CAT and colon carcinoma: Whether this applies as well to cell lines in which catalase-negative peroxisomes have been described, like Morris hepatoma (Mochizuki et al., 1971), rat FTO-2B hepatoma cells (Frederiks et al., 2007), or HT29 cells (derived from human colon carcinoma) (Lauer et al., 1999), is not known.