Project description:The transcription factor POU1F1 plays an important role in breast cancer. It has been described that POU1F1 is capable of regulating the expression of different genes involved in cell proliferation, apoptosis and cell plasticity. The mechanism by which POU1F1 carries out these regulations is still unknown, and epigenetics is one of the possible causes. Epigenetics refers to modifications in gene expression that are heritable through cell division and that occur without changes in the DNA sequence. DNA methylation is one of the most important epigenetic mechanisms.
Project description:The aim of the study is to evaluate Pit-1-induced genes in the MCF-7 cell line The Pit-1 transcription factor (also known as POU1F1) plays a critical role in cell differentiation during organogenesis of the anterior pituitary in mammals and is a transcriptional activator for pituitary gene transcription. Increased expression of Pit-1 has been reported in human tumorigenic breast cells. Here, we found that Pit-1 overexpression or knockdown in human breast cancer cell lines induced profound phenotypic changes in the expression of proteins involved in cell proliferation, apoptosis, and invasion. In immunodeficient mice, Pit-1 overexpression induced tumoral growth and promoted metastasis in lung. In patients with invasive ductal carcinoma of the breast and node-positive tumors elevated expression of Pit-1 was significantly and independently associated with the occurrence of distant metastasis. These findings suggest that Pit-1 could help to make a more accurate prognosis in patients with node positive breast cancer and may represent a new therapeutic target (Journal of Clinical Investigation 2010, 120:4289-4302) MCF-7 cells were transfected with the pcDNA3 (control, two samples as condition, named C1 and C2) or the pcDNA3-Pit-1 overexpression vector (two samples as condition, named 1+ and 2+) for 48 hours.
Project description:The aim of the study is to evaluate Pit-1-induced genes in the MCF-7 cell line The Pit-1 transcription factor (also known as POU1F1) plays a critical role in cell differentiation during organogenesis of the anterior pituitary in mammals and is a transcriptional activator for pituitary gene transcription. Increased expression of Pit-1 has been reported in human tumorigenic breast cells. Here, we found that Pit-1 overexpression or knockdown in human breast cancer cell lines induced profound phenotypic changes in the expression of proteins involved in cell proliferation, apoptosis, and invasion. In immunodeficient mice, Pit-1 overexpression induced tumoral growth and promoted metastasis in lung. In patients with invasive ductal carcinoma of the breast and node-positive tumors elevated expression of Pit-1 was significantly and independently associated with the occurrence of distant metastasis. These findings suggest that Pit-1 could help to make a more accurate prognosis in patients with node positive breast cancer and may represent a new therapeutic target (Journal of Clinical Investigation 2010, 120:4289-4302)
Project description:POU1F1 (also named PIT-1) is a well-known transcription factor involved in embryonic and adult pituitary development that has also been analyzed for its role in breast cancer . This study provides compelling evidence of POU1F1 in reprogramming breast cancer cells into BCSC-like. Our data demonstrates that POU1F1 induces a BCSC-like phenotype in breast tumor cells by deregulating markers such as CD24, CD44, CD133, and ALDH. These phenotypic modifications are correlated with functional changes, i.e. higher clonogenicity, increased mammospheres formation, and increased glycolysis metabolism. In addition, using in vivo immunodeficient mice models we found that a subpopulation of ALDHhigh cells from the POU1F1 overexpressing MCF-7 cells possess high tumor-initiating capacity, high resistance to chemo- and radiotherapy, and reduced overall survival. Mechanistically, POU1F1 induces an increase in IL-6 mRNA expression and raises IL-6 in the culture medium. This activates the IL-6/JAK/STAT3 pathway, which in turn increases ALDH mRNA expression.
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: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.
Project description:Genome wide DNA methylation profiling of estrogene receptor postive breast cancer cell line MCF-7, treating proton beam. The Illumina Infinium Human Methylation 450k Bead chip was used to obtain DNA methylation profiles across approximately 450,000 CpGs. This profiling indicates that proton beam induces epigenetic and cellular changes. Genomic DNA obtained from MCF-7 effected by proton beam
Project description:Genome wide DNA methylation profiling of estrogene receptor postive breast cancer cell line MCF-7, treating proton beam. The Illumina Infinium Human Methylation 450k Bead chip was used to obtain DNA methylation profiles across approximately 450,000 CpGs. This profiling indicates that proton beam induces epigenetic and cellular changes.
Project description:Genome wide DNA methylation profiling of estrogene receptor postive breast cancer cell line MCF-7, treating atmospheric cold plasma (plasma). The Illumina Infinium Human Methylation 450k Bead chip was used to obtain DNA methylation profiles across approximately 450,000 CpGs. This profiling indicates that plasma induces epigenetic and cellular changes.