MAPK3 and neoplasm: Overall, it appears that PSMA signaling may be involved at multiple stages of the LNCaP cell deregulation and possibly also of in vivo tumorigenesis, because 1) increased ERK1/2 activation correlates with increasing Gleason score and advanced tumor stage [31], and 2) increased activation of STAT 5 has been observed “in vivo” in 65% of human prostate cancers, being associated with high histological grade and being a predictor of early disease recurrence [29], [30], [32].