Anticancer Activity of Camel Milk via Induction of Autophagic Death in Human Colorectal and Breast Cancer Cells

Background/ Objective: Camel milk is traditionally known for its human health benefits and believed to be a remedyfor various human ailments including cancer. The study was aimed to evaluate the inhibitory effects of commerciallyavailable camel milk on cancer cells and its underlying mechanism(s). Materials and Methods: Two cell lines:colorectal cancer HCT 116 and breast cancer MCF-7 were cultured with different doses of camel milk. The effects ofcamel milk on cell death were determined by MTT assay, viability by trypan blue exclusion assay and migration by invitro scratch assay. The mechanism was elucidated by western blotting and confocal microscopy was used to confirmautophagy. Results: Camel milk significantly reduced proliferation, viability as well as migration of both the cells.The accumulation of LC3-II protein along with reduction in expression of p62 and Atg 5-12, the autophagy proteinsimplied induction of autophagy. The (GFP)-LC3 puncta detected by confocal microscopy confirmed the autophagosomeformation in response to camel milk treatment. Conclusion: Camel milk exerted antiproliferative effects on humancolorectal HCT 116 and breast MCF-7 cancer cells by inducing autophagy.     

JS-K, a nitric oxide-releasing prodrug, induces breast cancer cell death while sparing normal mammary epithelial cells

Targeted therapy with reduced side effects is a major goal in cancer research. We investigated the effects of JS-K, a nitric oxide (NO) prodrug designed to release high levels of NO when suitably activated, on human breast cancer cell lines, on non-transformed human MCF-10A mammary cells, and on normal human mammary epithelial cells (HMECs). Cell viability assay, flow cytometry, electron microscopy, and Western blot analysis were used to study the effects of JS-K on breast cancer and on mammary epithelial cells. After a 3-day incubation, the IC50s of JS-K against the breast cancer cells ranged from 0.8 to 3 μM. However, JS-K decreased the viability of the MCF-10A cells by only 20% at 10-μM concentration, and HMECs were unaffected by 10 μM JS-K. Flow cytometry indicated that JS-K increased the percentages of breast cancer cells under-going apoptosis. Interestingly, flow cytometry indicated that JS-K increased acidic vesicle organelle formation in breast cancer cells, suggesting that JS-K induced autophagy in breast cancer cells. Electron microscopy confirmed that JS-K-treated breast cancer cells underwent autophagic cell death. Western blot analysis showed that JS-K induced the expression of microtubule light chain 3-II, another autophagy marker, in breast cancer cells. However, JS-K did not induce apoptosis or autophagy in normal human mammary epithelial cells. These data indicate that JS-K selectively induces programmed cell death in breast cancer cells while sparing normal mammary epithelial cells under the same conditions. The selective anti-tumor activity of JS-K warrants its further investigation in breast tumors.     

贝母素乙通过调控PI3K/Akt信号通路诱导乳腺癌MCF-7细胞凋亡

目的：探究贝母素乙（Peiminine）对乳腺癌细胞MCF-7细胞凋亡的影响及其可能作用机制。方法：采用不同浓度贝母素乙或联合PI3K抑制剂LY294002干预MCF-7细胞,MTT法检测细胞增殖能力;Hoechst33258染色和Annexin V-FITC/PI流式细胞术检测细胞凋亡情况;JC-1染色法检测细胞线粒体膜电位变化;Western blotting检测细胞中PI3K(p110α)、Akt、p-Akt(ser473)、Bad、Bax、Bcl-2、cleaved-Caspase-3以及线粒体和胞浆中细胞色素C(Cyt C)等蛋白表达水平。结果：贝母素乙可呈时间-浓度依赖性抑制MCF-7细胞增殖,诱导细胞出现凋亡形态改变,促进细胞凋亡,并降低线粒体膜电位,上调细胞中Bad、Bax、cleaved-Caspase-3及胞浆中Cyt C蛋白表达水平,下调PI3K(p110α)、p-Akt、Bcl-2和线粒体中Cyt C蛋白表达水平,而Akt蛋白表达水平无显著变化。然而,联合LY294002干预可增强贝母素乙对MCF-7细胞凋亡的促进作用。结论：贝母素乙可诱导乳腺癌MCF-7细胞凋...     

1，6二磷酸果糖增强蛋白酶体抑制剂对人乳腺癌细胞MCF-7的抑瘤效应

目的探讨抑制蛋白酶体活性是否可以诱导人乳腺癌细胞MCF-7的自我吞噬,1,6二磷酸果糖对自我吞噬的影响及自我吞噬对细胞增殖的作用。方法采用MTT法检测细胞增殖,蛋白质印迹检测自我吞噬相关蛋白LC3的表达。结果蛋白酶体抑制剂硼替佐米以剂量依赖方式抑制MCF-7细胞的增殖并诱导细胞的自我吞噬,但是,当1,6二磷酸果糖与硼替佐米联合应用后,可逆转硼替佐米诱导的自我吞噬并增强硼替佐米对MCF-7细胞的增殖抑制。结论蛋白酶体活性的抑制可诱导人乳腺癌细胞MCF-7的自我吞噬代偿性激活,1,6二磷酸果糖可抑制激活的自我吞噬,其与硼替佐米的联合应用可增强其抑瘤效应。     

GANT61通过自噬性细胞死亡抑制人乳腺癌MCF-7细胞增殖

 目的 观察Hedgehog通路抑制剂GANT61对人乳腺癌MCF-7细胞的抑制作用。方法 GANT61作用MCF-7细胞后,通过流式细胞术检测细胞死亡;提取处理细胞总RNA和蛋白。分别采用Real-timePCR和Western blot检测Hedgehog通路SHH、Gli1、Gli2及自噬标志物LC3-Ⅱ表达;处理细胞固定后通过电子显微镜观察GANT61诱导的自噬体形态;自噬抑制剂3-MA处理细胞或自噬相关基因atg5 siRNA转染细胞后再用GANT61作用,流式细胞术检测细胞死亡数量。结果 GANT61能明显诱导MCF-7死亡,降低Hedgehog通路SHH、Gli1、Gli2表达水平,提高LC3-Ⅱ蛋白表达,并可诱导MCF-7细胞产生自噬体。3-MA及atg5 siRNA可减弱GANT61诱导的细胞死亡。结论 GANT61通过诱导自噬性细胞死亡机制发挥抗乳腺癌细胞活性。     

Apogossypolone induces autophagy and apoptosis in breast cancer MCF-7 cells in vitro and in vivo

Objective

Apogossypolone (ApoG2), a new derivative of gossypol, is a potent cell-growth inhibitor. ApoG2 has been demonstrated to have superior anti-tumor activity than gossypol in Bcl-2 transgenic mice. The purpose of this study was to investigate the inhibitory effect of ApoG2 on breast cancer cell line MCF-7 in vitro and in vivo, and to investigate its anti-tumor mechanism.

Methods

MCF-7 cell line in culture was treated with ApoG2. The inhibitory effects of ApoG2 on cell growth were measured by MTT and colony-formation assay. The cell apoptotic rate and cell cycle were analyzed by use of flow cytometry (FCM). The ultrastructural changes were observed by transmission electron microscopy. Autophagy was detected by acridine orange staining. Expression of Bcl-2, Bax, and Beclin 1 proteins was measured by western blot analysis.

Results

The inhibitory effect of ApoG2 on MCF-7 cell proliferation was dose and time-dependent. The maximum effect was observed when cells were incubated for 72 h with 40 μM ApoG2. ApoG2 at 5 μM also inhibited colony formation. FCM assay indicated that ApoG2 induced cell apoptosis and caused cell arrest in the S phase and G2/M phase. Transmission electron microscopic examination and acridine orange staining showed that ApoG2 induced intracellular autolysosome formation. Furthermore, ApoG2 reduced Bcl-2 expression, and enhanced expression of Bax and Beclin 1. Xenografting of MCF-7 cells in mice can also be inhibited by ApoG2.

Conclusion

ApoG2, a novel anti-apoptotic Bcl-2 agent, inhibits proliferation of breast cancer cell line MCF-7 by inducing cell apoptosis and autophagy.     

PTPRZ1通过调控PI3K/Akt通路促进乳腺癌细胞增殖和多西他赛耐药

目的:探讨蛋白酪氨酸磷酸酶受体Z1型(protein tyrosine phosphatase receptor type Z1,PTPRZ1)对人乳腺癌MCF-7细胞多西他赛耐药性的影响及其作用机制。方法:将MCF-7细胞暴露于逐渐增强浓度的多西他赛中建立对多西他赛耐药的乳腺癌细胞（MCF-7/Doc）。采用CCK-8法分别检测MCF-7和MCF-7/Doc细胞对多西他赛的耐药性。qRT-PCR和Western blot检测细胞中PTPRZ1 mRNA及蛋白表达水平。克隆形成实验检测细胞增殖情况，流式实验检测细胞凋亡情况。最后采用Western blot检测PTPRZ1调控乳腺癌化疗敏感性的作用机制。结果:CCK-8实验表明成功构建了乳腺癌多西他赛耐药细胞株MCF-7/Doc，克隆形成实验表明MCF-7/Doc细胞增殖能力显著高于亲本MCF-7细胞（P＜0.05）；MCF-7/Doc细胞中，PTPRZ1 mRNA及蛋白水平均显著上调（P＜0.05）。过表达PTPRZ1能显著增强MCF-7/Doc细胞对多西他赛的耐药性和增殖能力，显著抑制细胞凋亡（P＜0.05）；敲减PTPRZ1能显著降低MCF-7/Doc细胞对多西他赛的耐药性，并能显著诱导细胞凋亡（P＜0.05）。Western blot结果显示，PTPRZ1能够激活PI3K/Akt信号通路。结论:PTPRZ1通过介导PI3K/Akt信号通路促进乳腺癌对多西他赛的耐药性。     

Apogossypolone对乳腺癌MCF-7细胞株放射增敏的体外实验研究

[目的]探讨Apogossypolone(ApoG2)对乳腺癌MCF-7细胞株的放射增敏作用及其作用机制。[方法]①MTT法检测ApoG2单药对MCF-7细胞的抑制率,确立细胞半数抑制浓度(IC50)。②根据MTT结果选取低浓度(相似文献   

Silibinin Enhances Ultraviolet B-Induced Apoptosis in MCF-7 Human Breast Cancer Cells

Purpose

Chemotherapies for breast cancer generally have strong cellular cytotoxicity and severe side effects. Thus, significant emphasis has been placed on combinations of naturally occurring chemopreventive agents. Silibinin is a major bioactive flavonolignan extracted from milk thistle with chemopreventive activity in various organs including the skin, prostate, and breast. However, the mechanism underlying the inhibitory action of silibinin in breast cancer has not been completely elucidated. Therefore, we investigated the effect of silibinin in MCF-7 human breast cancer cells and determined whether silibinin enhances ultraviolet (UV) B-induced apoptosis.

Methods

The effects of silibinin on MCF-7 cell viability were determined using the MTT assay. The effect of silibinin on PARP cleavage, as the hallmark of apoptotic cell death, and p53 protein expression in MCF-7 cells was analyzed using Western blot. The effect of silibinin on UVB-induced apoptosis in MCF-7 cells was analyzed by flow cytometry.

Results

A dose- and time-dependent reduction in viability was observed in MCF-7 cells treated with silibinin. Silibinin strongly induced apoptotic cell death in MCF-7 cells, and induction of apoptosis was associated with increased p53 expression. Moreover, silibinin enhanced UVB-induced apoptosis in MCF-7 cells.

Conclusion

Silibinin induced a loss of cell viability and apoptotic cell death in MCF-7 cells. Furthermore, the combination of silibinin and UVB resulted in an additive effect on apoptosis in MCF-7 cells. These results suggest that silibinin might be an important supplemental agent for treating patients with breast cancer.     

Anti-tumor Effects of IL-1β Induced TRAIL-Expressing hUCMSCs on Embelin Treated Breast Cancer Cell Lines

Background: Human umbilical cord mesenchymal stem cells (hUCMSCs) have high therapeutic value in cancer treatment. We have found that pre-activating hUCMSCs with IL-1β promotes tumor necrosis factor-related apoptosis inducing ligand (TRAIL) expression and facilitates anti-tumor effect. Furthermore, embelin has been found to induce apoptosis of different cancer cell lines by upregulating the expression of TRAIL receptor 1 (DR4) and TRAIL receptor 2 (DR5). This study investigated whether IL-1β induced TRAIL-expressing hUCMSCs, in combination with low-dose embelin, could further induce apoptosis in breast cancer cell lines. Materials and Methods: MTT assay was used to examine the cytotoxicity of embelin in MDA-MB-231 and MCF-7. To detect the interested protein expression in cells, Western blot and cell immunofluorescence were used to double-confirm the observed results. Annexin V/PI apoptosis assay was detected by flow cytometry to analyze the apoptosis rate of embelin treated breast cancer cell lines and the effect of co-culturing with breast cancer cells and hUCMSCs. Results: Using Western blot and immunofluorescence, we found that breast cancer cell lines treated with low-dose embelin (2.5-5 μM) increased the expression of apoptosis-related receptor DR4, DR5 and the cleaved caspase 8, 9 and 3. Moreover, TRAIL expression was enhanced in IL-1β induced hUCMSCs. Combining these observations, we expected that coculturing IL-1β induced hUCMSCs with low dose embelin treated MDA-MB-231 and MCF-7 cells might enhance the apoptosis of breast cancer cells. We confirmed via flow cytometry that coculture of IL-1β induced TRAIL-expressing hUCMSCs and embelin treated MDA-MB-231 and MCF-7 cells enhances the apoptosis rate of these breast cancer cells. Conclusion: We found that embelin upregulated the expression of DR4 and DR5 to increase the TRAIL-mediated apoptosis in breast cancer cell lines. Low dose embelin treated breast cancer cell lines in combination with IL-1β induced TRAIL-expressing hUCMSCs may become a potential anti-tumor therapy.     

甲异靛对人乳腺癌MCF-7细胞增殖和凋亡影响的实验研究

目的:研究甲异靛对人乳腺癌MCF-7细胞增殖抑制和诱导凋亡作用。方法:采用MTT法检测甲异靛对MCF-7乳腺癌细胞的增殖抑制;流式细胞仪测定细胞凋亡率;光学显微镜观察细胞形态的变化;westernblot法测定caspase-3、PARP及bcl-2表达。结果:甲异靛能明显抑制MCF-7乳腺癌细胞增殖。甲异靛诱导MCF-7细胞凋亡,呈现典型细胞凋亡的形态变化,并呈时间和剂量依赖性,凋亡率最高可达(68.40±4.87)%,在细胞凋亡过程中出现PARP分子断裂和bcl-2下调,未检测到caspase-3。结论:甲异靛能诱导MCF-7乳腺癌细胞凋亡抑制细胞增殖,其发生机制可能与下调bcl-2有关。     

Roles of p53 and Caspases in Induction of Apoptosis in MCF-7 Breast Cancer Cells Treated with a Methanolic Extract of Nigella Sativa Seeds

Background: Nigella Sativa (NS) is an herb from the Ranunculaceae family that exhibits numerous medicinalproperties and has been used as important constituent of many complementary and alternative medicines (CAMs).The ability of NS to kill cancer cells such as PC3, HeLa and hepatoma cells is well established. However, ourunderstanding of the mode of death caused by NS remains nebulous. The objective of this study was to gainfurther insight into the mode and mechanism of death caused by NS in breast cancer MCF-7 cells. Materialsand Methods: Human breast cancer cells (MCF-7) were treated with a methanolic extract of NS, and a dose- andtime-dependent study was performed. The IC50 was calculated using a Cell Titer Blue® viability assay assay, andevidence for DNA fragmentation was obtained by fluorescence microscopy TUNEL assay. Gene expression wasalso profiled for a number of apoptosis-related genes (Caspase-3, -8, -9 and p53 genes) through qPCR. Results:The IC50 of MCF-7 cells was 62.8μL/mL. When MCF-7 cells were exposed to 50 μL/mL and 100 μL/mL NS for24h, 48h and 72h, microscopic examination (TUNEL assay) revealed a dose- and time-dependent increase inapoptosis. Similarly, the expression of the Caspase-3, -8, -9 and p53 genes increased significantly according to thedose and time. Conclusions: NS induced apoptosis in MCF-7 cells through both the p53 and caspase pathways.NS could potentially represent an alternative source of medicine for breast cancer therapy.     

靶向survivin的siRNA抑制乳腺癌MCF-7细胞增殖并诱导其凋亡

目的 观察靶向survivin的siRNA对乳腺癌细胞增殖和凋亡的影响。方法构建靶向survivin的siRNA真核表达载体,采用Lipofectamine^TM2000转染乳腺癌细胞MCF-7,采用半定量RTPCR、免疫组化技术检测转染前后MCF-7细胞survivin基因表达的变化;采用MTT法检测对MCF-7细胞增殖的抑制作用;采用TUNEL法检测诱导MCF-7细胞凋亡的作用。结果靶向survivin的序列特异性siRNA可以高效抑制MCF-7细胞survivin基因的表达,在mRNA水平其表达抑制率为64．9％;在蛋白质水平其表达抑制率为79．7％;转染靶向survivin的siRNA真核表达载体可以显著抑制MCF-7细胞的增殖,细胞重新接种24、48h后,其增殖抑制率分别为31．6％和33．0％;转染后24h可以诱导12．9％的细胞凋亡。结论利用RNA干扰技术阻断survivin基因的表达可以显著抑制MCF-7细胞的增殖,并在一定程度上诱导其自发凋亡,靶向survivin的RNA干扰技术在乳腺癌的基因治疗中具有一定的价值。     

Daidzein Induces Intrinsic Pathway of Apoptosis along with ER α/β Ratio Alteration and ROS Production

Background: Low risk of breast cancer is observed among females consuming a moderate quantity of soy throughout their life. The present study was conducted to evaluate the anticancer potential of Daidzein, one of the major Isoflavones in soy using Human breast cancer cells MCF-7. Methods: MCF-7 were subjected to various doses of Daidzein treatment to determine the IC50 value. Onset of apoptosis was ascertained by AnnexinV assay and caspase 3/7 activity post treatment. Expression of pro-apoptotic protein Bax and anti-apoptotic protein Bcl2 was also assessed to further confirm apoptotic mode of cell death. ROS production post treatment with Daidzein was assessed to ascertain the apoptosis via intrinsic pathway. Expression of ER α and ER β was evaluated by western blot analysis. Results: Human breast cancer cells MCF-7 were found to be sensitive to Daidzein treatment, with an IC50 value of 50µM. Increased percentage of treated cells stained with Annexin V confirmed apoptosis mediated cell death. Activity of Caspase 3/7 activity was found to be 1.4-fold higher in Daidzein treated cells than control cells, confirming apoptosis. Daidzein caused over expression of Bax and down-regulated expression of Bcl2. There has been an outburst of ROS in Daidzein treated cells indicating that Daidzein induces apoptosis via intrinsic pathway. A decrease in the expression of ER α and increase in levels of ER β has been observed which are conducive indicator of apoptosis. Conclusions: In conclusion, the present study suggests that Daidzein induces apoptosis in MCF-7 cells by mitochondrial pathway along with lowering the ratio of ER α/β and an outburst of Reactive Oxygen Species(ROS).     

PXD101对人乳腺癌细胞MCF-7增殖及凋亡影响的机制探讨

  目的  探讨组蛋白去乙酰化酶抑制剂PXD101对人乳腺癌细胞MCF-7增殖、细胞周期及凋亡的影响及分子机制研究。  方法  应用不同浓度PXD101处理培养的乳腺癌细胞株MCF-7, 通过赛唑蓝比色(MTT)法和平板克隆形成实验检测药物对细胞增殖的影响; HoechSt33342荧光染色法观察细胞形态变化; 流式细胞仪PI染色法检测细胞周期变化以及AnnexinV-FITC/PI双染法检测细胞凋亡情况; Westen blot检测p21、CyclinB1、PARP、Bcl-2以及Bax的蛋白表达。  结果  PXD101以剂量时间依赖性抑制MCF-7细胞的增殖; 荧光显微镜观察发现细胞核碎裂, 出现凋亡小体; 0、0.1、1、10μmol/L PXD101作用24 h后, G₂/M期细胞比例增加, 分别为(12.66±1.55)%、(20.63±1.32)%、(23.20±1.82)%、(32.19±2.37)%(P < 0.05), 凋亡细胞也增加(P < 0.05);p21表达增多, CyclinBl表达减少, PARP剪切明显增加, Bcl-2表达减少, Bax表达增加。  结论  PXD101在体外条件下能够明显抑制乳腺癌MCF-7细胞的增殖, 诱导细胞周期阻滞及凋亡, 并呈剂量依赖性。      

红松松塔提取物多聚苯丙素-多糖复合物诱导人乳腺癌MCF-7细胞凋亡

目的 研究红松松塔提取物多聚苯丙素-多糖复合物(Polyphenylpropenoid-polysaccharide complex,PPC)诱导人乳腺癌MCF-7细胞凋亡的机制。方法 用体外培养的MCF-7细胞与不同浓度PPC作用不同时间,应用MTT法、荧光染色法、凋亡检测试剂盒、DNA凝胶电泳及Western blot检测PPC对MCF-7细胞增殖的影响和诱导凋亡的作用。结果 PPC可诱导MCF-7细胞发生凋亡。细胞凋亡时Caspase-3和Caspase-9的酶活力升高,Caspase-3前体酶蛋白表达下降;Caspase-3抑制剂(z-DEVE-fmk)可部分抑制PPC诱导的细胞凋亡,并抑制Caspase-3前体酶的活化。结论 PPC通过激活Caspase家族诱导MCF-7细胞凋亡。     

TRIP-Br1 oncoprotein inhibits autophagy,apoptosis, and necroptosis under nutrient/serum-deprived condition

TRIP-Br1 oncogenic protein has been shown to have multiple biological functions in cells. In this study, we demonstrate that TRIP-Br1 functions as an oncoprotein by inhibiting autophagy, apoptosis, and necroptosis of cancer cells and eventually helping them to survive under the nutrient/serum starved condition. TRIP-Br1 expression level was significantly increased in conditions with low levels of nutrients. Nutrient depleted conditions were induced by culturing cancer cells until they were overcrowded with high cell density or in media deprived of glucose, amino acids, or serum. Among them, serum starvation significantly enhanced the expression of TRIP-Br1 only in all tested breast cancer cell lines (MCF7, MDA-MB-231, T47D, MDA-MB-435, Hs578D, BT549, and MDA-MB-435) but not in the three normal cell lines (MCF10A, HfCH8, and NIH3T3). As compared with the control cells, the introduction of TRIP-Br1 silencing siRNA into MCF7 and MDA-MB-231 cells accelerated cell death by inducing apoptosis and necroptosis. In this process, TRIP-Br1 confers resistance to serum starvation-induced cell deaths by stabilizing the XIAP protein and inhibiting cellular ROS production. Moreover, our data also show that the intracellular increase of TRIP-Br1 protein resulting from serum starvation seems to occur in part through the blockage of PI3K/AKT signaling pathway.     

乳腺癌中COX-2表达及其抑制剂塞来昔布对乳腺癌细胞系增生和凋亡的影响

目的为进一步观察COX-2对乳腺癌的作用,我们检测了乳腺癌组织、乳腺癌细胞株MCF-7和B37中COX-2的表达,并观察选择性COX-2抑制剂塞来昔布对乳腺癌细胞株生长和凋亡的影响。方法应用免疫组织化学染色的方法检测132例乳腺癌组织标本中COX-2蛋白的表达;应用免疫细胞化学染色、原位杂交、逆转录多聚酶联反应（RT-PCR）的方法,分别检测COX-2蛋白和mRNA在乳腺癌细胞株MCF-7、B37中的表达;采用MTT法、AO/EB双荧光染色法和流式细胞术,研究塞来昔布对乳腺癌细胞增殖和凋亡的影响。结果52.3%(69/132)的乳腺癌组织标本表达COX-2蛋白;在乳腺癌细胞株MCF-7和B37中均有COX-2的表达,25μmol/L塞来昔布作用72h后,COX-2表达明显减少;25、50、100μmol/L的塞来昔布与MCF-7细胞作用72h,生长抑制率分别为36.3%、57.7%、74.5%。100μmol/L塞来昔布作用72h后,MCF-7细胞凋亡率为38.5％。结论乳腺癌组织和乳腺癌细胞株MCF-7、B37中存在COX-2的表达;塞来昔布可抑制乳腺癌细胞增殖,并促进细胞凋亡,塞来昔布可能作为新的药物治疗乳腺癌。