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1.
Millimeter waves, high-frequency electromagnetic waves, can effectively alleviate the clinical symptoms in osteoarthritis patients, as a non-pharmaceutical and non-invasive physical therapy regimen. However, the molecular mechanisms of the therapeutic effects of millimeter wave treatment are not well understood. In the present study, the effect of millimeter waves on the G1/S cell cycle progression in chondrocytes and the underlying mechanism was investigated. Chondrocytes isolated from the knee of SD rats were cultured and identified using toluidine blue staining. The second generation chondrocytes were collected and stimulated with or without millimeter waves for 48 h. Chondrocyte viability was analyzed using the MTT assay. The cell cycle distribution of chondrocytes was analyzed by flow cytometry. mRNA and protein expression levels of cyclin D1, cyclin-dependent kinases 4 and 6 (CDK4 and CDK6) and p21 were detected using real-time PCR and western blotting, respectively. Millimeter wave stimulation was found to significantly enhance chondrocyte viability. Moreover, the percentage of chondrocytes in the G0/G1 phase was significantly decreased, whereas that in the S phase was significantly increased. In addition, following millimeter wave treatment, cyclin D1, CDK4 and CDK6 expression was significantly upregulated, whereas p21 expression was significantly downregulated. The results indicate that millimeter wave treatment promotes chondrocyte proliferation via cell cycle progression.  相似文献   

2.
目的:探讨小檗碱联合表柔比星对膀胱癌T24细胞周期的影响及相关作用机制。方法:实验将膀胱癌T24细胞分为4组:对照组、表柔比星组、表柔比星+小檗碱组和小檗碱组,采用MTT法检测细胞的活力,检测药物处理后对膀胱癌T24细胞增殖的抑制情况。用流式细胞术分析T24细胞周期分布并用Western blot法测定cyclin D1、CDK2、CDK4、P21和P27蛋白的表达水平。结果:小檗碱联合表柔比星显著抑制T24细胞的活力,存在时间依赖性,联合用药组的G_0/G_1期细胞比例增高,S期和G_2期细胞比例降低,与单用药物组及对照组比较有显著性差异(P0.05)。联合用药上调细胞周期依赖性激酶抑制蛋白P27和P21蛋白的表达水平,同时下调cyclin D1、CDK2及CDK4细胞周期蛋白的表达水平。结论:小檗碱增强表柔比星对膀胱癌T24细胞增殖的抑制及G_0/G_1期阻滞,其作用机制可能与上调P27及P21蛋白和抑制cyclin D1、CDK2及CDK4蛋白表达有关。  相似文献   

3.
Mefloquine (MQ), an analog of chloroquine, exhibits a promising cytotoxic activity against carcinoma cell lines and for the treatment of glioblastoma patients. The present study demonstrates the effect of mefloquine on proliferation and cell cycle in chondrocytes. MTT assay and propidium iodide staining were used for the analysis of proliferation and cell cycle distribution, respectively. Western blot analysis was used to examine the expression levels of cyclin B1/cdc2, cdc25c, p21WAF1/CIP1 and p53. The results revealed that mefloquine inhibited the proliferation of chondrocytes and caused cell cycle arrests in the G2/M phase. The proliferation of chondrocytes was reduced to 27% at 40 μM concentration of mefloquine after 48 h. The population of chondrocytes in G2/M phase was found to be 15.7 and 48.4%, respectively at 10 and 40 μM concentration of mefloquine at 48 h following treatment. The expression of the cell cycle regulatory proteins including, cyclin B1/cdc2 and cdc25c was inhibited. On the other hand, mefloquine treatment promoted the expression of p21WAF1/CIP1 and p53 at 40 μM concentration after 48 h. Therefore, mefloquine inhibits proliferation and induces cell cycle arrest in chondrocytes.  相似文献   

4.
 目的:研究星形细胞上调基因1(astrocyte elevated gene-1,AEG-1)在人宫颈鳞癌细胞和组织中的表达,探讨AEG-1表达下调对宫颈癌SiHa细胞细胞周期和侵袭能力的影响,并分析其可能的分子机制。方法:采用Western blotting检测正常宫颈组织、宫颈鳞癌组织、HeLa、SiHa和CaSki细胞中AEG-1蛋白的表达。将对照siRNA和AEG-1 siRNA分别转染SiHa细胞,利用Western blotting检测SiHa细胞中AEG-1蛋白的表达,采用流式细胞术检测细胞周期分布的变化,采用Boyden小室检测细胞侵袭能力的变化,最后采用Western blotting检测cyclin D1、细胞周期素依赖性激酶 2(CDK2)和基质金属蛋白酶9(MMP-9)蛋白表达的变化。结果:宫颈鳞癌组织中AEG-1蛋白表达显著高于正常宫颈组织(P<0.05),同时3株宫颈癌细胞中AEG-1蛋白表达均显著高于正常宫颈组织,其中SiHa细胞中AEG-1蛋白表达最高(P<0.05)。此外,AEG-1 siRNA能显著下调SiHa细胞中AEG-1蛋白的表达(P<0.05),其表达下调能明显促使SiHa细胞在G0/G1期的比例增加和降低其侵袭能力。Western blotting结果表明,AEG-1 siRNA组中cyclin D1、CDK2和MMP-9蛋白的表达均显著低于未处理组和对照siRNA组(P<0.05)。结论:AEG-1在宫颈癌中的高表达可能与宫颈癌的发生发展密切相关,其表达下调介导的细胞周期静止和侵袭能力降低可能与cyclin D1、CDK2和MMP-9蛋白表达下调密切相关。  相似文献   

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6.
目的:探讨沉默HeLa细胞的ClC-3氯通道基因后细胞周期分布的变化及其作用机制。方法:依照siRNA设计原则构建沉默ClC-3基因的ClC-3 siRNA并转染HeLa细胞;实验分为空白对照组(control组)、转染试剂对照组(Lipo组)、阴性对照组(negative siRNA组)和ClC-3 siRNA组。采用real-time PCR检测ClC-3 siRNA的沉默效率;流式细胞术检测细胞周期分布情况;Western blot检测ClC-3蛋白及相关细胞周期蛋白(cyclin)D1、细胞周期蛋白依赖激酶(cyclin-dependent kinase,CDK)4、CDK6、P21和P27等表达。结果:CIC-3 siRNA成功沉默HeLa细胞的ClC-3基因。和其它组相比,ClC-3 siRNA组的细胞周期被阻抑在G_0/G_1期。CIC-3 siRNA组的cyclin D1、CDK4和CDK6蛋白表达水平明显下降,P21和P27蛋白表达水平明显上升。结论:沉默HeLa细胞ClC-3氯通道基因可影响cyclin D1、CDK4、CDK6、P21和27蛋白的表达水平胆抑HeLa细胞周期停滞在G_0/G_1期。  相似文献   

7.
目的:研究小檗碱(berberine,Ber)增强丝裂霉素C(mitomycin C,MMC)诱导的人类膀胱癌T24细胞周期阻滞和细胞凋亡的作用及其相关机制。方法:将T24细胞分为4组:对照组、MMC组、MMC+Ber组和Ber组;采用CCK-8法检测不同药物处理后T24细胞的活力;采用流式细胞术分析不同药物处理后T24细胞周期的情况;Western blot检测细胞周期调控相关蛋白及凋亡相关蛋白的表达;Annexin V-FITC/PI双染后用流式细胞术检测各组细胞凋亡率。结果:CCK-8实验表明Ber能增强MMC抑制T24细胞活力的作用;流式细胞术检测细胞周期结果显示,MMC+Ber组T24细胞滞于G_0/G_1期(P0.05);与MMC组相比,MMC+Ber组p21和p27的蛋白表达上调(P0.05),cyclin D1、CDK2和CDK4的蛋白表达下调(P0.05),同时Ber促进MMC下调survivin的蛋白表达(P0.05);Annexin V-FITC/PI双染结果显示,Ber能促进MMC诱导的T24细胞凋亡(P0.05)。结论:Ber能显著增强MMC抑制T24细胞活力的作用,其机制可能是通过上调p21和p27,进而抑制cyclin D1、CDK2和CDK4表达;同时通过抑制survivin蛋白的表达,最终导致细胞被阻滞在G_0/G_1期,并促进细胞凋亡。  相似文献   

8.
RN181, a RING finger domain-containing protein, is an E3 ubiquitin ligase. However, its biological function and clinical significance in cancer biology are obscure. Here, we report that RN181 expression is significantly down-regulated in 165 tumour tissues of gastric carcinoma (GC) versus adjacent non-tumour tissues, and inversely associated with tumour differentiation, tumour size, clinical stage, and patient's overall survival. Alterations of RN181 expression in GC cells by retrovirus-transduced up-regulation and down-regulation demonstrated that RN181 functions as a tumour suppressor to inhibit growth of GC in both in vitro culture and in vivo animal models by decreasing tumour cell proliferation and increasing tumour cell apoptosis. Cell cycle analysis revealed that RN181 controls the cell cycle transition from G1 to S phase. Mechanistic studies demonstrated that RN181 inhibits ERK/MAPK signalling, thereby regulating the activity of cyclin D1–CDK4, and consequently controlling progression in the cell cycle from G1 to S phase. Restoring CDK4 in GC cells rescued the inhibitory phenotype produced by RN181 in vitro and in vivo, suggesting a dominant role of CDK4 in control of the tumour growth by RN181. Importantly, RN181 expression is inversely correlated with the expression of cyclin D1 and CDK4 in GC clinical samples, substantiating the role of the RN181–cyclin D1/CDK4 pathway in control of the tumour growth of GC. Our results provide new insights into the pathogenesis and development of GC and rationale for developing novel intervention strategies against GC by disruption of ERK/MAPK–cyclin D1/CDK4 signalling. In addition, RN181 may serve as a novel biomarker for predicting clinical outcome of GC. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   

9.
Coumarins induce apoptosis by activating mitochondrial pathway and caspase-3-dependent apoptotic pathway. In the present study, we first time investigated the effect of 3-cinnamoyl-4-hydroxy-6-methyl-2H-pyran-2-one (CHP) on induction of apoptosis in human ovarian carcinoma cells. The data from MTT assay revealed a significant inhibitory effect on cell viability at 30 (87%) and 50 μM (74%) concentration of CHP in OVCAR-3 and OVCAR-420 cells, respectively after 72 h. Apoptosis analysis using annexin V/PI double staining followed by flow cytometry showed 59 and 52% binding to annexin V-FITC in OVCAR-3 and OVCAR-420 cells respectively. propidium iodide (PI) staining and flow cytometry examination indicated a significant increase in percentage of cells in G2/M phase after treatment with CHP compared to DMSO control group. Reactive oxygen species (ROS) assay kit showed increase in levels of ROS. We used rhodamine-123 (Rh-123) staining and flow cytometry assay to determine changes in mitochondrial membrane potential (ΛΨm). The results revealed that CHP significantly decreased MMP to 85.65 ± 1.2443% & 49.78 ± 1.6554% at 10 and 30 μM respectively in OVCAR-3 compared to 95.97 ± 2.1243% in control group. Western blot analysis clearly indicated a significant increase in the expression of Caspase-3, Bax, and release of Cytochrome c and decrease in Bcl-2, CDK1 and Cyclin B1 expression on treatment with CHP. Therefore, CHP may become a potential candidate for the treatment of human ovarian cancers.  相似文献   

10.
Cell cycle regulation depends on a fine balance between cyclins, cyclin-dependent kinases (CDKs), and cyclin-dependent kinase inhibitors (CKIs) that block the cycle progression. Alterations of the cell cycle regulators are a common feature of many malignant tumors, and some have been shown to have prognostic significance. In this study, 152 cases of different types of soft tissue sarcomas were evaluated for alterations of cell cycle regulator proteins that control the cell cycle progression from G1 to S phase and govern the Rb pathway. Immunohistochemical stains for proteins Rb, E2F1, cyclin D1, CDK4, CDK6, p16, and p27 were carried out on tissue microarrays. The relationship between the expression of these proteins and the histologic grade of the sarcomas was assessed. Altered expression for Rb and p16 proteins was identified in 67.8% and 65.1% of the cases, respectively. Overexpression of E2F1, cyclin D1, CDK4, and CDK6 was detected in 50.7%, 24.3%, 92.1%, and 10.5%, respectively. Overexpression of E2F1 was associated with altered expression of Rb protein. Overexpression of cyclin D1, CDK4, and CDK6 showed an association with normal Rb expression. CDK6 expression revealed a positive correlation with the histologic grade of the sarcoma, and p27 expression was inversely correlated with sarcoma grade. These results suggest that alterations of the Rb pathway proteins are common in soft tissue sarcomas and may participate in their tumorigenesis. CDK6 and p27 showed correlation with the histologic grade of the sarcomas, suggesting that these proteins could be used as prognostic markers.  相似文献   

11.
目的:探讨三丁基过氧化氢(t-BHP)诱导WI-38细胞衰老的细胞周期调控机制。方法: 从30代开始,隔代用t-BHP作用WI-38细胞4次,每次1 h,诱导细胞衰老,从细胞超微结构、细胞周期分析和β-半乳糖苷酶细胞化学染色观察衰老细胞的特点,同时用Western blotting方法检测细胞周期调控蛋白CDK4、CDK2、cyclin D1、cyclin E 、p21和p16的表达程度。 结果:100 μmol/L t-BHP作用4次后,WI-38细胞出现衰老的特征,细胞增殖分裂停止,细胞体积增大、胞体变平、次级溶酶体增多,同时G1期细胞比例增加,β-半乳糖苷酶染色阳性细胞数增加,提示t-BHP能有效地诱导细胞衰老。t-BHP作用后CDK4、CDK2、cyclin E 表达下降,cyclin D1、p21和p16表达增加。 结论: t-BHP有诱导细胞衰老的作用,其机制可能与通过调节细胞周期调控分子的表达有关。  相似文献   

12.
Herpes simplex virus type 1 (HSV-1) infection disrupted cell cycle regulation in at least two ways. First, infection of quiescent human embryonic lung cells simultaneously with readdition of serum caused inhibition of cyclin D/cyclin-dependent kinase (CDK) 4,6-specific and cyclin E/CDK2-specific phosphorylation of the retinoblastoma protein pRb. The inhibition of cyclin D/CDK4,6 kinase activity corresponded to a loss of cyclin D1 protein and a failure of CDK4 and CDK6 to translocate to the nucleus. Failure to detect cyclin E/CDK2 kinase activity was accompanied by a loss of cyclin E protein and a failure of CDK2 to translocate to the nucleus. Levels of pocket protein p130 persisted, whereas p107 did not accumulate. As a result of these effects on cyclin kinase, G(0)-infected cells failed to reenter the cell cycle. The second type of HSV-induced cell cycle dysregulation was observed in asynchronously dividing cell cultures. A rapid inhibition of preexisting cyclin E/CDK2 and cyclin A/CDK2 activities was observed in human embryonic lung cells, as well as two other human cell lines: C33 and U2OS. HSV-1 immediate-early gene expression was necessary for the inhibition of CDK2 kinase activity. Cyclin and CDK subunit protein levels, intracellular localization, and complex stability were unaffected by infection. In addition, levels of cyclin-dependent kinase inhibitors, p27 and p21, were not affected by HSV-1. Previous experiments demonstrated that in asynchronous infected cells, hypophosphorylated pRb and pocket protein-E2F complexes accumulated, and cellular DNA synthesis was rapidly inhibited. Coupled with the present results, this indicates that HSV-1 has evolved mechanisms for preventing cells in G(1) from proceeding through the restriction point and for cells in S from completing a round of DNA replication.  相似文献   

13.
目的:探讨哺乳动物雷帕霉素靶蛋白(mTOR)激酶抑制剂CC-223对乳腺癌细胞增殖的抑制作用及其相关分子机制。方法:CCK-8法检测CC-223对人乳腺癌细胞MCF-7和MDA-MB-231细胞活力的抑制作用;流式细胞术分析CC-223对乳腺癌细胞周期的影响;Western blot实验检测CC-223对细胞周期调控相关蛋白及细胞增殖相关蛋白c-Myc和存活蛋白(survivin)表达的影响。结果:CCK-8结果表明,CC-223能够显著抑制MCF-7细胞和MDA-MB-231细胞活力(P<0.05);流式细胞术实验结果显示,CC-223能够诱导MCF-7细胞发生G 1期和G 2/M期阻滞(P<0.05);较低浓度的CC-223诱导MDA-MB-231细胞周期阻滞于G 2/M期(P<0.05),而处于G 1期的细胞数量无显著差异。CC-223处理乳腺癌细胞24 h后,细胞周期蛋白B1、细胞周期蛋白D1表达和细胞分裂周期蛋白2(Cdc2)磷酸化水平显著降低(P<0.05)。Western blot结果表明,MCF-7和MDA-MB-231细胞经CC-223作用后,c-Myc和survivin的表达水平显著下调(P<0.05)。结论:CC-223能够抑制乳腺癌细胞活力,阻滞细胞周期进程,同时下调乳腺癌细胞中c-Myc与survivin的蛋白表达。  相似文献   

14.
目的:观察地西他滨(DAC)抑制白血病K562细胞生长和诱导分化的作用。方法:不同浓度的DAC处理K562细胞。MTT法和半固体集落生成实验检测K562细胞增殖能力;瑞氏染色观察细胞形态;流式细胞术检测分化相关抗原CD11b和CD42b阳性表达率;Western blot检测细胞周期蛋白依赖性激酶2(CDK2)、细胞周期蛋白E1(cyclin E1)、细胞周期负调控因子P27、红系分化核转录因子GATA-1及粒系分化核转录因子PU.1蛋白的表达水平。结果:DAC能够减少K562细胞集落形成的数量,降低细胞活力,减少核质比,抑制K562细胞进入S期,并阻滞在G_2/M期,提高分化相关抗原CD11b和CD42b阳性表达率,上调P27、GATA-1和PU.1蛋白表达,同时下调CDK2和cyclin E1蛋白表达。结论:DAC可能通过调控细胞周期抑制K562细胞增殖,同时诱导多向分化。  相似文献   

15.
Hsp90α (heat shock protein 90α), one of the important molecular chaperones in cancer cell signal transduction, has been a new candidate target for cancer therapy. Cyclin B1, the client protein of Hsp90α, plays a key role as a mitotic cyclin in the G2-M phase transition during the cell cycle progression. However, the relationship between the level of HSP90α and cyclin B1, the location of Hsp90α and cyclin B1 in prognosis of esophageal squamous cell carcinoma (ESCC) has not been examined. Here, we demonstrate that the diagnostic significance of Hsp90α and cyclin B1 by immunohistochemistry and the association of Hsp90α and cyclin B1 expression in ESCC. In the specimens from 105 ESCC patients (81 stained with Hsp90α antibody by Immunohistochemistry, 65 with cyclin B1 antibody, and among them, 41 paired specimens were stained with Hsp90α and cyclin B1 respectively, and then checked for the correlation of the level and location of Hsp90α and cylcin B1. The positivity rate of Hsp90α and cyclin B1 expression were 96.3% (78 of 81) and 84.6% (55 of 65) respectively. Both of them, the expression levels are associated with the clinical pathological stage (Hsp90α, p=0.027; cyclin B1, p=0.007). No association was found between Hsp90α or cyclin B1 and gender, age, tumor location. As to TMN stage, there is no association with the level of Hsp90α, However, cyclin B1 expression is significantly related to tumor status (p=0.002). Interestingly, Hsp90α expression was negatively correlated to cyclin B1 expression (Gamma=-0.692, p=0.007) in the keratin pearls though there is a positive correlation in the other areas of tumor (Gamma=0.503, p=0.015), which suggest Hsp90α might play diverse roles in the cyclin B1 expression and cyclin B1 related cell cycle regulation in the different area of tumor. These findings demonstrated that the expression of Hsp90α, cyclin B1 protein is associated with tumor malignancy and prognosis for patients with human esophageal squamous cell carcinoma, and Hsp90α might be involved in cyclin B1 expression regulation and cell cycle regulation in keratin peal formation of ESCC.  相似文献   

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17.
目的探讨转录因子环磷酸腺苷反应元件结合蛋白(CREB)在紫杉醇诱导宫颈腺癌HeLa细胞周期阻滞中的作用及其分子机制。方法 MTT法确定紫杉醇的最佳浓度和处理时间;PCR技术构建pCI neo/CREB(PN)重组质粒及pCI neo/CREB-M(PM)定点突变质粒;流式细胞术检测细胞周期,Western blotting检测磷酸化CREB(pCREB)、CREB、cyclins以及CDKs蛋白表达。结果紫杉醇抑制HeLa细胞增殖的有效条件为0.1μmol/L处理24 h。0.1μmol/L紫杉醇诱导G2/M细胞数量增加,并呈时间依赖性;cyclin A表达量下调,cyclin B1、D1和pCREB表达量上调。此外,紫杉醇的处理对cyclin E、CDK1、CDK2、CDK4和CREB表达量并无显著性改变。然而,PM联合紫杉醇处理后显著性地反转了紫杉醇单独处理引起的cyclin A下调、cyclin B1和cyclin D1的上调,并且细胞周期G2/M期阻滞显著性减少。结论转录因子CREB介导的靶向细胞周期蛋白表达在紫杉醇诱导的细胞周期阻滞过程中扮演重要角色。  相似文献   

18.
目的:探讨蛇六谷提取物(TuAKe)抑制人慢性髓系白血病K562细胞增殖和诱导分化的作用机制。方法:不同浓度的TuAKe处理K562细胞,MTT比色法和半固体集落形成实验检测K562细胞的增殖能力;瑞氏-姬姆萨染色观察细胞形态;流式细胞术检测分化相关抗原CD11b、CD14和CD42b的阳性表达率;Western blot法检测细胞周期蛋白依赖性激酶2(CDK2)、细胞周期蛋白E1(cyclin E1)和红系分化核转录因子GATA-1的蛋白表达水平。结果:TuAKe能够抑制K562细胞增殖,改变细胞形态,抑制K562细胞进入S期,并阻滞在G_2/M期,提高分化相关抗原CD11b、CD14和CD42b阳性表达率,上调GATA-1蛋白表达,同时下调CDK2和cyclin E1蛋白表达(P0.05)。结论:TuAKe可能通过调控细胞周期抑制K562细胞增殖,同时诱导K562细胞多向分化。  相似文献   

19.
The proliferation of eukaryotic cells is primarily regulated by a decision made during the G1 phase of the cell cycle as to remain in the cycle and divide, or to withdraw from the cycle and adopt a different cell fate. During this time, environmental signals, which regulate the synthesis of the G1 cyclins, are coupled to cell division. In this context, mammalian D-type cyclins have been shown to control progression through the G1 phase of the mammalian cell cycle. Specifically, cyclin D1 has been reported frequently to be amplified, over-tran-scribed and overexpressed in human breast carcinomas. Although the effects of cyclin D1 overexpression have been examined in human breast carcinoma cell lines, the biological consequences of cyclin D1 expression in normal human mammary epithelial cells remain to be elucidated. In this study we have stably over expressed cyclin D1 in human mammary luminal epithelial cells in order to more directly address the role of cyclin D1 in cell cycle control and tumorigenesis of the human breast. Here, we demonstrate that the effect of cyclin D1 overexpression in these cells is to reduce their growth factor dependency, as well as shorten the duration of G1 and correspondingly reduce the mean generation time. Collectively, our data indicate that deregula-tion of cyclin D1 expression in human mammary epithelial cells can provide a growth advantage and hence contribute to the oncogenic potential of these cells. © Rapid Science Ltd.  相似文献   

20.
 目的 研究1α,25(OH) 2D3对胃癌细胞增殖和细胞周期的影响,并探讨其相关的作用机制。方法 BGC-823和SGC-7901胃癌细胞株分别给予终浓度为10-10~10-7mol/L的1α,25(OH) 2D3处理72h,用MTT法检测细胞抑制率;用流式细胞仪检测细胞周期;用RT-qPCR技术检测细胞周期相关基因P21、cyclinD1、cyclinE1和CDK6 mRNA表达。 结果1α,25(OH) 2D3对胃癌细胞的增殖抑制率具有浓度依赖性, 1α,25(OH) 2D3干预导致BGC-823和SGC-7901细胞株G1期细胞比例升高,S期细胞比例降低 (P<0.05); 1α,25(OH) 2D3干预后,BGC-823和SGC-7901胃癌细胞P21 mRNA表达升高(P<0.01),而cyclinD1、cyclinE1和CDK6 mRNA表达降低(P<0.01)。结论 1α,25(OH) 2D3抑制胃癌细胞增殖,诱导细胞周期阻滞,可能与上调P21,下调cyclinD1、cyclinE1和CDK6的表达有关。  相似文献   

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