TGFB1 and prostate cancer: The prostate cancer pathway, ERK/MAPK signaling, and TGF-β signaling are well-studied in PCa metastasis, and we found that most of the targets of identified microRNA biomarkers were the key components of these pathways, meanwhile, some tumor suppressor genes, e.g., PTEN and p27, were regulated by the identified microRNAs.