PDX model of BC in the study of plasticity of tumor cells in the process of metastasizing

Introduction. Mouse models using primary patient’s tumors (patient-derived xenograft, PDX) are an effective tool for studying the mechanisms of metastasizing. Tumor plasticity, i.e. the phenomenon of cell phenotype change in response to dynamic microenvironmental conditions is one of the key processes basic to metastasizing. The aim is to study the plasticity of tumor cells in metastasizing using the PDX model of breast cancer as an exemplary case. Materials and methods. Balb/c nude mice (♀, 8 weeks) were used to develop a xenograft model. In the 1st experiment, a suspension of primary tumor cells obtained from the surgical material of breast cancer was injected subcutaneously into the back area with the DMEM medium and Matrigel in a volume of 100 μl. In the 2nd experiment, a fragment of the primary tumor was implanted into the mammary gland area with suturing; after the formation of the vascular network, it was removed. Phenotyping was performed by flow cytometry (NovoCyte 3000 ACEA Biosciences, Agilent, USA) using antibodies to CD45, EpCam, CK7/8, CD44, CD24, N-cadherin.