Talati et al.’s study revealed that Janus kinase 2 (JAK2) and the signal transducers and activators of transcription 5 (STAT5) A/B (JAK2-STAT5A/B) signaling pathway is involved in promoting the EMT phenotype and expression of the cancer stem cell maker BMI1 in prostate cancer cells. This evidence concerns the gene STAT5A and prostate cancer.