In melanoma, Pan et al. demonstrated that cleistanthin A (CA), a natural compound which has the ability to inhibit v-ATPase activity and to neutralize the pH of lysosomes, inhibited the invasion and migration of human melanoma A375 cells in vitro by downregulating the expression of matrix metallopeptidase (MMP)-2 and -9 [69]. Here, MMP2 is linked to melanoma.