CD4 and T-cell non-Hodgkin lymphoma: To reveal whether STAT4 downregulation in mature T-cell neoplasms is a phenomenon specific to T-PLL, we re-analyzed published gene expression profiling (GEP) array data from different entities of mature T-cell lymphomas (TCL) compared to either pooled CD4+ or CD8+ T cells (Figure 4g) [25,26].