Table 1 The different models for the evaluation of breast cancer brain metastasis
Model | Example | Advantageous | Disadvantageous | Remarks |
|---|---|---|---|---|
MDA-MB-231 | Subline of MDA-MB-231 | Highly metastatic Capacity of being used in the in vivo studies for understanding brain tropism | Poor representation of tumor heterogeneity Genetic engineering and does not reflect the primary tumors | Understanding the genes involved in the process of metastasis including COX2 and HBEGF, among others |
BT474, SKBR3 | HER2-positive | Improving the knowledge towards the breast cancer subtypes participating in brain metastasis | Lack of representation of TNBC brain metastasis | Improving the knowledge towards the HER2-targeted therapy resistance in the brain |
4T1-BR5 | Murine brain metastasis model | The major advantageous of this model is being immunocompetent providing the insight about immune-tumor interaction | Its murine origin decreases the relevance to human breast cancer Poor translational application | Understanding the immune-related mechanisms in brain metastasis |
SUM149, SUM190 | Inflammatory breast cancer-derived lines | Unique properties of inflammatory breast cancer | This is related to the rare subtypes Poor brain metastasis | Highlighting the mechanisms involved in the aggressiveness and metastasis of TNBC |
Xenograft Models | Injection of MDA-MB-231 or BT474 cells | High carcinogenesis The direct injection to the brain mimics metastasis | Because of immunocompromised hosts, it has poor value in immune system interaction studies | Allowing to understand the BBB-penetrating drugs and certain mechanisms in the metastasis |
Patient-Derived Xenografts (PDX) | From human brain metastases | Mimicking the patient tumor and providing the heterogeneity | Low engraftment rates Poor affordability Time-consuming | Valuable for the personalized medicine and understanding the patient response to therapeutics |
Genetically Engineered Mouse Models | HER2/Neu transgenic models | Reflecting the HER2-driven breast cancer malignancy | Slow progression It is not suitable for the high-throughput studies | Highlighting the mechanisms of HER2-positrive breast cancer metastasis to brain tissue |
Orthotopic Models | Direct injection into mammary fat pad | Mimicking the primary tumor growth and metastasis | It rarely leads to the brain metastasis without brain-tropic cell lines | Understanding the metastatic cascades and providing tumor microenvironment interactions |