In summary, we found that genetic depletion of Prx4 or Prx4/Srx has no effect on tumor incidence of mice receiving urethane treatment, but leads to significantly reduced number and size of tumors with decreased cell proliferation, suggesting that the loss of Prx4 or Prx4/Srx renders mice partially resistant to urethane-induced lung tumorigenesis. This evidence concerns the gene PRDX4 and neoplasm.