Project description:This SuperSeries is composed of the following subset Series: GSE32488: Expression profiling of formalin-fixed, paraffin-embedded (FFPE) breast cancer metastases of the lymph node and autopsy tissues [DASL HT-12 samples] GSE32489: Expression profiling of formalin-fixed, paraffin-embedded (FFPE) breast cancer metastases of the lymph node and autopsy tissues [DASL HumanRef-v3 samples] Refer to individual Series
Project description:This SuperSeries is composed of the following subset Series: GSE23384: Gene profiling using archival formalin-fixed paraffin-embedded breast cancer specimens can generate informative microarray data: A comparison with matched fresh fine needle aspiration biopsy samples (FFPE samples) GSE23385: Gene profiling using archival formalin-fixed paraffin-embedded breast cancer specimens can generate informative microarray data: A comparison with matched fresh fine needle aspiration biopsy samples (FNA samples) Refer to individual Series
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that repress gene expression at the post transcriptional level via an antisense RNA-RNA interaction. Generally, miRNAs derived from snap frozen or fresh samples are used for array based profiling. Since tissues in most pathology departments are available only in formalin fixed and paraffin embedded state, we sought to evaluate the miRNA derived from formalin fixed and paraffin embedded (FFPE) samples for microarray analysis. In this study, miRNAs extracted from matched snap frozen and FFPE samples were profiled using the Agilent miRNA array platform. Each miRNA sample was hybridized to arrays containing probes interrogating 470 human miRNAs. A total of seven cases were compared in either duplicate or triplicate. Intrachip and interchip analyses demonstrated that the processes of miRNA extraction, labeling and hybridization from both frozen and FFPE samples are highly reproducible and add little variation to the results, as technical replicates showed high correlations (Kendall tau=0.722-0.853, Spearman rank correlation coefficient=0.891-0.954). Our results showed consistent high correlation between matched frozen and FFPE samples (Kendall tau=0.669-0.815, Spearman rank correlation coefficient=0.847-0.948), supporting the use of FFPE-derived miRNAs for profiling. Keywords: formalin-fixed and paraffin-embedded (FFPE) miRNA profiling
Project description:Analysis of 143 formalin-fixed, paraffin-embedded (FFPE) primary breast tumors using a Custom Breast Cancer Panel and Human Cancer Panel for the DASL platform. Molecular markers between the pathology defined subtypes of breast cancer were assessed to hypothesize potential therapeutic targets specific to the subtypes
