Project description:To assess the association of the nucleic acid binding protein yb-1 with mature microRNAs levels in breast cancer. To do this we performed YB-1 siRNA treatement in triplicates alongside an siRNA control Two breast cancer cell-lines, representative of Luminal A and Basal molecular subtypes were used, MCF7 and MDA-MB-435S.
Project description:To assess the association of the nucleic acid binding protein yb-1 with mature microRNAs levels in breast cancer. To do this we performed YB-1 siRNA treatement in triplicates alongside an siRNA control Two breast cancer cell-lines, representative of Luminal A and Basal molecular subtypes were used, MCF7 and MDA-MB-435S. Two cell-lines, treated with either siYB-1 or si-Ctrl in triplicate samples.
Project description:To assess the direct association of the nucleic acid binding protein yb-1 with mature microRNAs in breast cancer. To do this we performed immunoprecipitation (IP) of YB-1 protein to pull-down linked RNAs Two breast cancer cell-lines, representative of Luminal A and Basal molecular subtypes were used, MCF7 and MDA-MB-435S. An input control represents the RNA present in the lysate used for the IP, prior to treatment.
Project description:To assess the direct association of the nucleic acid binding protein yb-1 with mature microRNAs in breast cancer. To do this we performed immunoprecipitation (IP) of YB-1 protein to pull-down linked RNAs Two breast cancer cell-lines, representative of Luminal A and Basal molecular subtypes were used, MCF7 and MDA-MB-435S. An input control represents the RNA present in the lysate used for the IP, prior to treatment. IPs were performed in triplicates on different cell-lysates with one input control used as a representative of the RNA added to the IP reaction.
Project description:YB-1 controls epithelial-mesenchymal transitions by restricting translation of growth-related mRNAs and enabling expression of EMT-inducing transcription factors. We used microarrays to characterize the direct transcriptional and indirect translational regulation of mRNAs by exogenous YB-1 in breast cancer cell lines. Keywords: gene expression profiling
Project description:Background: Cancers are commonly characterised by hypoxia and also by global reductions in the levels of mature microRNAs. We have examined the hypothesis that hypoxia might mediate this reduction through repressive effects on microRNA biogenesis proteins. Methods: Breast cancer cell lines were exposed to hypoxia and manipulations of hypoxia inducible factor (HIF) and HIF hydroxylase activity. The effects of hypoxia on the mRNA and protein levels of enzymes involved in microRNA biogenesis (Dicer, Drosha, TARPB2, DCGR8, XPO5) was determined by RT PCR and immunoblotting. The effect of hypoxia on microRNAs was determined with microarray studies, RT PCR and reporter assays. Results: In breast cancer lines there was significant reduction of Dicer mRNA and protein levels in cells exposed to hypoxia. This effect was independent of HIF but dependent on the HIF hydroxylase PHD2 and was partly mediated by feedback effects via microRNAs. Furthermore, several other proteins with critical roles in microRNA biogenesis (Drosha, TARBP2 and DCGR8) also showed significant and co-ordinated repression under hypoxic conditions. Despite these substantial alterations no, or modest, changes were observed in mature microRNA production Conclusion: These observations provide further and important interfaces between oxygen availability and gene expression and a potential mechanistic explanation for the reduced levels of microRNAs observed in some cancers. They provide further support for the existence of feedback mechanisms in the regulation of the microRNA biogenesis pathway and the relative stability of microRNAs.
Project description:Long non-coding RNAs (lncRNA) have been identified as key regulators of tumorigenesis and development. We aim to explore the biological functions and molecular mechanisms of lncRNA MIR200CHG in breast cancer. We found that MIR200CHG is highly expressed in breast cancer tissues and is related to the tumor size and histopathological grade. In vitro and in vivo experiments confirmed that MIR200CHG can promote breast cancer proliferation, invasion, and drug resistance. MIR200CHG directly binds to the transcription factor Y-box binding protein-1 (YB-1), and inhibits its ubiquitination and degradation. MIR200CHG regulates YB-1 phosphorylation at serine 102, thereby affecting the expression of genes related to tumor cell proliferation, apoptosis, invasion, and drug resistance. Additionally, MIR200CHG partially affects the expression of miR-200c/141-3p encoded by its intron region. Therefore, MIR200CHG can promote the proliferation, invasion, and drug resistance of breast cancer by interacting with and stabilizing YB-1, and has the potential to become a target for breast cancer treatment.
Project description:YB-1 controls epithelial-mesenchymal transitions by restricting translation of growth-related mRNAs and enabling expression of EMT-inducing transcription factors. We used microarrays to characterize the direct transcriptional and indirect translational regulation of mRNAs by exogenous YB-1 in breast cancer cell lines. Keywords: gene expression profiling To evaluate this in a genome-wide manner we compared microarray expression profiles of total mRNA and mRNAs isolated from Ps (translationally active) or post-Ps (translationally inactive) fractions of MCF10AT-MSCV vs. MCF10AT-YB-1 cells