JDP2 - an Oncogenic bZIP Transcription Factor in T-cell Acute Lymphoblastic Leukemia [RNA-Seq]

A substantial subset of patients with T-cell acute lymphoblastic leukemia (T-ALL) develops resistance to steroids and succumb to their disease. JDP2 encodes a bZIP protein that has been implicated as a T-ALL oncogene from insertional mutagenesis studies in mice, but its role in human T-ALL pathogenesis has remained obscure. Here we show JDP2 is aberrantly expressed in a subset of T-ALL patients and is associated with poor survival. JDP2 is required for T-ALL cell survival, as its depletion by shRNA knockdown leads to apoptosis. Mechanistically, JDP2 regulates pro-survival signaling through direct transcriptional regulation of MCL1. Furthermore, JDP2 is one of few oncogenes capable of initiating T-ALL in transgenic zebrafish. Notably, thymocytes from rag2:jdp2 transgenic zebrafish express high levels of mcl1, and demonstrate resistance to steroids in vivo. These studies establish JDP2 as a novel oncogene in high-risk T-ALL, and implicate overexpression of MCL1 as a mechanism of steroid resistance in JDP2-overexpressing cells. RNA-seq in T-ALL cells with and without short hairpins against JDP2