CXCR4 and neoplasm: Notably, Cidofovir pre-treatment markedly abrogated both lung adhesion and invasion of TC-1 cells, completely in 4/6 mice, and in the two remaining mice, only two small microscopic metastatic foci were present 15 days after injection (both comprising 1–2 CXCR4+ tumor cells (Figure 5A, 5B middle panel, 5C, ***P<0.01).