REN and neoplasm: Importantly, the observed treatment response in the third case indicates a dual potential mechanism: first, the reduction in tumor burden removes the antigenic stimulus; second, angiotensin receptor blockers (ARBs) may exert nephroprotective and potential antitumor effects by inhibiting the renin–angiotensin–aldosterone system (RAAS), which has been implicated in tumorigenesis via signaling pathways including Ras/RAF/MAPK/ERK, PI3K/AKT/mTOR, and Wnt/β-catenin (56–61).