ABCB1 and lung cancer: Together with coleon U (1) and coleon U-quinone (2), 8α,9α-epoxycoleon U-quinone (3) was also found in C. mutabilis leaves and compounds (1–3) were shown to inhibit P-glycoprotein (P-gp) activity in lung cancer cell line (Ntungwe et al., 2022).