LCL161联合Z-VAD-FMK对人乳腺癌细胞MCF-7和MDA-MB-231增殖的影响

目的:探讨第二个线粒体衍生的半胱氨酸蛋白酶激动剂小分子(Smac)类似物LCL161联合天冬氨酸蛋白水解酶(caspase)抑制剂Z-VAD-FMK诱导细胞发生坏死性凋亡对人乳腺癌细胞MCF-7和MDA-MB-231增殖的影响。方法:体外培养MCF-7、MDA-MB-231细胞株。噻唑蓝(MTT)法检测2种细胞株空白对...     

Bone metastasis is strongly associated with estrogen receptor-positive/progesterone receptor-negative breast carcinomas

Bone is one of the most common sites of distant metastasis for breast carcinomas. In this study, our objective is to identify molecular markers and molecular subtypes that may predict patients at higher risk of developing bone metastasis. Immunohistochemical analysis with antibodies against estrogen receptor α, progesterone receptor, androgen receptor, Her2/neu, epidermal growth factor receptor, CK5/6, CK14, CK17, CK8, and CK18 was performed on representative sections of 21 breast carcinomas with bone metastasis and 94 cases without bone metastasis. The expression rates of receptors, subtype distributions (basal versus nonbasal) of 3 molecular classifications (cytokeratin, triple negative, and cytokeratin/triple negative), and 5 subtypes of cytokeratin/triple negative classification were compared between these 2 groups. We found that (1) the breast cancers with bone metastasis were associated with a significant percentage of estrogen receptor–positive/progesterone receptor–negative tumors compared with tumors without bone metastasis (38% versus 6%, P < .0001). (2) There was significant difference on estrogen receptor expression between high grade and non–high grade in tumors with or without bone metastasis (P = .0084 and 1.0000, respectively). (3) The breast cancers with bone metastasis were more likely to be estrogen receptor positive (85%) and androgen receptor positive (95%) compared with those without bone metastasis (59% and 74%, respectively, both P < .05). (4) There was no significant difference between tumors with or without bone metastasis in subtype distribution (basal versus nonbasal) among all 3 molecular classifications. (5) Luminal B carcinomas of cytokeratin/triple negative classification tended to be associated with bone metastasis but not to a statistically significant extent. In conclusion, bone metastasis is strongly associated with estrogen receptor–positive/progesterone receptor–negative tumors. Significant difference in estrogen receptor expression between high-grade and non–high-grade tumors with bone metastasis suggests that different panels of molecular markers should be used to predict bone metastasis in these 2 groups of tumors.     

Comparison of possible carcinogenic estradiol metabolites: effects on proliferation, apoptosis and metastasis of human breast cancer cells

OBJECTIVES: Certain estradiol metabolites may play a pivotal role in breast carcinogenesis. Of special interest are the metabolites 2-hydroxyestradiol (2-OHE2), which can react anti-carcinogenically, and 4-hydroxyestradiol (4-OHE1) and 16a-hydroxyestrone (16-OHE1), which may have procarcinogenic potential. In the present study, we have compared for the first time the effect of these metabolites and their parent substance 17beta-estradiol (E2) on proliferation, apoptosis, apoptosis markers and markers of metastatic property of human breast cancer cells. METHODS: MCF-7 cells (human estrogen-receptor positive metastatic breast cancer cell line) were incubated with the estrogens at concentrations of 0.1-100 nM. Cell proliferation rate was measured by the ATP-assay. Apoptosis was measured by cell death assay and the apoptosis markers cytochrome C, Bcl-2, Fasl and p53 were determined in cell lysates by ELISAs. The markers of metastatic property of the cell line, VEGF and MCP-1 were measured in the cell supernatant by ELISAs. RESULTS: The estrogens E2, 4-OHE2 and 16-OHE1 display a proliferative effect on MCF-7 cells which is accompanied by a down-regulation of apoptosis. Various markers of apoptosis such as Bcl-2, cytochrome C and p53 appear to be involved. No significant effect was found for the metabolite 2-OHE2. VEGF and MCP-1 were up-regulated by E2 and 16-OHE1, whereas 2-OHE2 and 4-OHE2 did not show any effect. CONCLUSIONS: The most potent estrogen regarding proliferation, apoptosis and metastasis of breast cancer cells seems to be estradiol. However, the estradiol metabolites 4-OHE2 and 16-OHE1 elicit similar properties on cell proliferation, apoptosis and metastasis as compared to estradiol but only at higher concentrations. In contrast 2-OHE2 did not show any significant effect on these parameters. Thus, intracellular estradiol metabolism may determine an individual's risk for breast carcinogenesis.     

二甲双胍联合紫杉醇对人乳腺癌细胞凋亡及AMPK信号通路的影响

目的:探索二甲双胍联合紫杉醇对乳腺癌MCF-7细胞活力和凋亡的影响及其可能的机制。方法:采用不同浓度(2、5、10、20、40和80 mmol/L)二甲双胍作用于体外培养的MCF-7细胞,MTT法检测细胞的活力。采用2 mmol/L二甲双胍和2. 4 mg/L紫杉醇单独或联合处理细胞,并加入一磷酸腺苷活化的蛋白激酶(AMPK)信号转导通路抑制剂compound C。实验分为对照组、二甲双胍组、紫杉醇组、联合组和联合+compound C组;流式细胞术检测细胞的凋亡率,采用RT-qPCR和Western blot法检测Bax、Bcl-2和caspase-3的mRNA和蛋白表达量,Western blot检测AMPK和P21蛋白的表达量。结果:不同浓度二甲双胍(2、5、10、20、40和80 mmol/L)显著抑制乳腺癌细胞的活力(P 0. 05),且具有一定浓度依赖性。与对照组相比,2 mmol/L二甲双胍和2. 4 mg/L紫杉醇单独或联合均可显著抑制细胞活力并诱导其凋亡(P 0. 05),显著下调Bcl-2水平(P 0. 05),上调Bax和caspase-3水平(P 0. 05),促进AMPK和P21蛋白表达。联合使用的效果优于单独使用。加入AMPK抑制剂可削弱此作用。结论:二甲双胍联合紫杉醇可抑制乳腺癌MCF-7细胞活力,诱导其凋亡。此作用与激活AMPK信号转导通路并调节细胞凋亡信号通路有关。     

VEGF基因特异性siRNA转染后对人乳腺癌细胞增殖和凋亡的影响

目的：探讨利用干扰RNA（RNAi）抑制血管内皮生长因子（VEGF）基因表达对乳腺癌细胞MCF-7增殖和凋亡的影响。方法：设计针对VEGF基因的小干扰RNA（siRNA）,合成DNA模板,体外转录siRNA。以脂质体转染法将双链siRNA导入MCF-7细胞后,用MTT比色法检测siRNA对MCF-7细胞增殖的影响。通过Hoechst33258染色观察MCF-7细胞的凋亡。用流式细胞术检测细胞周期的改变,RT-PCR检测VEGF mRNA表达的变化,免疫细胞化学法检测VEGF蛋白的表达。结果：所设计的两个靶位点siRNA,均能有效地抑制MCF-7细胞的增殖,诱导细胞凋亡,使细胞周期阻滞于G0/G1期,VEGFmRNA及其蛋白的表达明显减少;而作为阴性对照的错义序列组siRNASCR则没有上述效应。结论：体外转录合成的siRNA可抑制MCF-7细胞中VEGF基因的表达,抑制细胞增殖,促进细胞凋亡。     

蒿甲醚对人乳腺癌细胞的增殖抑制作用研究

目的研究蒿甲醚对人乳腺癌MDA-MB-231细胞增殖活性、凋亡的影响及其机制。方法利用浓度为0,2.5,5,10,20,40,80及160μmol/L的蒿甲醚孵育24h。利用CCK8法测定细胞增殖抑制率。然后用浓度为0、20、40及80μmol/L的蒿甲醚培养MDA-MB-231细胞24h,利用Annexin V-FITC/PI法检测细胞凋亡及细胞周期。最后利用Western blot法检测MDA-MB-231细胞活化caspase-3及8的表达水平。结果蒿甲醚使MDA-MB-231细胞的增殖活性受到显著抑制,同时随着浓度升高抑制作用增强。与对照组相比,蒿甲醚显著促进MDAMB-231细胞的凋亡并使细胞周期维持在G+M期,显著上调caspase-3及8的活化水平。结论蒿甲醚对人乳腺癌2MDA-MB-231细胞有潜在的治疗作用。     

HSP90在乳腺癌细胞增殖中的作用与机制研究

目的： 应用热休克蛋白90(HSP90)功能特异性抑制剂格尔德霉素(GA)研究HSP90在乳腺癌细胞增殖中的作用，进而探讨相关机制。方法: 培养人乳腺癌细胞株MDA-MB-435s，采用MTT法检测GA对MDA-MB-435s细胞的生长抑制作用，流式细胞术分析细胞周期，应用Western免疫印迹法检测细胞内Stat3磷酸化状态和突变型p53表达变化。结果: 不同浓度GA对乳腺癌MDA-MB-435s细胞有生长抑制作用，呈时效量效依赖关系，GA作用后细胞呈现G2/M期阻滞。400 nmol/L GA作用48h后，细胞内Stat3磷酸化水平明显低于对照组，同时突变型p53表达明显低于对照组。结论: 抑制HSP90功能可明显抑制乳腺癌MDA-MB-435s细胞的增殖，此与下调细胞内Stat3磷酸化水平和突变型p53表达有关。     

Subgroups of non-atypical hyperplasia of breast defined by proliferation of oestrogen receptor-positive cells

In normal breast, there is a negative association between expression of oestrogen receptor (ER) and the proliferation marker Ki67, indicating that ER-positive (ER+) cells do not divide, or that the receptor is down-regulated when they do so. However, dual staining has been found in carcinomas and precancerous lesions, indicating that abnormal regulation of ER could be important in breast tumourigenesis. ER expression in relationship to cell proliferation was studied in 241 foci of hyperplasia of usual type (HUT), a lesion associated with a 1.5 to 2-fold increase in risk of developing breast cancer. Dual label immunofluorescence was employed, using the antibodies 1D5 and Ki67. Two hundred and thirteen foci of HUT contained ER+ cells, which were distributed singly or contiguously and increased with age. Most foci resembled normal breast, but 51 contained dual labelled cells, which did not increase with age. Some of these foci exhibited few, scattered ER+ cells with greater proliferation rates than the ER-negative (ER-) cells, whereas others contained many, contiguous ER+ cells, whose rate of proliferation was less than that of the ER- cells. The latter picture is similar to that which has previously been reported in atypical ductal hyperplasia and ductal carcinoma in situ. The first type of HUT may evolve into the second. The proportion of Ki67+ cells that was ER+ was similar in both types, suggesting a homeostatic mechanism that slows the proliferation of ER+ cells as they become confluent. Overriding this inhibition may be crucial in further progression. Non-atypical hyperplasia is thus heterogeneous in ER expression and proliferation and a significant proportion exhibit abnormal regulation of ER. These findings could have implications for pathological diagnosis, risk assessment, and prophylactic hormonal therapy.     

雌二醇对大鼠海马神经干细胞增殖的影响

目的观察雌二醇对大鼠海马神经干细胞增殖的影响及其作用机制。方法取20只孕17d的SD大鼠海马组织,进行神经干细胞的培养和增殖,添加不同浓度的雌二醇(E2)。通过5-溴脱氧尿嘧啶核苷(BrdU)免疫荧光、MTT方法检测神经干细胞的增殖;通过免疫荧光技术和巢蛋白(Nestin)双标观察神经干细胞球中雌激素受体ERα和ERβ的表达情况。结果 BrdU与MTT检测结果显示,随着雌二醇浓度从10-10mol/L增加至10-8mol/L,神经干细胞数量逐渐增加。雌二醇在10-8mol/L时,细胞增殖数目最多而且细胞活力最好。随着雌二醇浓度进一步增加至10-6mol/L,神经干细胞增殖能力逐渐下降。免疫荧光技术检测显示神经干细胞均表达ERα和ERβ两种受体。结论在一定浓度范围内,雌二醇能促进海马神经干细胞的增殖,并可能是通过ERα和ERβ介导促进神经干细胞增殖。     

低频超声联合紫杉醇对人乳腺癌MCF-7细胞增殖和凋亡的影响

目的研究低频超声和紫杉醇联合应用对乳腺癌MCF-7细胞增殖和凋亡的影响以及其可能机制。方法培养乳腺癌MCF-7细胞,随机分为4组:对照组、低频超声组、紫杉醇组和低频超声+紫杉醇组。低2频超声组为超声840k Hz,0.75W/cm×3min辐照;紫杉醇组为药物浓度为10nmol/L培养24h;联合组叠加处理因素。应用CCK-8检测细胞增殖,应用流式细胞仪和凋亡试剂盒检测各组细胞凋亡,应用流式细胞仪和ROS试剂盒检测各组细胞ROS水平,应用Western Blot实验检测凋亡相关蛋白表达。结果单独应用低频超声或紫杉醇均能抑制MCF-7细胞增殖,诱导细胞凋亡,升高细胞内活性氧水平,增加凋亡相关蛋白(cleaved caspase-3、cleaved caspase-2、Bax)的表达水平,降低Bcl-2的表达水平。与单独应用组相比,低频超声和紫杉醇联合,显著增强了上述作用。结论低频超声和紫杉醇联合作用,极大增强了抑制MCF-7细胞增殖,诱发其凋亡的作用,其作用可能和线粒体凋亡途径相关。     

人乳腺癌细胞系中上皮型钙黏连蛋白表达对其黏附和增殖的影响

目的 探讨上皮型钙黏连蛋白(E-cadherin,E-cad)表达对MDA-MB-231人乳腺癌细胞黏附力及增殖的影响.方法 采用脂质体转染方法将携带有E-cad基因的重组真核表达质粒E-cadpcDNA3转染入E-cad阴性MDA-MB-231人乳腺癌细胞系,通过G418筛选,Western blot法鉴定出E-cad过表达的阳性单克隆细胞株.分别通过三种不同的黏附试验检测E-cad转染前后细胞自身黏附、与基质黏附及与其他细胞黏附能力的变化:免疫沉淀法检测表达的外源性E-cad能否与内源性连环蛋白(β-catenin,β-cat)发生相互作用.Western blot检测E-cad表达后细胞内β-cat、细胞周期蛋白(cyclin)D1蛋白的表达变化;MTT法检测细胞的生长和增殖能力状况;流式细胞仪检测转染E-cad前后细胞凋亡变化情况.免疫细胞化学直接二步法检测β-cat定位变化.结果 通过稳定转染,获得了稳定表达E-cad的两个细胞株Ecad-231-7和Ecad-231-9.MDA-MB-231细胞在不贴壁培养时大部分呈单细胞状态,而两个表达E-cad的细胞株都形成大细胞团;MDA-MB-231、Ecad-231-7和Ecad231-9与HCT116细胞共孵育30 min后的平均黏附率分别为39.0%、60.0%和59.5%.MDA-MB-231细胞在EDTA作用5 min后的平均脱落率为37.4%,Ecad-231-7和Ecad-231-9细胞分别下降为4.2%和7.2%,即E-cad表达后乳腺癌细胞的自身黏附力、与基质的黏附力及与其他细胞的黏附力均增强;且细胞内过表达的外源性的E-cad与β-cat结合,使细胞内cyclin D1表达下降,细胞增殖受到抑制.常规培养48 h后MDA-MB-231、Ecad-231-7和Ecad-231-9细胞的凋亡率分别为1.9%、2.0%和2.1%,E-cad表达对细胞的凋亡没有明显影响.二步法染色显示胞质内β-cat增加.结论 成功建立了稳定表达E-cad蛋白的单克隆细胞株Ecad-231-7和Ecad-231-9.表达的E-cad通过β-cat-cyclinD1途径增强癌细胞黏附力、抑制癌细胞增殖.

Abstract：

Objective To investigate the role that E-cadherin (E-cad) plays on cell adhesion and proliferation of human breast carcinoma. Methods E-cad expression vector was transfected into an E-cadnegative human breast carcinoma MDA-MB-231 cells. G418 was used to screen positive clones. E-cad,β-catenin (β-cat) and cyclin DI expressions of these clones were confirmed by Western blot. Their cell-cell and cell-matrix adhesion abilities were detected. E-cad/β-catenin interaction was confirmed by immunoprecipitation. Cell proliferation was evaluated by MTT. Cell apoptosis was analyzed by flow cytometry. Direct two-step immunocytochemistry was used to detect the localization of β-cat. Result E-cad ( + ) cell strains Ecad-231-7 and Ecad-231-9 were established. When cultured in ultra-low-binding dishes Ecad-231 cells grow in suspension while Ecad-231-7 and Ecad-231-9 cells grow in large clamps. When MDA-MB-231, Ecad-231-7 and Ecad-231-9 respectively. The average detachment rates by EDTA for 5 min are 37.4%, 4. 2% and 7.4% respectively. So E-cad expression enhanced hemotypic and heterotypic cell-cell adhesion and cell-matrix adhesion. Forced exogenously expressed E-cad could combine with endogenous β-cat, whereas down stream cyclin D1 expression was significantly decreased, as evidenced by Western blot. The rates of cell apoptosis of MDA-MB-231, Ecad-231-7 and Ecad-231-9 were 1.8%, 2. 0% and 2.1%. Expression of E-cad had no obvious effect on the apoptosis of tumor cells with regular culture.β-cat increased in the cytoplasma. Conclusions Two monoclonal tumor cell strains ( Ecad-231-7 and Ecad-231-9) stably expressing E-cad were successfully established. E-cad could enhance adhesion and inhibit proliferation of human breast carcinoma cells through a pathway involving β-cat and cyclin D1.     

Breast cancer risk during HRT: influence of estradiol metabolites on breast cancer and endothelial cell proliferation

OBJECTIVES: Long-term hormone replacement therapy is associated with an increased breast cancer risk. Evidence is accumulating that estradiol metabolites are involved in carcinogenesis. These metabolites may have proliferating and anti-proliferative properties. We have investigated the effect of 14 metabolites on the proliferation of human breast cancer cells and on the proliferation of human vascular endothelial cells. METHODS: As cell model, human umbilical vein endothelial cells (HUVEC) and the human breast cancer cell line MCF-7 were used. The relationship between dosage and effect was tested over the pharmacological concentration range of 10(-8) to 10(-5) M. RESULTS: In HUVECs, all of 10 A-ring metabolites tested stimulated the growth of the endothelial cells at the lower concentrations. At the highest concentration, some A-ring metabolites caused significant inhibitions. The D-ring metabolites showed no marked effects compared to the A-ring metabolites. In MCF-7 cells also, nearly all A-ring metabolites demonstrated a biphasic reaction behaviour on cell proliferation. For the D-ring metabolites, this biphasic pattern was only found for 16 alpha-hydroxyestrone, but the inhibitory effect of this metabolite was weak. CONCLUSION: These results indicate that certain endogenous estradiol metabolites are able to stimulate breast cancer cell proliferation, and others may be suitable for breast cancer treatment when used in high dosages, since they inhibit cancer cell growth as well as neoangiogensis. This may be of special importance for therapy, since some of these metabolites are virtually devoid of any oestrogenic activity.     

雌激素对培养的兔平滑肌细胞增殖与移行的影响

目的: 探讨雌激素对培养的兔平滑肌细胞增殖与移行的影响。方法: 分别测定不同浓度雌激素作用下兔血管平滑肌细胞[³H]-TdR掺入量、增殖细胞核抗原(PCNA)的表达、血管平滑肌细胞(VSMC)移行的变化。结果: 低浓度(1 nmol/L)的雌激素组的培养细胞[³H]-TdR掺入量及VSMC平均光密度值、VSMC移行细胞数与对照组相比无明显差异(P>0.05), 较高浓度(10 nmol/L、100 nmol/L)的雌激素可以显著降低培养的[³H]TdR掺入量及培养VSMC平均光密度值, 并能显著减少VSMC移行细胞数目(P<0.01)。结论: 雌激素可抑制血管平滑肌细胞的增殖与移行, 从而发挥抗动脉粥样硬化作用。     

VDUP1对乳腺癌细胞MCF-7增殖及迁移的影响

目的:探讨过表达/沉默维生素D3上调蛋白1(vitamin D3 up-regulated protein 1,VDUP1)基因对人乳腺癌细胞系MCF-7增殖和迁移能力的影响及相关作用机制。方法:通过基因过表达/干扰技术上调/下调乳腺癌细胞系MCF-7中VDUP1基因的表达;实时荧光定量PCR检测细胞中VDUP1的mRNA表达水平;CCK-8法、Brd U实验和Transwell细胞迁移实验分别用于检测细胞增殖和迁移能力;Western blot检测细胞中Akt、p-Akt、GSK3β和p-GSK3β的蛋白水平。结果:基因过表达/干扰技术可上调/下调乳腺癌细胞系MCF-7中VDUP1基因的表达;过表达VDUP1基因后,MCF-7的细胞活力、DNA合成和细胞迁移能力显著降低(P0.05),而沉默VDUP1基因后,MCF-7的细胞活力、DNA合成和细胞迁移能力则显著升高(P0.05)。此外,过表达VDUP1基因可下调p-Akt和p-GSK3β的蛋白水平(P0.05),而沉默VDUP1基因的结果则相反。结论:改变VDUP1基因表达水平可影响MCF-7细胞的增殖和迁移能力,其作用机制可能与Akt/GSK3β信号通路有关。     

CSN6对人乳腺癌细胞增殖的影响

目的观察COP9信号复合体(COP9 signalosome,CSN)6号亚单位(CSN6)对乳腺癌细胞(MCF-7)增殖的影响。方法应用Western blot检测CSN6和PTEN蛋白表达,MTT法及划痕损伤实验检测转染CSN6及磷酸酶基因(PTEN)质粒的细胞增殖生长的情况。结果 MCF-7细胞转染shRNA-CSN6,在CSN6蛋白表达降低的同时,PTEN的表达增高。乳腺癌细胞MDA-MB-468细胞在转染PTEN后,其增殖受到抑制,而转染CSN6后,能够逆转PTEN的抑制作用,促进细胞生长。结论 CSN6有可能通过降解PTEN而引起乳腺癌细胞的增殖生长。     

槲皮素对人卵巢癌SKOV-3细胞增殖的影响

 目的：探讨槲皮素对人卵巢癌SKOV-3细胞增殖抑制和凋亡的影响,为卵巢癌临床治疗提供依据。方法：不同浓度槲皮素处理卵巢癌SKOV-3细胞后,采用MTT实验检测细胞增殖抑制作用并计算抑制率,细胞免疫化学染色法鉴定细胞凋亡,流式细胞术检测细胞周期及细胞凋亡。结果：槲皮素能够抑制SKOV-3细胞的增殖,且呈时间和剂量依赖性,免疫荧光显示槲皮素对SKOV-3细胞具有诱导凋亡作用,流式细胞术显示SKOV-3细胞被阻滞在S期, G2/M期细胞比例降低,凋亡率上升。结论：槲皮素在体外能够抑制卵巢癌SKOV-3细胞的增殖,阻止细胞由S期向G2期移行,促进其凋亡。     

Surface immunoglobulin phenotype of complement receptor-positive and complement receptor-negative B cells of normal and xid immunodeficient mice

Single- and dual-parameter fluorescence-activated cell sorter analyses of complement receptor-positive and -negative (CR⁺ and CR^?) splenic B cells of normal and xid immunodeficient mice were performed to determine the frequencies of surface (s) IgM⁺ and sIgD⁺ cells, as well as the quantities of sIgM and sIgD on these cells. Single parameter analysis revealed identical frequencies of sIgM⁺ and sIgD⁺ cells in the CR⁺ B cell population of normal mice. In contrast, the percentage of sIgM⁺ cells exceeded that of sIgD⁺ cells in the CR^? normal and CR⁺ xid B cell population to a similar extent. CR^? xid B cells showed an even greater discrepancy between sIgM⁺ and sIgD⁺ cells. Dual-parameter analysis of CR⁺ normal B cells showed the typical sIg phenotype of mature B cells, i.e. an intermediate density of sIgM and a high density of sIgD. The CR⁺ xid B cell population displayed an increase in cells with high sIgM and no-to-low sIgD and a decrease in cells with intermediate sIgM and high sIgD when compared to CR⁺ normal cells. CR^? B cells from normal and xid immunodeficient mice were similar in that both consisted largely of a cell population with low sIgM and no-to-low sIgD. However, the CR^? normal B cell population also contained cells with intermediate sIgM and high sIgD, which were lacking in the CR^? xid cell population. Similar results were obtained when CR⁺ and CR^? B cells from normal and xid mice were purified from a small resting B cell population, isolated by elutriation. This indicates that the sIg phenotype of CR^? cells is not due to the presence of large cells which have lost sIgD during activation.     

IGFBP7对人乳腺癌MCF-7细胞增殖的影响及其机制

目的: 探究胰岛素样生长因子结合蛋白7(IGFBP7)对人乳腺癌MCF-7细胞增殖的影响及其分子生物学机制。方法: 将质粒pCMV6-IGFBP7转染MCF-7细胞,构建稳定表达IGFBP7的MCF-7细胞系;采用Western blotting检测IGFBP7在MCF-7细胞稳定转染子的表达;采用软琼脂培养克隆形成实验检测IGFBP7对MCF-7细胞克隆形成能力的影响;采用流式细胞术检测IGFBP7对MCF-7细胞周期的影响;采用Western blotting检测IGFBP7对MCF-7细胞细胞外信号调节激酶1/2(ERK1/2)、p-ERK1/2、细胞周期素D1(cyclin D1)、细胞周期素依赖性激酶4(CDK4)、cyclin E、CDK2、p21^CIP1/WAF1、p27^KIP1、p53、视网膜母细胞瘤蛋白(Rb)和p-Rb蛋白含量的影响。结果: (1)只有稳定转染质粒pCMV6-IGFBP7的MCF-7细胞表达IGFBP7。(2)IGFBP7能够显著降低MCF-7细胞的克隆形成率(P<0.01),阻止细胞从G₁期进入S 期,使其停滞于G₁期(P<0.01)。(3)IGFBP7能够显著抑制ERK1/2的磷酸化(P<0.01)。(4)IGFBP7能够下调cyclin D1和cyclin E蛋白表达(P<0.01),上调p27^KIP1、p21^CIP1/WAF1和p53蛋白表达(P<0.01),抑制Rb的磷酸化(P<0.01)。(5)MEK1/2阻断剂PD98059可部分模拟IGFBP7的肿瘤抑制效应。结论: (1) IGFBP7可通过下调cyclin D1和cyclin E蛋白表达,上调p27^KIP1、p21^CIP1/WAF1和p53蛋白表达,以及抑制Rb磷酸化发挥抗肿瘤作用;(2) IGFBP7对cyclin D1和p27^KIP1的调节可能与其抑制ERK1/2信号通路有关。