MGMT and colorectal neoplasm: Figure 2 shows the mass spectra for His-MGMT incubated with two differenthuman colorectal tumor DNA samples (96T and 25T) or with unmodifiedCT-DNA. Both methylated and carboxymethylated MGMT ASPs (m/z 1329.74 [M + H]+ and m/z 1373.73 [M + H]+, respectively) were detected in thesetwo samples, indicating the presence of the respective adducts inboth DNA samples.