EGFR antisense RNA blocks expression of the epidermal growth factor receptor and partially reverse the malignant phenotype of human breast cancer MDA-MB-231 cells

The effects of human EGFR to the malignant phenotype of human breast cancer cell line MDA-MB-231 were investigated experimentally. A retroviral vector containing a 5'1350bp fragment of the human EGFR cDNA in the antisense orientation was transfected into targeted cells by lipofectamine. The effects on cell proliferation, cell cycle and adherent ability to extracellular matrix (ECM) components were studied after the expression of antisense transcripts to EGFR 5'1350bp fragment in target cells. In vitro studies showed that the growth ability of the transfected cells was partialy inhibited in comparison to parental cells and to cells transfected with the plasmid containing the neomycin resistance gene only. It was found that EGF (10ng/ml) had an augmenation effect on the growth of transfected MDA-AS10 cells but not MDA-MB-231 cells.Flow cytometric analysis showed that the cell cycle of the transfected cells was abnormal with a decrease of cells in G2/M and S phases and an increase of cells in G1 phase,indicating a blockage in phase G1. Immunofluorescence of EGFR expression in transfectants stained with an antiEGFR antibody was decreased and their growth in soft agarose was also severely impaired. The transfected cells showed less adherence to laminin (LN) and fibronectin (FN). In short, EGFR antisense RNA decreases the expression of EGFR on MDA-MB-231 cells and partially reverses their malignant phenotype as well.Effects of antisense EGFR on human breast cancer MDA-MB-231 cells

Methanolic extract of Abrus precatorius promotes breast cancer MDA-MB-231 cell death by inducing cell cycle arrest at G0/G1 and upregulating Bax

Objective:To determine the anti-proliferative activity of Abrus precatorius(A.precatorius)leaf extracts and their effect on cell death.Methods:A.precatorius leaves were extracted successively with hexane,ethyl acetate and methanol by Soxhlet extraction.Aqueous extract was prepared by decoction at 50 ℃.Extracts of A.precatorius leaves were used to treat selected cancer and normal cell lines for72 h.Furthermore,3-(4,5-dimethyl thiazol-2-yl)2,5-diphenyl tetrazolium bromide assay was performed to determine cell viability.Analysis of cell cycle arrest,apoptosis assay and apoptosis protein expressions were determined by flow cytometry.Results:Methanolic extract of A.precatorius leaves showed the lowest IC50 on MDA-MB-231 cells at(26.40±5.40)μg/mL.Flow cytometry analysis revealed that cell arrest occurred at G0/G1 phase and the apoptosis assay showed the occurrence of early apoptosis at 48 h in MDAMB-231 cells treated with methanolic extract of A.precatorius leaves.Methanolic extract of A.precatorius leaves induced apoptosis by upregulation of Bax,p53 and caspase-3 and downregulation of Bcl-2.Conclusions:Methanolic extract of A precatorius leaves promotes MDA-MB-231 cell death by inducing cell cycle arrest and apoptosis possibly via the mitochondrial-related pathway.

Effect of amlodipine on apoptosis of human breast carcinoma MDA-MB-231 cells

Objective： To elucidate the effects of amlodipine on the proliferation and apoptosis of human breast carcinoma MDA-MB-231 cells. Methods： Light microscopy was used to determine the effects of amlodipine on cell morphology; Flow cytometry was used to quantitate cells undergoing apoptosis; the expression of a cell cycle-related protein, proliferating cell nuclear antigen （PCNA） and an antiapoptosis protein, Bcl-2 were assessed by immunocytochemistry. Results： Amlodipine concentration of 8.25umol/L （1/2 of ICs0） affected the morphology, decreased the expression of PCNA and Bcl-2 and induced apoptosis of human breast carcinoma MDA-MB-231 cells. Conclusion： The effect of amlodipine on the antiproliferation of human breast carcinoma MDA-MB-231 cells is related to inducement of apoptosis, and the decrease of the expression of Bcl-2 and PCNA may be the possible mechanism for proliferation inhibitory and inducement of apoptosis.

Down-Regulation of Notchl and NF-κB by Curcumin in Breast Cancer Cells MDA-MB-231

Objective： To test whether the down-regulation of Notchl gene expression by curcumin could inhibit cell growth and induce apoptosis, which may be associated mechanistically with the down-regulation of NF-κB in breast cancer cells. Methods： Breast cancer cell lines MDA-MB-231 were cultured in vitro and treated with different dosages of curcumin （0, 1.25, 5.0, 20.0μmol/L） for dose-dependent assay and different time （0, 24, 48, 72 h） at the dosage of 5.0μmol/L for time course assay. The changes of the mRNA and protein expression of Notchl and NF-κB were measured by RT-PCR and Western Blot, and MTT assay was used to measure the change of proliferation. Results： The mRNA and protein levels of Notchl and NF-κB were decreased significantly in human breast cancer cell line with the increase of dosage of curcumin（P〈0.05）, and with the extension of time course（P〈0.05）. These changes suggested a dose- and time-dependent manner. The proliferation rate of cells also was significantly inhibited（P〈0.05）. Conclusion： The current results show that the Notch-1 signaling pathway is associated mechanistically with NF-κB activity during curcumin-induced cell growth inhibition and apoptosis of breast cancer cells. These results suggest that the down-regulation of Notch signaling by curcumin may be a novel strategy for the treatment of patients with breast cancer.

Investigation of Methylation Profiles of TP53, Caspase 9, Caspase 8, Caspase 3 Genes Treated with DNA Methyl Transferase Inhibitor (DNMTi) Zebularine (ZEB) and Caffeic Acid Phenethyl Ester (CAPE) on MCF-7 and MDA-MB-231 Breast Cancer Cell Lines

Purpose: MCF-7 (ER+, WTP53) and MDA-MB-231 (ER Met, Mutant P53) Caffeic Acid Phenethyl Ester (CAPE) and DNA Methyl Transferase Inhibitor (DNMTi) in breast cancer cell lines of Zebularine (ZEB) single and combined application of TP53, caspase-9, caspase 8 and caspase-3 genes as a result of the use of single and combined drug methylation profiles are aimed to be evaluated by specific PCR method. Material-Metods: In the MCF-7 and MDA-MB-231 breast cancer cell lines, MTT test and survival analysis were performed as a result of single and combined application of CAPE and Zebularine and Methylation Specific PCR was performed to examine the methylation of caspase-3, caspase-8, caspase-9 and TP53 genes. Results: According to the results of 24-hour drug administration, the IC50 for the MCF-7 cell line was determined as 200 μM, for CAPE 40 μM and for the combined values of 50 μM ZEB + 5 μM CAPE. The effects of caspase-3, caspase-8, caspase-9 and TP53 genes on the methylation level of ZEB, CAPE and ZEB + CAPE drug combination were determined by using bisulfite modified DNAs in MCF-7 and MDA-MB-231 cell lines. Discussion: In the MCF-7 cell line, the 120 μM ZEB viability rate was 51%, and the viability of 80 μM ZEB MDA-MB-231 breast cancer cells decreased by 59.7%. After 20 μM CAPE, viability in MCF-7 cells decreased by 31% in 120 μM CAPE and MDA-MB-231 cells decreased by 41%. The viability with 40 μM CAPE decreased by 19% in MDA-MB-231 cells. It was found that 20 μM CAPE concentration was associated with TP53 methylation in MCF-7 cell lines. The 80 μM ZEB concentration was found to be closely related to the unmethylated status of the TP53 gene. These results obtained with 50 μM ZEB + 5 μM CAPE application were found to be related to the methylated-unmetylated status of the TP53 gene in half (50%). For the caspase-9 gene of MDA-MB-231 cells, 80 μM ZEB concentration was found to be associated with unmetylated status. The effective use of drugs with low concentrations of the drug dose provides a more appropriate approach in terms of treatment.

不同浓度吗啡复合罗哌卡因对乳腺癌MDA-MB-231细胞增殖、迁移、侵袭和细胞周期的作用影响

目的 观察不同浓度的吗啡复合罗哌卡因对乳腺癌MDA-MB-231细胞增殖、转移侵袭和细胞周期的影响。方法 人乳腺癌细胞MDA-MB-231细胞接种于培养板24h,随机分为8组:对照组(C组)、罗哌卡因400μg/ml组(R组)、吗啡3μg/ml组(LM组)、吗啡30μg/ml组(MM组)、吗啡300μg/ml组(HM组)、罗哌卡因400μg/ml组+吗啡3μg/ml组(R+LM组)、罗哌卡因400μg/ml+吗啡30μg/ml组(R+MM组)和罗哌卡因400μg/ml+吗啡300μg/ml组(R+HM组)。处理乳腺癌细胞MDA-MB-231细胞24h后,检测其增殖能力、迁移能力、侵袭能力和细胞周期。结果 人乳腺癌细胞MDA-MB-231细胞的增殖抑制情况:单独应用吗啡时,LM组、MM组、HM组均对人乳腺癌细胞MDA-MB-231细胞的增殖具有抑制作用(P<0.05),并且抑制率随着吗啡浓度的升高而依次增加。单独应用罗哌卡因时对人乳腺癌细胞MDA-MB-231细胞的增殖具有抑制作用(P<0.05)。吗啡与罗哌卡因联合应用时,高浓度吗啡组与罗哌卡因具有协同作用。人乳腺癌细胞MDA-MB-231细胞的迁移情况:单独应用吗啡时,LM组、MM组、HM组均能够抑制细胞迁移率(P<0.05),迁移率随着吗啡浓度的升高而依次降低。单独应用罗哌卡因能够抑制细胞迁移率(P<0.05)。吗啡与罗哌卡因联合应用时,低浓度和中浓度吗啡组与罗哌卡因具有协同作用(P<0.05)。人乳腺癌细胞MDA-MB-231细胞的侵袭情况:单独应用吗啡时,MM组、HM组均能够抑制细胞侵袭能力(P<0.05),并且侵袭能力随着吗啡浓度的升高而依次降低,单独应用罗哌卡因时能够抑制细胞的侵袭能力(P<0.05)。吗啡与罗哌卡因联合应用时,中、高浓度组吗啡和罗哌卡因具有协同作用。人乳腺癌细胞MDA-MB-231细胞的细胞周期情况:单独应用高浓度吗啡,能够抑制细胞进入G2/M期(P<0.05)。单独应用罗哌卡因,能够抑制细胞进入G2/M期(P<0.05),低浓度吗啡与罗哌卡因联合应用对于将细胞抑制在G0/G1期和S期具有协同作用(P<0.05)。结论 吗啡复合罗哌卡因能够抑制乳腺癌MDA-MB-231细胞的增殖、迁移和侵袭,具有联合作用并呈剂量依赖性。

Exploring the molecular mechanism of Epimedium brevicornu Maxim.in treating breast cancer via network pharmacology and in vitro experiments Author links open overlay panel

Objective To evaluate the therapeutic effects of Epimedium brevicornu Maxim.(EBM,Yin Yang Huo)on breast cancer using network pharmacology and in vitro validation.It also aimed to explore the novel targets and mechanisms of EBM in the treatment of breast cancer to facilitate the discovery of new drugs and their clinical application.Methods Network pharmacology was used to identify and screen the components and targets of EBM for breast cancer treatment.Molecular docking was further screened the effective components and targets of EBM.Wound-healing assays and flow cytometry analysis were used to detect the ability of two compounds to intervene in the migration and apoptosis of MDA-MB-231 cells,and their mechanism of action was further explored using western blotting experiments.Results EBM contained 19 active components.Among them wereβ-anhydroicaritin(Anhy)and isoliquiritigenin(Iso),which were selected for in vitro experiments.Treatment resulted in a dose-dependent suppression of MDA-MB-231 cell viability,with an IC50 of 23.73μmol/L for Iso and 21.28μmol/L for Anhy.In the wound healing assay,cells in Anhy and Iso groups exhibited considerable inhibition of migration at 48 h.In flow cytometry analysis,treatment with Iso(20μmol/L)for 96 h resulted in significantly higher levels of both early and late apoptosis in the Iso group than that in the control group(P=.004 and P=.014,respectively).Additionally,both Iso(20μmol/L)and Anhy(10 and 20μmol/L)induced cell necrosis at 96 h.Western blotting revealed that Anhy and Iso increased the expression of Bax and TBK1/NAK.Conclusion These findings suggested that Anhy and Iso,the two components of EBM,inhibit MDA-MB-231 cell proliferation and migration of and induce their apoptosis,providing substantial support for future studies on breast cancer.

基于ERK/NF-κB通路探讨苦杏仁苷对乳腺癌MDA-MB-231细胞增殖、侵袭、迁移的影响

目的探讨苦杏仁苷对乳腺癌MDA-MB-231细胞增殖、侵袭、迁移及细胞外信号调节激酶(ERK)/核因子(NF)-κB通路的影响。方法将乳腺癌MDA-MB-231细胞随机分成对照组、紫杉醇组(10μg/ml)、苦杏仁苷低剂量组(20μg/ml)、苦杏仁苷高剂量组(40μg/ml);以上各组每孔设6个平行样,培养72 h。实验结束后,噻唑蓝(MTT)法测定乳腺癌MDA-MB-231细胞增殖水平,Transwell小室测定乳腺癌MDA-MB-231细胞侵袭迁移水平,实时荧光定量聚合酶链反应(PCR)及Western印迹法测定乳腺癌MDA-MB-231细胞ERK、NF-κB mRNA和蛋白表达水平。结果与对照组比较,紫杉醇组、苦杏仁苷低、高剂量组光密度(OD)值、细胞存活率、穿膜数、ERK、NF-κB mRNA和蛋白表达水平显著降低(P<0.05);与紫杉醇组比较,苦杏仁苷低剂量组上述指标显著升高(P<0.05),苦杏仁苷高剂量组上述指标无显著差异(P>0.05);与苦杏仁苷低剂量组比较,苦杏仁苷高剂量组上述指标显著降低(P<0.05)。结论苦杏仁苷能明显抑制乳腺癌MDA-MB-231细胞增殖、侵袭、迁移,其机制可能与苦杏仁苷抑制ERK、NF-κB mRNA和蛋白表达进而抑制ERK/NF-κB通路的激活有关。

Piperine suppresses growth and migration of human breast cancer cells through attenuation of Rac1 expression

Objective:To investigate the effect of piperine on human breast cancer cells.Methods:The effect of piperine on proliferation and migration of human breast cancer cells,MCF-7 and MDA-MB-231,was investigated using colony formation assays,wound healing assays,Matrigel migration assays,flow cytometry,RT-qPCR,and Western blotting assays.Results:Piperine inhibited the growth of MCF-7 and MDA-MB-231 cells and suppressed colony formation.Cell reduction at the G_(0)/G_(1) phase and cell arrest at the G_(2)/M phase were observed in breast cancer cells.However,the significant effect was only demonstrated in MDA-MB-231 cells.Moreover,cancer cell migration was suppressed by piperine at low concentration.RT-qPCR and Western blotting assays showed that piperine downregulated Rac1 gene and protein expression.Conclusions:Piperine could inhibit growth and migration of breast cancer cells by reducing Rac1 gene and protein expression.

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.

Loss of the vitamin D receptor in human breast and prostate cancers strongly induces cell apoptosis through downregulation of Wnt/β-catenin signaling

Vitamin D co-regulates cell proliferation, differentiation and apoptosis in numerous tissues, including cancers. The known anti-proliferative and pro-apoptotic actions of the active metabolite of vitamin D, 1,25-dihydroxy-vitamin D [1,25（OH）2D] are mediated through binding to the vitamin D receptor （VDR）. Here, we report on the unexpected finding that stable knockdown of VDR expression in the human breast and prostate cancer cell lines, MDA-MB-231 and PC3, strongly induces cell apoptosis and inhibits cell proliferation in vitro. Implantation of these VDR knockdown cells into the mammary fat pad （MDA-MB-231）, subcutaneously （PC3） or intra-tibially （both cell lines） in immune-incompetent nude mice resulted in reduced tumor growth associated with increased apoptosis and reduced cell proliferation compared with controls. These growth-retarding effects of VDR knockdown occur in the presence and absence of vitamin D and are independent of whether cells were grown in bone or soft tissues. Transcriptome analysis of VDR knockdown and non-target control cell lines demonstrated that loss of the VDR was associated with significant attenuation in the Wnt/0-catenin signaling pathway. In particular, cytoplasmic and nuclear β-catenin protein levels were reduced with a corresponding downregulation of downstream genes such as Axin2, Cyclin D1, interleukin-6 （IL-6）, and IL-8. Stabilization of 0-catenin using the GSK-3β inhibitor BIO partly reversed the growth-retarding effects of VDR knockdown. Our results indicate that the unliganded VDR possesses hitherto unknown functions to promote breast and prostate cancer growth, which appear to be operational not only within but also outside the bone environment. These novel functions contrast with the known anti-proliferative nuclear actions of the liganded VDR and may represent targets for new diagnostic and therapeutic approaches in breast and prostate cancer.

Effects of Estradiol and Tamoxifen on Proliferation of Human Breast Cancer Cells and Human Endometrial Cells

The effects of estradiol and tamoxifen on the proliferation of estrogen receptor positive cells and the relationship between the tamoxifen tolerance and cell origin were investigated The tissues of human endometrium and breast cancer were randomly selected following dissection for primary cell culture After the breast cancer cells and endometrial cells were treated with 1×10 -8 mol/L estradiol and/or 1 ×10 -6 tamoxifen, 3H-labelled thymine nucleotide was used to trace the kinetics of cell proliferation There was no significant difference in the inhibition on the human endometrial cells between tamoxifen-treated group (6 3%) and control group (6 4%), but tamoxifen could significantly inhibit the proliferation of the human breast cancer cells (45 84%) as compared with control group (52 72%) Moreover, tamoxifen could significantly stimulate the proliferation of tamoxifen resistant breast cancer cells (9 64%) as compared with control group (6 32%) Estradiol could significantly stimulate the proliferation of all the three kinds of cells as compared with control group The combined use of estradiol and tamoxifen could inhibit the proliferation of the endometrial cells and breast cancer cells as compared with estradiol used alone, but on the tamoxifen resistant breast cancer cells, they could more significantly stimulate the proliferation than E2 It was concluded that E2 could stimulate the proliferation of these three kinds of cells However, the inhibitive effects of tamoxifen on the proliferation of these cells were dependent on the estradiol

Effects of bisphenol compounds on the growth and epithelial mesenchymal transition of MCF-7 CV human breast cancer cells

Bisphenol-A（BPA） has been considered as an endocrine disrupting chemical（EDC） because it can exert estrogenic properties.For bisphenol-S（BPS） and bisphenol-F（BPF） that are BPA analogs and substitutes,their risk to estrogendependent cancer has been reported rarely compared with the numerous cases of BPA.In this study,we examined whether BPA,BPS,and BPF can lead to the proliferation,migration,and epithelial mesenchymal transition（EMT） of MCF-7 clonal variant（MCF-7 CV） breast cancer cells expressing estrogen receptors（ERs）.In a cell viability assay,BPA,BPS,and BPF significantly increased proliferation of MCF-7 CV cells compared to control（DMSO） as did17β-estradiol（E2）.In Western blotting assay,BPA,BPS,and BPF enhanced the protein expression of cell cycle progression genes such as cyclin D1 and E1.In addition,MCF-7 CV cells lost cell to cell contacts and acquired fibroblast-like morphology by the treatment of BPA,BPS,or BPF for 24 hours.In cell migration assay,BPA,BPS,and BPF accelerated the migration capability of MCF-7 CV cells as did E2.In relation with the EMT process,BPA,BPS,and BPF increased the protein expression of N-cadherin,while they decreased the protein expression of Ecadherin.When BPA,BPS,and BPF were co-treated with ICI 182,780,an ER antagonist,proliferation effects were reversed,the expression of cyclin D1 and cyclin E1 was downregulated,and the altered cell migration and expression of N-cadherin and E-cadherin by BPA,BPS,and BPF were restored to the control level.Thus,these results imply that BPS and BPF also have the risk of breast cancer progression as much as BPA in the induction of proliferation and migration of MCF-7 CV cells by regulating the protein expression of cell cycle-related genes and EMT markers via the ER-dependent pathway.

Effect of Guizhi Fuling capsule and its extracts on human breast cancer cells proliferation

OBJECTIVE To evaluate the effect of Guizhi Fuling Capsule active pharmaceutical ingredient(API)and its fractions on human breast cancer cells proliferation by high-throughput screening assay.METHODS The crude fractions were obtained from the extraction and elution of the API of Guizhi Fuling Capsule,and 929 standard fractions were obtained by the optimal separation conditions.Sulforhodamine B(SRB)method was used to evaluate the effects of the Guizhi Fuling capsule API and929 kinds of fractions on the proliferation of human breast cancer cells MCF-7 and MDA-MB-231.RESULTS The Guizhi Fuling capsule API had a strong ability to inhibit the proliferation of MCF-7 cells at high concentration and the ability to inhibit MDA-MB-231 cells' proliferate at low concentration following 72 h treatment;some samples of 929 fractions(5μg·mL^(-1))was found to have a breast cancer cell growth inhibition rate above 50%,without toxicity on HUVECs proliferation.CONCLUSION The API of Guizhi Fuling capsule had significant cytotoxicity effects on these two human breast cancer cells,with significant concentration-and time-dependent manner.

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.

Investigating the effects of Pentoxifylline on human breast cancer cells using Raman spectroscopy

Breast cancer is one of the leading causes of cancer-related deaths in a global scenario.In the present study,biochemical changes exerted upon Pentoxifylline(PTX)treatment had been ap-praised in human breast cancer cells using Raman spectrosecopy.There are no clinically approved methods to monitor such therapeutic responses available.The spectral profiling is suggestive of changes in DNA,protein and lipid contents showing a linear relationship with drug dosage.Further,multivariate analysis using principal component based linear-discriminant-analysis(PC-LDA)was employed for dlassifying the control and the PTX treated groups.These findings support the feasibility of Raman spectroscopy as an alternate/adjunct label-free,objective method for monitoring drug-induced modifications against breast cancer cells.

QCM Detection of Adhesion, Spreading and Proliferation of Human Breast Cancer Cells (MCF-7) on a Gold Surface

The quartz crystal microbalance （QCM） was used to monitor the one-day incubation of human breast cancer cells （MCF-7） on the gold electrode. In combination with an optical microscope simulation experiment, the cell-population pictures at various stages, the QCM responses to the cells＇ adhesion, spreading and proliferation on the electrode surface were discussed. The △f0 and △R1 responses were found mainly from mixed effects of viscodensity and surface stress, and in proportion to the cell coverage, rather than to the number of cells at the electrode. The significant fore-and-aft changes in cyclic voltammetry and electrochemical impedance spectroscopy of the ferri-ferrocyanide redox couple also proved that the cells were adhesion to the gold surface.

Inhibition of γ-synuclein (SNCG) expression in breast cancer MDA-MB231 cell line

Objective:The aim of the study was to evaluate the inhibition of different chemotherapy drugs on γ-synuclein (SNCG) positive expression of breast cancer cell line MDA-MB231,and the effects on cell cycle and apoptosis,and to explore the related mechanism as well.Methods:We treated the breast cancer cell line MDA-MB231 for the inhibition of SNCG with chemotherapy drugs such as irinotecan,nedaplatin and 5-fluorouracil using RT-PCR and immunohistochemistry,and adopted flow cytometry to detect cell cycle distribution and apoptosis.Results:At the transcription and translation levels,the SNCG expression level in nedaplatin group and 5-fluorouracil group was lower than that of other groups and there was statistically significance (P < 0.01) compared with the control group,while there was not statistically significant between irinotecan group and the control group.After drugs action,cell cycle and distribution in each experiment group changed obviously,where the cells in G0G1 phase increased,especially the cells in the nedaplatin group and 5-fluorouracil group changed most significantly,as well as the obvious change in the cells of nedaplatin group and 5-fluorouracil group in the apoptosis period.Conclusion:There was a stronger inhibition of SNCG expression in nedaplatin and 5-fluorouracil groups,and can cause significant cell cycle and apoptosis changes.It may also be concluded that nedaplatin and 5-fluorouracil could make effects by the mechanisms of inhibiting cancer cell proliferation and inducing cell apoptosis.

咪达唑仑诱导乳腺癌细胞MDA-MB-231凋亡并抑制细胞恶性增殖、干样特性及AKT磷酸化

目的 探讨咪达唑仑对乳腺癌细胞MDA-MB-231增殖、凋亡、干样特性及蛋白激酶B(AKT)的影响。方法 CCK8法检测不用浓度咪达唑仑对乳腺癌细胞MDA-MB-231活力的影响,筛选合适的剂量;克隆形成检测细胞增殖;流式检测细胞凋亡;Western印迹检测凋亡相关蛋白的表达[半胱天冬酶(Caspase)-3、Caspase-9];显微观察干细胞成球;Western印迹检测干细胞标志物八聚体结合转录因子(OCT)4、性别决定区γ框蛋白(SOX)2和AKT的磷酸化;免疫荧光检测AKT的核转位。结果 与对照组相比,75μmol/L咪达唑仑组对MDA-MB-231细胞活力的影响无明显差异,随浓度的增加,细胞活力明显减少。CCK8实验结果,筛选4个剂量组(0、75、150、300μmol/L),进行后续实验;与对照组相比,除75μmol/L剂量组差异无统计学意义外,150、300μmol/L剂量组,细胞凋亡率、凋亡蛋白表达水平明显升高(P<0.05);克隆细胞形成率、干细胞成球数量及直径、OCT4及SOX2表达量、AKT的磷酸化表达均明显降低。结论 咪达唑仑诱导乳腺癌细胞MDA-MB-231凋亡并抑制肿瘤细胞恶性增殖、干样特性,其机制可能是通过下调SOX2、OCT4表达,减少癌细胞内AKT信号通路的调节,从而抑制AKT磷酸化水平及AKT核转位。缓解乳腺癌的发生发展。

Human adipose tissue-derived stem cells in breast reconstruction following surgery for cancer: A controversial issue

Breast cancer is the most common cancer in women. Patients, in particular young women, after surgical removal of the tumor have a poorer quality of life and psychological problems. Plastic surgery procedures for breast reconstruction, including autologous fat grafting, concur to reduce cosmetic and psychological problems. The maintenance of the transplanted fat is partially due to the presence of resident adipose derived-stem cells (ASCs). The latter can be isolated by digestion and centrifugation from the stromal vascular fraction (SVF) of subcutaneous adipose tissue. Intraoperatory SVF/ASC enrichment has been proposed to stabilize and optimalize autologous fat engraftment for breast reconstructive surgery after mastectomy, but the safety of these procedures is still uncertain. Although the literature offers contrasting opinions concerning the effects of ASCs on cancer growth according to the tumor type, at the present time ASC implementation for regenerative medicine therapies should be carefully considered in patients previously treated for breast cancer. At the present, reconstructive therapy utilizing ASC-enriched fat grafting should be postponed until there is no evidence of active disease.