Abstract 1479: Differential expression of microRNAs in transformation of follicular lymphoma to diffuse large B cell lymphoma

MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression, and are frequently aberrantly expressed in cancer. We aimed to understand their role in the transformation of indolent follicular lymphoma (FL) into an aggressive diffuse large B cell lymphoma. This happens in ~3% of cases per year during the course of the disease, and is associated with median survival of only 2 years. The NGS revealed number of aberrations associated with transformed FL (tFL), including frequent high-level activity of MYC (amplifications, translocations, and mutations) or loss of DNA damage regulators (p53, CDKN2A/B). Firstly, we performed a miRNA profiling (TaqMan miRNA Arrays) in paired FL and tFL samples (N=8 pairs). This revealed a relatively small group of 5 miRNAs that are consistently differentially expressed in tFL (P 1.5). Since the most frequently acquired aberration in tFL is the high-level activity of MYC we performed a correlation analysis of MYC levels and expression of these miRNAs in additional samples of FL, tFL, and CLL samples with/without MYC duplication (N=40 FL/tFL, N=39 CLL). This revealed that at least one of these miRNAs is significantly down-modulated (P Citation Format: Katerina Musilova, Gabriela Pavlasova, Vaclav Seda, Eva Vojackova, Katerina Cerna, Veronika Svobodova, Robert Pytlik, Vit Prochazka, Zuzana Prouzova, Sarka Pospisilova, Lenka Zlamalikova, Heidi Mocikova, Lenka Kruzova, Marie Jarosova, Andrew Evans, Clive Zent, Leos Kren, Marek Trneny, Jiri Mayer, Andrea Janikova, Marek Mraz. Differential expression of microRNAs in transformation of follicular lymphoma to diffuse large B cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1479. doi:10.1158/1538-7445.AM2017-1479