BMI1 and neoplasm: In vivo treated with Free PTX, mPEG-CS/PTX, mPEG-CS-cRGD/PTX and mPEG-CS-cRGD/Bmi-1RNAi-PTX, protein of the mouse tumor tissues expression levels of Bmi-1 and C-myc were gradually reduced compared to the Control group, and the protein expression of Bmi-1 in the four groups were 0.899 ± 0.0169 (p < 0.001), 0.827 ± 0.020 (p < 0.001), 0.645 ± 0.016 (p < 0.001) and 0.406 ± 0.010 (p < 0.001) for Bmi-1.