沉默Bmi-1基因表达对乳腺癌干细胞生物学特性的影响研究

Effects of silencing Bmi - 1 gene expression on biochemical characteristics of breast cancer stem cells

Objective To investigate the effects of silencing Bmi - 1 gene expression of MCF - 7 cells on biochemical characteristics of breast cancer stem cells. Methods A retroviruses vector of the RNA small interference （RNAsi） of Bmi - 1 gene was constructed and transfected into MCF- 7 cells. The stably transfected cells were cultured and passed, which were named as transfeetion group. Set up interference sequence transfection cell group （negative control group） and blank control group. Stem cells were enriched through serum - free alternating serum suspension culture to prepare single cell suspension. Western - blot was used to detect the expression of Bmi - 1 protein, and RT - PCR for the mRNA expression of hTERT and VEGF - C. The results were analyzed by one - way ANOVE, the result of P 〈 0.05 was considered statistically significant. Results The mRNA of hTERT and VEGF - C were expressed as （ 3.46 ± 0.50） and （ 2.98 ±0.18 ） respectively in transfection group, and as （6.88 ±0.21 ）and （5.74 ±0. 29 ） respectively in the blank controls, and as （7.35 ±0.62 ） and（ 6.02 ±0.51 ） respectively in negative control group. Compared with the other two groups ,mRNA expression of hTERT and VEGF - C in the transfection group decreased significantly（ P 〈 0.05 ）. The expression of Bmi - 1 protein in the transfection group （3.31 ±0.19 ） decreased obviously than that in blank control （7.55 ±0. 27 ）and in negative control group （8.10 ±0.32 ） （ P 〈 0.05 ）. Conclusions Bmi - 1 siRNA could effectively interfere with biochemical characteristics of breast cancer stem cells by silencing Bmi - 1 gene of MCF - 7 cells, which provides a new idea for targeted therapy to breast cancer stem cells.