NOX4 and neoplasm: We have previously shown that sequestering ROS with an antioxidant (manganese porphyrin, MnTE) significantly suppressed M2 macrophage phenotype and that expression levels of Nox1 and Nox4 are not significantly different in M1 vs M2 macrophages (20), implying that Nox4 is not a contributing source of ROS that promotes M2 or tumor-associated macrophage function.