MicroRNAs as B-cell lymphoma biomarkers

B-cell lymphomas represent a group of more than 35 recognized mature B-cell neoplasms differentiated largely on the basis of immunohistochemical staining patterns that are often challenging to accurately diagnose. Despite having been only formally recognized just over 10 years ago, microRNAs (miRNAs) have become one of the trendiest topics in biology. Dysregulation of miRNAs is a ubiquitous feature of cancer in general, including B-cell lymphomas. Many of the miRNAs aberrantly expressed in B-cell lymphomas also play a crucial regulatory role in normal hematopoietic function. MiRNAs show great potential as novel biomarkers of cancer, as they can differentiate cancers according to diagnosis and developmental stage, even discriminating between cancers that are poorly separated histologically. Furthermore, they can be robustly measured from routinely prepared formalin-fixed paraffin-embedded biopsy material and biological fluids such as blood. Here, we consider the identity, function, and biomarker potential of miRNAs in B-cell lymphomas and, most importantly, the hurdles that remain to be overcome if they are really to become part of future clinical practice.