Pan-cancer remodeling of reactive oxygen species homeostasis: distinct roles of the ROS-generation and antioxidant arms in immune context and outcome
Reactive oxygen species (ROS) are double-edged in cancer: tumor cells sustain high ROS generation while up-regulating antioxidant defense, so that the net balance between the two arms, rather than absolute ROS abundance, is the biologically meaningful quantity. Whether that balance defines a conserved tumor state across cancer types has been unclear. Here an experimentally measured ROS phenotype, obtained from a three-channel gold-nanocluster array, was generalized to public transcriptomes through a 107-gene ROS program scored in a large cell-line panel and in pan-cancer tumor and adjacent-normal tissue. The optical readout was reproducible and fully discriminative between cell lines, establishing the fingerprint as a quantitative starting point. In tumors, the generation and antioxidant arms were coordinately up-regulated relative to normal tissue, yet the two arms dissociated in their biology. The composite balance score tracked reduced immune infiltration consistently across cohorts, but arm-level decomposition showed that it was carried by low generation-arm activity in immune-cold tumors and followed arithmetically from how the balance score is defined; the association does not implicate antioxidant defense in immune infiltration. The clinical association pointed the other way: adverse outcome was attributable to the antioxidant arm, whereas generation was null. In cohort-held-out validation, tumors were separated from adjacent normal tissue, with redox programs outperforming generic phenotypic programs, indicating that the same program transfers across tumor types. Tumor remodeling of ROS homeostasis is therefore widespread, but its two arms carry distinct meanings: the balance score, driven by its generation term, reports immune context, whereas the antioxidant arm reports clinical risk.