Anticancer property of sediment actinomycetes against MCF-7 and MDA-MB-231 cell lines

ObjectiveTo investigate the anticancer property of marine sediment actinomycetes against two different breast cancer cell lines.MethodsIn vitro anticancer activity was carried out against breast (MCF-7 and MDA-MB-231) cancer cell lines. Partial sequences of the 16s rRNA gene, phylogenetic tree construction, multiple sequence analysis and secondary structure analysis were also carried out with the actinomycetes isolates.ResultsOf the selected five actinomycete isolates, ACT01 and ACT02 showed the IC50 value with (10.13±0.92) and (22.34±5.82) μg/mL concentrations, respectively for MCF-7 cell line at 48 h, but ACT01 showed the minimum (18.54±2.49 μg/mL) level of IC50 value with MDA-MB-231 cell line. Further, the 16s rRNA partial sequences of ACT01, ACT02, ACT03, ACT04 and ACT05 isolates were also deposited in NCBI data bank with the accession numbers of GQ478246, GQ478247, GQ478248, GQ478249 and GQ478250, respectively. The phylogenetic tree analysis showed that, the isolates of ACT02 and ACT03 were represented in group I and III, respectively, but ACT01 and ACT02 were represented in group II. The multiple sequence alignment of the actinomycete isolates showed that, the maximum identical conserved regions were identified with the nucleotide regions of 125 to 221st base pairs, 65 to 119th base pairs and 55, 48 and 31st base pairs. Secondary structure prediction of the 16s rRNA showed that, the maximum free energy was consumed with ACT03 isolate (-45.4 kkal/mol) and the minimum free energy was consumed with ACT04 isolate (?7.6 kkal/mol).ConclusionsThe actinomycete isolates of ACT01 and ACT02 (GQ478246 and GQ478247) which are isolated from sediment sample can be further used as anticancer agents against breast cancer cell lines.

REVERSION OF MULTIDRUG RESISTANCE IN THE P-GLYCOPROTEIN POSITIVE BREAST CANCER CELL LINE(MCF-7/ADR) BY INTRODUCTION OF HAMMERHEAD RIBOZYME

A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line(MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.

Studies on mechanism of cis9,trans11-CLA and trans10,cis12-CLA inducing apoptosis of human breast cancer cell line MCF-7

Objective： The aim of the study was to explore the activities of cis9, trans11-CLA （C9, t11-CLA） and transl0, cis12-CLA （t10, c12-CLA） inhibiting tumor, and investigate their relationships with PPARy and apoptotic proteins, and mechanism of anti-cancer. Methods： The inhibitory rate, cell growth curve and apoptotic morphological observation of MCF-7 cells were obtained by MTT assay, trypan blue staining and Hoechst33342 fluorescence staining. The apoptotic rate and cell cycle were detected with flow cytometry. Transcriptional level of genes was detected with RT-PCR semi-quantitative method, and Western blot was performed to detect proteins levels. Results： The two CLA isomers could reduce cell proliferation （P 〈 0.05）, increase apoptotic rate （P 〈 0.05）, and increase obviously the transcriptional and protein levels of PPARy （P 〈 0.01）. The synchronism and correlation between the effects of CLA to PPARy and apoptotic proteins Bax, Bcl-2, Caspase 3 changes were found with the dose- and time-dependent manners. There was cooperative relation between the levels of PPARy and the rates of Bax/Bcl-2, Caspase 3 （small fragment） by experiments of PPARy inhibitor GW9662 and ligand Rosiglitazone. Conclusion： The apoptotic pathway of PPARy-Bcl-2-Caspase 3 signaling was found. The C9, t11-CLA and tl0, c12-CLA could inhibit MCF-7 cell proliferation and promote apoptosis via activating PPARy-Bcl-2-Caspase 3 pathway. CLA may be a kind of activator of PPARv.

Anticancer activity of Tephrosia purpurea and Ficus religiosa using MCF 7 cell lines

Objective:To investigate anticancer activity of different fractions of Tephrosia purpurea[TP] （Sharapunkha,Fabaceae） and Ficus religiosa[FR]（Peepal,Moraceae）.Methods:The fractions of TP and FR were prepared and tested for in vitro anticancer activity using human MCF 7 cell line by trypan blue exclusion method.Results:The result showed that among all these fractions of TPI.TPIII.FRI and FRIII showed better anticancer activity compared to other fractions.The IC50 value for TPI（152.4μM）,TPIII（158.71μM）.FRI（160.3μM） and for FRIII（222.7μM） was observed.Conclusions:The present study shows anticancer potential of TP and FR fractions in MCF 7 cell line.

The activity of <i>Rhaphidophora pinnta</i>Lf. Schott leaf on MCF-7 cell line

Ekor naga’s leaf (Rhaphidophora pinnata (Lf) Schott) is a type of vines and climbing plant. The leaves are elongated round and hollowed inside. This plant had been using for the treatment of breast cancer. Extraction with percolation method has been done in ekor naga’s leaves with ethanol, and fractionated by nhexane, chloroform and ethyl acetate using liquid-liquid extraction (LLE). Cytotoxicity assay of ethanol extract, n-hexane fraction, chloroform fraction, ethyl acetate fraction and water fraction against MCF-7 cells were done using MTT method (3-(4,5-dimetiltiazol-2-il)-2,5-diphenyl tetrazolium bromide). Phytochemical screening results showed the presence of the compounds such as triterpenoida/steroid, alkaloid, flavonoid, tannin, and saponin. n-hexane fraction was positive for the presence of triterpenoida/steroid, chloroform fraction containing alkaloids, saponin and triterpenoid;ethyl acetate fraction contained, flavonoid, tannin, and the fraction of water indicated the presence of tannin and saponin. Secondary metabolite compounds in ethanol extract, chloroform fraction and ethyl acetate fraction gave positive results against MCF-7 cells. Cytotoxicity assay of MCF-7 cell line showed that crude ethanol extracts had 112.240 mcg/ml IC50 chloroform fraction IC50 was 59.082 mcg/ml, and ethyl acetate fraction IC50 was 812.663 mcg/ml.

Cytotoxic Activity of <i>Thelesperma megapotamicum</i>Organic Fractions against MCF-7 Human Breast Cancer Cell Line

Thelesperma megapotamicum (Asteraceae) is commonly used in Argentine to treat various diseases (renal, digestive affections, and as anaesthesia). The present study showed the mechanisms involved “in vitro” cytotoxicity of T. megapotamicum Fractions. Five Fractions (F1 - F5) were separated by column chromatography (Silica gel) using hexane:diethyl ether as eluents. Viability was evaluated in Human breast carcinoma cell line (MCF-7) by staining with crystal violet. With respect to F1 Fraction treatment, the cell survival was 49.14% ± 8.87%, while the F2 and F3 ones exhibited a strong reduction of cell viability to only 26.35% ± 1.63% and 23.3%1 ± 0.53% of the control cell at 50 μg/ml, respectively. Apoptotic effect of these Fractions was detected using FITC-labeled Annexin V and propidium iodide binding assays and was confirmed by a higher proportion of apoptotic cells due to F2 and F3 treatments. T. megapotamicum active Fractions could facilitate the tumoral cells death by decreasing the activity of the enzyme Gamma-glutamyltranspeptidase and causing alteration in cell membrane sialoglycoconjugates and others involved anticancer mechanisms including apoptosis.

Synthesis, Characterization of Ruthenium Compounds and Studies of Biological Effects in MCF-7 Tumors Cell Lines

This work presents the synthesis and characterization of compounds derived from the ruthenium transition metal with the nitrogenous ligand 4-aminopy- ridine (4-ampy). The synthesized compounds were characterized by FTIRmed spectroscopy and TG-DTA thermal analysis. For the cytotoxic evaluation of ruthenium compounds, a 66.0 μM aqueous solution containing the complex and the study of data observed in the biological assessment was performed using variance (ANOVA) analysis, followed by Tukey’s multiple comparisons test. Differences between treatments were considered significant when the p-value was less than 0.05 (p < 0.05). TG/DSC thermal analysis for the first complex suggests a stoichiometry of [Ru(Cl)3(4-ampy)(H2O)2]·1/2H2O, which, due to the low solubility in an aqueous medium, was modified to increase its solubility for biological tests. The analysis of the spectra in the medium infrared region (FTIR) for the complex [Ru(Cl)3(4-ampy)(H2O)2]·1/2H2O, shows displacements of the bands observed at 1625 - 1566 cm﹣1 ν(C=C) e (C=N), indicating that coordination to the metallic center occurred by this group. Band displacements were observed in the modified Ru (III) complex, which suggests the presence of the 4-ampy ligand and the coordination by the groups ν(C=C) and (C=N) after the modification. In recent years, researchers worldwide have concentrated on obtaining, developing, and modifying drugs used as chemotherapeutic agents. The evaluation of the cell viability of the modified Ru (III) compound demonstrated cytotoxic effects in the MCF-7 cell line (15.33% ± DP 2.7) but did not affect normal cells (PBMC), which reflects the potential for possible applications.

Construction of Cox7a2 fluorescent vector and its effect on cytochrome C oxidase activity in mouse Sertoli cell line TM4

Objective To construct Cox7a2 fluorescent vector and study its effect on cytochrome C oxidase ( COX) activity in mouse Sertoli cell line TM4. Methods The coding region of CoxTa2 was amplified from mouse Sertoli cell line TM4 by RT-PCR. PCR product was

Effects of 4-(3-Chloro-Benzyl)-6,7-Dimethoxy-Quinazoline on Kinetics of P120-Catenin and Periplakin in Human Buccal Mucosa Squamous Carcinoma Cell Line

In order to detect molecular markers for the epidermal growth factor inhibitor 4-(3-chloro-benzyl)- 6,7-dimethoxy-quinazoline (tyrphostin), we investigated the kinetics of p120-catenin and periplakin in the human buccal mucosa squamous cancer cell line BICR 10 treated with 3 nM tyrphostin. Growth of BICR 10 cells was inhibited by treatment with tyrphostin. Although changes were not observed in the expression of EGFR and p120-catenin, expression of Akt, Src and periplakin in BICR 10 treated with 3 nM tyrphostin tended to decrease. In addition, phosphorylation of EGFR, Akt and Src was inhibited by treatment with tyrphostin. On immunocytochemical staining, immunoreactions with phosphorylated EGFR, phosphorylated Akt and phosphorylated p120-catenin were weak in BICR 10 treated with tyrphostin. There was a slight immunocy to chemical reaction to periplakin in BICR 10 cells induced by tyrphostin. In conclusion, the decrease in phosphorylation in EGFR and p120-catenin by tyrphostin, following the decrease in Src or Akt phosphorylation, may inhibit expression of several growth factors associated with the proliferation and migration of cancer cells.

THE EFFECTS OF ESTRADIOL ON BREAST CANCER CELL LINES

The estradiol effects on breast cancer cell lines including estrogen receptors (ER) positive and negative were studied with flow cytometry analysis, scanning and transmission electron microscopy (SEM and TEM), immunogold and immunofluorescence staining techniques. The results showed that estradiol markedly stimulated the division and proliferation of the ER( + ) MCF-7 cells at 10 nM, but had no marked effect on the cell cycle of the ER(-) H466B cells at the same concentration, and that tamo-xifen inhibited the stimulation of estradiol on MCF-7 cells. Estradiol obviously influenced the ultrastruc-ture of MCF-7 cells. Immunocytochemical localization of epidermal growth factor receptor (EGFR) on the MCF-7 cell membrane surface indicated that one of the mechanisms involving the growth of MCF-7 breast cancer cell and the stimulating effect on MCF-7 cells growth by estradiol is autocrine secretion.

Sensitivity Evaluation of Two Human Breast Cancer Cell Lines to Tamoxifen through Apoptosis Induction

Tamoxifen citrate (TAM) has been used to treat breast cancer in women for many years. The com-parative effects of TAM in inducing apoptosis were evaluated in estrogen receptor-positive (ER- positive MCF-7) and estrogen receptor-negative (ER-negative MDA-MB-231) human breast cancer cell lines in vitro in order to determine if these two cell lines differ in their sensitivity to TAM. Mi-tochondrial membrane permeability potential disruption was assessed in both cell lines by a lip-ophilic cationic dye (DePsipher assay, Trevigen, Inc.) utilizing fluorescence microscopy. Using this specific fluorochrome, we were able to associate mitochondrial membrane disruption to early, mid-, and late apoptotic cells. TAM induced cell death via apoptosis in both ER-positive and ER- negative cells, however, apoptosis induction was more pronounced in ER-positive MCF-7 compared to ER-negative MDA-MB-231 breast cancer cells. These findings may have some therapeutic use in the treatment of estrogen dependent and estrogen independent breast cancer.

In Vitro Study on the Effect of Bee Venom on Some Cell Lines and Lumpy Skin Disease Virus

Bee venom （BV） was used from long time ago in the medical field as treatment of chronic joint affections. In the recent decades, the screening process of new sources of antimicrobials discovers its high advantageous characteristics for combating various types of microbes, as well as trials to discover its anti-cancer medicinal fields. Lumpy skin disease virus （LSDV） causes disease in cattle of economic importance, and this work aimed to find treatment as well as alternative inactivant for LSDV. The use of bee venom as antiviral was experimented in this work and exhibited satisfied inhibitory effects on LSDV, meanwhile, the antigenic properties was still intact. The viability of virus was tested in tissue culture cells lines and in embryonated chicken eggs. According to doses and time of exposure, the cell lines of Hep-2 （human larynx carcinoma） and MCF7 （breast carcinoma cell line） were treated with different concentrations of BV and examined after 24 h post-inoculation. The Hep-2 and MCF7 cell lines were treated with various concentrations of BV in descending doses as follow： 25, 20, 15, 10, 5 and 0.5 ug/mL of BV. Then bee venom pathological effects on Hep-2 cells and MCF7 cells were observed, such as apoptosis, retarded growths and cytolysis. The results indicate the possibilities of using bee venom as anti-neoplastic and antiviral.

雷公藤内酯醇通过调控miR-142-3p/HSP70通路抑制人乳腺癌MCF-7细胞增殖、侵袭和迁移

目的:探究雷公藤内酯醇(TP)通过miR-142-3p/HSP70信号通路对人乳腺癌MCF-7细胞恶性生物学行为的影响。方法:常规培养MCF-7细胞,将其分为6组:对照组、TP组、miR-142-3p inhibitor组、TP+inhibitor组、miR-142-3p mimic组和TP+mimic组,用转染试剂将相应的核酸或质粒转染MCF-7细胞。qPCR法、EdU细胞增殖实验、Transwell小室实验、细胞划痕实验、WB法分别检测转染后各组MCF-7细胞中miR-142-3p和HSP70 mRNA的表达,MCF-7细胞的增殖、侵袭、迁移能力和HSP70蛋白表达水平。结果:TP或miR-142-3p过表达能显著促进MCF-7细胞中miR-142-3p和HSP70的表达,敲减miR-142-3p则可明显抑制MCF-7细胞中miR-142-3p和HSP70的表达,TP可逆转由敲减miR-142-3p对MCF-7细胞中miR-142-3p和HSP70表达的影响;TP、过表达miR-142-3p均可明显抑制MCF-7细胞的增殖、迁移和侵袭能力(均P<0.05),敲减miR-142-3p则均可促进MCF-7细胞的增殖、迁移和侵袭能力(均P<0.05),TP可逆转由敲减miR-142-3p对MCF-7细胞恶性生物学行为的影响(均P<0.05)。结论:TP可通过调控miR-142-3p/HSP70信号通路,进而抑制MCF-7细胞的增殖、侵袭和迁移能力。

Study on regulating mechanisms of oxocrebanine obtained from Stephania hainanensis H.S.Lo et Y.Tsoong on microtubule sites and tubulin in human breast cancer MCF-7 cells

Objective:To determine the destructive ability of oxocrebanine,an anti-breast cancer active compound obtained from Stephania hainanensis H.S.Lo et Y.Tsoong,on microtubule network,and investigate the effect of oxocrebanine on microtubule network homeostasis at both molecular and cellular levels.Methods:the EBI site competition method and molecular docking method were used to determine the occupation of the microtubule site of oxocrebanine.Western Blot was used to detect the effect of oxocrebanine on microtubule-associated proteins including STAT3,PAK1,CAMK4,and PKA.Results:The results of EBI site competition assay showed that the binding of EBI toβ-Tubulin covalent fusions produced adducts that appeared in regions of lower molecular weight thanβ-tubulin(ctrl 2).Molecular docking results showed that oxocrebanine could occupy the colchicine site of microtubule proteins.As revealed by Western Blot,the expression of STAT3 protein was decreased after MCF-7 cells have been treated with low,medium,and high concentration of oxocrebanine or the positive drug taxol for 48 h(P<0.01).The expression levels of PAK1 and Camk4 proteins aslo showed significant reductions(P<0.05,or P<0.01).Oxocrebanine also decreased the PKA protein in MCF-7 cells compared to the control group(P<0.01).Conclusions:Oxocrebanine,a ligand that binds at the colchicine site of tubulin,perturbs tubulin polymerization and causes mitosis in MCF-7 cells,thus leading to MCF-7 cell death.Oxocrebanine may promote microtubule dynamics through stathmin by inhibiting the expression levels of STAT3,PAK1,Camk4,and PKA proteins in MCF-7 cells.Oxocrebanine interfers with spindle formation,and ultimately causes mitotic catastrophe in MCF-7 cells.

DCN通过VEGF因子抑制乳腺癌MCF-7细胞增殖的实验研究

目的探讨核心蛋白聚糖(decorin,DCN)通过下调血管内皮生长因子(Vascular endothelial growth factor,VEGF)表达抑制乳腺癌MCF-7肿瘤细胞增殖的分子机制。方法体外培养MCF-7细胞,质粒转染诱导MCF-7细胞高表达核心蛋白聚糖为DCN组,不转染的MCF-7细胞为正常对照组。MTT法、流式细胞术细胞观察各自细胞增殖情况,RT-PCR、Western blot法检测各组细胞VEGF mRNA和蛋白表达变化。结果与对照组比较,流式细胞术检测DCN转染24、48、72 h后DCN组MCF-7细胞数目明显减少(P<0.05),MTT结果显示DCN组细胞增殖能力受到显著抑制(P<0.05),Western blot检测DCN组细胞VEGF蛋白表达水平有下降趋势。结论核心蛋白聚糖通过降低VEGF mRNA表达水平,使细胞内生成的VEGF蛋白减少,抑制MCF-7细胞增殖。

TNF-ɑ调控LRG1促进乳腺癌MCF-7细胞增殖、侵袭和迁移

目的:研究TNF-α对乳腺癌MCF-7细胞中LRG1蛋白表达的调控及其对乳腺癌MCF-7细胞增殖、侵袭和迁移能力的影响及相关分子机制。方法:MTT实验检测不同浓度TNF-α处理后MCF-7细胞活力;EdU实验、Transwell实验和划痕实验分别检测抑制LRG1表达后细胞增殖、侵袭以及迁移能力;Western blot检测细胞内MAPK信号通路中p-p38蛋白表达。结果:低浓度TNF-α处理乳腺癌MCF-7细胞,细胞活力增强;抑制LRG1表达后细胞增殖能力下降,侵袭细胞数、细胞迁移率以及p-p38蛋白表达均下降。结论:TNF-ɑ通过调控LRG1的表达促进乳腺癌MCF-7细胞增殖、侵袭和迁移,这一过程可能通过激活p38MAPK信号通路来实现。

毛酸浆内酯通过抑制STAT3诱导人乳腺癌MCF-7细胞凋亡

[目的]旨在探讨信号转导和转录激活因子3(STAT3)在毛酸浆内酯(PPB)诱导人乳腺癌MCF-7细胞凋亡中发挥的作用。[方法]采用荧光染色法分析PPB诱导MCF-7细胞凋亡;使用生物信息学方法预测PPB抗乳腺癌的潜在机制;采用噻唑蓝(MTT)法考察STAT3抑制剂S3I-201以及STAT3小干扰RNA(siRNA)对PPB抑制MCF-7细胞生长的作用;采用蛋白免疫印迹(Western Blot)法考察PPB单独处理或STAT3 siRNA预处理后对MCF-7细胞中STAT3、B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、半胱氨酸天冬氨酸蛋白酶8(Caspase8)、半胱氨酸天冬氨酸蛋白酶9(Caspase9)、细胞色素c(Cytochrome c)以及多聚ADP核糖聚合酶(PARP)蛋白表达的影响。[结果]MCF-7细胞经PPB作用后凋亡形态特征明显,凋亡比例上升;生物信息学结果显示PPB与乳腺癌疾病的共同靶点STAT3在乳腺癌组织中高表达,单基因GSEA结果提示STAT3高表达与凋亡信号通路呈负相关;Western Blot法检测结果显示PPB能够抑制STAT3的磷酸化;S3I-201抑制剂或siRNA敲降STAT3均能进一步促进PPB抑制MCF-7细胞生长;此外,敲降STAT3进一步增加PPB对促凋亡蛋白Bax、Cytochrome c、裂解的Caspase8(Cleaved-Caspase8)、裂解的Caspase9(Cleaved-Caspase9)以及裂解的PARP(Cleaved-PARP)的促进作用,并增加PPB对抗凋亡蛋白Bcl-2的抑制作用。[结论]PPB通过抑制STAT3诱导人乳腺癌MCF-7细胞凋亡。

香豆酸诱导MCF-7细胞凋亡的代谢与氧化应激影响

目的 探讨香豆酸诱导乳腺癌细胞MCF-7凋亡的机制及氧化应激与代谢的影响。方法 采用氧化相关蛋白活性研究香豆酸对MCF-7氧化应激的影响;液相质谱仪结合代谢组学探索香豆酸对MCF-7细胞代谢的影响。结果 香豆酸呈浓度依赖式对MCF-7细胞凋亡具有一定的促进作用,并上调细胞的氧化应激性导致MCF-7细胞氧化系统失衡;同时香豆酸影响MCF-7的细胞代谢,主要是体现糖代谢,富集显著通路集糖酵解;并筛选到差异代谢物563个,其中上调463个,下调100个。结论 香豆酸诱导MCF-7细胞凋亡作用机制可能是通过影响细胞的氧化应激性以及调控细胞糖代谢来实现。

羟基积雪草酸对乳腺癌MCF-7细胞增殖、凋亡和自噬的影响

目的探讨羟基积雪草酸(madecassic acid,MA)对乳腺癌MCF-7细胞增殖、凋亡及自噬的影响。方法将MCF-7细胞分为阴性对照组、不同浓度的MA(80、100、120、140、160μmol/L)组、不同浓度的他莫昔芬(10、20、30、40、50、35μmol/L)组,干预24、36、48 h。初步确定MA发挥抗乳腺癌作用的最佳浓度和最佳时间后,采用MTT法检测细胞活力,计算相应的半抑制浓度(half maximal inhibitory concentration,IC50)值;流式细胞术检测细胞凋亡;JC-1荧光探针检测线粒体膜电位变化;Western blot法检测细胞增殖蛋白细胞核抗原蛋白(proliferating cell nuclear antigen,PCNA)、自噬蛋白苄氯素-1(Beclin-1)、微管相关蛋白1轻链3-Ⅱ/Ⅰ(microtubule-associated protein1 light chain 3Ⅱ/Ι,LC3Ⅱ/Ι)、螯合体1(protein 62,p62)的蛋白相对表达水平。透射电镜检测自噬小体。结果发挥抗肿瘤作用的他莫昔芬最佳浓度为35μmol/L,MA最佳浓度为140μmol/L,最佳时间均为48 h。与阴性对照组相比,MA140μmol/L组和他莫昔芬35μmol/L组的细胞凋亡率,细胞荧光相对强度以及LC3Ⅱ/Ⅰ、Beclin-1蛋白相对表达水平均升高(P<0.05,P<0.01);PCNA、P62蛋白相对表达水平降低(P<0.05,P<0.01)。与MA 140μmol/L组相比,他莫昔芬35μmol/L组细胞凋亡率、细胞荧光相对强度以及Beclin-1蛋白相对表达水平明显升高(P<0.01),PCNA蛋白相对表达水平明显降低(P<0.01)。阴性对照组MCF-7细胞膜完整,核膜清晰,细胞形态良好;MA 140μmol/L组细胞膜、细胞核形态不规则,线粒体基质密度较高、嵴扩张,可见自噬小体;他莫昔芬35μmol/L组细胞膜局部溶解、破损,可见双核仁,线粒体肿胀、基质溶解,可见自噬小体。结论MA可抑制乳腺癌MCF-7细胞的增殖、诱导细胞凋亡和自噬。

Effect of 1,25(OH)_2D_3 on the growth and apoptosis of breast cancer cell line MCF-7

Objective To study the effect of 1,25 dihydroxyvitamin D 3 (1,25(OH) 2D 3) on the growth and apoptosis of breast cancer cell line MCF 7 Methods Cell number was determined using the MTT method Flow cytometric analysis was performed on cell cycles, and the percentage of apoptosis was counted Apoptotic cells were quantified by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL), and bcl 2 protein expression was estimated with Western blotting Results After incubation with 1,25(OH) 2D 3 10 7 mol/L for 48 hours, MCF 7 cells exhibited significant growth in a dose and time dependent manner Flow cytometric analysis indicated that cell numbers in G 0/G 1 increased along with increasing apoptotic peak and percentage With microscope and electron microscope observation, characteristics of apoptosis such as typical apoptotic bodies were commonly found TUNEL also showed that 1,25(OH) 2D 3 10 8 mol/L and 10 7 mol/L groups had significantly high apoptosis percentage than control group with dose dependence on induction apoptosis And Western blot showed that 1,25(OH) 2D 3 10 8 mol/L could down regulate bcl 2 protein and 10 7 mol/L could almost block bcl 2 protein expression Conclusions 1,25(OH) 2D 3 can inhibit cell growth with G 0/G 1 arrest, enhance the proliferation inhibition action of adriamycin, and induce apoptosis which may result from the down regulation of the anti apoptotic bcl 2 protein