A recent study by Lilljebjörn et al., which evaluated HO-1 expression in mice tissues upon E. coli infection, showed that the increase of HO-1 itself and/or carbon monoxide are capable of preventing the development of prostatic intraepithelial neoplasias and the growth of prostate tumors, apparently through the modulation of pathways involved in fatty acid and lipid metabolism in macrophages and epithelial cells [70]. This evidence concerns the gene HMOX1 and prostate intraepithelial neoplasia.