UBE2T mediates the stemness properties of breast cancer cells through the mTOR signaling pathway

Objectives:This study aimed to reveal the role and possible mechanism of the ubiquitin-conjugating enzyme 2T(UBE2T)in the biological activities of breast cancer stem cells(BCSCs).Methods:The specific protein and gene expression were quantified by Western blotting and quantitative real-time polymerase chain reaction,the proportion of BCSCs was examined by flow cytometry,and the self-renewal and proliferation of BCSCs were verified by serial sphere formation and soft agar.Results:Increasing expression of UBE2T was drastically found in breast cancer than that in adjacent tissues.Furthermore,UBE2T overexpression significantly increased the proportion of BCSCs in breast cancer cells and promoted their self-renewal and proliferation.Silent UBE2T exhibited the opposite functions.UBE2T increased the levels of the mammalian target of rapamycin and the phosphorylated mammalian target of rapamycin.Mammalian target of rapamycin(mTOR)inhibitor rapamycin inhibited the function of UBE2T in BCSCs.Conclusion:UBE2T plays a role in BCSCs through mTOR pathway and may suggest a novel therapeutic strategy for breast cancer.

Wild pink bayberry free phenolic extract induces mitochondria-dependent apoptosis and G0/G1 cell cycle arrest through p38/MAPK and PI3K/Akt pathway in MDA-MB-231 cancer cells

Polyphenol-rich foods have been shown to be good for cancer prevention as powerful antioxidants. In this study, the mechanisms of wild pink bayberry free phenolic extract(WPBFE)inhibiting the proliferation and inducing apoptotic of MDA-MB-231 breast cancer cells was examined. The main phenolic acids and flavonols in WPBFE were gallic acid((18.83 ± 0.44)μg/g FW)and myricetin((1.52 ± 0.05)μg/g FW), respectively. The maximum inhibition rate of WPBFE at non-cytotoxicity dose(below 80 mg/mL)was 81%. Western blotting analysis showed that WPBFE could cause the arrest of cell cycle in G0/G1 phase by down-regulating expression levels of PCNA, CDK4, cyclin D1 and up-regulating the expression level of p21. Meanwhile, WPBFE induced apoptosis through initiating the mitochondrial death pathway by up-regulating cleaved caspase-3 and enhancing the ratio of Bax/Bcl-2, with the maximum expression levels of 1.29 and 2.03 folds that of control group, respectively. Further study of the upstream protein, we found that WPBFE down-regulated TRAF2, while upregulated p-ASK1, p-p38 and p-p53. Furthermore, WPBFE could down-regulate the expression of p-PI3K and p-Akt. These observations indicated that WPBFE might play an anticancer role through regulating the p38 MAPK together with PI3K/Akt pathway.

Role of cancer stem cell ecosystem on breast cancer metastasis and related mouse models

Breast cancer metastasis is responsible for most breast cancer-related deaths and is influenced by many factors within the tumor ecosystem,including tumor cells and microenvironment.Breast cancer stem cells(BCSCs)constitute a small population of cancer cells with unique characteristics,including their capacity for self-renewal and differentiation.Studies have shown that BCSCs not only drive tumorigenesis but also play a crucial role in promoting metastasis in breast cancer.The tumor microenvironment(TME),composed of stromal cells,immune cells,blood vessel cells,fibroblasts,and microbes in proximity to cancer cells,is increasingly recognized for its crosstalk with BCSCs and role in BCSC survival,growth,and dissemination,thereby influencing metastatic ability.Hence,a thorough understanding of BCSCs and the TME is critical for unraveling the mechanisms underlying breast cancer metastasis.In this review,we summarize current knowledge on the roles of BCSCs and the TME in breast cancer metastasis,as well as the underlying regulatory mechanisms.Furthermore,we provide an overview of relevant mouse models used to study breast cancer metastasis,as well as treatment strategies and clinical trials addressing BCSC-TME interactions during metastasis.Overall,this study provides valuable insights for the development of effective therapeutic strategies to reduce breast cancer metastasis.

Single-cell analysis of tumor microenvironment and cell adhesion reveals that interleukin-1 beta promotes cancer cell proliferation in breast cancer

Background: Triple-negative breast cancer(TNBC), which is so called because of the lack of estrogen receptors(ER), progesterone receptors(PR), and human epidermal growth factor receptor 2(HER2) receptors on the cancer cells, accounts for 10%–15% of all breast cancers. The heterogeneity of the tumor microenvironment is high.However, the role of plasma cells controlling the tumor migration progression in TNBC is still not fully understood.Methods: We analyzed single-cell RNA sequencing data from five HER2 positive, 12ER positive/PR positive, and nine TNBC samples. The potential targets were validated by immunohistochemistry.Results: Plasma cells were enriched in TNBC samples, which was consistent with validation using data from The Cancer Genome Atlas. Cell communication analysis revealed that plasma cells interact with T cells through the intercellular adhesion molecule 2–integrin–aLb2 complex, and then release interleukin 1 beta(IL1B), as verified by immunohistochemistry, ultimately promoting tumor growth.Conclusion: Our results revealed the role of plasma cells in TNBC and identified IL1B as a new prognostic marker for TNBC.

Predicting the Prognosis and Immunotherapeutic Response of Triple-Negative Breast Cancer by Constructing a Prognostic Model Based on CD8+T Cell-Related Immune Genes

Objective Triple-negative breast cancer(TNBC)poses a significant challenge for treatment efficacy.CD8+T cells,which are pivotal immune cells,can be effectively analyzed for differential gene expression across diverse cell populations owing to rapid advancements in sequencing technology.By leveraging these genes,our objective was to develop a prognostic model that accurately predicts the prognosis of patients with TNBC and their responsiveness to immunotherapy.Methods Sample information and clinical data of TNBC were sourced from The Cancer Genome Atlas and METABRIC databases.In the initial stage,we identified 67 differentially expressed genes associated with immune response in CD8+T cells.Subsequently,we narrowed our focus to three key genes,namely CXCL13,GBP2,and GZMB,which were used to construct a prognostic model.The accuracy of the model was assessed using the validation set data and receiver operating characteristic(ROC)curves.Furthermore,we employed various methods,including Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway,immune infiltration,and correlation analyses with CD274(PD-L1)to explore the model's predictive efficacy in immunotherapeutic responses.Additionally,we investigated the potential underlying biological pathways that contribute to divergent treatment responses.Results We successfully developed a model capable of predicting the prognosis of patients with TNBC.The areas under the curve(AUC)values for the 1-,3-,and 5-year survival predictions were 0.618,0.652,and 0.826,respectively.Employing this risk model,we stratified the samples into high-and low-risk groups.Through KEGG enrichment analysis,we observed that the high-risk group predominantly exhibited enrichment in metabolism-related pathways such as drug and chlorophyll metabolism,whereas the low-risk group demonstrated significant enrichment in cytokine pathways.Furthermore,immune landscape analysis revealed noteworthy variations between(PD-L1)expression and risk scores,indicating that our model effectively predicted the response of patients to immune-based treatments.Conclusion Our study demonstrates the potential of CXCL13,GBP2,and GZMB as prognostic indicators of clinical outcomes and immunotherapy responses in patients with TNBC.These findings provide valuable insights and novel avenues for developing immunotherapeutic approaches targeting TNBC.

Decreased LDHB expression in breast tumor cells causes NK cell activation and promotes tumor progression

Objective: Abnormal metabolism is the underlying reason for breast cancer progression. Decreased lactate dehydrogenase B(LDHB) has been detected in breast cancer but the function of LDHB remains unknown.Methods: Western blot was used to analyze LDHB expression in breast cancer cells. The impact of LDHB on tumor cell migration and invasion was determined using Transwell assays, wound healing assays, and a mouse lung metastasis model. Subcutaneous tumor formation, a natural killer(NK) cell cytotoxicity assay, and flow cytometry evaluated NK cell activation. Immunofluorescence and quantitative real-time PCR detected NK cell activation markers. Kaplan-Meier analysis evaluated the effect of immune cell infiltration on prognosis. Single-sample gene set enrichment analysis determined NK cell activation scores. A support vector machine predicted the role of LDHB in NK cell activation.Results: In this study we showed that LDHB inhibits the breast cancer cell metastasis and orchestrates metabolic reprogramming within tumor cells. Our results revealed that LDHB-mediated lactic acid clearance in breast cancer cells triggers NK cell activation within the tumor microenvironment. Our findings, which were confirmed in a murine model, demonstrated that LDHB in tumor cells promotes NK cell activation and ultimately results in the eradication of malignant cells. Clinically, our study further validated that LDHB affects immune cell infiltration and function. Specifically, its expression has been linked to enhanced NK cell-mediated cytotoxicity and improved patient survival. Furthermore, we identified LDHB expression in tumors as an important predictor of NK cell activation, with strong predictive ability in some cancers.Conclusions: Our results suggest that LDHB is a promising target for activating the tumor immune microenvironment in breast cancer, where LDHB-associated lactic acid clearance leads to increased NK cell activity. This study highlights the critical role of LDHB in regulating immune responses and its potential as a therapeutic target for breast cancer.

Elucidating the molecular basis of ATP-induced cell death in breast cancer: Construction of a robust prognostic model

BACKGROUND Breast cancer is a multifaceted and formidable disease with profound public health implications.Cell demise mechanisms play a pivotal role in breast cancer pathogenesis,with ATP-triggered cell death attracting mounting interest for its unique specificity and potential therapeutic pertinence.AIM To investigate the impact of ATP-induced cell death(AICD)on breast cancer,enhancing our understanding of its mechanism.METHODS The foundational genes orchestrating AICD mechanisms were extracted from the literature,underpinning the establishment of a prognostic model.Simultaneously,a microRNA(miRNA)prognostic model was constructed that mirrored the gene-based prognostic model.Distinctions between high-and low-risk cohorts within mRNA and miRNA characteristic models were scrutinized,with the aim of delineating common influence mechanisms,substantiated through enrichment analysis and immune infiltration assessment.RESULTS The mRNA prognostic model in this study encompassed four specific mRNAs:P2X purinoceptor 4,pannexin 1,caspase 7,and cyclin 2.The miRNA prognostic model integrated four pivotal miRNAs:hsa-miR-615-3p,hsa-miR-519b-3p,hsa-miR-342-3p,and hsa-miR-324-3p.B cells,CD4+T cells,CD8+T cells,endothelial cells,and macrophages exhibited inverse correlations with risk scores across all breast cancer subtypes.Furthermore,Kyoto Encyclopedia of Genes and Genomes analysis revealed that genes differentially expressed in response to mRNA risk scores significantly enriched 25 signaling pathways,while miRNA risk scores significantly enriched 29 signaling pathways,with 16 pathways being jointly enriched.CONCLUSION Of paramount significance,distinct mRNA and miRNA signature models were devised tailored to AICD,both potentially autonomous prognostic factors.This study's elucidation of the molecular underpinnings of AICD in breast cancer enhances the arsenal of potential therapeutic tools,offering an unparalleled window for innovative interventions.Essentially,this paper reveals the hitherto enigmatic link between AICD and breast cancer,potentially leading to revolutionary progress in personalized oncology.

Research Progress of Breast Cancer Stem Cell Stemness and Breast Cancer Recurrence

Currently, breast cancer is the most common malignant tumour in Chinese women with a high incidence rate, and recurrence and metastasis are the main reasons affecting survival. Breast Cancer Stem Cells (BCSCs) are stem cells capable of continuous regeneration in vivo with strong self-renewal ability and multidirectional differentiation potential, which are highly tumourigenic and insensitive to radiotherapy and chemotherapy, and are highly susceptible to breast cancer recurrence. Therefore, exploring the stemness of BCSCs and their mechanism associated with recurrence is important for developing new therapeutic strategies, improving therapeutic efficacy, and improving patient prognosis.

Circulating tumor cells and circulating tumor DNA in breast cancer diagnosis and monitoring

Liquid biopsy,including both circulating tumor cells and circulating tumor DNA,is becoming more popular as a diagnostic tool in the clinical management of breast cancer.Elevated concentrations of these biomarkers during cancer treatment may be used as markers for cancer progression as well as to understand the mechanisms underlying metastasis and treatment resistance.Thus,these circulating markers serve as tools for cancer assessing and monitoring through a simple,non-invasive blood draw.However,despite several study results currently noting a potential clinical impact of ctDNA mutation tracking,the method is not used clinically in cancer diagnosis among patients and more studies are required to confirm it.This review focuses on understanding circulating tumor biomarkers,especially in breast cancer.

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

Activation of Rac1-PI3K/Akt is required for epidermal growth factorinduced PAK1 activation and cell migration in MDA-MB-231 breast cancer cells

Epidermal growth factor （EGF） may increase cell motility, an event implicated in cancer cell invasion and metastasis. However, the underlying mechanisms for EGF-induced cell motility remain elusive. In this study, we found that EGF treatment could activate Ras-related C3 botulinum toxin substrate 1 （Racl）, PI3K/Akt and p21- actived kinase （PAK1） along with cell migration. Ectopic expression of PAK1 K299R, a dominant negative PAK1 mutant, could largely abolish EGF-induced cell migration. Blocking PI3K/Akt signalling with LY294002 or Akt siRNA remarkably inhibited both EGF-induced PAK1 activation and cell migration. Furthermore, expression of dominant-negative Racl （T17N） could largely block EGF-induced PI3K/Akt-PAK1 activation and cell migration. Interestingly, EGF could induce a significant production of ROS, and N-acetyl-L-cysteine, a scavenger of ROS which abolished the EGF-induced ROS generation, cell migration, as well as activation of PI3K/Akt and PAK, but not Racl. Our study demonstrated that EGF-induced cell migration involves a cascade of signalling events, including activation of Racl, generation of ROS and subsequent activation of PI3K/Akt and PAK1.

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.

Combinatorial effect of diclofenac with piperine and D-limonene on inducing apoptosis and cell cycle arrest of breast cancer cells

Objective:To investigate the potential synergistic activity of diclofenac with piperine and D-limonene in inducing apoptosis and cell cycle arrest in breast cancer MCF-7 cells.Methods:Molecular docking study was conducted to evaluate the binding affinity of diclofenac with piperine and D-limonene against p53,Bax,and Bcl-2.The MTT assay was used to determine IC50,and the Chou-Talay method was used to determine the synergistic concentration of the combination treatment of diclofenac plus piperine and diclofenac plus D-limonene.Apoptosis detection,cell cycle arrest,reactive oxygen species production,and mitochondrial membrane potential were also investigated.Results:Diclofenac,piperine,and D-limonene showed potent binding affinity for p53,Bax,and Bcl-2.Diclofenac plus piperine and diclofenac plus D-limonene enhanced the formation of reactive oxygen species,which also had an effect on the mitochondrial membrane’s integrity and caused DNA fragmentation.Diclofenac plus piperine and diclofenac plus D-limonene arrested the cells in the sub-G0phase while drastically lowering the percentage of cells in the G2/M phase.Furthermore,the elevated apoptosis in the combined therapy was confirmed by annexin V/propidium iodide staining.Conclusions:The combined therapy prominently enhanced the antiproliferative and apoptotic effects on MCF-7 cells compared with treatment with diclofenac,piperine,and D-limonene alone.

Senescent mesenchymal stem/stromal cells in pre-metastatic bone marrow of untreated advanced breast cancer patients

Breast cancer is the predominant form of carcinoma among women worldwide,with 70%of advanced patients developing bone metastases,with a high mortality rate.In this sense,the bone marrow(BM)mesenchymal stem/stromal cells(MSCs)are critical for BM/bone homeostasis,and failures in their functionality,transform the BM into a premetastatic niche(PMN).We previously found that BM-MSCs from advanced breast cancer patients(BCPs,infiltrative ductal carcinoma,stage III-B)have an abnormal profile.This work aims to study some of the metabolic and molecular mechanisms underlying MSCs shift from a normal to an abnormal profile in this group of patients.A comparative analysis was undertaken,which included self-renewal capacity,morphology,proliferation capacity,cell cycle,reactive oxygen species(ROS)levels,and senescence-associatedβ‑galactosidase(SA‑β‑gal)staining of BMderived MSCs isolated from 14 BCPs and 9 healthy volunteers(HVs).Additionally,the expression and activity of the telomerase subunit TERT,as well as telomere length,were measured.Expression levels of pluripotency,osteogenic,and osteoclastogenic genes(OCT-4,SOX-2,M-CAM,RUNX-2,BMP-2,CCL-2,M-CSF,and IL-6)were also determined.The results showed that MSCs from BCPs had reduced,self-renewal and proliferation capacity.These cells also exhibited inhibited cell cycle progression and phenotypic changes,such as an enlarged and flattened appearance.Additionally,there was an increase in ROS and senescence levels and a decrease in the functional capacity of TERT to preserve telomere length.We also found an increase in pro-inflammatory/pro-osteoclastogenic gene expression and a decrease in pluripotency gene expression.We conclude that these changes could be responsible for the abnormal functional profile that MSCs show in this group of patients.

Role of adipose-derived stem cells in breast cancer

The clinical use of fat grafts for breast reconstruction post-mastectomy or radiotherapy has the disadvantages of limited retention and survival rates.To solve this problem,adipose-derived stem cells(ADSCs)have been suggested as an alternative cell source for breast reconstruction,because they are simple to access,have low immunogenicity,and support the survival of mature adipose grafts.However,despite their outstanding properties,the use of ADSCs in patients with breast cancer is controversial,and the oncological safety of this method has been questioned.The biological effects of ADSCs on breast cancer are complex,and clinical research on ADSC-assisted fat grafting is limited.Here,we review the current experimental findings on the effects of ADSCs on breast cancer,mainly focusing on the role of ADSCs in breast cancer proliferation and growth processes,such as epithelial-mesenchymal transition(EMT)and angiogenesis.We also discuss the safety of ADSCs in clinical breast reconstruction.

Relation between Neurotransmitters and NK Cells in Adrenal and Breast Cancer

Purpose: Data on microarray gene expression The Gene Expression Omnibus (GEO) provided information on gene expression. Transcription GEO provided two profiles of human NK cells from breast and adrenal tumors (GSE179509 and GSE143383). Data processing and normalization The Dseq2 tool in the R programming language was used to standardize the raw data from GEO. The following analyses were carried out: fold change and P-value analysis, volcano plot, network analysis, GEPIA, and David pathway analysis. In this paper, using Venny software, we discovered 2 genes that are shared by neurotransmitters and NK cells in breast cancer and adrenal cancer. Between these genes and the pathways, they are a part of, we discovered a network. Pathway analysis revealed that these genes are mostly linked to the neurotransmitter and apoptotic pathways. In breast and adrenal tumors, the genes HRH1 and GABRD were discovered to be connected to NK cells. In response to breast and adrenal tumors, almost all of these genes are effective. It is thus postulated that the diagnosis of breast and adrenal cancer may be affected by the up-or down-regulation of these genes. Methods: Microarray gene expression data gene expression data was obtained from the Gene Expression Omnibus (GEO) Transcription 2 profile data of human NK cells from human breast and adrenal cancers were obtained from GEO (GSE179509 and GSE143383). Processing and normalization of data the raw data from GEO were normalized with the Dseq2 package in the R software. Fold change and P value analysis, Volcano plot, network analysis, GEPIA, and David pathway analysis were performed. Results: In this article, we found genes common to neurotransmitters with NK cells in adrenal cancer and breast cancer with Venny program, resulting in 2 genes. We identified a network between these genes and pathways they belong to. Pathway analysis showed that these genes are mostly associated with apoptosis and neurotransmitters pathway. Conclusion: HRH1 and GABRD genes were found to be associated with NK cells in breast and adrenal cancers. Almost all these genes are effective in response to breast and adrenal cancers. Therefore, it is hypothesized that downregulation or upregulation of these genes may affect breast and adrenal cancer diagnosis.

Game-changing insights on vertebral skeletal stem cells in bone metastasis and therapeutic horizons

Greenblatt and his team have unveiled vertebral skeletal stem cells(vSSCs)as a critical player in the landscape of bone metastasis.This commentary delves into the transformative discoveries surrounding vSSCs,emphasizing their distinct role in bone metastasis compared to other stem cell lineages.We illuminate the unique properties and functions of vSSCs,which may account for the elevated susceptibility of vertebral bones to metastatic invasion.Furthermore,we explore the exciting therapeutic horizons opened by this newfound understanding.These include potential interventions targeting vSSCs,modulation of associated signaling pathways,and broader implications for the treatment and management of bone metastasis.By shedding light on these game-changing insights,we hope to pave the way for novel strategies that could revolutionize the prognosis and treatment landscape for cancer patients with metastatic bone disease.

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.

YC-1 exerts inhibitory effects on MDA-MB-468 breast cancer cells by targeting EGFR in vitro and in vivo under normoxic condition

3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole(YC-1),the hypoxia-inducible factor-1 alpha(HIF-1α) inhibitor,suppresses tumor proliferation and metastasis by down-regulating HIF-1α expression under hypoxic conditions.Our previous studies demonstrated that YC-1 inhibited breast cancer cell proliferation under normoxic conditions.In the current study,we investigated the targets of YC-1 and mechanism of its action in MDA-MB-468 breast cancer cells.In the in vitro experiments,we found that YC-1 significantly inhibited MDA-MB-468 cell proliferation in normoxia and hypoxia.Under normoxic conditions,YC-1 induced apoptosis of MDA-MB-468 cells and blocked cell cycle in the G1 phase,and these effects were possibly related to caspase 8,p21,and p27 expression.RT-PCR and Western blotting results showed that YC-1 primarily inhibited HIF-1α at the mRNA and protein levels under hypoxic conditions,but suppressed the expression of epidermal growth factor receptor(EGFR) at the mRNA and protein levels under normoxic conditions.In vivo,YC-1 prolonged survival,increased survival rate,decreased tumor size and metastasis rate,and inhibited tissue EGFR and HIF-1α expression.However,YC-1 exerted no obvious effect on body weight.These results indicate that YC-1 inhibits the proliferation of MDA-MB-468 cells by acting on multiple targets with minimal side effects.Thus,YC-1 is a promising target drug for breast cancer.