Establishment of recombinant lentiviral vector with ABCG2 overexpression and effects of the recombinant on human breast cancer MCF-7 cells’ biological characteristics

Aim of the study: ATP-binding cassette super family G2 (ABCG2) is recognized as the key point of the cancer cells’ resistance to chemotherapy drugs. But there have been rare reports about the relationship between ABCG2 and the invasion, migration and animal tumor formation abilities of cancer cells. We want to establish a recombinant lentiviral vector with ABCG2 overexpression, and study the vector’s effect on human breast cancer MCF-7 cells’ biological abilities above to improve our understanding about ABCG2.

Material and methods: The recombinant lentiviral vector with ABCG2 overexpression was transfected into human breast cancer MCF-7 cells. The cells’ abilities of migration and invasion were tested by wound healing assay, and transwell invasive assay. The MCF-7 cells infected were injected in the left back of the nude mice. In the meantime the MCF-7 cells without anything were injected in the right back of same nude mice as the control group. Western blotting was used to detect the expression of ABCG2 in MCF-7 cells infected, the transplantation tumor tissue and the control group MCF-7 cells.

Results: The recombinant lentiviral vector with ABCG2 overexpression infected human breast cancer MCF-7 cells successfully, and the transfection efficiency was 95.4 ±2.8%. The wound line of MCF-7 cells infected healed after 48 hours, but the line of control group MCF-7 cells still existed. The number of the cells going through the membrane in infected MCF-7 cells was 78.34 ±0.25, and the number in control group MCF-7 cells was 15.28 ±0.12, p < 0.05. A much bigger transplantation tumor appeared in the MCF-7 cell infected nude mice. The expression of ABCG2 in infected MCF-7 cells and the transplantation tumor tissue was significantly higher than that in control group MCF-7 cells, p < 0.05.

Conclusions: We obtained ABCG2 overexpression in human breast cancer MCF-7 cells which showed the increasing migration, invasion and animal tumor formation abilities. Therefore, the results revealed that there might be a relationship between overexpression of ABCG2 and MCF-7 cells with increasing invasion, migration and animal tumor abilities.