腺癌细胞系ＭＣＦ－７细胞端粒酶活性的影响。方法用重组腺病毒转移并表达端粒酶ＲＮＡ的反义ｃＤＮＡ,采用基因重组腺脂质体共转当闰酶反义重组病毒,用Ｓｏｕｔｈｅｒｎ杂交鉴定病毒的整合功能,用ＴＲＡＰ－ 染法检测端粒酶活性。结果ＭＣＦ－７细胞是恶性乳腺癌的典型细胞系。对对照组ＭＣＦ－７、ＭＣＦ－７、ｖＡｄ－ＡＡＶ细胞相比,反义病毒感染后的细胞是恶性乳腺癌的典型细胞系。与对照组ＭＣＦ     

肺癌患者外周血单核细胞端粒酶活性表达与分析

目的通过测定肺癌患者、良性肺病患者和健康人外周血端粒酶活性(TA),探讨其对肺癌的诊断价值。方法采用PCR-TRAP-ELISA法检测不同病理类型、不同临床分期的肺癌患者42例以及良性肺病患者20例和正常人15例外周血单个核细胞(PBMNC)端粒酶活性,并测定肺癌患者等的血CEA水平,进行相关分析。结果42例肺癌患者TA升高的阳性率达69.05%(29/42),OD值为0.45±0.37;20例良性肺病患者只有2例TA升高呈阳性,OD值为0.11±0.06,而15例正常人全部呈阴性,OD值为0.08±0.03。肺癌组血TA升高的阳性率及OD值均高于良性肺病组和正常对照组,差异有显著性(P<0.005)。PCR-TRAP-ELISA法检测肺癌组TA特异度为90%,灵敏度为69.05%,优于CEA检测(P<0.01)。肺癌I期TA阳性率为25%(1/4),而IV期阳性率为100%(8/8),TA高低与临床分期呈明显正相关(r=0.585,P=0.001)。结论1.PCR-TRAP-ELISA法检测外周血单个核细胞TA升高的阳性率明显高于CEA检测,可联合或替代CEA应用于肺癌的诊断及鉴别诊断;2.外周血TA可作为分子指标,辅助TNM分期,用于指导肺癌的治疗及预后判断等。     

Inhibition of Lonp1 induces mitochondrial remodeling and autophagy suppression in cervical cancer cells

Lon protease 1(Lonp1) is an ATP-dependent protease located in the mitochondrial matrix and plays a crucial role in preserving normal mitochondrial function. Lonp1 overexpression is associated with tumorigenesis in various cancer types, including cervical cancer. In the present study, we show that the Lonp1 content is elevated in cervical cancer tissues compared to cervical paracancerous tissues. Conversely, Lonp1 knockdown suppresses cervical cancer cell proliferation, migration and invasion but promotes apoptosis. Mechanistically, Lonp1 knockdown decreases area of mitochondrial networks and induces mitochondrial depolarization. Furthermore, Lonp1 inhibition reduces the level of LC3-II/I, PINK1 and Parkin, but promotes the level of p62. Collectively, our study suggests that the anti-cancer effect caused by Lonp1 downregulation likely contributes to mitochondrial remodeling and suppression of autophagy and mitophagy.     

胃癌单抗与柔红霉素和氨甲喋呤交联物的制备及其细胞毒作用

采用葡聚糖氧化将胃癌单抗(McAb)与抗癌药物柔红霉素(DNR)和氨甲喋呤(MTX)同时交联(McAb-PAD<分别采用噻唑蓝活细胞染色法(MTT 法)及~3H-TR 掺入法检测交联物的细胞毒作用,结果表明两种检测方法敏感性无明显差异,并且证实文联物对肿瘤靶细胞具有较强的选择性杀伤效应。     

Inhibition of Neisseria gonorrhoeae by sodium polyanetholesulfonate.

Sodium polyanetholesulfonate (SPS), in concentrations commonly used in blood culture media, inhibited the growth of a significant number of isolates of Neisseria gonorrhoeae in an agar dilution system. This SPS toxicity, shown to be bactericidal when examined in broth culture, could be reversed by hemoglobin and gelatin. Gelatin in 1% concentration allowed optimal growth of SPS-sensitive isolates in the presence of 0.025% SPS. Of 50 clinical isolates of N. gonorrheae tested under simulated blood cultures conditions with SPS, 16 isolates failed to grow on subculture at days 1, 3, and 10 after inoculation. Recovery was delayed with eight isolates as compared to controls. Early subcultures at 4, 8, and 12 h failed to recover SPS-sensitive isolates, whereas 1% gelatin, added even as late as 8 h after inoculation, reversed the SPS toxicity. The data reported suggest that SPS at concentrations routinely used in blood cultures can delay or prevent isolation of N. gonorrhoeae, but 1% gelatin can eliminate this adverse effect.     

Inhibition on LS-174T cell growth and activity of telomerase in vitro and in vivo by arsenic trioxide.

Arsenic trioxide (As(2)O(3)) shows a significant therapeutic effect upon acute promyelocytic leukemia (APL) and can induce the apoptosis of NB(4) cells, which attracts scholars' great attention. Especially, the therapeutic effect on solid carcinoma has been paid more close attention to. The present study is to evaluate the effect of As(2)O(3) on human colorectal carcinoma cells (LS-174T cell) and the activity of telomerase in vitro and in vivo. This research made use of the electron microscope, polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA), fluorescence-activated cell sorter (FACS), MTT in vitro and in vivo (LS-174T xenograft model of nude mice). With the increasing concentration of As(2)O(3), the ratio of living cells to dead cells decreased significantly, and the IC(50) value was 5.23mumol/L; cells of the experimental groups endured a series of morphological changes similar to the features of apoptosis. Apoptosis curve of FACS pictures appeared after 24h, and the cells showed apoptosis in a time-dependent manner; As(2)O(3) can inhibit the activity of telomerase of the cell extraction, obviously, in a concentration-dependent and time-dependent manner after 24h. As to the inhibition impact of As(2)O(3) on the xenograft model of nude mice in the two indexes, tumor volume and weight, there was a significant difference between As(2)O(3) and the control group; there was no difference between As(2)O(3) and the fluorouracil (5-FU) group; in the group of peritoneal injections of As(2)O(3), the cancer cells connected loosely with each other, nucleus changed markedly, and heterochromatin concentrated under the nucleus membrane. From the in vitro and in vivo experiment, we can see that As(2)O(3) inhibited LS-174T cell growth mainly by inducing cell apoptosis, partly by the inhibition of telomerase activity.     

丙型肝炎病毒核心蛋白在HepG2细胞中的表达及其对端粒酶活性的影响

目的 建立HCV核心蛋白细胞表达模型，并探讨其对细胞端粒酶活性的影响。方法 用PCR法扩增出HCV核心基因cDNA，将其插入真核表达载体pBK-CMV的HindⅢ和BamHⅠ位点间，构建重组质粒pBK-HCVc。再将重组质粒pBK-HCVc和空载体分别导入肝癌细胞株HepG2中，G418筛选，RT－PCR、免疫组化和蛋白印迹鉴定HCV核心蛋白表达。PCR－ELISA法检测端粒酶活性。结果 构建的pBK-HCVc质粒在HepG2细胞中有稳定表达。表达HCV核心蛋白的细胞HepG2-C的端粒酶活性较转染空载体的细胞HepG2-CMV明显升高。结论 HCV核心蛋白上调了端粒酶活性，可能是HCV诱发肝细胞癌的一种途径。     

DPC4基因转染对结肠癌细胞生长的抑制作用及其作用机制

目的 研究DPCA基因转染对结肠癌细胞生长及p21^WAFI mRNA表达的影响。方法 构建pcDNA3．1-DPCA真核表达质粒．利用脂质体转染技术将pcDNA3．1质粒和pcDNA3．1-DPCA质粒分别导入结肠癌细胞系SW620;采用免疫细胞化学和Western蛋白印迹检测细胞中DPCA基因的表达;通过检测细胞生长曲线、克隆形成实验研究DPCA基因转染对SW620细胞生长的抑制作用。通过逆转录．聚合酶链反应(RT-PCR)检测各组细胞内p21^WAFI mRNA的表达。结果 转染DPC4基因后,在SW620细胞中可检测到高表达的DPCA蛋白;细胞生长倍增时间(74h)明显延长;细胞克隆形成率(21％)明显降低。DPCA基因转染后SW620细胞p21^WAFI mRNA含量增加。结论 DPC4基因的高表达能够抑制结肠癌细胞的生长,DPCA基因可能通过诱导p21^WAFI基因的表达而抑制结肠癌细胞的生长。     

乳腺癌细针穿刺标本中端粒酶检测的诊断意义

目的 检测乳腺癌细针穿刺细胞标本中的端粒酶,探讨其在乳腺癌辅助诊断中的临床意义。方法 采用聚合酶链反应－端粒末端重复序列技术检测９９例乳腺细针穿刺标本（８３例乳腺癌、１２例乳腺良性病变和４例乳腺炎）中的端粒酶。     

硫代修饰型反义寡核苷酸抑制肺癌细胞系端粒酶活性及增殖的研究

了解人肺癌细胞系的端粒酶活性情况。探讨硫代修饰型端粒酶ＲＮＡ反义寡核苷酸封阻端粒酶ＲＮＡ,对癌细胞代谢,生长的抑制作用。方法采用端粒酶ＰＣＲ ＥＬＩＳＡ方法检测８种体外培养从肺癌细胞系端粒酶活性。合成端粒酶ＲＮＡ的反义硫代寡核苷酸（６聚体、９聚体、１２聚体）和随机序列寡核苷酸,分别导入ＬＴＥＰ－ａ－２细胞系,作用７２ｈ。采用端粒酶ＰＣＲ ＥＬＩＳＡ方法检测端粒酶活性,四甲基偶氮唑盐（ＭＴＴ）光吸收     

顺铂对葡萄膜黑色素瘤细胞端粒酶活性的抑制

目的 研究顺铂对人葡萄膜黑色素瘤细胞端粒酶活性的抑制作用,为临床治疗人葡萄膜黑色素瘤提供理论依据.方法 采用特定时间下不同浓度以及特定浓度下不同作用时间的端粒酶抑制剂顺铂作用于体外培养的人黑色素瘤细胞.采用多聚酶链反应--酶联免疫吸附测定(PCR-ELISA)及聚丙烯酰胺凝胶电泳法(PCR-PAGE)测定细胞中端粒酶活性的变化.结果 作用72 h,端粒酶活性在顺铂浓度达到0.10mg/L后开始下降,当浓度达到1.00mg/L后其活性下降至(0.173±0.007).当顺铂浓度固定10.00 mg/L,顺铂作用时间达到24 h后开始出现抑制作用,48 h时达到抑制高峰,端粒酶活性下降至(0.276±0.024).随着顺铂浓度的增加及作用时间的延长,端粒酶活性逐渐下降(P＜0.05).PCR-PAGE显示顺铂浓度增加及作用时间延长,端粒酶活性的显色条带越来越少.结论 顺铂可有效降低体外培养的人眼葡萄膜黑色素瘤细胞端粒酶活性,并呈浓度和时间依赖性.     

双歧杆菌脂磷壁酸对HL-60细胞端粒酶活性的影响

目的 探讨双歧杆菌表面分子脂磷壁酸（ＬＴＡ）对体外培养的ＨＬ－６０白血病细胞端粒酶活性的影响。方法 采用ＰＣＲ－ＥＬＩＤＡ法检测经ＬＴＡ处理前后的ＨＬ－６０白血病细胞株端粒酶活性的改变。结果 经ＬＴＡ处理后,ＨＬ－６０白血病细胞的生长受到抑制,端粒酶活性明显降低。结论 双歧杆菌ＬＴＡ对ＨＬ－６０白血病细胞具有生长抑制作用,其抗肿瘤作用的机理可能与抑制肿瘤细胞的端粒酶活性有关。     

Change of telomerase activity in rectal cancer with chemoradiation therapy

Telomerase, an enzyme associated with cellular immortality, is expressed by most malignant cells and is inactive in most normal somatic cells, with the exception of proliferative stem cells, germ cells and activated lymphocytes. Measuring telomerase activity clinically may provide useful diagnostic and prognostic information of cancer. The purpose of this study was to investigate the change in telomerase activity following chemoradiation in rectal cancer, which almost always produces positive enzymatic activity. A total of 24 tumor tissue samples were used in this study, consisting of 12 paired specimens before and 4 weeks after chemoradiation. Telomerase activity was determined by PCR-based telomeric repeat amplification protocol (TRAP) assay. The telomerase activity was positive in 10 out of 12 patients (83%) in pre-irradiated and post-irradiated states. The levels of telomerase activity was decreased in 8 out of 10 patients after chemoradiation (80%) and two cases showed no change in enzymatic activity. One case showed no activity in either sample. The other case showed no enzymatic activity in the pre-irradiated sample, but showed weak activity in the post-irradiated sample. These data indicate that telomerase activity in rectal cancer is reduced after neoadjuvant chemoradiation therapy, possibly suggesting a mechanism of downstaging following chemoradiation therapy in cancer.     

Inhibition of mycoplasma-induced lymphocyte activation by sodium aurothiomalate.

Sodium aurothiomalate, at concentrations of 10 to 150 microgram/ml of culture, inhibited rat lymphocyte stimulation by Mycoplasma pulmonis mitogen in a dose-dependent manner.