p53和Bcl-2 mRNA表达在三七皂苷R1诱导HL-60细胞凋亡中的作用

目的：探讨三七皂苷R1诱导HL-60细胞凋亡的作用机制.方法：采用MTT比色法观察三七皂苷R1对人白血病细胞株HL-60细胞增殖的抑制作用.采用流式细胞术检测细胞凋亡改变,并以RT-PCR检测凋亡调节基因p53、Bcl-2的表达.结果：三七皂苷R1能明显抑制人白血病细胞株HL-60细胞的生长,且呈时间和浓度依赖性.三七皂苷R1作用后人白血病细胞株HL-60细胞呈现凋亡特征,流式细胞术显示凋亡细胞比例升高.RT-PCR检测可见p53 mRNA表达显著增加,而Bcl-2 mRNA表达减少.结论：三七皂苷R1能诱导人白血病细胞株HL-60细胞凋亡,其作用可能与凋亡调节基因p53的上调和Bcl-2的下调有关.     

三七皂苷R1通过线粒体相关通路促进白血病细胞株HL-60凋亡

目的:观察三七皂苷(notoginsenoside) R1对白血病细胞株HL-60凋亡的影响,探讨其可能的作用机制.方法:采用MTT法和流式细胞术(Annexin V-FITC双染法)分别检测三七皂苷R1(10、20、40及80 μmol/L)处理HL-60细胞12、24、36及48 h后HL-60细胞的凋亡情况,Western blotting检测HL-60细胞内Bcl-2、Bax及细胞色素C(cytochrome-C,Cyt C)蛋白的表达水平,JC-1染色法观察HL-60线粒体膜电位的变化.结果:MTT和流式细胞术检测显示三七皂苷R1浓度依赖性诱导HL-60细胞的凋亡,且细胞存活率随处理时间的增加而降低;与空白对照组相比,加入三七皂苷R1后细胞中Bcl-2蛋白表达显著减少[(0.45 ±0.03) vs (1.00 ±0.00),P＜0.05]、Bax蛋白表达显著增加[(1.72 ±0.08) vs (1.00±0.00),P＜0.05];Bcl-2/Bax比值减小[(0.21±0.01) vs (1.00±0.00),P＜0.05];线粒体膜电位降低[(0.56±0.09) vs (1.00±0.00),P＜0.05];胞质(cyto)中Cyt-C蛋白表达水平显著下降[(0.42±0.03) vs (1.00±0.00),P＜0.05].结论:三七皂苷R1可显著诱导HL-60细胞凋亡,其作用机制可能是通过线粒体通路促进细胞的凋亡;本实验可为三七皂苷R1用于临床治疗白血病提供实验依据.     

硫化砷对白血病细胞的生长抑制及作用机制

 目的 研究硫化砷（As4S4）通过体外培养对白血病细胞HL-60细胞的生长抑制作用及其分子机制。方法 以不同浓度（7.5 ~ 60 mmol／L）的As4S4作用于体外培养HL-60细胞12 ~ 48 h,四甲基偶氮唑蓝（MTT）法检测细胞生长抑制率,流式细胞仪观察细胞凋亡率,免疫组化法检测bcl-2、p53蛋白表达,应用RT-PCR法检测HL-60细胞中p53 mRNA表达。结果 不同浓度的As4S4作用12 ~ 48 h后,可显著抑制HL-60细胞的生长,呈时间浓度依赖性,并诱导细胞发生凋亡,凋亡率为30.18 % ~ 70.98 %,不同作用时间、不同浓度间凋亡率差异有统计学意义（P＜0.01）,RT-PCR结果显示As4S4作用24 h后,下调p53 mRNA的表达。免疫组化结果显示,bcl-2、p53蛋白表达逐渐降低,并呈浓度依赖性。结论 As4S4能够显著抑制HL-60细胞的生长。诱导其凋亡,并下调bcl-2、p53的表达,可能是其重要机制。     

环氧合酶-2抑制剂对白血病细胞HL-60的化疗增敏作用及机制

 目的　观察环氧合酶-2（COX-2）抑制剂塞来昔布对白血病细胞株HL-60的化疗增敏作用,并对其机制进行初步探讨。方法　MTT法评估塞来昔布、多柔比星及二者联合对HL-60细胞的生长抑制效应;流式细胞术（FCM）检测细胞的凋亡;反转录聚合酶链反应（RT-PCR）检测Survivin基因的表达;Western blotting检测Survivin蛋白的表达。结果　多柔比星联合塞来昔布5和10 μmol／L对HL-60细胞的半数抑制浓度（IC50）分别为0.25及0.16 μg／ml,明显低于多柔比星单用的IC50（0.48 μg／ml）;多柔比星0.10 μg／ml联合10 μmol／L塞来昔布下调Survivin基因mRNA及蛋白的表达;联合塞来昔布5和10 μmol／L的凋亡率[分别为（13.07±1.66）%及（22.36±1.84）%]较多柔比星0.10 μg／ml单用[（5.72±1.25）%]明显增加（P＜0.01）。结论　COX-2抑制剂塞来昔布对白血病细胞株HL-60具有明显的化疗增敏作用,其初步机制涉及下调Survivin的表达,增加细胞凋亡。     

急性髓系白血病细胞中 DICER1 基因的表达及其功能研究简

目的：检测急性髓系白血病细胞株HL-60、KG-1细胞中DICER1基因的表达水平,研究DICER1基因沉默对HL-60、KG-1细胞增殖、凋亡的影响,探寻DICER1在白血病发病机制中的作用。方法：应用Real-time PCR和Western blot检测DICER1在白血病细胞株HL-60、KG-1中mRNA和蛋白的相对表达水平。用Lipofectamine TM LTX 将DICER-shRNA载体转染HL-60、KG-1细胞,Real-time PCR和Western blot的方法从mRNA和蛋白水平检测DICER1的干扰效率。CCK-8法检测DICER1干扰后对白血病细胞增殖的影响,流式细胞仪检测DICER1干扰后白血病细胞凋亡率。结果：以正常HEK293细胞为对照,白血病细胞株HL-60、KG-1中DICER1 mRNA和蛋白的表达水平显著高于正常HEK293细胞（P＜0.05）。DICER1-shRNA转染HL-60、KG-1细胞5天后,DICER1 mRNA和蛋白表达水平显著下降,干扰效果显著（P＜0.05）;CCK-8实验结果表明：与对照组细胞相比,DICER1干扰后白血病细胞增殖力显著降低（P＜0.05）;流式细胞分析表明：与正常细胞和对照组细胞比较,DICER1干扰后白血病细胞凋亡显著增加（P＜0.01）。结论：DICER1在白血病细胞株HL-60、KG-1中高表达,具有促进白血病细胞增殖,抑制凋亡的作用。     

黄芩苷作用HL-60细胞前后c-myc基因表达的变化

 目的 研究中药黄芩苷（baicalin）对人髓系白血病细胞株HL-60细胞增生、凋亡的影响及探讨c-myc基因在其中的作用。方法 培养人髓系白血病细胞株HL-60细胞,应用MTT法绘制细胞生长曲线观察黄芩苷对HL-60细胞增生的影响;DNA凝胶电泳观察细胞凋亡;RT-PCR检测黄芩苷作用前后c-myc基因mRNA表达水平的变化;Western blot检测黄芩苷作用前后c-myc蛋白表达水平的变化。结果　细胞生长曲线结果示黄芩苷能明显抑制HL-60细胞增生,半数抑制浓度（IC50）约为20μmol／L,DNA 片段化的检出表明黄芩苷能有效诱导HL-60细胞凋亡;黄芩苷作用后HL-60细胞c-myc基因和蛋白的表达水平均下降,并且随作用时间延长,表达下降更明显。结论 黄芩苷能有效抑制HL-60细胞增生,诱导其凋亡,c-myc基因可能参与了黄芩苷抑制HL-60细胞增生和诱导凋亡的过程。     

蛋白酶体抑制剂联合亚砷酸对白血病细胞株NB4的凋亡诱导效应

目的 观察蛋白酶体抑制剂硼替佐米(BOR)联合急性早幼粒细胞白血病(APL)凋亡诱导剂亚砷酸(ATO)对NB4细胞株的作用.方法 BOR单独及联合ATO作用于NB4细胞,应用MTT法观察细胞的生长抑制效应;流式细胞术检测细胞周期变化及凋亡率;RT-PCR方法检测survivin mRNA的表达.结果 MTT法显示BOR对NB4细胞具有生长抑制作用,且能增强ATO对细胞的杀伤作用;流式细胞仪检测可见明显凋亡峰及G2/M期细胞周期阻滞;RT-PCR检测发现两药单独应用均能下调survivin mRNA的表达,联合作用时具相加效应.结论 ATO与BOR联合作用较单独作用有更强的细胞杀伤及诱导细胞凋亡活性,细胞周期G2/M期的阻滞及survivin mRNA表达的下降是蛋白酶体抑制剂及亚砷酸对白血病细胞株联合诱导凋亡的可能机制.     

Survivin参与胰腺癌PaTu8988细胞对吉西他滨的耐药

目的:探讨凋亡抑制蛋白survivin在胰腺癌细胞株PaTu8988中的表达,及其与吉西他滨(gemcitabine,GEM)耐药的关系。方法:MTT法检测GEM(0.01、0.1、1.0、2.5、5.0、10.0μg/ml)对PaTu8988细胞生长的抑制作用,流式细胞术检测GEM作用后PaTu8988细胞的凋亡率,RT-PCR检测survivin mRNA在PaTu8988细胞中的表达。结果:高质量浓度GEM(≥1.0μg/ml)可显著抑制PaTu8988细胞的增殖、促进PaTu8988细胞的凋亡;而低质量浓度GEM(0.01、0.1μg/ml)作用不明显。低质量浓度GEM时间依赖性地上调PaTu8988细胞中survivin mRNA的表达;而质量高浓度GEM作用PaTu8988细胞后,sur-vivin mRNA的表达48 h时逐渐下降,而后逐渐上升。结论:胰腺癌PaTu8988细胞中survivin mRNA高表达,可能是其对GEM产生耐药的原因之一。     

VES对Her-2、p53共表达乳腺癌细胞的抑制作用及机制

目的:研究VES对Her-2、p53共表达乳腺癌细胞株MDA-MB-453细胞的增殖、凋亡的影响、通过检测Her-2、p53探讨VES抑制乳腺癌细胞生长的机制。方法:应用MTT法检测VES对MDA-MB-453细胞增殖的影响;流式细胞仪检测细胞周期变化及细胞凋亡;RT-PCR和免疫细胞化学法分别检测Her-2基因mRNA和Her-2、p53蛋白表达水平。结果:VES能抑制乳腺癌MDA-MB-453细胞增殖,随VES剂量的增加,抑制作用增强。其中20μg/ml VES处理组在48h后受到明显抑制,抑制率达52.25%;经VES处理后细胞出现凋亡,5μg/ml处理48h后,凋亡率为39.52%;药物干预组使肿瘤细胞大量阻滞于G1期(P<0.01);RT-PCR和免疫细胞化学法结果表明,VES能抑制Her-2基因mRNA的转录水平,从而抑制其蛋白的表达,也能降低p53蛋白的表达。结论:VES可诱导Her-2、p53共表达乳腺癌MDA-MB-53细胞凋亡,抑制增殖。其机制可能是通过抑制Her-2基因mRNA及蛋白的表达和通过抑制突变型p53蛋白的表达使细胞停滞于G1有关。     

野生型p53基因对肝癌细胞多药耐药的逆转作用及其相关机制

背景与目的：细胞凋亡的发生机制在肿瘤多药耐药中起重要作用,野生型p53基因是细胞凋亡的激活剂,与肿瘤多药耐药密切相关。本研究旨在探讨野生型p53基因能否实现对肝癌细胞多药耐药的逆转以及逆转的相关机制。方法：构建野生型P53蛋白表达序列的真核表达载体pCR3．1-p53,用脂质体转染技术建立人肝癌细胞Bel-7402的p53转染细胞株,对转染细胞株进行MTT实验,观察p53基因对肿瘤细胞生长的抑制作用和对肝癌细胞对长春新碱（vincristine,VCR）药物敏感性的影响,姬姆萨染色法观察细胞形态,免疫组织化学SP法检测细胞P糖蛋白（P—glycoprotein,P—gp）的表达,逆转录PCR法检测细胞内mdr1、MRP、GSTπ、TopoⅡ mRNA的表达。结果：转染p53的Bel—p53细胞生长明显慢于未转染的Bel-7402细胞。转染野生型p53的Bel-p53细胞在VCR浓度为0．01μg／ml,0．1μg／ml,1．0μg／ml,10μg／ml,25μg／ml时,其药物敏感性增加;VCR作用最佳浓度为1．0μg／ml。形态学检查转染细胞,在VCR作用下细胞数明显减少,细胞散在不成片、细胞高度水肿、胞体不规则突起,可见核固缩、核裂解、核溶解。p53基因对Bel-7402细胞的mdr1／P—gP的表达有明显的抑制作用．对TopoⅡα基因的表达有上调作用,对GSTπ、MRP基因表达没有影响。结论：p53基因对肝癌细胞多药耐药有逆转作用．其逆转机制可能与降低mdr1／P—gp的表达、上调TopoⅡα的表达．从而增加细胞内VCR药物浓度和VCR药效有关。     

E-钙粘蛋白及PTEN基因编码蛋白与胃癌浸润转移

目的:观察抑癌基因PTEN蛋白和ECD在胃癌组织中的表达,探讨其与胃癌生物学行为及预后的关系。方法:以兔抗人PTEN多克隆抗体、鼠抗人ECD单克隆抗体,采用SABC免疫组化法,检测100例胃癌手术切除标本中拟测指标的表达。以χ2和Logrank检验对结果做统计学分析。结果:ECD、PTEN蛋白在非癌胃粘膜中均见表达;在胃癌组织中表达下调或缺失。ECD异常表达率为42.0%;弥漫型胃癌异常表达率(48.57%),明显高于肠型胃癌(26.67%),(P<0.05);ECD异常表达与浸润深度有关(P<0.05)。胃癌组织中PTEN蛋白缺失率为59%;弥漫型胃癌缺失率(65.71%)明显高于肠型胃癌(43.33%),(P<0.05);伴淋巴结转移的胃癌缺失率(64.47%)明显高于无淋巴结转移者(41.67%),(P<0.05);PTEN蛋白缺失的患者比阳性表达者预后差(P=0.0066)。65.85%PTEN阳性表达者同时伴ECD正常表达。结论:两种标志物与胃癌浸润转移有关,PTEN表达与胃癌患者预后密切相关。将两种指标联合检测,可作为正确判断胃癌患者预后,指导临床治疗的分子生物学指标。     

Cytologic classification of precancer and cancer of the endometrium and esophagus and of malignant lymphomas

The paper discusses cytological classifications of precancer and cancer of the endometrium, esophagus and malignant lymphomas presented by cytologists from five Soviet research institutes of oncology. The classifications were based on the data of 4400 cases in conformity with WHO histologic classifications.     

世界卫生组织骨质疏松症防治工作报告和防治建议

引 言 作为对第51号综合处理非传染性疾病预防与控制的世界卫生组织决议的反应,1998年7月WHO成立了致力于不断完善对骨质疏松预防和治疗策略的工作小组。小组成员来自世界各国致力于骨质疏松研究的知名专家。Harry K.Genant为本届主席。这一项世界范围内的骨质疏松教育计划旨在通过世界范围的研究,不断改善对骨质疏松的诊断水平和发展并完善对骨质疏松病人的合理治疗。其重点将以发展中国家为主。并为各国政府及其卫生部门和病人群体提供世界性有关骨质疏松症的总体的、完整的指导性资料。该项研究、教育计划的实施将由世界各国的骨质疏松症研究和治疗机构共同完成,并经权威学术机构、政府和非政府组织进行有针对性的回顾研究,最终由WHO审议通过。     

Schwannomas of Head and Neck and Review of Literature

Benign nerve cell tumours have been given various names like schwannoma, neurilemmoma, neurinoma, neurofibroma, spindle cell tumours etc. Extra cranial head and neck schwannomas usually present as solitary and well-demarcated lesions. The lesion can cause secondary symptoms, such as nasal obstruction, dysphasia, and hoarseness, depending upon the location of the lesion. Fine needle aspiration cytology, CT scans, and MRI may be of limited help in the diagnosis of schwannomas. The treatment is complete surgical excision of the benign tumour and postoperative histopathological examination establishes the final diagnosis.     

Quality of life and care in leukemia,myeloma and non-malignant disease. Opinions of patients and relatives,and effects of geography and time

In a questionnaire study 140 subjects answered 4200 questions in 1980 and 1986. They consisted of patients with myeloma, acute leukemia, lung carcinoma, and non-malignant disease and their relatives. In 22 additional cases the questionnaire was not answered. The results show that myeloma patients are less content with the general care than leukemia patients (P < 0.05). Similarly, relatives of deceased myeloma patients are less satisfied with the information given to them than relatives of deceased leukemia patients (P < 0.001). The information has improved with time, however, since the patients were more satisfied in 1986 than in 1980 (P < 0.001) and relatives of myeloma patients still alive were more satisfied than relatives of patients who had died earlier (P < 0.001).     

A comparative study of knowledge and awareness of colorectal and breast cancerA comparative study of knowledge and awareness of colorectal and breast cancer

Aims: To assess and compare knowledge and awareness of colorectal cancer and breast cancer in a sample of the general population. Methods: Eleven hundred visitors to six different outpatient clinics, in a University Hospital, were given a study-specific questionnaire, based on educational material from the British Association of Cancer United Patients (CancerBACUP). The questionnaire consisted of 12 statements on the incidence, presentation, detection, treatment and prognosis of colorectal and breast cancer. Results: One thousand and sixty-eight individuals returned the questionnaire. One thousand and four completed questionnaires were analysed. The mean age (SD) of respondents was 50.1 (17.2) years, and the male to female ratio was 2:3. Respondents had read more about breast than about colorectal cancer (60.3%vs 32.4%,P <0.0001, McNemar's test). The proportion of correct answers for each statement on breast cancer was higher than for answers to corresponding items on colorectal cancer. Mean overall scores (95% CI) for breast and colorectal cancer were 88.1 (86.9, 89.2) and 64.4 (62.5, 66.3) respectively, the mean difference (95% CI) being 23.7 (22.0, 25.5). Scores were higher for breast cancer irrespective of age or gender. Conclusion: There is a low level of understanding of colorectal cancer in the general population when compared to breast cancer. This highlights the importance of public education in this common cancer.     

Prospective study of fruit and vegetable consumption and incidence of colon and rectal cancers

BACKGROUND: Frequent consumption of fruit and vegetables has been associated with a reduced risk of colorectal cancer in many observational studies. METHODS: We prospectively investigated the association between fruit and vegetable consumption and the incidence of colon and rectal cancers in two large cohorts: the Nurses' Health Study (88 764 women) and the Health Professionals' Follow-up Study (47 325 men). Diet was assessed and cumulatively updated in 1980, 1984, 1986, and 1990 among women and in 1986 and 1990 among men. The incidence of cancer of the colon and rectum was ascertained up to June or January of 1996, respectively. Relative risk (RR) estimates were calculated with the use of pooled logistic regression models accounting for various potential confounders. All statistical tests were two-sided. RESULTS: With a follow-up including 1 743 645 person-years and 937 cases of colon cancer, we found little association of colon cancer incidence with fruit and vegetable consumption. For women and men combined, a difference in fruit and vegetable consumption of one additional serving per day was associated with a covariate-adjusted RR of 1.02 (95% confidence interval [CI] = 0.98-1.05). A difference in vegetable consumption of one additional serving per day was associated with an RR of 1.03 (95% CI = 0.97-1.09). Similar results were obtained for women and men considered separately. A difference in fruit consumption of one additional serving per day was associated with a covariate-adjusted RR for colon cancer of 0.96 (95% CI = 0.89-1.03) among women and 1. 08 (95% CI = 1.00-1.16) among men. For rectal cancer (total, 244 cases), a difference in fruit and vegetable consumption of one additional serving per day was associated with an RR of 1.02 (95% CI = 0.95-1.09) in men and women combined. None of these associations was modified by vitamin supplement use or smoking habits. CONCLUSIONS: Although fruits and vegetables may confer protection against some chronic diseases, their frequent consumption does not appear to confer protection from colon or rectal cancer.