Abstract: Objective To establish primary breast cancer cell lines from patient tissues and offer a new cancer cell model for basic research. Methods Breast cancer biopsy tissues were digested with type Ⅱ collagenase and cultured in BCMI medium. When the cells proliferated rapidly, the medium was switched to DMEM. STR genotyping was performed to identify specific genetic markers of the four primary breast cancer cell lines. Colony expansion assays and sphere formation assays were conducted to analyze its tumorigenicity. Real-time PCR and Western blot experiments were used to analyze the expression of the epithelial-mesenchymal transition (EMT) molecule markers. Migration and invasion assays were performed to assess the metastatic potential of the primary breast cancer cells. Results We established four primary breast cancer cell lines: BC25#, BC51#, BC56#, and BC57#. These cell lines were cultured in DMEM medium, passaged multiple times and tagged with details about their clinical past. STR genotyping identified specific genetic markers for each of the four primary breast cancer cell lines. Clonogenic and sphere formation assays revealed that the four lines have a stronger tumor-forming capability compared to the classic breast cancer cell line T-47D. Real-time PCR and Western blot experiments showed that, compared to T-47D, the four primary breast cancer cell lines have decreased E-cadherin expression and increased vimentin expression. Migration and invasion assays indicated that BC25# had a higher metastatic potential than the traditional breast cancer cell line T-47D. Conclusions Four primary breast cancer cell lines, BC25#, BC51#, BC56# and BC57# are successfully established, which may act as new cancer cell model for laboratory research of breast cancer.

Key words: primary breast cancer cell lines, basic research, new cancer cell model