The activity of several Hsp90 proteins, including HIF-1α, α-SMA and p-p38, all of which are important modulators in critical physiological processes such as cell proliferation, migration and invasion [50], is also modulated by CPS1-IT1, which may explain why melatonin is involved in regulating a diverse range of cellular physiological processes (including aging) and exerts anti-cancer effects. Here, HIF1A is linked to cancer.