Project description:MiR-1287-5p has inhibitory effects on breast cancer growth mediated by interaction with phosphoinositide 3-kinase CB (miR-1287-5p overexpression study)
Project description:Background: Non-coding RNAs and especially microRNAs have been discovered as master regulators of cancer initiation and progression. The aim of our study was to discover and characterize the function of yet uncharacterized microRNAs in human breast carcinogenesis. Methods: In an unbiased approach, we made use of a commonly used model system for breast cancer (BC) stem cells (“mammospheres”) to identify whole miRNome alterations with a special focus on previously uncharacterized miRNAs in BC. We further characterized the influence of microRNA-1287-5p, a yet uncharacterized microRNA in BC, in patient samples (n=1262) and on several hallmarks of cancer in vitro and in vivo with a special focus on triple negative BC. The molecular mode of action was further characterized using whole transcriptome analysis, in silico prediction tools, miRNA-interaction luciferase assays and pheno-copy assays. Results: We identified miR-1287-5p among many others as differentially expressed in mammospheres. Clinical validation indicated that miR-1287-5p is significantly downregulated in human BC and associated with poor prognosis. This clinical finding can be explained by miR-1287-5p mediated growth inhibitory effects, G1 cell cycle arrest, decreased anchorage-independent growth and tumor growth in vivo. Finally, we identified PIK3CB as a direct molecular interactor of miR-1287-5p and a pheno-copy factor for miR-1287-5p. Finally, targeting PI3K-signaling pathway with chemical inhibitors together with miR-1287-5p mimics increased the pharmacological growth inhibitory potential. Conclusion: In conclusion, our data identified for the first time an involvement of miR-1287-5p in human BC and suggest a potential for therapeutic interventions in hardly to treat triple negative BC.
Project description:Background: Non-coding RNAs and especially microRNAs have been discovered as master regulators of cancer initiation and progression. The aim of our study was to discover and characterize the function of yet uncharacterized microRNAs in human breast carcinogenesis. Methods: In an unbiased approach, we made use of a commonly used model system for breast cancer (BC) stem cells (“mammospheres”) to identify whole miRNome alterations with a special focus on previously uncharacterized miRNAs in BC. We further characterized the influence of microRNA-1287-5p, a yet uncharacterized microRNA in BC, in patient samples (n=1262) and on several hallmarks of cancer in vitro and in vivo with a special focus on triple negative BC. The molecular mode of action was further characterized using whole transcriptome analysis, in silico prediction tools, miRNA-interaction luciferase assays and pheno-copy assays. Results: We identified miR-1287-5p among many others as differentially expressed in mammospheres. Clinical validation indicated that miR-1287-5p is significantly downregulated in human BC and associated with poor prognosis. This clinical finding can be explained by miR-1287-5p mediated growth inhibitory effects, G1 cell cycle arrest, decreased anchorage-independent growth and tumor growth in vivo. Finally, we identified PIK3CB as a direct molecular interactor of miR-1287-5p and a pheno-copy factor for miR-1287-5p. Finally, targeting PI3K-signaling pathway with chemical inhibitors together with miR-1287-5p mimics increased the pharmacological growth inhibitory potential. Conclusion: In conclusion, our data identified for the first time an involvement of miR-1287-5p in human BC and suggest a potential for therapeutic interventions in hardly to treat triple negative BC.
Project description:Breast Cancer is the cancer with most incidence and mortality in women. microRNAs are emerging as novel prognosis/diagnostic tools. Our aim was to identify a serum microRNA signature useful to predict cancer development. We focused on studying the expression levels of 30 microRNAs in the serum of 96 breast cancer patients versus 92 control individuals. Bioinformatic studies provide a microRNA signature, designated as a predictor, based upon the expression levels of 5 microRNAs. Then, we tested the predictor in a group of 60 randomly chosen women. Lastly, a proteomic study unveiled the over-expression and down-regulation of proteins differently expressed in the serum of breast cancer patients versus that of control individuals. Twenty-six microRNAs differentiate cancer tissue from healthy tissue and 16 microRNAs differentiate the serum of cancer patients from that of the control group. The tissue expression of miR-99a-5p, mir-497-5p, miR-362, and miR-1274, and the serum levels of miR-141 correlated with patient survival. Moreover, the predictor consisting of mir-125b-5p, miR-29c-3p, mir-16-5p, miR-1260, and miR-451a was able to differentiate breast cancer patients from controls. The predictor was validated in 20 new cases of breast cancer patients and tested in 60 volunteer women, assigning 11 out of 60 women to the cancer group. An association of low levels of mir-16-5p with a high content of CD44 protein in serum was found. Circulating microRNAs in serum can represent biomarkers for cancer prediction. Their clinical relevance and use of the predictor here described might be of potential importance for breast cancer prediction.
Project description:MiRNAs have been shown to alter both protein expression and secretion in different cellular contexts. By combining in vitro, in vivo and in silico techniques, we demonstrated that overexpression of pre-miR-1307 reduced the ability of breast cancer cells to induce endothelial cell sprouting and angiogenesis. However, the molecular mechanism behind this and the effect of the individual mature miRNAs derived from pre-miR-1307 on protein secretion and is largely unknown. Here, we overexpressed miR-1307-3p|0, -3p|1 and 5p|0 in MDA-MB-231 breast cancer cells and assessed the impact of miRNA overexpression on protein secretion by Mass Spectrometry. Unsupervised hierarchical clustering revealed a distinct phenotype induced by overexpression of miR-1307-5p|0 compared to the controls and to the 5’isomiRs derived from the 3p-arm. Together, our results suggest different impacts of miR-1307-3p and miR-1307-5p on protein secretion which is in line with our in vitro observation that miR-1307-5p, but not the isomiRs derived from the 3p-arm reduce endothelial cell sprouting in vitro. Hence these data support the hypothesis that miR-1307-5p is at least partly responsible for impaired vasculature in tumors overexpressing pre-miR-1307.
Project description:Oxidative stress is an important environmental exposure associated with psychiatric disorders, but the underlying molecular mechanisms remain elusive. We recently observed enrichment of neurodevelopmental processes and diseases among a large number of differentially expressed genes during or after exposure to oxidative stress in an in vitro model of neuronal differentiation. To further explore the regulatory mechanisms that might account for a coordinated response to this exposure, we investigated changes in the expression of small non-coding miRNA in this system and estimated their interaction with differentially expressed mRNA. These molecules are thought to play a crucial role in brain development and its response to stress. Here we observed more than a hundred differentially expressed miRNAs, including 72 previously reported to be dysregulated in psychiatric disorders. The 7 most influential miRNAs associated with pre-treatment exposure were miR-138-5p, miR-96-5p, miR-34c-5p, miR-1287-5p, miR-497-5p, miR-195-5p, and miR-16-5p. These were sup-ported by at least 10 negatively correlated mRNA connections, and formed hubs in interaction network with 134 genes enriched with neurobiological function. Whereas in the co-treatment con-dition, miRNA-mRNA interaction pairs were enriched not only in neuronal processes, but also in cardiovascular and immunity-related disease ontologies. Interestingly, 12 differentially expressed miRNAs originated from the same genomic location, DLK1-DIO3, which encodes a schizophre-nia-associated miRNA signature. Collectively, these findings suggest that early exposure to oxida-tive stress, before and during prenatal neuronal differentiation, might increase the risk of mental illnesses in adulthood by disturbing the expression of miRNAs that regulate neurodevelopmental-ly significant genes and networks.
Project description:For deep understading of miR-1285-5p in breast cancer, we have employed whole genome microarray expression profilings as a discovery platform to identify target genes of miR-1285-5p. Using human breast cancer cell lines (MCF7, MDA-MB-231, HCC1937 and HCC1954), 31 down-down regulated genes were identified by overexpression of miR-1285-5p reagardless of tumor biology. Functional interaction of miR-1285-5p with two genes (TMEM194A and SLC30A9) from this gene sets was evaluated by r-rt-PCR, Western blot and luciferase transporter assay.
Project description:The objective of these experiments is to identify novel direct and indirect targets of miR-150-5p in breast cancer cell lines. The goal is that these will give direction as to what targets or pathways may be contributing to the reduced growth observed in these cell lines upon restoration of miR-150-5p. A therapy directed towards one or more critical subtype-specific targets could be developed as a therapeutic for breast cancer patients. Using has-miR-150-5p mirVana miRNA mimic (Ambion, 4464066), miR-150-5p was restored to a triple negative breast cancer cell line, BT-549.
Project description:The objective of these experiments is to identify novel direct and indirect targets of miR-150-5p in breast cancer cell lines. The goal is that these will give direction as to what targets or pathways may be contributing to the reduced growth observed in these cell lines upon restoration of miR-150-5p. A therapy directed towards one or more critical subtype-specific targets could be developed as a therapeutic for breast cancer patients. Using has-miR-150-5p mirVana miRNA mimic (Ambion, 4464066), miR-150-5p was restored to an estrogen receptor positive breast cancer cell line, ZR-75-1.
Project description:microRNA (miRNA) dysfunction is associated with a variety of human diseases including cancer. Our previous study showed that miR-671-5p was deregulated during breast cancer progression. We aim to decipher the functional mechanism of miR- 671-5p in breast cancer. We used microarrays to detail the global programme of gene expression after overexpression miR-671-5p in several breast cancer cell lines, and those altered genes might potentially under regulation of miR-671-5p contibuting to breast cancer developemtn. miR-671-5p or scramble control nucleotide were tranfected into breast cancer cell lines, including MCF7, MDA231 and SKBR3. Total RNA were extracted and hybridized on Affymetrix microarrays. We sought to identify the potential downstream target genes that under miR-671-5p regulation by overexpress miR-671-5p. Potential targets were predicted to see if it has binding sites matching miR-671-5p sequence by miRNA target prediction softwares.