线粒体融合素基因-2对乳腺癌细胞凋亡的影响

目的研究外源性线粒体融合素基因-2(mfn2)对乳腺癌细胞(MCF-7)凋亡的影响。方法在阳离子聚合物的介导下将含有mfn2 cDNA的质粒在体外转染MCF-7,蛋白印记法(Western blot)检测绿色荧光蛋白(GFP),MTT法检测mfn2对MCi-7细胞增殖的影响。采用Annexin-V/PI双标记法检测转染前后细胞凋亡的变化,JC-1标记细胞线粒体,在流式细胞仪上检测线粒体跨膜电位(△ψm)的变化,电镜观察超微结构的变化。结果转染mfn2基因的MCF-7细胞可以稳定高表达GFP蛋白。MTT实验提示,转染mfn2 cDNA后,MCF-7细胞增殖明显受到抑制,转染mfn2 cDNA后48 h,△ψm下降。与转染pEGFlP组和空白对照组相比,转染pEGFP mfn2组明显促进凋亡,其凋亡率分别为:转染组16.0%,转染空质粒组3.6%,空白对照组4.8%(P<0.05)。电镜观察显示,mfn2使线粒体嵴断裂、消失、基质疏松,肿胀的线粒体围绕在核周呈密集排列。结论mfn2基因在体外转染MCF-7细胞,细胞线粒体膜电位降低,线粒体嵴断裂、消失,细胞凋亡明显增加。     

小白菊内酯体外杀伤小鼠乳腺癌肿瘤干细胞的研究*

目的:探讨小白菊内酯（PTL）在体外对小鼠乳腺癌肿瘤干细胞（CSC）的影响。方法:无血清微球体悬浮培养乳腺癌细胞系4T1 细胞,以富集乳腺癌CSC ,以第10代微球体细胞作为实验细胞,实验分为对照组、5-FU 组、PTL 组、5-FU+PTL组、PTL+NAC（N-乙酰半胱氨酸）组。首先按不同分组加入药物,然后以无血清培养基培养,7 天后观察细胞的成球情况,并收集细胞检测CD44+CD24-/low细胞的含量、无荧光染色侧群（SP）细胞比例、耐药基因MDR1、BCRP mRNA表达。结果:无血清悬浮培养可以富集4T1 细胞系中的CSC ,CD44+CD24-/low细胞比例可达（68.9 ± 3.78）% 。药物处理后,对照组、5-FU 组、PTL+NAC组细胞可形成明显的细胞球,PTL 组形成的细胞球很少,5-FU+PTL组无存活细胞。对照组、5-FU 组、PTL 组、PTL+NAC组CD44+CD24-/low细胞含量分别为（71.2 ± 2.3）% 、（75.6 ± 3.1）% 、（10.3 ± 1.9）% 、（58.1 ± 2.6）% ;无荧光染色细胞（SP）细胞百分比分别为（56.7 ± 3.4）% 、（62.0 ± 2.7）% 、（8.1 ± 1.1）% 、（51.5 ± 2.3）% ,PTL 组明显低于其它3 组,具有统计学差异（P<0.01）。 5-FU 组、PTL 组、PTL+NAC组MDR1 和BCRP与对照组相比较,基因相对表达量分别为1.16± 0.21、1.09± 0.13、0.22± 0.15和0.27± 0.11、0.89± 0.18、0.93± 0.14,PTL 组明显低于其它3组,具有统计学差异（P<0.01）。 结论:PTL 可以靶向作用于乳腺癌CSC ,改变CSC 的增殖状态,使培养细胞中CSC 含量明显降低。抗氧化剂NAC 可以明显拮抗PTL 这种作用。      

小白菊内酯对胃癌BGC823细胞凋亡表型的影响

目的:探讨小白菊内酯对胃癌BGC823凋亡表型影响.方法:MTT法检测BGC823增殖能力的变化,同时在倒置显微镜下观察细胞形态;采用流式细胞仪检测细胞线粒体膜电位的变化; ELISA法检测caspase-3活性;western blot法检测细胞Bcl-2表达.结果:Par以浓度和时间依赖方式抑制胃癌细胞增殖,镜下可见细胞凋亡形态学改变 .经Par 处理后,随着Par浓度增加,细胞线粒体膜电位逐渐下降,经100μmol/L Par处理6h后,细胞caspase-3活性增加, 24h后下降, 至48h仍保持在高水平,western blot法检测到细胞Bcl-2表达下调.结论: Par通过下调Bcl-2和上调caspase-3活性来诱导细胞凋亡.     

小白菊内酯对不同环氧合酶-2表达的鼻咽癌细胞株中干性侧群细胞转归的影响

目的：探讨倍半萜烯内酯（sesquiterpene Iactones,SLs）类化合物对不同环氧合酶-2（cyclooxygenase-2,COX-2）表达水平的人鼻咽癌（nasopharyngeal carcinoma,NPC）细胞中癌干细胞（cancer stem cells,CSCs）转归的影响。方法：分别采用实时定量PCR（qRT-PCR）和Western blot检测人鼻咽癌高分化CNE1L和低分化CNE2L细胞株中COX-2 mRNA和蛋白本底表达水平。给予不同剂量SLs活性成分小白菊内酯（parthenolide,PN）处理2种细胞株后,再分别采用噻唑蓝（MTT）法测定细胞增殖活性;qRT-PCR检测细胞中干性相关基因COX-2、ABCG2、BMI1、OCT4 mRNA水平;流式细胞术分析干性侧群（side population,SP）细胞的相对含量;平板克隆集落形成实验检测干性细胞的自我更新和分化增殖能力。结果：CNE1L和CNE2L细胞中COX-2 mRNA和蛋白本底水平显著不同,在CNE1L细胞中明显高于CNE2L细胞（P〈0.05）;与对照组比较,PN处理后,细胞增殖抑制率随PN浓度（10～100μmol/L）增加呈剂量依赖性增高（P〈0.05）,细胞中COX-2 mRNA在CNE1L中升高、在CNE2L中降低,干性相关基因ABCG2、BMI1 mRNA在CNE1L细胞中升高、而OCT4 mRNA在两株细胞中均降低（P均〈0.05）;SP细胞抑制率亦随PN浓度（2.5～40μmol/L作用24 h）增加呈剂量依赖性增高（P〈0.05）;而细胞的集落形成能力随PN浓度（0.25～1.5μmol/L作用72 h）增加显著降低（P〈0.05）;上述结果在CNE1L和CNE2L细胞株间差异均有统计学意义（P〈0.05）,在CNE1L细胞中变化作用更强。结论：PN对不同NPC细胞株中的干性细胞功能具有抑制作用且存在明显差别,可能与不同细胞间COX-2表达的差异性有关。     

RUNX3基因真核表达载体的构建及其在乳腺癌T47D细胞中的表达

目的：构建真核表达载体pcDNA3.1（＋）-RUNX3,并在乳腺癌T47D细胞株中表达。方法：应用基因重组技术和限制性内切酶EcoRI和XhoI酶切,构建并鉴定pcDNA3.1（＋）-RUNX3真核表达载体,经脂质体Lipofectamine2000介导质粒转染T47D细胞后应用逆转录-聚合酶链反应（RT-PCR）和Western blot实验,检测RUNX3在T47D细胞中的表达。结果：重组真核表达载体pcDNA3.1（＋）-RUNX3经限制性内切酶EcoRI和XhoI酶切,电泳后显示1.3kb的RUNX3目的片段和5.4kb的pcDNA3.1（＋）载体片段。测序证实酶切片段与gene bank中登记的RUNX3序列相同,证实pcDNA3.1（＋）-RUNX3真核表达载体构建成功。经RT-PCR和Western blot检测,表明转染pcDNA3.1（＋）-RUNX3的T47D细胞RUNX3阳性表达。结论：重组真核表达载体构建正确,并建立稳定表达RUNX3的T47D细胞系,从而为后续研究提供有用的细胞研究模型。     

RUNX3基因真核表达载体的构建及其在乳腺癌T47D细胞中的表达

目的:构建真核表达载体pcDNA3.1(+)-RUNX3,并在乳腺癌T47D细胞株中表达。方法:应用基因重组技术和限制性内切酶EcoRI和XhoI酶切,构建并鉴定pcDNA3.1(+)-RUNX3真核表达载体,经脂质体Lipofectamine2000介导质粒转染T47D细胞后应用逆转录-聚合酶链反应(RT-PCR)和Western blot实验,检测RUNX3在T47D细胞中的表达。结果:重组真核表达载体pcDNA3.1(+)-RUNX3经限制性内切酶EcoRI和XhoI酶切,电泳后显示1.3kb的RUNX3目的片段和5.4kb的pcDNA3.1(+)载体片段。测序证实酶切片段与gene bank中登记的RUNX3序列相同,证实pcDNA3.1(+)-RUNX3真核表达载体构建成功。经RT-PCR和Western blot检测,表明转染pcDNA3.1(+)-RUNX3的T47D细胞RUNX3阳性表达。结论:重组真核表达载体构建正确,并建立稳定表达RUNX3的T47D细胞系,从而为后续研究提供有用的细胞研究模型。     

线粒体融合素基因-2对人乳腺癌MCF-7细胞株增殖与化疗敏感性的影响

背景与目的:线粒体融合素基因-2(mitofusin-2 gene,mfn2)是作用于线粒体外膜的一种增殖抑制基因,mfn2过表达可抑制血管平滑肌细胞的增殖.本研究探讨外源性mfn2对人乳腺癌细胞MCF-7增殖以及化疗敏感性的影响.方法:将含有mfn2 cDNA的质粒在阳离子聚合物的介导下体外转染MCF-7细胞,Western blot法检测绿色荧光蛋白(green fluorescent protein,GFP)的表达,细胞计数及MTT法检测mfn2对MCF-7细胞增殖的影响,流式细胞术检测MCF-7细胞周期分布及喜树碱处理前后细胞凋亡的变化.结果:转染mfn2基因的MCF-7细胞可以稳定高表达GFP.MTT实验提示转染mfn2 cDNA后,MCF-7细胞增殖明显受到抑制,DNA直方图显示细胞停滞于S期,转染mfn2 cDNA组S期细胞比率为(42.7±1.3)%,高于转染空质粒组的(17.2 2.0)%和空白对照组的(19.6±1.7)%(P＜0.05).mfn2基因转染后诱导的细胞凋亡率从(3.6±0.6)%升高到(16.0±0.3)%;加入喜树碱4 h后转染mfn2基因的细胞凋亡率为(69.6 4.3)%,高于转染空质粒组的(31.0±1.8)%和空白对照组的(23.4 2.8)%(P＜0.05).结论:转染mfn2基因可以明显抑制MCF-7细胞的增殖,增强MCF-7细胞对喜树碱的敏感性.     

黄荆子乙酸乙酯提取物对人乳腺癌T47D细胞及其裸鼠移植瘤生长抑制的影响

目的:研究黄荆子乙酸乙酯提取物(EVn-50)对人乳腺癌(T47D)细胞及其裸鼠移植瘤生长抑制的影响.方法:体外培养T47D细胞,溴化标记尿嘧啶(BrdU)掺入法测定细胞核酸合成的抑制作用;平皿克隆形成法测定细胞锚定依赖生长能力的抑制作用;人乳腺癌T47D裸鼠移植瘤模型治疗实验,观察EVn-50在体内对T47D细胞生长抑制作用,HE染色观察乳腺癌组织和细胞形态改变.结果:EVn-50抑制体外培养T47D细胞核酸合成和生长,呈剂量依赖性;EVn-50对裸鼠移植瘤的生长具有显著抑制作用,呈剂量和时间依赖性;EVn-50 80 mg/ kg实验组对移植瘤的瘤重抑制率为51.4% (P<0.001);镜下观察EVn-50 80 mg/ kg实验组肿瘤组织坏死组织较多,细胞异型性较少.结论:黄荆子乙酸乙酯提取物对人乳腺癌有生长抑制作用.     

小白菊内酯及顺铂对人结肠癌细胞SW620凋亡和增殖的作用

[目的]探讨小白菊内酯及顺铂对人结肠癌细胞SW620增殖及凋亡的影响.[方法]不同浓度的小白菊内酯和顺铂分别处理SW620细胞,MTr法检测细胞增殖的变化情况,流式细胞仪检测细胞凋亡的情况.[结果]小白菊内酯和顺铂对SW620细胞增殖均具有抑制作用;分别作用48h后,小白菊内酯和顺铂对SW620细胞增殖的抑制作用呈浓度依赖性;5 μmol/L顺铂联合10μmol/L小白菊内酯作用SW620细胞时,对细胞增殖具有协同抑制作用.小白菊内酯和顺铂可以诱导SW620细胞凋亡.[结论]小白菊内酯和顺铂联用具有协同作用,能抑制SW620细胞增殖并诱导细胞凋亡.     

Biphasic effect of medroxyprogesterone-acetate (MPA) treatment on proliferation and cyclin D1 gene transcription in T47D breast cancer cells

While progesterone is a known differentiation-inducing factor in the human endometrium, for the breast epithelium both proliferation-inducing and -inhibiting effects have been described. Cyclin D1, which is required for cell cycle progression in G1 and has been shown to play an important role in the pathogenesis of breast cancer has been implicated as a possible mediator of such effects. In the present study we thus investigated the effects of the progestin agonist MPA (medroxy-progesterone acetate) on proliferation of T47D breast cancer cells. In parallel experiments, the regulation of the human cyclin D1 promoter as well as cyclin D1 protein levels under the influence of MPA were studied. Our results show an increase of proliferative activity in T47D cells after 24 and 48 h of MPA treatment followed by inhibition of proliferation after 72 h. In Western blot analysis an increased expression level of cyclin D1 protein can be observed after 24h of MPA stimulation, while at 72h the protein levels are barely detectable. Transient transfection experiments with a luciferase reporter plasmid containing the human cyclin D1 promoter showed an induction of the promoter after 24 and 36h of MPA treatment followed by a reduction in promoter activity. In conclusion, our results confirm the existence of a biphasic response of T47D cell proliferation in response to MPA treatment, consisting of stimulation of proliferation followed by inhibition, and further implicate cyclin D1 as a mediator of these effects, since the cyclin D1 promoter shows a similar biphasic response in this context.     

小白菊内酯体内杀伤小鼠乳腺癌肿瘤干细胞

目的： 探讨小白菊内酯（parthenolide,PTL）对小鼠乳腺癌肿瘤干细胞（cancer stem cell,CSC）的杀伤作用,为临床应用PTL治疗乳腺癌提供实验依据。 方法： 采用5-氟尿嘧啶（5-fluorouracil, 5-FU）化疗法制备富含CSC的小鼠4T1细胞乳腺癌模型,随机分为对照组、5-FU组、PTL组。4周后脱颈处死小鼠,检测各组小鼠肿瘤的体积和重量,流式细胞术检测小鼠肿瘤组织中CD44+CD24-/low细胞比例,Hoechst33342染色法检测侧群（side population,SP）细胞的比例,免疫组化法检测CD55和乙醛脱氢酶1（aldehyde dehydrogenase1,ALDH1）蛋白的表达,倒置显微镜观察乳腺癌细胞微球体的形成。 结果： 成功制备富含CSC的小鼠乳腺癌细胞移植瘤模型,PTL可下调小鼠肿瘤组织中CD44+CD24-/low细胞的比例\[（42.5±3.7）% vs （68.7±32）%,P<0.05\],有效降低荷瘤小鼠肿瘤组织中SP细胞的比例\[（39.2±1.8）% vs （61.3±2.6）%,P<0.05\],下调小鼠移植瘤组织中CD55和ALDH1蛋白的表达\[（18.9±1.5）% vs （30.1±1.3）%,（8.1±2.3）% vs （18.0±1.4）%;均P<0.05\],抑制小鼠肿瘤细胞在无血清培养条件下形成微球体,并可抑制小鼠移植瘤的体积和重量\[（0.625±0.159）cm3 vs （1.715±0184）cm3,（1.467±0.373）g vs （3.367±0.398）g;均P<0.05\]。 结论： PTL在荷瘤小鼠体内可以明显降低肿瘤组织CSC含量,提示PTL可用来靶向杀伤乳腺癌CSC。     

Estrogen and rapamycin effects on cell cycle progression in T47D breast cancer cells

The contribution of estrogen (and progesterone) in driving cell cycle progression of hormone dependent breast cancer cells is well documented, however, the roles of the various relevant signal transduction pathways remain unclear. The immunosuppressant rapamycin is a potent inhibitor of cell cycle progression and has been used to define signal transduction pathways. In this study we have determined rapamycin's effects on cell cycle progression in estrogen dependent breast cancer cells using a novel method of inducing S-phase. In this method estradiol-17- alone induced S-phase without mitogen support. In our studies the T47D cells were quite sensitive to estradiol-17-, with half-maximal induction in the picomolar range, indicating that the estrogen can induce S-phase in the absence of mitogens such as insulin. The estrogen response does not seem to be particularly specific because estriol estrone and estradiol-17--BSA were about as effective as estradiol-17-. R5020, a progestin also induced S-Phase, while rapamycin blocked steroid driven transition of cells from G₁ to S-phase.     

Expression of insulin-like growth factor binding proteins by T-47D human breast cancer cells: regulation by progestins and antiestrogens

Summary We have used ligand blotting and Northern blotting techniques to examine the effects of progestins and antiestrogens on expression of insulin-like growth factor binding proteins (IGFBPs) by T-47D human breast cancer cells under conditions where these agents are growth inhibitory. Under basal conditions, conditioned medium from T-47D cells was found to contain IGFBPs of 39, 33, and 27 kDa. Northern blot and/or Western blot analysis have identified these as IGFBP 2, 5, and 4, respectively. Medroxyprogesterone acetate (MPA) treatment resulted in a time- and dose-dependent decrease in IGFBP 4 and 5 mRNA abundance and secretion of these proteins, while little if any effect was observed on IGFBP 2 expression. A decrease in the steady state mRNA levels for IGFBP 4 and 5 was observed with as little as 0.1 nM MPA. Using 10 nM MPA a maximum decrease in IGFBP 4 and 5 mRNA levels was observed between 12 and 24 hours. While RU 486 alone had little or no effect on IGFBP 4 expression, it inhibited the effect of MPA. However, in the same samples, IGFBP 5 expression was inhibited by RU 486, and RU 486 was unable to reverse the effects of progestins on the expression of IGFBP 5. Furthermore, another synthetic progestin, Org 2058, but not dexamethasone, inhibited IGFBP 4 and IGFBP 5 expression. The antiestrogen ICI 164384 also transiently decreased the steady state mRNA levels of both IGFBP 4 and IGFBP 5. Regulation of expression of the IGFBPs by these agents suggests a potential role for the IGFBPs in the growth response of T-47D cells to these agents.     

Apoptotic mechanisms in T47D and MCF-7 human breast cancer cells

To investigate the mechanisms underlying apoptosis in breast cancer cells, staurosporine was used as an apoptotic stimulus in the human breast cancer cell lines MCF-7 and T47D. Staurosporine induced dose and time dependent increases in DNA fragmentation which was abrogated by z-VAD-fmk. MCF-7 cells did not express caspase-3, suggesting that DNA fragmentation occurred in the absence of caspase-3 and that other caspases may be involved. Staurosporine induced DEVDase activity in T47D cells suggesting the involvement of caspase-3 and/or caspase-7, yet there was no DEVDase activity in MCF-7 cells, probably ruling out the involvement caspase-7. However, staurosporine induced the cleavage of pro-caspase-6 in MCF-7 cells, but not in T47D cells. Caspase dependent PARP cleavage was detected in MCF-7 cells at 3 h, whereas only partial PARP cleavage was detected in T47D cells and then only after 24 h. Moreover, staurosporine led to cytochrome c release at 2 h in MCF-7 cells and 6 h in T47D cells. In addition, a time dependent and caspase-independent reduction of the mitochondrial transmembrane potential was observed; which appeared to occur after the release of cytochrome c. Translocation of Bax from the cytosol to mitochondria was observed in both cell types, and this preceded cytochrome c release in both T47D and MCF-7 cells. Apoptotic events in both cell types differ temporally, involving activation of different caspases and mitochondrial changes.     

Prostate-specific antigen induction by a steroid hormone in T47D cells growing in SCID mice

Previous studies revealed that prostate-specific antigen (PSA) is present in > 30% of human breast tumor cytosols. Survival analysis showed that patients with PSA-producing tumors have a reduced risk for relapse, suggesting PSA to be an independent favorable prognostic marker for a large subset of breast cancer patients. The present investigation established an in vivo model for the induction of PSA in human breast cancer tumors growing as xenografts in severe combined immunodeficient (SCID) mice. The human mammary cancer cell-line T47D was grown i.m. in female mice. When the tumor and leg diameter reached 10 mm, the mice were stimulated daily with norgestrel for either 5 or 7 days to produce PSA, and sacrificed on day 8. The prostate cancer cell-line LNCaP was grown in male mice and functioned as a positive control for PSA production. After T47D and LNCaP mice were sacrificed, a highly sensitive immunofluorometric assay was used to analyze the PSA concentration in the tumor, muscle, liver, and kidney cytosols. Norgestrel-stimulated T47D mice showed significantly more PSA in the tumors compared to tumors of the control mice. However, PSA levels in tumors of the stimulated mice were significantly lower than those in the LNCaP xenografts. No PSA levels above background were present in the blood and normal tissue of the norgestrel-stimulated or control T47D xenografts. This mouse model will be a valuable tool for investigating and screening new therapies for a subgroup of breast cancer patients who have significant PSA concentrations in their tumors.     

Pregnane Steroids from the Leaves of Melia Azedarach and Apoptotic Activity against T47D Cells

Objective: Nature has provided us with many pharmaceutical resources so far. Breast cancer shows an increasing trend in the world for the last decade and becomes one of five leading causes of death. Among the plants, Melia azedarach L. has been used widely in traditional medicine for many ailments including breast cancer. Following our previous findings that the ethyl acetate fraction was the most active cytotoxic fraction against T47D cells, we aimed to isolate the cytotoxic compounds and further elucidate their apoptotic mechanisms. Methods: The compounds were isolated through a series of chromatography with cytotoxicity evaluations. Identification of the isolated compounds was achieved by intensive spectroscopic analysis such as NMR, MS, and IR spectra. Cytotoxicity was evaluated by MTT method using doxorubicin as a reference compound. The expression of apoptosis-related factors was quantified by flow cytometry and immunocytochemistry. Results: Two isomers of pregnane steroids with molecular weight 330.2087 (C21H30O3) were isolated from the EtOAc extract. Spectroscopic analysis revealed the structures as 17-ethylene-3,4-dihydroxy-14-methyl-18-norandrostene-16-one (1) and 17-ethylene-3,4-dihydroxy-5-pregnene-16-one (2), respectively. These compounds showed moderate cytotoxicity (IC50 172.9 and 62.2 µg/mL, respectively) comparable to doxorubicin (IC50 3.08 µg/mL). The execution of apoptosis may be related to the increase of the ratio of BAX/bcl-2 of the cells.  Conclusion: The EtOAc fraction of Melia azedarach L. leaves and the isolated 5-pregnene-16-one steroids are promising reagents for breast cancer treatment by introducing apoptosis to tumor cells. However, further researches are required to highlight its safety and usage in vivo.     

Secretion of breast gross cystic disease fluid proteins by T47D breast cancer cells in culture — modulation by steroid hormones

Summary The effect of steroid hormones on modulating the secretion rates of three human breast gross cystic disease fluid proteins (GCDFP-15, GCDFP-24, and GCDFP-44) by T47D breast carcinoma cells in tissue culture was evaluated. Androgens (dihydrotestosterone or fluoxymesterone) were capable of stimulating the secretion rates for all three GCDFP's while showing a minimal trend toward slowing the growth rate of T47D cells. This is the first study which shows that androgens can specifically stimulate all three of the major breast GCDFP's concomitantly. Progesterone, and three synthetic progestins, all showed inhibition of the growth rate of T47D cells while causing enhancement of the secretion of GCDFP-15 and GCDFP-44, and only minimal effect on the secretion rate of GCDFP-24. Estradiol was essentially neutral to the growth rate of the T47D cells in our test system. Estradiol did cause a mild enhancement of GCDFP-44 secretion rate, with no appreciable effect on GCDFP-15 or GCDFP-24 secretion rates. These findings suggest that an androgenic stimulus may be involved in the secretion of GCDFP's associated with breast gross cystic disease.     

维生素D对乳腺癌细胞及乳腺癌干细胞凋亡的影响

目的:探究维生素D对人乳腺癌细胞及乳腺癌干细胞凋亡的影响。方法:MTT法检测维生素D对乳腺癌SUM159细胞活力的影响;Hoechst33258染色检测维生素D对乳腺癌SUM159细胞凋亡的影响;实时定量PCR法检测维生素D对乳腺癌SUM159细胞凋亡相关分子Bax和Bcl-2 mRNA表达水平的影响;无血清悬浮培养法（serum-free medium,SFM）富集乳腺癌干细胞,显微镜下观察维生素D对乳腺癌干细胞球大小和数量的影响;实时定量PCR法检测维生素D对乳腺癌干细胞凋亡相关分子Bax、Bcl-2 mRNA表达水平的影响。结果:MTT法检测结果显示,维生素D可显著抑制乳腺癌细胞活力,且随着维生素D浓度升高,乳腺癌SUM159细胞活力的下降具有一定的剂量依赖效应,单因素方差分析显示,差异具有统计学意义(P＜0.01);Hoechst33258染色结果显示,维生素D可诱导乳腺癌SUM159细胞发生细胞凋亡形态改变;进一步PCR法检测结果显示,维生素D可显著上调乳腺癌SUM159细胞促凋亡蛋白Bax mRNA的表达,下调抗凋亡蛋白Bcl-2 mRNA的表达,单因素方差分析显示,差异具有统计学意义(P＜0.01)。SFM培养可有效富集乳腺癌干细胞,维生素D干预可明显抑制SFM富集的乳腺癌干细胞球的大小和数量,且与对照组相比,维生素D可显著上调乳腺癌干细胞球Bax mRNA的表达水平,下调Bcl-2 mRNA的表达水平,单因素方差分析显示,差异具有统计学意义(P＜0.01)。结论:维生素D可抑制乳腺癌细胞及乳腺癌干细胞活力,诱导乳腺癌细胞凋亡。