CD34 and neoplasm: We then immunostained CD34 protein in these tumor xenografts for calculation of microvessel density and found that docetaxel alone could significantly reduce microvessel density in tumor xenografts compared to the negative control group (29.9 ± 1.92 vs. 20.75 ± 1.96, P < 0.05), while the high dose of icotinib alone only mildly reduced microvessel density in tumor xenografts (29.9 ± 1.92 vs. 25.09 ± 2.41, P < 0.05; Table 2 and Figure 3).