Isolation and characterization of a new cell line from spontaneous mouse mammary tumour, MBL-6, for in vivo cancer studies

In search for treatments against breast cancer, cell lines are one of the basic resources, particularly as in vitro models. Additionally, animal models of cancer are used as the successive step in therapeutics research. In this regard, human breast cancer cell lines provide fundamental models in vitro. However, in vivo studies require immunodeficient mice, which lack the influence of other in vivo factors such as the native microenvironment and the immune system. There are few standard models to study the pathogenic mechanism at molecular level and cell signaling pathway of breast cancer. In this study, a new mouse breast cancer cell line, MBL-6, was successfully established and characterized from tissues of a spontaneous mammary tumor. The cell line had epithelial morphology, formed adherent monolayer, maintained continuously in vitro and was able to form new tumors when injected subcutaneously in syngeneic mice. The growth pattern and metastasis evaluations revealed a considerable in situ duration before invading distant organs. Real time polymerase chain reaction (PCR) analysis showed the expression of ER-, PR- and Her-2 receptors. The chromosome analysis showed numerous chromosomal abnormalities. Aggressive tumorigenecity in tumorigenesis test and the IC50 to cyclophosphamide (CTX), celecoxib (CLX) and cisplatin (CPN) was also evaluated. The numerous tests performed on the new MBL-6 cell line suggest that it is in good quality and may be used in animal models of breast cancer studies.