Tissue frozen sections of tissue extracted from xenograft bearing mouse treated with 5. A, FITC-labeled Py-Im polyamide 5 distributes widely in sections of the T47D-KBLUC tumor xenograft. B, High magnification shows nuclear localization of 5 in tumor cells. C, Cardiac muscle sections show a fibrous pattern of fluorescence in the cytoplasm as well as nuclear staining. D, Kidneys demonstrate nuclear localization of 5. E, Liver sections show nuclear localization of 5. F, Bowel epithelia show cytoplasmic fluorescence.