SMAD2 and lung cancer: On the other hand, miR-93 influences the UPS by decreasing the neural precursor cell expressed developmentally downregulated gene 4-like (NEDD4L), an E3 ubiquitin ligase, which inhibits transforming growth factor beta (TGFβ) signaling in lung cancer cells by marking the mothers against decapentaplegic homolog 2/3 (SMAD2/3) proteins for proteasomal degradation.