Differentiating between cancer and normal tissue samples using multi-hit combinations of genetic mutations.
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ABSTRACT:
SUBMITTER: Dash S
PROVIDER: S-EPMC6353925 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Tumor associated miRNAs in hereditary breast cancer. In this study we investigated the role of miRNAs in hereditary breast tumors comparing with normal breast tissue. Global miRNA expression profiling was performed on 22 hereditary breast tumors and 15 non-tumoral breast tissues. We identified 19 miRNAs differentially expressed, most of them down-regulated in tumors. An important proportion of deregulated miRNAs in hereditary tumors were previously identified commonly deregulated in sporadic breast tumors. Our results identify miRNAs associated to hereditary breast cancer, as well as miRNAs commonly miss-expressed in hereditary and sporadic tumors, suggesting common underlying mechanisms of tumor progression. In addition, we provide evidence that KRAS is a target of miR-30c, and that this miRNA suppresses breast cancer cell growth potentially through inhibition of KRAS signaling.
2013-12-01 | GSE32922 | GEO
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2013-12-01 | E-GEOD-32922 | biostudies-arrayexpress
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Project description:we combined their genome-wide profiles of tumors and normal adjacent tissues in 10 ccRCC patients. The results showed that 283 miRNAs were down-regulated and 187 up-regulated, meanwhile 7473 mRNAs were up-regulated and 3439 down-regulated in ccRCC. Expressions of 12 miRNAs and genes were validated in 10 patients we studied by RT-qPCR (validation rate from 60% to 100%). Differentially expressed gene analysis showed the collective change of miR-200 and SLC22A gene family, and pathway analysis revealed down-regulation of multiple metabolic pathways and up-regulation of focal adhesion, ECM-receptor interaction, etc. Moreover, A miRNA cluster located in chromosome Xq27.3 were significantly down-regulated in ccRCC, which were verified in 53 ccRCC patients by RT-qPCR (validation rate from 63.8% to 88.6%).56 and 586 potentially novel miRNAs and mRNA we detected according to statistical analyses. In addition, 14 miRNA candidates were randomly selected to validate using qRT-PCR and Sanger sequcencing technology, 10 of out 14 could be successfully amplified,.Plus, the sequences of all 5 randomly selected amplified products were confirmed by cloned Sanger sequencing.Our data demonstrated a combined profiling of miRNAs and mRNAs in ccRCC, which showed the decreased metabolism and the perturbation of renal cell function. Moreover, this study identified the expression alteration of a miRNA cluster on Xq27.3, which suggested its potential function in carcinogenesis of ccRCC
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