The invention provides various methods for classifying prostate cancers into subtypes. The classification methods may be used to diagnose or prognose prostate cancers. In one embodiment, the subtypes are PCS1, PCS2, or PCS3. In one embodiment, the PCS1 subtype is most likely to progress to metastatic disease or prostate cancer specific mortality when compared to the PCS2 subtype or PCS3 subtype. In one embodiment, the PCS1 subtype is resistant to enzalutamide.
