In this chapter, we summarize the current knowledge on microRNA (miRNA) expression, function and putative clinical value in Hodgkin’s lymphoma (HL). HL is the second most common lymphoma subtype, and mainly affects young adults or elderly. Malignant cells in HL are scarce, usually less than 1%, and these cells are of B-cell origin. As miRNAs are involved in almost all known biological processes, deregulation of miRNAs is thought to play an important role in the pathogenesis of HL. MiRNA expression studies have been performed on HL cell lines,...

Immune cell-type specific miRNA expression patterns have been described but the detailed role of single miRNAs in the function of T-cells remains largely unknown. We investigated the role of miR-21 in the function of primary human CD4+ T-cells. MiR-21 is substantially expressed in T-cells with a memory phenotype, and is robustly upregulated upon alpha CD3/CD28 activation of both naive and memory T-cells. By inhibiting the endogenous miR-21 function in activated naive and memory T-cells, we showed that miR-21 regulates fundamentally different aspects of T-cell biology, depending on the...

Processing of miRNAs occurs simultaneous with the transcription and splicing of their primary transcripts. For the small subset of exonic miRNAs it is unclear if the unspliced and/or spliced transcripts are used for miRNA biogenesis. We assessed endogenous levels and cellular location of primary transcripts of three exonic miRNAs. The ratio between unspliced and spliced transcripts varied markedly, i.e. >1 for BIC,