Despite decades of considerable efforts, numerous ABCB1 inhibitors have been shown to significantly increase the efficacy of certain anticancer drugs in MDR tumor cells in vitro and in vivo, but no ABCB1 inhibitors have been approved for clinical use due to the lack of significant clinical efficacy or safety concerns (Bissett et al., 1991; Jackson et al., 2020). Here, ABCB1 is linked to neoplasm.