Reduced Tca8113 and SCC-9 tumor volumes in nude mice injected with CXCR4-LV1. (a) After six-time injection of saline solution (0.1 ml), NC-LV (0.1 ml), and CXCR4-LV1 (0.1 ml), on day 42, photographs of representative mice and tumors are shown. (b,c) Tumor size was measured using a vernier caliper and tumor volume was determined as described in Materials and Methods section for 42 days. Each data point is the mean value of five to six primary tumors. (d) GFP expression of tumor tissues transduced with CXCR4-LV1 and NC-LV. GFP expression of tumor tissues in different groups were observed, counted, and photographed under an inverted fluorescence microscope ×100. Scale bar = 100 µm. Error bars indicate mean ± SD; **P < 0.01.