Unknown,Transcriptomics,Genomics,Proteomics

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Transcription profiling of repeatedly thaw-frozen ovarian tumour samples

ABSTRACT: We evaluated the influence of repeatedly division of tumour samples at room temperature on gene expression profile. Experimental Design: four old (more than five years) ovarian tumour samples were divided twice on two different days giving a total of three aliquots each. RNA from the removed tissue aliquot was extracted and purified at the day of division and the remaining tissue re-frozen. The Trizol reagent kit and RNeasy MinElute kit were used for RNA extraction and purification. RNA quantity was evaluated on a spectrophotometer and quality was evaluated on the Agilent Bioanalyzer 2100. RNA from all three aliquots of the four old tumour samples were labeled with the ENZO kit and hybridized to twelve Affymetrix chips U133A 2.0. The four tumours were named 2, 3, 4 and 7. Aliquots from the first day are called "a", from the second day "b", the third day "c".

ORGANISM(S): Homo sapiens

SUBMITTER: Kirsten Jochumsen

PROVIDER: E-MEXP-398 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

RNA quality and gene expression analysis of ovarian tumor tissue undergoing repeated thaw-freezing.

Jochumsen Kirsten Marie KM Tan Qihua Q Dahlgaard Jesper J Kruse Torben A TA Mogensen Ole O

Experimental and molecular pathology 20060713 1

Gene expression profiles evaluated by microarray-based quantization of RNA are used in studies of differential diagnosis and prognosis in cancer. RNA of good quality is mandatory for this evaluation. The RNA most often comes from tumor banks with limited amount of tissue, and the tissue often undergoes repeated thawing and freezing. We evaluated the influence of repeated division of tumor samples at room temperature, on RNA quality and quantity, in addition to the gene expression profile. Sixtee ...[more]

PMID: 16842777

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Dataset Information

Transcription profiling of repeatedly thaw-frozen ovarian tumour samples

Publications

RNA quality and gene expression analysis of ovarian tumor tissue undergoing repeated thaw-freezing.

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