Expression data for knockdown of POLRMT or RNA PolII in MCF-7 cell line
Ontology highlight
ABSTRACT: Transcription of mRNA in mammalian is mainly performed by RNA polymerase II (PolII). POLRMT is responsible for the production of cytoplasmic and nuclear form of mitochondrial RNA polymerase. The former (mtRNAP) participates in transcription of RNA in the mitochondria while the latter (spRNAP-IV) is responsible for some mRNA transcription in the nucleus. The nature and amount of genes transcribed by spRNAP-IV still remains unclear. Thus, we scanned for possible candidate genes by using Affymetrix. MCF-7 cell line was subjected to siRNA knockdown of either non-targeting, POLRMT, or PolII for 72 hours
Project description:Estrogens(E2) are important steroid hormones that regulate differentiation, proliferation, and apoptosis in hormone-dependent breast cancer.In order to detect the E2-dependent transcription program associated with the observed cell cycle response, we analyzed the effect of H2ac knockdown on MCF-7 gene expression using microarray. Interestingly, we noticed that 51% of the E2-upregulated genes are down-regulated by depletion of H2ac. The data also show that H2ac regulated E2-dependent genes through E2-induction signaling pathway. MCF-7 cell line was transfected with scrambled or H2ac siRNA in the absence or persence of E2.
Project description:miR-21 is overexpressed in breast cancer cells. Knock-down of miR-21 cause apoptosis and decreased cell proliferation. To identify miR-21 regulated cancer-pathways in MCF-7 cells, we knocked-down miR-21 and performed microarray. RNA was harvested from MCF-7 cells 24 hours transfection of anti-control, anti-21, or untreated cells. RNA was processed and hybridized into Affymetrix whole human genome arrays in duplicates.
Project description:Understanding the molecular underpinnings of chemoresistance is vital to design therapies to restore chemosensitivity. In particular, metadherin (MTDH) has been demonstrated to have a critical role in chemoresistance. Over-expression of MTDH has recently been implicated in poor clinical outcome in breast cancer, neroblastoma, hepatocellular carcinoma and prostate cancer. In this present study, we focused on the therapeutic benefit of MTDH depletion to restore sensitivity to cell death mediated by a combinatorial therapy of tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL), which promotes death of cancerous cells of the human reproductive tract, and histone deacetylase (HDAC) inhibitors, which have been shown to increase sensitivity of cancer cells to TRAIL-induced apoptosis. Our data indicate that depletion of MTDH in endometrial cancer cells results in sensitization of cells that were previously resistant to cell death mediated by combinatorial treatment with TRAIL and HDAC inhibitor LBH589. MTDH was found to be involved in G2/M checkpoint regulation in response to LBH589 alone or LBH589 in combination with TRAIL, suggesting that MTDH functions at the cell cycle checkpoint to accomplish resistance.Using microarray technology, we identified 57 downstream target genes of MTDH, including Calbindin 1 and Galectin 1, which may contribute to MTDH-mediated resistance to combinatorial TRAIL and HDAC inhibitor targeted therapy. Inhibition of PDK1,AKT phosphorylation and increase Bim expression and XIAP degradation may result in sensitivity to cell death induction in MTDH depleted Hec50co cells by TRAIL and LBH 589 combination treatment. These findings indicate that depletion of MTDH is a potentially novel avenue for effective cancer therapy. The microarray was performed on three biological triplicates as well as three experimental triplictes of stable knockdown and control cells. MTDH was knocked down using a shRNA.
Project description:Transcription of mRNA in mammalian is mainly performed by RNA polymerase II (PolII). POLRMT is responsible for the production of cytoplasmic and nuclear form of mitochondrial RNA polymerase. The former (mtRNAP) participates in transcription of RNA in the mitochondria while the latter (spRNAP-IV) is responsible for some mRNA transcription in the nucleus. The nature and amount of genes transcribed by spRNAP-IV still remains unclear. Thus, we scanned for possible candidate genes by using Affymetrix.
Project description:The telomeric amplicon at 8p12 is common in ER+ breast cancers. Array-CGH and expression analyses of 1172 tumors revealed ZNF703/Zeppo1 was the single gene within the minimal amplicon and was amplified predominantly in the Luminal B subtype. Amplification was shown to correlate with increased gene and protein expression and was associated with a distinct expression signature and poor outcome. In the luminal MCF-7 cell line manipulation of ZNF703 expression altered transcription of genes also present within the primary tumor signature, including TGFBR2 (whose promoter was bound by ZNF703). Overexpression of ZNF703 rendered MCF-7 cells insensitive to TGFβ-induced suppression of mammosphere formation. Forced overexpression of ZNF703 in normal human breast epithelial cells enhanced the frequency of in vitro colony-forming cells from luminal progenitors. Together these data strongly point to ZNF703/Zeppo1 as a novel oncogene in Luminal B breast cancer. MCF-7 breast cancer cell line was infected with ZNF703 overexpression (ZNF703) or control (HIV) virus and following GFP sorting of infected cells, were transfected with control siRNA (siC) or siRNA against endogenous ZNF703 (siZNF), resulting in four different conditions: siC_HIV, siC_ZNF, siZNF_HIV and siZNF-ZNF. RNA for each condition was harvested from triplicate plates.
Project description:Transcription of mRNA in mammalian is mainly performed by RNA polymerase II (PolII). POLRMT is responsible for the production of cytoplasmic and nuclear form of mitochondrial RNA polymerase. The former (mtRNAP) participates in transcription of RNA in the mitochondria while the latter (spRNAP-IV) is responsible for some mRNA transcription in the nucleus. The nature and amount of genes transcribed by spRNAP-IV still remains unclear. Thus, we scanned for possible candidate genes by using Affymetrix. MCF-7 cell line was subjected to siRNA knockdown of either non-targeting, POLRMT, or PolII for 72 hours
Project description:Understanding the molecular underpinnings of chemoresistance is vital to design therapies to restore chemosensitivity. In particular, metadherin (MTDH) has been demonstrated to have a critical role in chemoresistance. Over-expression of MTDH has recently been implicated in poor clinical outcome in breast cancer, neroblastoma, hepatocellular carcinoma and prostate cancer. In this present study, we focused on the therapeutic benefit of MTDH depletion to restore sensitivity to cell death mediated by a combinatorial therapy of tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL), which promotes death of cancerous cells of the human reproductive tract, and histone deacetylase (HDAC) inhibitors, which have been shown to increase sensitivity of cancer cells to TRAIL-induced apoptosis. Our data indicate that depletion of MTDH in endometrial cancer cells results in sensitization of cells that were previously resistant to cell death mediated by combinatorial treatment with TRAIL and HDAC inhibitor LBH589. MTDH was found to be involved in G2/M checkpoint regulation in response to LBH589 alone or LBH589 in combination with TRAIL, suggesting that MTDH functions at the cell cycle checkpoint to accomplish resistance.Using microarray technology, we identified 57 downstream target genes of MTDH, including Calbindin 1 and Galectin 1, which may contribute to MTDH-mediated resistance to combinatorial TRAIL and HDAC inhibitor targeted therapy. Inhibition of PDK1,AKT phosphorylation and increase Bim expression and XIAP degradation may result in sensitivity to cell death induction in MTDH depleted Hec50co cells by TRAIL and LBH 589 combination treatment. These findings indicate that depletion of MTDH is a potentially novel avenue for effective cancer therapy. The microarray was performed on three biological triplicates as well as three experimental triplicates of stable knockdown and control cells. MTDH was knocked down using a shRNA.
Project description:Cisplatin treatment confers the relative resistance to MCF-7 cells as compared to other breast cancer cell lines. One principal reason is that chemotherapeutic agents induce autophagy in these cells to inhibit apoptosis. Binding immunoglobulin protein (BiP), a master regulator of unfolded protein response (UPR) and 14-3-3ζ are two critical proteins upregulated in breast cancer rendering resistance to anticancer drugs. They also play pivotal roles in autophagy with crosstalk with the apoptotic pathways of UPR through certain regulators. Thus, BiP and 14-3-3ζ were selected as the candidate targets to enhance cell death and apoptosis. First, cisplatin resistance was induced and determined by MTT assay and qPCR in MCF-7 cells. Then, the apoptosis axis of UPR was activated by knocking down either BiP or 14-3-3ζ and overactivated by co-knockdown of BiP and 14-3-3ζ. Apoptosis assays were performed using flow cytometry, TUNEL assays utilized confocal microscopy followed by western blot analysis and caspase-3 and JNK activities were investigated to assess the outcomes. Finally, an autophagy assay followed by western blotting was performed to study the effects of co-knockdown genes on cell autophagy in the presence and absence of cisplatin. The present data indicated the enhancement of cisplatin sensitivity in MCF-7 cells co-knocked down in BiP and 14-3-3ζ compared with either gene knockdown. Upregulation of JNK and cleaved-PARP1 protein levels as well as caspase-3 and JNK overactivation confirmed the results. A marked attenuation of autophagy and Beclin1 as well as ATG5 downregulation were detected in co-knockdown cells compared to knockdown with either BiP or 14-3-3ζ. Cisplatin sensitization of MCF-7 cells through double-knockdown of BiP and 14-3-3ζ highlights the potential of targeting UPR and autophagy factors to increase the effect of chemotherapy.
Project description:The transcription factor Snail has been proposed to mediate epithelial-to-mesenchymal transition (EMT) and confer mesenchymal invasive phenotype to epithelial cancer cells To analyze the molecular effects of ectopic Snail expression on an epithelial breast cancer cell line, gene expression profiles of MCF-7 cells transfected to overexpress Snail-6SA variant (MCF-7-Snail) and MCF-7 cells transfected with control plasmid (MCF-7-control) were compared. Development of the cell lines has been previously reported by Zhou et al. (PMID: 15448698). Dataset includes 3 replicate cultures of MCF-7-Snail cells and 3 replicate cultures of MCF-7-control cells
Project description:We demonstrate that AK4 down-regulation shRNAs significantly reduced cell migration and invasion in highly invasive lung cancer cell lines in vitro, as well as in lung metastases in vivo We used microarrays to analyze the AK4 regulated gene expression underlying invasion-metastasis cascade. CL1-0 lung adenocarcinoma cells with AK4 overexpression and CL1-5 cells with AK4 knockdown were selected for RNA extraction and hybridization on Affymetrix microarrays.