Abstract: Objective To efficiently builds up and expand breast cancer cells from patient cancer tissue and identify their biological properties, to provide abundant materials for research and personalized medicine. Methods Feeder cell layer and ROCK inhibitor Y-27632 were employed to faciliate the breast cancer cells；CCK-8 was used to determine the proliferation of the breast cancer cells; Cell cycle distribution was analyzed by flow cytometry; Histochemistry(FH) assay to show the expression level of CK. The mRNA expression levels of HER-2, ER, PR and the breast cancer stem cell associated molecules (such as CD44, CD24, etc.) were detected by RT-PCR；STR assay was used for identifying verification of the cells. Results The use of feeder cells and Y-27632 facilitates rapid expand of the original breast cancer cells, and the cells have kept the original features of the tumor. Conclusion To use the method could obtain a large number of cells within a short time, which can promptly be used for the research of personalized medicine.

Key words: 3T3Swiss, feeder cells, Y-27632, primary culture, breast cancer