IL7R and acute lymphoblastic leukemia: T-ALL can be divided into molecular genetic subgroups which are characterized by unique gene expression signatures and aberrant activation of specific T-ALL transcription factor oncogenes, including MEF2C, HOXA, TLX1, NKX2.1, TLX3, TAL1, LMO1, and LMO2, and of oncogenic signaling cascades, including interleukin 7 receptor (IL7R), Janus kinase (JAK), signal transducer and activator of transcription (STAT) [3], phosphatidylinositol 3-kinase (PI3K)/Akt [4], and Ras/mitogen-extracellular signal-regulated kinase (MEK)/extracellular signal-regulated kinase (ERK) [5].