To specifically examine the effect of inhibition of RET on the anti-tumor activity of macrophages, we employed treatment with either rotenone, which blocks the ubiquinone reduction site of complex I (IQ site) and prevents CoQ from transferring electrons back to CI (Mills et al., 2016; Robb et al., 2018), or MitoQ, which increases ROS under conditions of forward electron transport (FET) and reduces ROS production under conditions of RET (O’Malley et al., 2006). This evidence concerns the gene RET and neoplasm.