维生素E琥珀酸酯诱导耐药白血病K562／ADM细胞凋亡的研究

目的：研究维生素E琥珀酸酯(vitamin E succinate，VES)对多药耐药白血病K562／ADM细胞的诱导凋亡作用及分子机制。方法：以体外培养的K562／ADM细胞为研究对象，采用噻唑蓝(methyl thiazolyl tetrazolium，MTT)比色法检测细胞增殖活性，Wright-Giemsa染色、DNA凝胶电泳和流式细胞术(flow cytometry，FCM)检测细胞凋亡；FCM测定细胞Fas、Bcl-2和p53蛋白表达水平。结果：VES可显著抑制K562／ADM细胞的生长及增殖，P=0．004。光镜下可见K562/ADM细胞呈典型凋亡的形态学改变。DNA凝胶电泳显示典型的凋亡DNA梯形条带。FCM细胞周期分析显示，G1期阻滞，亚G1期细胞比例增高，P=0．005；Fas蛋白表达明显上调，P=0．002；Bcl-2蛋白表达下调，P=0．00～0；p53蛋白表达无明显变化。结论：VES可诱导K562/ADM细胞凋亡，作用机制可能与其上调Fas表达和下调Bcl-2表达有关。     

褪黑素介导小鼠肝H22肿瘤细胞自噬作用的研究

目的:探讨褪黑素（melatonin,MLT）对小鼠肿瘤细胞自噬信号通路的影响,从而阐述褪黑素发挥抗肿瘤效果的机制。方法:构建H22肝癌模型小鼠30只,每组10只,分别为生理盐水组、10 mg/kg褪黑素组、20 mg/kg褪黑素组。将小鼠肿瘤组织制备成切片后于光学显微镜和电镜下观察切片。利用荧光免疫组化法检测每个视野中的阳性细胞数平均百分比,以该切片阳性细胞百分比为基础进行计分。通过蛋白印迹试验对蛋白进行定性及定量测定,最后利用荧光显微镜下观察细胞内的绿色荧光,记录图像,分析计数LC3阳性细胞与总细胞数的比例,反映细胞发生自噬的程度。结果:MLT处理的动物其自噬形态较生理盐水组明显增多。随机成像后MLT处理组自噬液泡总数明显高于生理盐水组（P<0.05）。经MLT处理的H22荷瘤小鼠的肿瘤组织中Beclin-1、LC3-Ⅱ表达水平明显高于生理盐水组（P<0.05）。MLT处理的H22荷瘤小鼠肿瘤组织中,LC3亮点有所增强。MLT处理的H22荷瘤小鼠肿瘤组织中Akt和mTOR磷酸化水平较生理盐水组明显降低（P<0.05）。结论:褪黑素在H22荷瘤小鼠中诱导自噬,褪黑素能够诱导自噬过程标志蛋白Beclin-1和LC3的表达,并且能够抑制H22荷瘤小鼠中的Akt/mTOR信号通路。     

褪黑素对小鼠肝癌细胞增殖及p27Kip1、cyclin D1基因表达的影响

目的探讨褪黑素(melatonin MT)抑制H22小鼠肝癌细胞增殖的可能机制.方法通过体外细胞培养,分别采用不同剂量MT作用不同的时间,MTT显色技术检测细胞的增殖;RT-PCR检测MT作用4 d后,H22细胞中p27Kip1、cyclin D1mRNA的表达;免疫组化检测H22细胞中p27Kip1、cyclin D1蛋白的表达.结果MT具有抑制肝癌细胞的生长和增殖的作用,且具有时间依赖关系.MT诱导细胞凋亡的过程中,与对照组相比,MT药理剂量组H22细胞中的p27Kip1 mRNA及蛋白表达升高(P＜0.01);cyclin D1 mRNA及蛋白表达下降(P＜0.01).MT生理剂量组p27Kip1mRNA表达升高(P＜0.01),而p27Kip1蛋白表达水平与对照组相比差异无显著性(P＞0.05),cyclinD1 mRNA及蛋白表达均下降,差异元显著性(P＞0.05).结论MT抑制肝癌细胞的增殖可能与上调细胞周期抑制因子p27Kip1的表达,降低周期蛋白cyclin D1表达,进而延迟细胞周期的进程有关.     

苦参碱对小鼠H22肝癌细胞凋亡作用的实验研究

目的：研究中药苦参碱在体内外对小鼠H22肝癌细胞的诱导凋亡作用，探讨其可能的抗肿瘤作用机制。方法：Annexin V-FITC／PI双标记法检测苦参碱对H22细胞的早期促凋亡作用；免疫组织化学法检测苦参碱作用后H22细胞内Bcl-2、Bax两种凋亡相关蛋白的表达。建立H22肝癌移植瘤小鼠模型，观察苦参碱对荷瘤小鼠肿瘤生长情况的影响及肿瘤抑制率；电镜观察荷瘤小鼠肿瘤组织的超微结构改变；免疫组化方法检测小鼠肿瘤组织内Bcl-2、Bax的表达情况。结果：AnnexinV法检测到1．0mg／mL和1．5mg／mL苦参碱作用48h后H22细胞有早期凋亡改变，凋亡细胞百分率分别为11．71％和17．86％，与对照组相比差异有统计学意义（P〈0．05）。苦参碱对荷瘤小鼠肿瘤的抑制率达60％以上；免疫组化显示，苦参碱作用后H22细胞内及小鼠肿瘤组织内Bcl-2蛋白的表达水平下降，Bax蛋白表达增强。电镜证实苦参碱治疗后荷瘤小鼠肿瘤组织内有凋亡细胞和凋亡小体的存在。结论：苦参碱在体内体外都对小鼠H22肝癌细胞表现出较强的抗肿瘤作用和诱导凋亡作用。促凋亡作用与其上调细胞内Bax表达，抑制Bcl-2表达有关。     

维生素E琥珀酸酯诱导耐药白血病K562/ADM细胞凋亡的研究

目的:研究维生素E 琥珀酸酯(vitamin E succinate , VES)对多药耐药白血病K562/ADM细胞的诱导凋亡作用及分子机制。方法: 以体外培养的K562/ADM细胞为研究对象,采用噻唑蓝(methyl thiazolyl tetrazolium, MTT) 比色法检测细胞增殖活性, Wright Giemsa染色、DNA凝胶电泳和流式细胞术(flowcytometry, FCM)检测细胞凋亡;FCM测定细胞Fas、Bcl-2 和p53 蛋白表达水平。结果:VES可显著抑制K562/ADM细胞的生长及增殖,P= 0 .004。光镜下可见K562/ADM细胞呈典型凋亡的形态学改变。DNA凝胶电泳显示典型的凋亡DNA梯形条带。FCM细胞周期分析显示,G1 期阻滞,亚G1 期细胞比例增高,P=0 .005;Fas蛋白表达明显上调,P=0. 002;Bcl -2蛋白表达下调,P=0. 000;p53蛋白表达无明显变化。结论:VES可诱导K562/ADM细胞凋亡,作用机制可能与其上调Fas表达和下调Bcl 2表达有关。     

体外Fas介导肿瘤细胞凋亡过程中cyclins/CDKs的变化规律及调节机制

目的:探讨Fas介导的细胞周期特异性细胞凋亡发生过程中,细胞周期蛋白(cyclins)和细胞周期依赖性蛋白激酶(cyclin-dependent kinases,CDKs)的变化规律,及其可能的调节机制.方法:以急性淋巴细胞白血病Molt-4细胞株为靶细胞,建立Fas介导的细胞周期特异性凋亡模型;采用cyclin/DNA双参数流式细胞术和Western印迹法检测cyclins的表达规律;应用Western印迹法检测CDK1的Thr-161、Tyr-15位点和CDK2的Thr-160位点磷酸化水平的变化.结果:重组人Fas配体(recombinant human Fas ligand,rhFasL)诱导Molt-4细胞的凋亡定位在G1期.在发生细胞凋亡效应前,cyclin D3水平明显升高,而cyclin E水平和CDK2的Thr-160位点磷酸化水平均明显下降;发生凋亡效应后,cyclin D3水平明显下降,而cyclin E水平升高,CDK2 的Thr-160位点磷酸化水平则明显下降,CDK1的Thr-161、Tyr-15位点磷酸化水平稍有下降.Cyclin A和Cyclin B1水平在诱导细胞凋亡过程中无明显变化.Roscovitine在特定浓度(5 μmol/L)下可下调CDK2 Thr-160位点和CDK1 Thr-161位点的磷酸化水平,与rhFasL共同作用后细胞凋亡的发生率明显升高.结论:Fas介导的细胞凋亡具有细胞周期特异性,并始动于晚G1期,是G1期cyclin E/CDK2活性下降以及晚G1期检测点监督的结果;cyclin D3/CDK复合体可能是决定细胞凋亡能否发生的关键.     

丹参酮对人肺癌细胞株的抑制作用及其分子机理

背景与目的观察丹参酮ⅡA对人肺腺癌细胞(SPC-A-1)的抑制作用及其分子机理。方法体外培养的SPC-A-1细胞经无毒剂量(0.5μg/mL)的丹参酮ⅡA处理5天后,观察细胞形态学、增殖动力学、细胞周期分布、细胞凋亡及肿瘤相关基因表达改变,并以全反式维甲酸及顺铂作为对照。结果SPC-A-1细胞经丹参酮ⅡA处理后,细胞生长明显减慢,集落形成率显著降低。FCM细胞周期分析:S期细胞显著减少,G0/G1期细胞则明显增加,细胞凋亡数量显著增加。细胞p53、p21、Fas、Bax表达水平明显升高,而Bcl-2、CDKN2明显降低。结论丹参酮ⅡA对SPC-A-1细胞增殖具有显著抑制作用,其分子机理可能是通过上调p53、p21、Fas、Bax和下调Bcl-2、CKDN2等基因的表达而抑制DNA的合成,同时启动细胞凋亡程序,促进细胞凋亡。     

华蟾素对人乳腺癌细胞株MDA-MB-231生物学特性的影响

目的:探讨华蟾素(cinobufacini)对人乳腺癌细胞株MDA-MB-231增殖、细胞周期和体外侵袭的影响及其可能机制.方法:用CCK-8试剂盒测定并绘制华蟾素作用后MDA-MB-231细胞的生长曲线,FCM法分析细胞周期分布,Transwell小室检测MDA-MB-231细胞的体外侵袭能力, RT-PCR检测细胞周期素(cyclin)及p21 mRNA的表达变化.结果:华蟾素可抑制MDA-MB-231细胞的增殖能力,其半数抑制浓度(half inhibition concentration, IC50)为 0.31 mg/mL,抑制作用随着华蟾素作用时间的延长而增强,与对照组相比差异有统计学意义(P<0.05);Transwell小室检测表明,华蟾素作用后细胞的侵袭能力比对照组明显下降(P<0.05);FCM分析可见,随着华蟾素浓度的增加,停滞于S期的细胞比率比对照组明显增加(P<0.000 1);华蟾素作用后,MDA-MB-231细胞cyclin A1、cyclin D1和cyclin E1 mRNA的表达水平下降, p21 mRNA的表达水平上升,但cyclin B1 mRNA的表达无明显改变.结论:华蟾素通过调控cyclin A1、cyclin D1、cyclin E1和p21的表达而抑制乳腺癌细胞的增殖和侵袭,并影响其细胞周期的分布.     

褪黑素对荷瘤小鼠腹腔巨噬细胞分泌的细胞因子的影响

目的：观察褪黑素（melatonin,MLT)对小鼠移植性肝癌生长的抑制作用及对小鼠腹腔巨噬细胞分泌的细胞因子的影响。方法：建立肝癌小鼠模型，连续2周每日皮下注射MLT，绘制肿瘤生长曲线并采用放射免疫法测定小鼠腹腔巨噬细胞分泌的IL－1β和TNF－α的水平。结果：注射MLT的小鼠肿瘤生长速度明显＜阴性对照组（P＜0．05），腹腔巨噬细胞IL－1β的诱生水平明显提高（P＜0．05），但TNF－α的水平却明显下降。结论：MLT能显著凶制小鼠移植性肝癌的生长，它对荷瘤小鼠的巨噬锚能具有选择性调节作用。     

野生型p53基因与双脱水二乙酰卫矛醇联合诱导肝癌HLE细胞凋亡的研究

背景和目的：p53基因是抑癌基因,研究发现在人类肿瘤中p53基因常发生突变。实验证明野生型p53基因不但抑制肿瘤细胞增殖,而且诱导肿瘤细胞凋亡。但是,单独应用野生型p53基因诱导肿瘤细胞凋亡的作用不很明显。因此,野生型p53基因与药物的联合作用来提高肿瘤细胞凋亡率是目前对肿瘤研究的一新领域。本实验通过转染野生型p53基因联合双脱水二乙酰卫矛醇(1,2：5,6-dianhydro-3,4-diacetylgalactitol,DADAG)作用于肝癌细胞株HLE,研究联合诱导肿瘤细胞的凋亡作用。方法：野生型p53基因通过脂质体Lipofectamine介导转染人肝癌细胞株HLE,同时加入DADAG。96h后,用流式细胞仪、DNA电泳方法进行细胞凋亡分析。结果：流式细胞仪分析细胞凋亡结果：阴性对照组为1．4％、转染pUHD10-3组为3．5％、DADAG处理组为32．6％、转染pUHD10-3-p53组为43．4％、转染p53基因及DADAG处理组为74．6％。DNA电泳发现,转染p53基因及DADAG处理组有到DNA梯形条带。结论：野生型p53基因与DADAG均可诱导人肝癌细胞HLE发生凋亡,转染野生型p53基因与DADAG联合作用,有促进肝癌细胞凋亡的作用。     

Overexpression of cyclin E protein is associated with specific mutation types in the p53 gene and poor survival in human breast cancer

Cyclin E is one of the key regulators of the G(1)/S transition in the cell cycle. Overexpression of cyclin E has been observed in several malignancies and is associated with high proliferation, aberrant expression of other cell cycle regulators and chromosomal instability in vitro. To explore potential associations between cyclin E deregulation and inactivation of the p53 tumor suppressor gene in human breast cancer, we investigated the immunohistochemical expression of cyclin E in paraffin embedded breast cancers from 270 women with known p53 status by cDNA based sequencing of the p53 gene. The breast cancers were divided into three subgroups according to the percentage of cyclin E-positive cells. One hundred and seventy-one patients (63%) had low cyclin E, 72 (27%) medium and 27 (10%) had high cyclin E content. Fifty-six percent (15/27) of the breast cancers with high cyclin E had p53 gene mutations, compared with 14% (24/171) of those with low cyclin E content (P < 0.0001). In p53 mutated breast cancers high cyclin E content was associated with insertions, deletions and nonsense point mutations in the p53 tumor suppressor gene, whereas low cyclin E was linked to p53 missense point mutations. We also observed statistically significant associations between a high cyclin E content and aneuploidy, high S phase, larger tumor size, estrogen receptor negativity, presence of axillary node metastases and high tumor grade. High cyclin E content was associated with poor overall survival in univariate and multivariate analysis (hazard ratio 2.4, 95% confidence interval 1.3-4.5). In summary, our findings demonstrate that overexpression of cyclin E is associated with an aggressive tumor phenotype and specific types of p53 mutations.     

Lack of cyclin E immunoreactivity in non-malignant breast and association with proliferation in breast cancer.

Cyclin E is a G1 cyclin that is essential for the transition from G1 to S phase in the cell cycle. Alterations to cyclin E expression or regulation could be important in tumorigenesis. Previous immunohistochemical and immunoblotting studies have investigated the expression of cyclin E in breast carcinomas. In this study, cyclin E has been investigated in a range of non-malignant and malignant breast using immunohistochemistry. Normal and benign tissue from pre- and post-menopausal women (39 cases), non-involved tissue from cancer-containing breasts (47 cases), ductal carcinoma in situ (22 cases) and invasive breast carcinomas (109 cases) have been examined. There was no reactivity in any of the non-malignant breast. Only one ductal carcinoma in situ contained more than 5% reactive cells. A total of 28% of invasive carcinomas had > 5% of reactive cells (range 0-88% positive cells, mean 12.59%, median 1.0%). A significant association was found with poorer differentiation (P < 0.001), high MIB1 index (P < 0.001), lack of oestrogen receptor (0.05 > P > 0.025) and the presence of p53 protein (0.05 > P > 0.025). Virtually all cases with cyclin E and p53 were poorly differentiated. The presence of cyclin E is therefore only found in breast malignancies and is associated with more aggressive features, including high proliferation.     

The role of p53 in suppression of KSHV cyclin-induced lymphomagenesis

Kaposi's sarcoma-associated herpesvirus (KSHV) encodes a cyclin D homolog, K cyclin, that is thought to promote viral oncogenesis. However, expression of K cyclin in cultured cells not only triggers cell cycle progression but also engages the p53 tumor suppressor pathway, which probably restricts the oncogenic potential of K cyclin. Therefore, to assess the tumorigenic properties of K cyclin in vivo, we transgenically targeted expression of K cyclin to the B and T lymphocyte compartments via the E micro promoter/enhancer. Around 17% of E micro -K cyclin animals develop lymphoma by 9 months of age, and all such lymphomas exhibit loss of p53. A critical role of p53 in suppressing K cyclin-induced lymphomagenesis was confirmed by the greatly accelerated onset of B and T lymphomagenesis in all E micro -K cyclin/p53(-/-) mice. However, absence of p53 did not appear to accelerate K cyclin-induced lymphomagenesis by averting apoptosis: E micro -K cyclin/p53(-/-) end-stage lymphomas contained abundant apoptotic cells, and transgenic E micro -K cyclin/p53(-/-) lymphocytes in vitro were not measurably protected from DNA damage-induced apoptosis compared with E micro -K cyclin/p53(wt) cells. Notably, whereas aneuploidy was frequently evident in pre-lymphomatous tissues, end-stage E micro -K cyclin/p53(-/-) tumors showed a near-diploid DNA content with no aberrant centrosome numbers. Nonetheless, such tumor cells did harbor more restricted genomic alterations, such as single-copy chromosome losses or gains or high-level amplifications. Together, our data support a model in which K cyclin-induced genome instability arises early in the pre-tumorigenic lymphocyte population and that loss of p53 licenses subsequent expansion of tumorigenic clones.     

Mechanisms of proteasome inhibitor PS-341-induced G(2)-M-phase arrest and apoptosis in human non-small cell lung cancer cell lines.

PURPOSE: PS-341 is a novel dipeptide boronic acid proteasome inhibitor with in vitro and in vivo antitumor activity that induces mechanisms of apoptosis by unknown mechanisms. EXPERIMENTAL DESIGN: Human non-small cell lung cancer cell lines were used to investigate effects PS-341 on cell proliferation, cell cycle progression, and the induction of apoptosis. RESULTS: PS-341 was 38-360-fold more cytotoxic against H460 cells when compared with the proteasome inhibitors MG-132 and PSI. Differential PS-341 cytotoxic effects were found with respect to P53 function: H322 cells (p53 mutant) were 6-fold less sensitive as compared with H460 cells (p53 wild type); and H358 cells (p53 null) were 1.6-fold more sensitive as compared with H460 cells (p53 wild type). A concentration- and time-dependent cell cycle blockade at G(2)-M phase was seen for H460 cells without any direct effects on microtubule polymerization or depolymerization. PS-341 exposure in H460 cells led to stabilization of p53, induction of p21(cip/waf-1) and MDM2 expression, an increase in cyclin B and cyclin A, and the activation of cyclin B and cyclin A kinases. MDM2 induction was found only in H460 cells, whereas in H322 and H358 cells, G(2)-M-phase arrest, p21(cip/waf-1) induction, and an increase in cyclin B1 were found. The commitment of G(2)-M-phase cells to apoptosis was verified by the activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase in drug-free medium. CONCLUSIONS: Our data suggest that the PS-341-induced G(2)-M-phase arrest may be associated with the inhibition of degradation of cell cycle regulators and that the up-regulation of p21(cip/waf-1) expression may be via p53-dependent and/or -independent pathways. The resulting disturbance of cell cycle progression leads either to growth inhibition or to the initiation of apoptotic pathways.     

Combined evaluation of expressions of cyclin E and p53 proteins as prognostic factors for patients with gastric cancer.

BACKGROUND: There is a lack of consistency regarding the prognostic value of cyclin E overexpression in gastric cancer (gastric cancer). Our aim was to report on this overexpression and to analyze its correlations with the clinicopathologic variables. Another aim was to examine if aberrant expression of both cyclin E and p53 might increase the malignant potential of gastric cancer. METHODS: Specimens from 89 patients with gastric cancer treated with "curative" intent were evaluated for cyclin E and p53 expressions using immunohistochemical method. The correlations between cyclin E overexpression alone or in combination with p53 expression and the patient's clinicopathologic variables were analyzed. RESULTS: Cyclin E overexpression and p53 expression were shown in 35 (39.3%) and 46 (51.7%) tumors, respectively. The incidence of cyclin E overexpression was significantly higher in deeply invasive cancers (P < 0.0001), in cancers with lymph node metastasis (P = 0.003), and in cancers with advanced stages (P < 0.0001). There were no significant correlations with other clinicopathologic variables. Patients in whom their tumors showed cyclin E overexpression alone or in combination with p53 survived less than patients with negative cyclin E tumors. Multivariate analysis revealed that combined cyclin E overexpression and p53 expression was significantly associated with poor survival after adjusting for other variables (hazard ratio, 3.12; P = 0.009). CONCLUSIONS: Cyclin E overexpression is a common event in gastric cancer. Gastric cancer with cyclin E overexpression exhibit increased aggressiveness in the presence of aberrant p53. The combination of cyclin E overexpression with the p53 expression in gastric cancer further distinguished a subgroup of patients with poor prognosis.     

Prognostic significance of cyclin E and p53 protein overexpression in carcinoma of the renal pelvis and ureter.

Cyclin E gene alteration in the cell cycle plays an important role in carcinogenesis, while p53 protein affects different phase checkpoint pathways by activating p21WAF1/CIP1 in the normal cell cycle. We immunohistochemically examined the expression of cyclin E and p53 proteins in 121 patients with transitional cell carcinoma (TCC) of the renal pelvis and ureter to determine their significance for tumour behaviour and patient prognosis. Cyclin E and p53 immunostaining of the nucleus was observed in 36 tumours (29.8%) and 35 tumours (28.9%) respectively. A significant percentage, 69.4% (25 out of 36 tumours), of the cyclin E-positive tumours exhibited simultaneous labelling for p53 (P < 0.05). Mirror-section technique was performed in five selected double-positive tumours to identify cancer cells that were nuclei positive for both cyclin E and p53. The prevalence of cases simultaneously exhibiting both cyclin E and p53 immunostaining was higher in the high-grade tumours (P < 0.01) than in the other types of tumours. Patients with TCCs coexpressing cyclin E and p53 had a significantly poorer prognosis than those expressing neither cyclin E nor p53 (P < 0.001). These in vivo findings provide evidence for cyclin E protein overexpression in TCCs intimately associated with p53 alteration and suggest that simultaneous overexpression of both cyclin E and p53 is related to tumour behaviour and poor prognosis.     

A mouse model for cyclin E-dependent genetic instability and tumorigenesis

Ubiquitination of murine cyclin E is triggered by phosphorylation on threonine 393. Cyclin E(T393A) knockin mice exhibited increased cyclin E stability, but no phenotypic abnormalities. Importantly, loss of the p53 pathway exacerbated the effect of the T393A mutation. Thus, in p21(-/-) cells the T393A mutation had an exaggerated effect on cyclin E abundance and its associated kinase activity, which caused abnormal cell cycle progression, and genetic instability involving chromosome breaks and translocations. Moreover, cyclin E(T393A) acted synergistically with p53 deficiency to accelerate tumorigenesis in cyclin E(T393A) p53(-/-) mice; Ras more readily transformed cyclin E(T393A) p53(-/-) cells than p53(-/-) cells in vitro; and cyclin E(T393A) mice had a greatly increased susceptibility to Ras-induced lung cancer.     

蛴螬粗提物对人宫颈癌HeLa细胞诱导凋亡作用及其机制

 目的 研究蛴螬粗提物对人宫颈癌HeLa细胞诱导凋亡作用，并探讨其作用机制。方法 采用流式细胞仪检测HeLa细胞的细胞周期分布相和细胞凋亡率；末端脱氧核苷酸转移酶（TdT）介导的脱氧核苷酸缺口末端标记（TdT mediated dUTP nick end labeling）TUNEL法检测凋亡细胞；通过免疫细胞化学SP法测定凋亡相关基因产物p53、Fas、bcl 2、Bax蛋白的表达情况。结果 (1)蛴螬粗提物可以诱导HeLa细胞发生凋亡，加药组出现亚二倍体峰，并且G0/G1期细胞比例显著增加（P＜0.01），而S期和G2/M期细胞比例则明显下降,将细胞阻滞在G0/G1期；（2）蛴螬粗提物作用细胞后凋亡细胞数目随时间延长而增多，凋亡指数与药物处理呈时间依赖性和剂量依赖性；(3)蛴螬粗提物作用后bcl 2、p53蛋白随提取物浓度表达均下降，Bax、Fas蛋白表达上升，四种蛋白表达各组间比较差异均有具有统计学意义（P<0.01）。结论 (1) 蛴螬粗提物对人宫颈癌HeLa细胞具有诱导凋亡作用；(2)蛴螬粗提取物诱导凋亡作用机制可能与细胞周期发生G0/G1期阻滞有关；并且通过下调bcl 2、p53蛋白表达,上调Bax、Fas蛋白表达，经由细胞凋亡的死亡受体通路和线粒体通路完成凋亡的启动和执行。     

细胞周期素E和P53蛋白在胃癌组织中表达及预后意义

目的 :研究细胞周期素E(cyclinE)和P53蛋白在胃癌组织中的表达水平及其与生物学行为和对预后的作用。方法 :应用免疫组化方法检测 1 2 8例胃癌组织中cyclinE和P53蛋白表达水平。 结果 :本组 1 2 8例中 ,cyclinE蛋白阳性 57例 ,占 44 .5 % ;P53蛋白阳性 67例 ,占 52 .3 % ,P53 +/cyclinE +者 48例 ,占 37.5 %。胃癌组织中cyclinE和P53蛋白表达水平与肿瘤大小、浸润深度、局部淋巴结转移、脉管侵犯和远处转移均相关。单因素生存分析显示 ,cyclinE阳性表达组五年生存率 (5 .3 % )显著低于cyclinE表达阴性组 (36 .6 % ,P <0 .0 0 1 ) ,P53蛋白表达阳性的病例五年生存率 (7.8% )显著低于P53表达阴性的病例 (2 2 .6 % ,P <0 .0 0 1 ) ,cyclinE和P53均阳性的病例五年生存率 (2 .3 % ) ,明显低于其他组的病例 (2 7.3 % ,P <0 .0 0 5)。COX模型多因素分析显示 ,cyclinE蛋白表达水平是独立的预后指标 ,P53蛋白表达水平不能作为独立的预后指标。结论 :CyclinE在胃癌中表达具有一定的预后意义 ,P53蛋白在胃癌中表达与肿瘤的生物学行为有关