MPO, a product of neutrophil-mediated inflammatory responses (Khanna et al., 2018), has been extensively documented to participate in the pathogenesis of various diseases including coronary atherosclerosis (Trentini et al., 2020), stroke (Kim et al., 2019), neurodegenerative disorders (Wu et al., 2020), and malignancies (Rymaszewski et al., 2014). The gene discussed is MPO; the disease is cancer.