槲皮素对人乳腺癌裸鼠移植瘤细胞周期的影响

 目的　研究槲皮素对人乳腺癌细胞株MCF 7裸鼠移植瘤细胞周期的影响。方法　 2 4只MCF 7细胞株移植成功的裸鼠分为对照组、槲皮素组、阿霉素组及联合用药组 ,每组 6只。用流式细胞仪分析细胞周期分布 ,用免疫组化测定cyclinD1表达水平。结果　G0 /G1期占细胞周期比例对照组明显低于槲皮素组 ,阿霉素组及联合用药组 (P <0 .0 1) ,S期占细胞周期比例对照组明显高于槲皮素组 ,阿霉素组及联合用药组 (P <0 .0 1) ,cyclinD1表达水平对照组明显高于槲皮素组、阿霉素组及联合用药组 (P <0 .0 1)。结论　槲皮素可作用于MCF 7移植瘤的G1/S节点 ,可抑制移植瘤细胞增殖及cyclinD1表达 ,延缓肿瘤生长。     

细胞周期素D1与乳腺癌

细胞周期中G1－S相的转换是肿瘤细胞增殖的必要条件。细胞周期素（Cyclin)D1则是G1期进展的限速控制因素，故 cyclin D1的表达与乳腺癌的发生发展密切相关。同时cyclin D1在乳腺癌中的表达有助于评价乳腺癌的分期和分级，有助于乳腺癌治疗方案的选择及预后的判断。     

周期蛋白D1在鼻咽癌细胞系中功能及意义的深入研究

目的 深入研究周期蛋白D1在鼻咽癌细胞中的表达特征及生物学功能。以Western blot方法确定D型周期蛋白在鼻咽癌细胞系中的表达谱及表达水平；利用流式细胞术双参数法，确定cyclin D1在鼻咽癌细胞中的表达分布模式；结合反义硫代磷酸化寡聚脱氧核苷酸和抗体剔除实验，分别从mRNA及蛋白质水平抑制、中和cyclinD1的表达，探讨其在鼻咽癌细胞中的生物学功能。结果 在鼻咽癌细胞中，D型周期蛋白的表达谱为D1、D2、D3均表达型，cyclinD1在两株鼻咽癌细胞均有过表达。cyclinD1在鼻咽癌细胞系中的表达呈细胞周期依赖性，在G0／G1期表达最高，S期及G2／M期下降，但仍可检测到。反义cyclinD1硫代磷酸化寡聚脱氧核苷酸和抗体剔除实验可以有效抑制蛋白质表达，抑制细胞进入S期。结论 鼻咽癌细胞系中，D型周期蛋白的表达谱为D1、D2、D3均表达型,cyclinD1在鼻咽癌细胞中有过表达，且表达呈细胞周期依赖性，cyclinD1可能是鼻咽癌细胞G1／S期进行中必不可少的细胞周期调节因子。     

细胞周期蛋白D1在浸润性乳腺癌中的表达及其临床意义

目的　探讨浸润性乳腺癌组织中细胞周期蛋白D 1(cyclinD1)的表达 ,及其与激素受体和临床病理特征的相关性。方法　采用免疫组化方法检测 97例浸润性乳腺癌组织和 2 0例正常乳腺组织中cyclinD1的表达情况 ;采用免疫组化方法检测肿瘤组织中的雌、孕激素受体 (ER、PR)的表达。结果　浸润性乳腺癌组织中 ,cyclinD1蛋白表达率 (5 7.7% )显著高于正常乳腺组织(15 .0 % ) (P <0 .0 1)。ER阳性、PR阳性的乳腺癌组织中cyclinD 1表达较ER阴性、PR阴性者增高。cyclinD 1高表达与腋淋巴结转移、肿瘤大小、TNM分期显著相关 ,而与患者年龄、肿瘤病理类型无关。结论　cyclinD1的高表达在乳腺癌的发生、发展中可能起重要作用 ,并与激素受体、腋淋巴结转移、TNM分期相关     

苦参碱诱导人肝癌细胞分化、凋亡时对 G1细胞周期调节因子的调控

目的：观察苦参碱诱导人肝癌细胞分化、凋亡时,G1细胞周期调节因子的变化,探讨苦参碱对肿瘤细胞增殖的调控。方法：0、0．3、0．8、1．5g/L苦参碱作用HepG2细胞3天,免疫组化检测p53,Rb,p21,p27,p16,cyclinD1蛋白表达：原位杂交检测p53,cyclin D1mRNA的表达。真彩色图像分析对基因表达强弱进行定量。结果用Microsoft-Excel软件统计处理。结果：用药后细胞周期负调控因子p53,Rb,p21,p27,p16表达增强;正调控因子cyclinD1表达减弱。结论：苦参碱诱导人肝癌细胞HepG2分化、凋亡的机制可能与苦参碱上调了G1细胞周期负调节因子的表达,下调了G1期正调节因子cyclinD1表达有关。     

雌二醇联合睾丸酮对乳腺癌MCF-7细胞增殖和凋亡的影响

目的:探讨雌二醇联合睾丸酮对乳腺癌MCF-7细胞增殖和凋亡的影响及其可能机制。方法:将10-10mol/L雌二醇和10-5、10-7、10-9和10-11mol/L睾丸酮单独或联合作用于乳腺癌MCF-7细胞24、48和72h,MTT法检测细胞的生长情况,FCM检测细胞周期和细胞凋亡的情况,以及cyclinD1和雄激素受体(androgen receptor,AR)蛋白的表达情况。结果:雌二醇可促进MCF-7细胞的增殖。高浓度(10-5mol/L)睾丸酮可抑制细胞增殖,并抑制雌二醇促细胞增殖的作用;低浓度(10-9mol/L)睾丸酮可促进MCF-7细胞增殖,并增强雌二醇的促细胞增殖作用。雌二醇联合10-5mol/L睾丸酮作用48h后促使细胞周期由G1期进入S期,细胞凋亡率上升,cyclinD1蛋白的表达上调,AR蛋白的表达未见明显变化。结论:雌二醇联合高浓度睾丸酮可抑制乳腺癌细胞的增殖和促进细胞凋亡,可能与上调细胞cyclinD1蛋白的表达有关。     

EB病毒潜伏膜蛋白LMP1、VEGF和cyclinD1在乳腺癌中的表达及其相关性

目的:探讨乳腺癌中EB病毒(Epstein-Barr virus,EBV)潜伏膜蛋白1(latent membrane protein 1,LMPl)、血管内皮生长因子(vascular endothelial growth factor,VEGF)和细胞周期蛋白D1(cyclinD1)的表达及其相关性.方法:收集乳腺癌标本构建组织芯片,应用免疫组化方法检测LMP1、VEGF和cyclinD1的表达,并结合临床病理因素进行相关分析.结果:乳腺癌组织中LMP1、VEGF及cyclinD1的表达率分别为17.8％(19/107)、85.0％ (91/107)和64.5％ (69/107);LMP1和cyclinD1的表达与患者年龄、肿瘤大小、病理学类型、淋巴结转移及脉管侵犯均无明显相关性(P＞0.05),而两者的表达均与组织学分级有关(P＜0.05);VEGF的表达与患者年龄、肿瘤大小、病理学类型、组织学类型及脉管侵犯均无明显相关(P＞0.05),而与淋巴结转移存在相关性(P＜0.05);LMP1的表达与VEGF和cyclinD1均明显相关(P＜0.05),同时,VEGF与cyclinD1表达明显相关(P＜0.05).结论:乳腺癌中LMP1可能直接上调VEGF的表达,或者LMP1通过促进cyclinD1的表达来上调VEGF的表达,从而对乳腺癌的淋巴转移及发生发展起到促进作用.     

P27及细胞周期素D1在子宫内膜癌中的表达及意义

目的探讨p27蛋白及细胞周期素D1(cyclinD1)在子宫内膜癌中的表达及意义。方法采用免疫组化SP法检测42例子宫内膜癌中p27蛋白及cyclinD1的表达。结果子宫内膜癌p27蛋白的核表达率为16.7%,明显低于对照组(正常子宫内膜及非典型增生子宫内膜),cyclinD1的核表达率为40.5%,明显高于对照组;p27和cyclinD1表达均与子宫内膜癌的细胞学分级及临床分期有关(P<0.05);p27核低表达合并cyclinD1阳性高表达出现在分化差及手术病理分期高的病例。结论p27蛋白核表达的降低及cy-clinD1蛋白核表达增高与子宫内膜癌的发生发展相关,联合检测p27、cyclinD1蛋白有助于估计预后,指导治疗。     

p27、cyclin D1与恶性肿瘤

细胞周期调控紊乱是恶性肿瘤发生、发展的主要原因之一,其中,蛋白p27与cyclin D1在细胞周期调控中发挥了重要作用.p27与cyclinD1是细胞周期正负调控因子.p27蛋白在多数肿瘤中低表达或不表达,而cyclinD1蛋白多呈高表达,它们与恶性肿瘤的发生、发展关系密切.目前细胞周期及其调控机制与肿瘤的关系已成为研究热点.     

乳腺癌中cyclinD2 、CDK4 的表达及其临床意义

 目的 研究乳腺癌组织中细胞周期蛋白D2（cyclinD2）、细胞周期蛋白依赖性激酶4（cyclin-dependentkinase4,CDK4）的表达,探讨它们与p27^kip1蛋白表达、与临床病理指标的关系及其预后意义。方法 应用免疫组化SP法,检测96例乳腺癌、18例癌旁正常乳腺组织石蜡切片中cyclinD2、CDK4的表达,比较它们与p27 ^kip1蛋白表达、与临床病理学指标之间的关系。结果 ①96例乳腺癌组织中cyclinD2、CDK4和p27^kip1表达率分别为41.7％、54．2％和38．5％,与正常乳腺组织相比有显著性差异（P〈0．001）。②cyclinD2、CDK4的表达与乳腺癌的组织学分级,核分裂数有关（P〈0．001）,和局部复发有关（P〈0．05）,而与患者年龄、肿瘤大小、组织类型无关（P〉0．05）,CDK4的表达与乳腺癌的淋巴结转移,雌激素受体状态也有密切关系（P〈0．01）。③p27^kip1的表达缺失,与肿瘤大小、组织学分级,核分裂数,有无淋巴结转移以及局部复发均有关系（P〈0．05）,而且p27 ^kip1的表达与eyelinD2、CDK4的表达呈显著负相关（P〈0．叭）。结论 cyclinD2和CDK4的表达与乳腺癌的发生、发展有关,而p27 ^kip1的表达缺失和CDK4的异常表达与乳腺癌的侵袭、转移及复发有关,可作为判断乳腺癌生物学行为和预后的重要指标。     

Knockdown of the Bmi-1 oncogene inhibits cell proliferation and induces cell apoptosis and is involved in the decrease of Akt phosphorylation in the human breast carcinoma cell line MCF-7

It is well documented that B cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1), widely overexpressed in the vast majority of malignancies, plays an essential role in the occurrence and development of several different tumors. Here, we report Bmi-1 siRNA-mediated cell proliferation inhibition and cell apoptosis in vitro and in vivo in the human breast carcinoma cell line MCF-7. Our results demonstrated that Bmi-1 siRNA effectively down-regulated the expression of Bmi-1, inhibited cell proliferation in vitro and in vivo, evoked cell cycle arrest in the G0/G1 phase and induced cell apoptosis in MCF-7 cells, coupled with decrease in cyclin D1, cyclin E, cdk2, bcl-2 and Ki-67 expression and Akt phosphorylation levels and an increase of p21 and bax expression and activities of caspase-3/-9. Taken together, our results suggest that Bmi-1 may be a potential molecular target for the therapy of breast carcinoma.     

CCND1 polymorphisms (A870G and C1722G) modulate its protein expression and survival in oral carcinoma

Cyclin D1 is an essential regulator of the G1 phase of the cell cycle progression and plays an important role in the transition of the cell from the G1 phase to the S phase of the cell cycle. Overexpression of cyclin D1 is a frequently observed feature of human cancers of diverse histological origin. Recently, we have reported overexpression of cyclin D1 in oral carcinoma. However, the underlying mechanism leading to this aberrant expression remains poorly understood. In this study, we have investigated the role of CCND1 A870G and C1722G polymorphisms on cyclin D1 expression and prognosis in a relatively homogenous population of 178 oral squamous cell carcinoma patients by PCR-SSCP, RFLP, RT-PCR and immunohistochemical methods. Genotype frequencies of both the polymorphisms were conformed to Hardy-Weinberg equilibrium. CCND1 A870G (p=0.004) and C1722G (p=0.012) polymorphisms were significantly associated with cyclin D1 expression. Kaplan-Meier estimates revealed that CCND1 genotypes A870G 'GG' (p=0.012) and C1722G 'CC' (p=0.021) could predict the poor survival of the patients. In multivariate analysis, CCND1 A870G genotype combination (p=0.024, HR - 1.74 (1.08-2.81)) and cyclin D1 expression (p=0.025, HR - 1.72 (1.07-2.77)) were independent predictors of survival in this patient cohort. Our results thus demonstrate, CCND1 polymorphisms stand-in as cis-acting regulatory elements modulating its expression and cyclin D1 genotype and phenotype could provide valuable additional information regarding prognosis of oral cancer patients.     

Cyclin D1 overexpression enhances radiation-induced apoptosis and radiosensitivity in a breast tumor cell line

Overexpression of cyclin D1, a G1 cell cycle regulator, is often found in many different tumor types, such as breast carcinoma and squamous cell carcinoma of the head and neck. The overexpression of this protein is, in several cases, associated with a poor prognosis. In this study, the effect of cyclin D1 on radiosensitivity was investigated in a breast tumor cell line, MCF7, containing a cyclin D1 gene construct under the control of a tetracycline-sensitive regulator. MCF7 cells cultured without tetracycline resulted in a 6-fold increase in the cyclin D1 protein. Cyclin D1-overexpressing MCF7 cells were more sensitive to ionizing radiation than the nonoverexpressing counterparts. The cyclin D1-overexpressing cells also exhibited a higher induction of apoptosis. Treatment with a dose of 5 Gy resulted in a rapid increase of p53 and p21 in the cyclin D1-overexpressing cells. Nonoverexpressing cells showed a more transient expression of these proteins after ionizing radiation. A pronounced G2-M block was observed in both cell lines. The cyclin D1-overexpressing cells were, however, released earlier from the block than the control cells. These data suggest that overexpression of cyclin D1 alters sensitivity toward ionizing radiation by modulating gamma-radiation-induced G2-M transition.     

Cyclins and breast cancer

Cyclins are regulatory subunits for cyclin dependent kinases in the coordination of the cell cycle. Cyclins can also serve non-cell cycle functions, such as the transactivation of estrogen receptor by cyclin D. Evidence for the participation of the G1 cyclins D and E in breast cancer is summarized, including transgenic and knockout mice, transfections, and expression patterns in cohort studies. Overexpression of cyclin D has been reported in ductal carcinoma in situ (DCIS), and similar overexpression of cyclin E is suggested. Strategies to reduce cyclin expression are discussed as potential prevention efforts.     

Cytologic evaluation of cyclin D1 expression in primary breast carcinoma

BACKGROUND: Preoperative assessment of the biologic characteristics of primary breast carcinoma is important because neoadjuvant medical therapy is being used increasingly. In the current study, the authors attempted to evaluate the validity of cyclin D1 assay in fine-needle aspiration (FNA) samples from patients with primary breast carcinoma. METHODS: FNA samples were obtained prior to therapy and multiple slides were stored at -80 degrees C for subsequent immunocytochemical analysis (ICA). ICA for cyclin D1 protein was performed on FNA samples from 51 breast carcinoma patients and 20 samples from patients with benign breast disease. In 45 breast carcinoma patients who had undergone surgery, sections were taken from paraffin blocks and stained by ICA for cyclin D1 validation. Possible correlations between cyclin D1 expression in the FNA samples and the biologic data of the patients also were analyzed. RESULTS: Cyclin D1 expression was detected in 37 FNA samples from 51 breast carcinomas (72.5%) whereas expression of cyclin D1 was detected in 8 FNA samples from 20 patients with benign breast disease (40%). In histologic sections after surgery, 26 cases of breast carcinoma (65%) showed a positive reaction to cyclin D1. Concordance for the presence of cyclin D1 between FNA samples and histologic samples was 75%. Cyclin D1 expression was high in patients with the tumors that expressed estrogen receptor (ER) (30 of 34 vs. 5 of 11; P = 0.028) and progesterone receptor (PR) (33 of 38 vs. 2 of 7; P = 0.007). There was no significant relation found between cyclin D1 expression and tumor size or lymph node metastasis. Cyclin D1 expression within invasive ductal carcinoma was observed in > 80% of low or intermediate nuclear grade tumors but its expression decreased to 61.5% (8 of 13 cases) in tumors with high nuclear grade (P = 0.023). All 14 breast carcinomas in which the S-phase fraction was 15% showed cyclin D1 expression. Cyclin D1 expression was found to be correlated inversely with proliferative activity in breast carcinoma (P = 0.023). CONCLUSIONS: The results of the current study show that cyclin D1 expression can be measured by ICA in FNA samples with reasonable concordance with the results of histologic section. Cyclin D1 expression was found to be associated with ER/PR status and cell differentiation. The results of the current study indicate that the measurement of novel molecular markers could be performed adequately in FNA samples as well as in histologic sections.     

Expression pattern of ATM and cyclin D1 in ductal carcinoma, normal adjacent and normal breast tissues of Iranian breast cancer patients

ATM protein kinase plays a critical role in maintaining genome integrity by activating a biochemical chain reaction that in turn leads to cell cycle checkpoint activation and repair of DNA damage. Cyclin D1 acts in regulating the G1 phase of the cell cycle. Experimental and clinical studies suggest them to be involved in transformation and tumour progression. To elucidate the role of ATM and cyclin D1 expression in sporadic breast cancer, we investigated the possible link between their RNA expression levels in ductal carcinoma and normal adjacent versus normal breast tissues measured by Taqman real-time PCR in 119 breast tissues. Results showed that cyclin D1 over-expressed in 51.4% of breast tumours, whereas ATM expression was down regulated in 55% of breast tumours compared to both normal adjacent and normal controls (P ≤ 0.01). Cyclin D1 expression in adjacent normal and normal tissues was not significantly differed, whereas ATM expression in normal adjacent was lower than normal control (P ≤ 0.01). Over-expression of cyclin D1 correlated with ER(+) and/or PR(+) (oestrogen/progesterone receptor) status, whereas it mostly under-expressed in HER2(+) (human epidermal growth factor 2) tumours. ATM under-expression was more observed in triple-negative tumours (ER(-), PR(-) and HER2(-)). Our results indicated that reduced expression of the ATM and aberrant cyclin D1 expressions may contribute to the development and/or malignant progression of breast carcinomas also the latter could be involved in the regulation of hormone sensitivity associated with ER and PR.     

MiR-210 regulates cell cycle in nasopharyngeal carcinoma cell line （CNE-1） under hypoxic condition by reducing the expression of cyclin DI

Objective： The aim of our study was to determine the underlying mechanism of miR-210 on regulation of the cell cycle in nasopharyngeal carcinoma cell line CNE-1, particularly through regulation of cyclin D1, under hypoxic conditions. Methods： The CNE-1 cell line was induced with hypoxia, and the expression levels of endogenic miR-210 and cyclin D1 were detected by real-time PCR and Western blotting. Next, the luciferase assay was used to confirm that cyclin D1 is a target gene for miR-210. Cell cycle and cell proliferation were detected in CNE-1 cells that were cultured under hypoxic conditions with either overexpression or knockout of miR-210 using flow cytometry and MTT assay, respectively. Results： Hypoxia induced the expression of miR-210, resulting in reduced mRNA and protein levels of cyclin D1 and repression of cyclin D1 in CNE-1 cells. Further analysis indicated that miR-210 directly binded to the 3＇UTR of the cyclin D1 gene, thus regulated the expression of cyclin DI. The flow cytometry assay showed that, under hypoxic conditions, miR-210 blocked CNE-1 cells in the G1 phase, and miR-210 also inhibited the proliferation of CNE-1 cells. Conclusion： Under hypoxic conditions, miR-210 directly reduced the expression of cyclin D1, leading to CNE-1 cells blocked in G1 phase.