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The alterations induced in dendritic cells (DCs) in the cancer microenvironment have not been extensively explored. We found that the tumor-associated factor TGF-β may selectively upregulate the expression of miR-27a via the SP1 transcription factor. Importantly, miR-27a altered the activity of NF-κB and MAPKs (mitogen-activated protein kinases) p38, JNK (c-Jun N-terminal kinases) and ERK (extracellular signal-regulated kinase 1/2). It influences the production of proinflammatory cytokines by targeting TAB3, p38 MAPK, MAP2K4 and MAP2K7. As a consequence, miR-27a hampered the DC-mediated differentiation of Th1 and Th17 cells in vitro and in vivo, but it promoted the DC-mediated accumulation of Tr1 (CD4+IL-10+) and Treg (CD4+CD25+Foxp3+) cells in vivo. The repeated infusion of miR-27a-engineered DCs into tumor tissues accelerated tumor growth, indicating that miR-27a is a potential target for tumor immunotherapy. [ABSTRACT FROM AUTHOR]

Two recent genome-wide association studies of East Asian populations revealed three genetic variants in WDFY4/LRRC18 associated with systemic lupus erythematosus (SLE). To identify the gene contributing to this disease susceptibility, we examined the mRNA expression of WDFY4 and LRRC18 in patients with SLE and healthy controls. WDFY4 was significantly downregulated in SLE patients as compared with controls. We used allelic expression and dual-luciferase assays to identify the functional variant. Transcriptional activity was lower for the rs877819A than -G allele. Electrophoretic mobility shift and supershift assays revealed that the transcription factor Yinyang1 (YY1) binds to rs877819, with lower affinity to the A allele, which explained the reduced transcriptional activity. This effect was further confirmed by YY1 small interfering RNA knockdown, overexpression and chromatin immunoprecipitation experiments. rs877819 in WDFY4 might be the functional site associated with SLE by reduced binding of YY1 and downregulating WDFY4 expression. [ABSTRACT FROM AUTHOR]