Gene expression profiling using formalin-fixed paraffin-embedded primary specimens of AIDS-related Lymphomas

Background Gene expression profiling has been useful for classification and prognostication of a variety of hematologic neoplasms occurring in the general population. This type of analysis of AIDS related lymphomas (ARLs) has been limited because of their rarity, heterogeneity and lack of frozen tissue for analysis, with the largest studies including 25 cases (Klein et al., Blood 2003, Deffenbacher et al., J AIDS 2010). To overcome this limitation, we employed a cDNAbased microarray technology, DNA-mediated Annealing, Selection, Ligation and Extension (DASL) for the analysis of formalin-fixed paraffin-embedded (FFPE) archival samples, allowing us to perform gene expression analysis of the largest cohort of ARLs thus far.