Abstract

To explore the role and possible mechanism of integrin alpha 5 in the rat model of bone metastasis of breast cancer. A lentiviral vector interfering with silencing the expression of integrin alpha 5 nucleotide sequence was constructed and transfected into breast cancer BT474 cell line as silent group, blank vector group and control group. The ability of cell growth was detected by cell counting kit-8 method, the ability of cell metastasis was measured by cell scratching method, the invasive ability of cells was determined by Transwell, the cell adhesion was measured by cell adhesion test, the expression of non-muscle myosin heavy chain II and p-S1943 protein was measured by Western blot, and the success rate of tumor bearing, the number and proportion of bone metastases were observed in rats with different carrier cells injected into the left ventricle. The cell survival rate, the number of cells reaching the basement membrane, the number of adherent cells, cell proliferation ability, and the expression of non-muscle myosin heavy chain II and p-S1943 in the silent group (group C) was reduced than that in the blank vector group (group B) and the control group (group A). The success rate of tumor-bearing and bone metastases was 100 % and 75.00 % in the rats injected with blank vector cells, but 71.432 % and 45.45 % in the rats injected with silenced integrin alpha 5 cells, respectively. Silent integrin alpha 5 can effectively inhibit the growth, metastasis and adhesion of breast cancer cells, and inhibit bone metastasis of breast cancer. The mechanism may be achieved by inhibiting the expression of non-muscle myosin heavy chain II and p-S1943 proteins.