Kruppel-like factor 4 induces apoptosis and inhibits tumorigenic progression in SK-BR-3 breast cancer cells.
Ontology highlight
ABSTRACT:
SUBMITTER: Wang B
PROVIDER: S-EPMC4359971 | biostudies-literature | 2015
REPOSITORIES: biostudies-literature
Publications
Krüppel-like factor 4 induces apoptosis and inhibits tumorigenic progression in SK-BR-3 breast cancer cells.
Wang Bing B Zhao Ming-Zhi MZ Cui Nai-Peng NP Lin Dan-Dan DD Zhang An-Yi AY Qin Yan Y Liu Cai-Yun CY Yan Wei-Tao WT Shi Jian-Hong JH Chen Bao-Ping BP
FEBS open bio 20150302
Krüppel-like factor 4 (KLF4) functions as either a tumor suppressor or an oncogene in different tissues by regulating the expression of various genes. The aim of this study was to reveal the functions of KLF4 in regulating breast cancer apoptosis, proliferation, and tumorigenic progression. KLF4 expression levels in breast cancer tissues and breast cancer cell lines were found to be much lower than those in nontumorous tissues and a nontransformed mammary epithelial cell line. KLF4 was upregulat ...[more]
Similar Datasets
Project description:Krüppel-like factor 4 (KLF4) is a zinc finger transcription factor that functions as an oncogene or tumor suppressor in a highly tissue-specific cell-dependent manner. However, its precise role in breast cancer and metastasis remains unclear. Here, we show that transient adenoviral expression of KLF4 in the 4T1 orthotopic mammary cancer model significantly attenuated primary tumor growth as well as micrometastases to the lungs and liver. These results can be attributed, in part, to decreased proliferation and increased apoptosis. Further supporting a tumor-suppressive role for KLF4 in the breast, we found that KLF4 expression is lost in a mouse model of HER2/NEU/ERBB2-positive breast cancer. To determine whether enforced KLF4 expression could alter tumor latency in these mice, we used a doxycycline-inducible expression model in the context of the MMTV-Neu transgene. Surprisingly, tumors that developed in this model also lost KLF4 expression, suggesting negative selection for sustained expression. We have previously reported that KLF4 inhibits epithelial-to-mesenchymal transition (EMT), a preliminary step in metastatic progression. Overexpression of KLF4 in 4T1 cells led to a significant reduction in the expression of Snail, a key mediator of EMT and metastasis. Conversely, KLF4 silencing increased Snail expression in the nontransformed MCF-10A cell line. Collectively, these data demonstrate the first functional, in vivo evidence for KLF4 as a tumor suppressor in breast cancer cells. Furthermore, our findings suggest an inhibitory role for KLF4 during breast cancer metastases that functions, in part, through repression of Snail.
| S-EPMC3132846 | biostudies-other
Project description:BackgroundThe tumour microenvironment is a critical regulator of malignant cancer progression. While endothelial cells have been widely studied in the context of tumour angiogenesis, their role as modulators of cancer cell invasion and migration is poorly understood.MethodsWe have investigated the influence of endothelial cells on the invasive and migratory behaviour of human cancer cells in vitro.ResultsUpon exposure to culture supernatants of endothelial cells, distinct cancer cells, such as SK-BR-3 cells, showed significantly increased invasion and cell migration concomitant with changes in cell morphology and gene expression reminiscent of an epithelial-mesenchymal transition (EMT). Interestingly, the pro-migratory effect on SK-BR-3 cells was significantly enhanced by supernatants obtained from subconfluent, proliferative endothelial cells rather than from confluent, quiescent endothelial cells. Systematically comparing the supernatants of subconfluent and confluent endothelial cells by quantitative MS proteomics revealed eight candidate proteins that were secreted at significantly higher levels by confluent endothelial cells representing potential inhibitors of cancer cell migration. Among these proteins, nidogen-1 was exclusively expressed in confluent endothelial cells and was found to be necessary and sufficient for the inhibition of SK-BR-3 cell migration. Indeed, SK-BR-3 cells exposed to nidogen-1-depleted endothelial supernatants showed increased promigratory STAT3 phosphorylation along with increased cell migration. This reflects the situation of enhanced SK-BR-3 migration upon stimulation with conditioned medium from subconfluent endothelial cells with inherent absence of nidogen-1 expression.ConclusionThe identification of nidogen-1 as an endothelial-derived inhibitor of migration of distinct cancer cell types reveals a novel mechanism of endothelial control over cancer progression.
| S-EPMC6449935 | biostudies-literature
Project description:Breast cancer is the most common cancer in women. The human epidermal growth factor receptor 2 (HER2) overexpressing subtype is related to poor prognosis with an aggressive phenotype and is reported as one of the most commonly seen subtypes. Trastuzumab is prevalently used as a treatment method for HER2+ breast cancer however, resistance to the drug frequently occurs following the treatment. MicroRNAs (miRNAs) are 19-23 nucleotide long small RNAs, which regulate gene expression at post-transcriptional level and studies show that there are differentially expressed miRNAs between drug sensitive and resistant groups, indicating that they might have some key roles in drug effectiveness. In this study, the aim is to find out the role of miR-216b-5p in trastuzumab resistance. SK-BR-3 cells developed resistance to trastuzumab after continuous treatment with increasing concentrations of the drug for 6 months. To investigate the effect of miR-216b-5p on cancer cell behavior in resistance state, proliferation, motility, and invasion capacities of these resistant cells were analyzed by xCELLigence real-time cell analyzer. To further understand the molecular mechanisms underlying the regulation of resistant SK-BR-3 cells by miR-216b-5p, microarray analysis was performed. Apoptosis analysis was also performed since the pathway enrichment analysis pointed out cell death related pathways. The proliferation, motility, and invasion capacities of the miR-216b-5p transfected resistant cells were diminished compared to sensitive cells. We identified the necroptosis signaling pathway as the result of microarray and pathway enrichment analyses. STAT1, IRF9, and PKR were validated as the significant elements of the pathway, which are also the putative targets of miR-216b-5p. Our apoptosis analysis showed that a significant amount of trastuzumab resistant SK-BR-3 cells entered to late apoptosis/necrosis stage upon miR-216b-5p overexpression, it could be concluded that reexpression of miR-216b-5p sensitizes trastuzumab resistance through necroptosis in breast cancer.
| S-EPMC10387915 | biostudies-literature
Project description:8-Chloro-adenosine (8-Cl-Ado) has been shown to exhibit its antitumor activity by inducing apoptosis in human lung cancer A549 and H1299 cells or autophagy in chronic lymphocytic leukemia, and MDA-MB-231 and MCF-7 breast cancer cells. Adenosine deaminases acting on RNA 1 (ADAR1) is tightly associated with cancer development and progression. The aim of this study was to investigate the role of ADAR1 in the proliferation of MDA-MB-231 and SK-BR-3 breast cancer cell lines after 8-Cl-Ado exposure and its possible mechanisms. After 8-Cl-Ado exposure, CCK-8 assay was performed to determine the cell proliferation; flow cytometry was used to analyze the cell cycle profiles and apoptosis; and the protein levels of ADAR1, p53, p21, and cyclin D1 were measured by western blotting. The results showed that the cell proliferation was greatly inhibited, G1 cell cycle was arrested, and apoptosis was induced after 8-Cl-Ado exposure. ADAR1 and cyclin D1 protein levels were dramatically decreased, while p53 and p21 levels were increased after 8-Cl-Ado exposure. Moreover, the cell growth inhibition was rescued, apoptosis was reduced, and p53 and p21 protein levels were downregulated, while cyclin D1 was upregulated when cells were transfected with plasmids expressing ADAR1 proteins. More importantly, RNA-binding domain of ADAR1 is critical to the cell growth inhibition of breast cancer cells exposed to 8-Cl-Ado. Together, 8-Cl-Ado inhibits the cell proliferation, induces G1 phase arrest and apoptosis at least by targeting ADAR1/p53/p21 signaling pathway. The findings may provide us with insights into the role of ADAR1 in breast cancer progression and help us better understand the effects of 8-Cl-Ado in the treatment of breast cancer.
| S-EPMC7784596 | biostudies-literature
Project description:Retinoblastoma (RB) is the most common primary intraocular malignancy in children. Intravitreal chemotherapy achieves favorable clinical outcomes in controlling RB vitreous seeds, which are a common reason for treatment failure. Thus, a novel, effective and safe intravitreal chemotherapeutic drug is urgently required. The malaria drug artesunate (ART) recently demonstrated remarkable anticancer effects with mild side effects. The purpose of this study is to investigate the anti-RB efficacy, the underlying mechanism and the intraocular safety of ART. Herein, we verified that ART inhibits RB cell viability and induces cell apoptosis in a dose- and time-dependent manner. Microarray analysis revealed that Kruppel-like factor 6 (KLF6) was upregulated after ART treatment, and this was further confirmed by real-time PCR and western blot assays. Silencing of KLF6 expression significantly reversed ART-induced RB cell growth inhibition and apoptosis. Furthermore, ART activated mitochondria-mediated apoptosis of RB cells, while silencing KLF6 expression significantly inhibited this effect. In murine xenotransplantation models of RB, we further confirmed that ART inhibits RB tumor growth, induces tumor cell apoptosis and upregulates KLF6 expression. In addition, KLF6 silencing attenuates ART-mediated inhibition of tumor growth in vivo. Furthermore, we proved that intravitreal injection of ART in Sprague-Dawley (SD) rats is safe, with no obvious retinal function damage or structural disorders observed by electrophysiology (ERG), fundal photographs, fundus fluorescein angiography (FFA) or optical coherence tomography (OCT) examinations. Collectively, our study revealed that ART induces mitochondrial apoptosis of RB cells via upregulating KLF6, and our results may extend the application of ART to the clinic as an effective and safe intravitreal chemotherapeutic drug to treat RB, especially RB with vitreous seeds.
| S-EPMC6853908 | biostudies-literature
Project description:Y-box-binding protein 1 (YB1) is a multifunctional transcription factor with vital roles in proliferation, differentiation and apoptosis. In this study, we have examined the role of its C-terminal domain (YB1 CTD) in proliferation, angiogenesis and tumorigenicity in breast cancer. Breast cancer cell line SK-BR-3 was infected with GFP-tagged YB1 CTD adenovirus expression vector. An 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) proliferation assay showed that YB1 CTD decreased SK-BR-3 cell proliferation, and down-regulated cyclin B1 and up-regulated p21 levels in SK-BR-3 cells. YB1 CTD overexpression changed the cytoskeletal organization and slightly inhibited the migration of SK-BR-3 cells. YB1 CTD also inhibited secreted VEGF expression in SK-BR-3 cells, which decreased SK-BR-3-induced EA.hy926 endothelial cell angiogenesis in vitro. YB1 CTD overexpression attenuated the ability of SK-BR-3 cells to form tumours in nude mice, and decreased in vivo VEGF levels and angiogenesis in the xenografts in SK-BR-3 tumour-bearing mice. Taken together, our findings demonstrate the vital role of YB1 CTD overexpression in inhibiting proliferation, angiogenesis and tumorigenicity of breast cancer cell line SK-BR-3.
| S-EPMC4794790 | biostudies-other
Project description:BackgroundBisphosphonates (BPs) were designed for the prevention of skeletal-related events secondary to bone metastases. The purpose of this study was to show that zoledronic acid (ZA) directly eradicates highly tumorigenic and potentially metastatic cancer cells.Materials and methodsHuman prostate and breast highly tumorigenic (PC3, MCF 7) and low- or non-tumorigenic (LNCaP, MCF 10a) cell lines, respectively, were exposed to different concentrations of ZA (0-10 μM). Reverse transcriptase double quantitative polymerase chain reaction was used for quantitative gene expression analysis. Apoptosis and cell proliferation were determined using microscopic observation and MTS assays. Western blot was used to confirm the translational effects of apoptotic genes on protein expression.ResultsHuman prostate and breast highly tumorigenic (PC3, MCF 7) and low- or non-tumorigenic (LNCaP, MCF 10a) cell lines, respectively, showed multiple genes demonstrating differential expressions, including TRAF, TRADD, BCL2, CASPASES and IAP families. Increasing ZA concentrations showed a greater concentration-time response on cell proliferation and apoptosis in the highly tumorigenic cells. These results were confirmed by both reversing and enhancing the effect of ZA on cell proliferation with caspase 3, 7 or survivin siRNA, respectively. Pro-apoptotic proteins bax and caspase 2, 3, 7 and 9 were up-regulated, while the anti-apoptotic proteins bcl2, birc3 and survivin were down-regulated only in the highly tumorigenic cells.ConclusionsThis explains the ability of ZA to inhibit bony metastasis in highly tumorigenic cells compared with the low- or non-tumorigenic cells through a significant decrease in cell proliferation and increase in apoptosis through gene-regulated and translational-mediated down-regulation of survivin coupled with the inhibition of caspase 3 or 7. This has significant implications toward understanding the pharmacophysiology of BPs in metastasis and supports the clinically observed effect of BPs when administered adjunctively with anticancer drugs such as cyclophosphamide/methotrexate/5-fluorouracil, epirubicin in combination with cyclophosphamide or docetaxel, and doxorubicin.
| S-EPMC3030761 | biostudies-literature
Project description:Normalization of gene expression using internal controls or reference genes (RGs) has been the method of choice for standardizing the technical variations in reverse transcription quantitative polymerase chain reactions (RT-qPCR). Conventionally, ACTB and GAPDH have been used as reference genes despite evidence from literature discouraging their use. Hence, in the present study we identified and investigated novel reference genes in SK-BR-3, an HER2-enriched breast cancer cell line. Transcriptomic data of 82 HER2-E breast cancer samples from TCGA database were analyzed to identify twelve novel genes with stable expression. Additionally, thirteen RGs from the literature were analyzed. The expression variations of the candidate genes were studied over five successive passages (p) in two parallel cultures S1 and S2 and in acute and chronic hypoxia using various algorithms. Finally, the most stable RGs were selected and validated for normalization of the expression of three genes of interest (GOIs) in normoxia and hypoxia. Our results indicate that HSP90AB1, DAD1, PFN1 and PUM1 can be used in any combination of three (triplets) for optimizing intra- and inter-assay gene expression differences in the SK-BR-3 cell line. Additionally, we discourage the use of conventional RGs (ACTB, GAPDH, RPL13A, RNA18S and RNA28S) as internal controls for RT-qPCR in SK-BR-3 cell line.
| S-EPMC8535678 | biostudies-literature
Project description:Medicinal plant-based therapies can be important for treatment of cancer owing to high efficiency, low cost and minimal side effects. Here, we report the anti-cancer efficacy of Ricinus communis L. fruit extract (RCFE) using estrogen positive MCF-7 and highly aggressive, triple negative MDA-MB-231 breast cancer cells. RCFE induced cytotoxicity in these cells in dose and time-dependent manner. It also demonstrated robust anti-metastatic activity as it significantly inhibited migration, adhesion, invasion and expression of matrix metalloproteinases (MMPs) 2 and 9 in both cell lines. Further, flow cytometry analysis suggested RCFE-mediated induction of apoptosis in these cells. This was supported by attenuation of anti-apoptotic Bcl-2, induction of pro-apoptotic Bax and caspase-7 expressions as well as PARP cleavage upon RCFE treatment. RCFE (0.5?mg/Kg body weight) treatment led to significant reduction in tumor volume in 4T1 syngeneic mouse model. HPLC and ESI-MS analysis of active ethyl acetate fraction of RCFE detected four compounds, Ricinine, p-Coumaric acid, Epigallocatechin and Ricinoleic acid. Individually these compounds showed cytotoxic and migration-inhibitory activities. Overall, this study for the first time demonstrates the anti-cancer efficacy of the fruit extract of common castor plant which can be proposed as a potent candidate for the treatment of breast cancer.
| S-EPMC6787038 | biostudies-literature
Project description:Introduction:A disintegrin and metallopeptidase with thrombospondin motifs (ADAMTSs), whose expression is dysregulated in various cancers, is implicated in cancer development. Herein, we aimed to investigate the functional role of ADAMTS8 in breast cancer (BC) and explore the underlying mechanisms. Methods:The protein expression of ADAMTS8 in BC cell lines and tumor tissues from BC patients was quantified by Western blot. ADAMTS8 overexpression was induced by transfection with pEZ-M90-ADAMTS8 plasmid using lipofectamine 2000. To generate ADAMTS8 stable knockdown cells, MDA-MB-231 cells were transfected with psi-H1-ADAMTS8siRNA plasmids. Cell counting kit-8 (CCK-8) assay, wound-healing assay, transwell assay and flow cytometry assay were employed to analyze the effects of ADAMTS8 on the proliferation, migration, invasion and apoptosis of BC cells. Chemosensitivity also was assessed using CCK-8 assay. The expressions of ?-catenin, MMP-7 and c-Myc were measured by Western blot. Results:Our results showed that ADAMTS8 expression was significantly lower in BC tissues than that in adjacent non-tumor tissues. Overexpression of ADAMTS8 in MDA-MB-453 cells could inhibit the cell proliferation, migration and invasion and promote apoptosis. ADAMTS8 knockdown displayed the reverse effect in MDA-MB-231 cells. Consistently, in vivo data showed that ADAMTS8 overexpression led to a reduction in tumor growth. In addition, chemosensitivity testing in MDA-MB-453 cells transfected with pEZ-M90-ADAMTS8 plasmid indicated that cisplatin inhibited cell growth dramatically. Furthermore, attenuated ?-catenin, MMP-7 and c-Myc level was detected after ADAMTS8 overexpression. Conclusion:These results indicate that increased ADAMTS8 expression could modify the progression of BC by inhibiting cell proliferation and invasion while promoting the apoptosis of BC cells. Thus, ADAMTS8 represents a potential therapeutic target for BC therapy.
| S-EPMC7457586 | biostudies-literature