PIK3CA and testicular germ cell tumor: Taken together, these results indicate that the study of the testicular secretome of TGCT patients could be a useful tool to identify the possible interaction among PI3K inhibitors, i.e., those used for the targeted therapy proposed by [26] Selfe and coworkers, and the signaling pathways simultaneously present in the testicular niche that can modulate the effect of the inhibitors, leading to paradoxical effects.