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MicroRNAs (miRNAs) and heterogeneous nuclear ribonucleoproteins (hnRNPs) are families of sequence-specific, posttranscriptional modulators of gene expression. Despite extensive mechanistic and functional studies on both regulatory classes, the interactions and crosstalk between them are largely unexplored. We have reported that competition between miR-297 and hnRNP L to bind a 3΄UTR-localized CA-rich element (CARE) of VEGFA mRNA regulates its translation. Here, we show that translation of VEGFA mRNA in human myeloid cells is dictated by a bi-directional interaction between miR-574-3p, a CA-rich microRNA, and hnRNP L. In normoxia, miR-574-3p, acting as a decoy, binds cytoplasmic hnRNP L and prevents its binding to the CARE and stimulation of VEGFA mRNA translation, simultaneously permitting miR-297-mediated translational silencing. However, in hypoxia, cytoplasmic …