Gene Expression Profiling of Human Pediatric Astrocytomas
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Jane Engler
PROVIDER: E-GEOD-38330 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:Pediatric astrocytomas, a leading cause of death associated with cancer, are the most common primary central nervous system tumors found in children. Most studies of these tumors focus on adults, not children. We examined the global protein and microRNAs expression pattern by 2D SDS-PAGE, mass spectrometry (MALDI-TOF) and RT2 miRNA PCR Array System. MicroRNAs analysis revealed for the first time novel microRNAs involved in astrocytomas biology. Interestingly, miR-138 and miR-145 down-regulation appear to be associated with protein over-expression of vimentin and Bax, respectively. In conclusion, our results show that novel proteins and microRNAs altered on pediatric astrocytoma could serve as biomarkers to distinguish between astrocytoma grades. Astrocytoma samples were colected from patients and total RNA isolation (30 mg of tissue) was performed using the TRIzol® protocol (Invitrogen, USA) according to the manufacturer′s instructions. Samples were analyzed using SA Biosciences RT2 miRNA PCRArray System to determied the miRNA expression between control samples and tumors
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Project description:We have used microarray comparative genomic hybridization (aCGH) at 1Mb resolution to study copy number changes in a series of WHO Grade II Astrocytomas (n=21). We have used Illumina arrays to study genome-wide expression patterns in a series of WHO Grade II Astrocytomas (n=10). Keywords: Array Comparative Genomic Hybridization (aCGH), Expression microarray [aCGH]: Single hybridization per case. 21 astrocytomas WHO grade II were analyzed. Target (tumor) labelled with Cy5 and reference with Cy3. Mixture of 20 normal male or female genomic DNA was used in sex-mismatched hybridization. [mRNA]: Single hybridization per case. 10 astrocytomas WHO grade II were analyzed (5 adult, 5 pediatric)
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