IL1B and renal fibrosis: Previous study shows that macrophage‐derived circular RNA ACTR2 (circACTR2) mediates EMT of tubular epithelial cells in a paracrine manner through the production of IL‐1β in renal fibrosis.[49] EndoMT is another way to generate myofibroblast, which plays an important role in fibrosis‐related diseases.