T22-GFP-H6-FdU induces a higher reduction of CXCR4+ cancer cell fraction (CXCR4+ CCF) in liver, lung and peritoneal metastatic tissue, at the end of treatment, than free oligo-FdU, as measured by anti-CXCR4 IHC. In contrast, T22-GFP-H6-FdU or free oligo-FdU does not reduce the CXCR4+ CCF in LN mets or primary tumor tissue after therapy. (N=6 mice per Buffer group; N=7 mice per Free oligo-FdU group and N=8 mice per T22-GFP-H6-FdU group; 3 samples/mouse). Data expressed as mean±s.e.m 