Gene signatures of testicular seminoma with emphasis on expression of ets variant gene 4.

Gene expression patterns of testicular seminoma were analysed applying oligonucleotide microarrays in 40 specimens of different tumour stages (pT1, pT2, pT3) and in normal testes. Transcripts of maternally expressed 3 transcripts were expressed in seminoma without correlation with delta-like 1 homologue expression indicating an impaired imprinting status in seminoma. Interestingly, the transcripts of bromodomain-containing 2 and nuclear autoantigenic sperm protein associated with spermatogenesis were significantly upregulated in progressing tumour stages.

Differential expression of IGF components and insulin receptor isoforms in human seminoma versus normal testicular tissue.

Insulin-like growth factors (IGF) have mitogenic and antiapoptotic functions, and may be involved in tumor growth. The purpose of the study was to investigate the role of IGF components in seminoma compared to normal testis. Normal testicular tissues from autopsy cases and seminoma from surgery cases were obtained for microarray and real-time reverse transcription polymerase chain reaction (RT-PCR) analysis of IGF-1, IGF-2, IGF receptor type 1 (IGF-R1), IGF-R2, insulin receptor isoforms A (IR-A) and B (IR-B), and IGF-binding proteins (IGFBP) 1-6.

Standardization strategy for quantitative PCR in human seminoma and normal testis.

Housekeeping genes are commonly used as endogenous references in quantitative RT-PCR. Ideally these genes are constitutionally expressed by all cell types and do not vary under experimental conditions. Tissues of 9 normal testes and 22 classical pure seminoma were obtained for RNA-extraction.

Determination of stable housekeeping genes, differentially regulated target genes and sample integrity: BestKeeper--Excel-based tool using pair-wise correlations.

The stability of standard gene expression is an elementary prerequisite for internal standardisation of target gene expression data and many so called housekeeping genes with assumed stable expression can exhibit either up- or down-regulation under some experimental conditions. The developed, and herein presented, software called BestKeeper determines the best suited standards, out of ten candidates, and combines them into an index. The index can be compared with further ten target genes to decide, whether they are differentially expressed under an applied treatment.