SOD1 and neoplasm: Colonic and hepatic tumor over-expression gene 14 (CH-TOG; 1.80-fold) induction may also suggest active anti-tumor response, while the induction (2.12-fold) of superoxide dismutase (SOD), which plays a role in scavenging free radicals during oxidative stress [34,53] and helps eliminate reactive oxygen species, free radicals, and reactive intermediates sometimes produced during PAH metabolism [47], is indicative of oxidative stress response.