TGFB1 and idiopathic pulmonary fibrosis: For example, the downregulation of the Let-7, mir-29, and mir-30 families in idiopathic pulmonary fibrosis is related to the TGFβ pathway [54, 55], and mir-29 knockdown significantly upregulates TGFβ signaling in the induction of pulmonary fibrosis [54].