Project description:This experiment is designed to verify that the targeted CRISPRi indeed bind specifically at the intended site (KLF2 binding site 1 on the miR-125b-1 promoter) in MDA-MB-231 cells. At the same time, off-target binding can be explored.
Project description:Dicer, RNase III endonuclease, is an essential enzyme in miRNA biogenesis that regulates target gene expression, and it has been reported that aberrant expressions of Dicer associate with the clinical outcomes of patients in various cancers. To explore the miRNA differencial expression regulated by Dicer in MDA-MB-231/E1A cells, the microarray profiling analysis was employed to conduct differentially expressed miRNAs in stable MDA-MB-231/vector, MDA-MB-231/E1A, and MDA-MB-231/E1A/shDicer cells.
Project description:Dicer, RNase III endonuclease, is an essential enzyme in miRNA biogenesis that regulates target gene expression, and it has been reported that aberrant expressions of Dicer associate with the clinical outcomes of patients in various cancers. To explore the miRNA differencial expression regulated by Dicer in MDA-MB-231/E1A cells, the microarray profiling analysis was employed to conduct differentially expressed miRNAs in stable MDA-MB-231/vector, MDA-MB-231/E1A, and MDA-MB-231/E1A/shDicer cells. The four groups including vector control, E1A-expressing and Dicer knockdown in E1A-expressing MDA-MB-231 cells were harvested and RNA were isolated. Two independent experiments were performed for each group.
Project description:CRISPRi on PVT1 did not induce drastic changes on chromatin accessbility in MDA-MB-231 cell line. CCAT1 enhancer is accessble specifically in HCT116, not in MCF7 or MDA-MB-231.
Project description:Identification of genes that are involved in self-seeding by comparing gene expression profiles between parental MDA-MB-231 cells and seeder cells (MDA-231-S1a and S1b) 2 replicates from each sample (parental MDA-MB-231, MDA-MB-231 S1a and MDA-MB-231 S1b) were analyzed
Project description:Identification of genes that are involved in self-seeding by comparing gene expression profiles between parental MDA-MB-231 cells and seeder cells (MDA-231-S1a and S1b)
Project description:Since bone metastatic breast cancer is an incurable disease, causing significant morbidity and mortality, understanding of the underlying molecular mechanisms would be highly valuable. Here, we describe in vitro and in vivo evidence for the importance of serine biosynthesis in the metastasis of breast cancer to bone. We first characterized the bone metastatic propensity of the MDA-MB-231(SA) cell line variant as compared to the parental MDA-MB-231 cells by radiographic and histological observations in the inoculated mice. Genome-wide gene expression profiling of this isogenic cell line pair revealed that all the three genes involved in the L-serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH) were upregulated in the highly metastatic variant. This pathway is the primary endogenous source for L-serine in mammalian tissues. Consistently, we observed that the proliferation of MDA-MB-231(SA) cells in serine-free conditions was dependent on PSAT1 expression. In addition, we observed that L-serine is essential for the formation of bone resorbing human osteoclasts and may thus contribute to the vicious cycle of osteolytic bone metastasis. High expression of PHGDH and PSAT1 in primary breast cancer was significantly associated with decreased relapse-free and overall survival of patients and malignant phenotypic features of breast cancer. In conclusion, high expression of serine biosynthesis genes in metastatic breast cancer cells and the stimulating effect of L-serine on osteoclastogenesis and cancer cell proliferation indicate a functionally critical role for serine biosynthesis in bone metastatic breast cancer and thereby an opportunity for targeted therapeutic interventions. Parental MDA-MB-231 cells and MDA-MB-231(SA) cells were cultured in cell culture flasks. RNA was isolated in order to compare the gene expression profiles of these cell variants. Total of two samples. No replicates.
Project description:LRP-1 (low-density lipoprotein receptor-related protein-1) receptor is a multifunctional endocytosis receptor that is part of the LDL receptor family. Due to its capacity to control the pericellular level of various growth factors and proteases, LRP-1 plays a crucial role in controlling the dynamics of the membrane proteome. LRP-1 overexpression in breast cancer, prompted us to take an interest in its involvement in tumor progression. An RNA interference strategy in MDA-MB-231 line was used, based on shRNA stable expression. In addition to integrated experimental strategies (in vitro and in vivo) through combined approaches of biochemistry, molecular biology, cell biology, multimodal preclinical imaging, proteomics allowed us to compare shLRP-1 MDA-MB-231 tumor conditioned media to shCtrl MDA-MB-231 tumor conditioned media in order to identify secreted molecular targets modulate by LRP-1 repression and thus provide a better understanding of its regulatory action within the TNBC microenvironment.