For example, piR-25783 activates the TGF-β/Smad2/Smad3 pathway in fibroblasts by increasing Smad2 and Smad3 phosphorylation, promoting the fibroblast-to-myofibroblast transition (FMT) process and enhancing the proliferative and metastatic properties of tumor cells [115]. Here, PIR is linked to neoplasm.