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Status |
Public on Jun 09, 2010 |
Title |
Saline 1 vs. miR-122 antagomir, mouse 1, mouse liver, 1 month |
Sample type |
RNA |
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|
Channel 1 |
Source name |
liver
|
Organism |
Mus musculus |
Characteristics |
agent: Saline tissue: liver
|
Extracted molecule |
total RNA |
Extraction protocol |
Qiagen RNeasy spin columns with DNAse treatment
|
Label |
Cy3
|
Label protocol |
custom automated version of the aminoallyl MessageAmp II kit from Ambion.
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|
|
Channel 2 |
Source name |
liver
|
Organism |
Mus musculus |
Characteristics |
conditions: miR-122 antagomir, mouse 1, mouse liver, 1 month agent: miR-122 antagomir time: 1 month tissue: liver
|
Extracted molecule |
total RNA |
Extraction protocol |
Qiagen RNeasy spin columns with DNAse treatment
|
Label |
Cy5
|
Label protocol |
custom automated version of the aminoallyl MessageAmp II kit from Ambion.
|
|
|
|
Hybridization protocol |
Microarrays are incubated at 40°C for 48 hours in a rotating carousel. Hybridizations to custom Agilent microarrays are completed as previously described (Hughes et al.Nat Biotech (2001), 19(4):342-7). Microarrays are washed to remove non-specific hybridized sample. Afterwards, microarrays are dried in an ozone-free nitrogen chamber.
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Scan protocol |
Microarrays are scanned using the Agilent LP2 laser scanner. The scanner output is a Tiff file, which contains the quantitative hybridization data from each individual microarray. The Tiff files are then processed using Rosetta custom feature extraction software.
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Description |
Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths worldwide, reflecting the need for a better understanding of hepatocarcinogenesis. In this study, we examined the genome-wide expression profiles of both miRNAs and mRNAs from paired tumor and adjacent non-tumor tissues from a cohort of 96 HCC patients in Hong Kong where hepatitis B virus (HBV) is endemic. The comprehensive analysis of the coordinate expression of miRNAs and mRNAs reveals that miR-122 is under-expressed in HCC and that it is an important regulator for normal mitochondrial metabolism. A decreased level of miR-122 leads to an increase in expression of miR-122 seed-matched genes, a loss of mitochondrial metabolic function, and a decrease in the expression of many miR-122 secondary targets. These secondary targets are prognostic markers for HCC patients. Transcriptome profiling data from an additional 180 HCC and 40 liver cirrhotic patients in the same cohort were used to confirm the anti-correlation of miR-122 primary and secondary target gene sets. To test the HCC findings in normal mouse liver, we used an antagomir against miR-122 and identified altered gene expression profiling by microarray analysis in mouse in vivo experiments. The mouse data recapitulated the human HCC findings. Our anti-miR122 data further provided a direct link between increases in the mRNA levels of miR-122 controlled genes and impairments of mitochondrial metabolism. In summary, we find miR-122 loss may be detrimental to mitochondrial-related metabolisms in sustaining critical liver function and contribute to the morbidity and mortality of liver cancer patients.
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Data processing |
Data were processed using the Rosetta Resolver® system. Rosetta's custom feature extraction software performs error modeling before data are loaded into the Resolver system. The Resolver system performs a squeeze operation that combines replicates of the same sequence in an array while applying error weighting. The error weighting consists of adjusting for additive and multiplicative noise. A P-value is generated and propagated throughout the system. The P-value represents the probability that a gene is expressed. The Resolver system allows users to set thresholds, below which genes of a P-value are considered to be significantly expressed. The Resolver system also combines multiple arrays using a squeezing process. If multiple spots reference one sequence, summarization is performed using an error-weighted average as described in Roland Stoughton and Hongyue Dai, Statistical Combining of Cell Expression Profiles. US Patent #6,351,712, February 26, 2002.
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Submission date |
May 28, 2010 |
Last update date |
Jun 08, 2010 |
Contact name |
Julja Burchard |
Organization name |
Merck & Co., Inc.
|
Department |
Computational & Systems Biology
|
Street address |
33 Avenue Louis Pasteur
|
City |
Boston |
State/province |
MA |
ZIP/Postal code |
02176 |
Country |
USA |
|
|
Platform ID |
GPL9733 |
Series (1) |
GSE22058 |
miR-122 as a Regulator of Mitochondrial Metabolic Gene Network in Hepatocellular Carcinoma |
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