Expression of cortactin in human breast cancer cell lines with different metastasis potentials / 第二军医大学学报

ABSTRACT

Objective: To screen for human breast cancer sub-cell lines with different metastasis potentials, and to investigate the role of cortactin in proliferation and metastasis of human breast cancer cells. Methods: Human breast cancer sub-cell lines with different metastasis potentials were screened by continuous in vitro invasion assays. Ultra-microstructures of sub-cell lines were observed under transmission electron microscope. The proliferation of sub-cell lines was detected by MTT; the cell cycle was observed by flow cytometry; and the migration ability of sub-cell lines was observed by Transwell assay. The mRNA and protein expression of cortactin was examined by immunofluorescence, RT-PCR and Western blotting assay. Results: Two sub-cell lines with different potentials of metastasis were obtained through continuous in vitro invasion assay, and they showed essentially identical morphology under the transmission electron microscope. The MTT results showed that proliferation of high metastasis cells was faster than that of low metastasis cells (P<0.05). Flow cytometry demonstrated that the proportion of high metastasis cells in G 0/G1 phase was less ([52.67±3.69]% vs [64.46±2.79]%), and that in S phase was more than that of low metastasis cells ([30.53±6.19]% vs [24.63±2.04]%). The proliferation index (PI) of high metastasis cells was higher than that of low metastasis cells ([47.32±3.69]% vs [35.53±2.80]%, P<0.05). Compared with low metastasis cells, the number of high metastasis cells passing through the membrane was significantly more ([61.46± 7.08] vs [25.32±4.87] cells/field, P<0.05). The expression levels of mRNA and protein of cortactin in high metastasis cells was higher than that in low metastasis cells (P<0.05). Conclusion: Over-expression of cortactin is closely related to the proliferation and metastasis of human breast cancer cells.