NOS2 and colon adenocarcinoma: Selective NOS-2 inhibitors L-N6-(1-iminoethyl) lysine 5-tetrazole-amide (SC-51) and aminoguanidine (AG) actually show chemopreventive effect against the incidence of azoxymethane- (AOM-) induced colonic aberrant crypt foci [31], whereas NOS-2 blocker N-(3-(aminomethyl)benzyl) acetamidine (1400 W) is capable of suppressing tumor development in human colon adenocarcinoma DLD-1 xenograft [32].