PTEN and breast cancer: In addition, it has been revealed that BC cell-derived exosomal miRNA-200b-3p could target the 3'-UTR of tumor suppressor-phosphatase and Tensin homolog (PTEN) and inhibit their synthesis, activating the protein kinase B (AKT)/nuclear factor kappa-B (NF-κB) pathway and leading to the secretion of the C-C patterned chemokine ligand 2 (CCL2) 25.