Table 1.

Research goals for brain metastasis-associated reactive astrocytes.

1	Incorporate novel approaches to manipulate astrocytes in vitro (i.e., immunopanning) and in vivo (i.e., GEMM).
2	Apply unbiased genomic and proteomic analysis of reactive astrocytes (single cell level and population level) associated with brain metastasis from different primary sources (i.e., lung cancer, breast cancer, melanoma).
3	Comparison of brain metastasis-associated reactive astrocytes with those present in other brain injuries (i.e., primary brain tumors, neurodegenerative disorders, ischemia, traumatic brain injury, autoimmune disorders).
4	Identify and characterize specific subpopulations within brain metastasis-associated reactive astrocytes and evaluate their potential therapeutic implications.
5	Dissect the biology behind antimetastatic and prometastatic reactive astrocytes: Are they different subpopulations? Do they coexist in time? Could prometastatic reactive astrocytes be transformed into antimetastatic astrocytes?
6	Does systemic disease (primary tumor and extracranial metastases) influence the brain microenvironment acting on reactive astrocytes before metastases are established in the brain?
7	Do brain metastasis-associated reactive astrocytes influence systemic disease outside the brain and/or organismal homeostasis as shown in other brain disorders?
8	Could reactive astrocytes associated with brain metastasis be the source of biomarkers for early diagnosis or response to therapy?