Vodobatinib overcomes cancer multidrug resistance by attenuating the drug efflux function of ABCB1 and ABCG2

Multidrug resistance (MDR) remains a significant obstacle in cancer treatment, primarily attributable to the overexpression of ATP-binding cassette (ABC) transporters such as ABCB1 and ABCG2 within cancer cells. These transporters actively diminish the effectiveness of cytotoxic drugs by facilitating ATP hydrolysis-dependent drug efflux, thereby reducing intracellular drug accumulation. Given the absence of approved treatments for multidrug-resistant cancers and the established benefits of combining tyrosine kinase inhibitors (TKIs) with conventional anticancer drugs, we investigate the potential of vodobatinib, a potent c-Abl TKI presently in clinical trials, to restore sensitivity to chemotherapeutic agents in multidrug-resistant cancer cells overexpressing ABCB1 and ABCG2. Results indicate that vodobatinib, administered at sub-toxic concentrations, effectively restores the sensitivity of multidrug-resistant cancer cells to cytotoxic drugs in a concentration-dependent manner. Moreover, vodobatinib enhances drug-induced apoptosis in these cells by inhibiting the drug-efflux function of ABCB1 and ABCG2, while maintaining their expression levels. Moreover, we found that while vodobatinib enhances the ATPase activity of ABCB1 and ABCG2, the overexpression of these transporters does not induce resistance to vodobatinib. These results strongly suggest that increased levels of ABCB1 or ABCG2 are unlikely to play a significant role in the development of resistance to vodobatinib in cancer patients. Overall, our findings unveil an additional pharmacological facet of vodobatinib against ABCB1 and ABCG2 activity, suggesting its potential incorporation into combination therapy for a specific subset of patients with tumors characterized by high ABCB1 or ABCG2 levels. Further investigation is warranted to fully elucidate the clinical implications of this therapeutic approach.