Genetic deficiency or pharmacological inhibition of OCT3 with nilotinib significantly preserved cardiovascular function and reduced doxorubicin-induced cardiac injury in mice without compromising antitumor efficacy.
Does genetic or pharmacological inhibition of OCT3 prevent doxorubicin-induced cardiac injury in preclinical models?
Targeting the OCT3 transporter genetically or pharmacologically with nilotinib attenuates doxorubicin-induced cardiotoxicity by reducing its cardiac accumulation.
p-value: p=<0.05
Doxorubicin is a commonly used anticancer agent that can cause debilitating and irreversible cardiac injury. The initiating mechanisms contributing to this side effect remain unknown, and current preventative strategies offer only modest protection. Using stem-cell-derived cardiomyocytes from patients receiving doxorubicin, we probed the transcriptomic landscape of solute carriers and identified organic cation transporter 3 (OCT3) (SLC22A3) as a critical transporter regulating the cardiac accumulation of doxorubicin. Functional validation studies in heterologous overexpression models confirmed that doxorubicin is transported into cardiomyocytes by OCT3 and that deficiency of OCT3 protected mice from acute and chronic doxorubicin-related changes in cardiovascular function and genetic pathways associated with cardiac damage. To provide proof-of-principle and demonstrate translational relevance of this transport mechanism, we identified several pharmacological inhibitors of OCT3, including nilotinib, and found that pharmacological targeting of OCT3 can also preserve cardiovascular function following treatment with doxorubicin without affecting its plasma levels or antitumor effects in multiple models of leukemia and breast cancer. Finally, we identified a previously unrecognized, OCT3-dependent pathway of doxorubicin-induced cardiotoxicity that results in a downstream signaling cascade involving the calcium-binding proteins S100A8 and S100A9. These collective findings not only shed light on the etiology of doxorubicin-induced cardiotoxicity, but also are of potential translational relevance and provide a rationale for the implementation of a targeted intervention strategy to prevent this debilitating side effect.
Huang et al. (Mon,) conducted a other in Doxorubicin-induced cardiac injury (n=6). OCT3 inhibition (genetic deficiency or nilotinib) vs. Wild-type / Vehicle was evaluated on Left ventricular ejection fraction (LVEF) and cardiac troponin I levels (p=<0.05). Genetic deficiency or pharmacological inhibition of OCT3 with nilotinib significantly preserved cardiovascular function and reduced doxorubicin-induced cardiac injury in mice without compromising antitumor efficacy.