Table 1.

Comparison of differentially expressed and regulated genes, molecules, signatures, and cell in primary tumor versus brain metastases.

Increased abundance or expression in primary tumor	Increased abundance or expression in BM	Decreased abundance or expression in BM
CD4+ T cells	Mutations in STK11, FAM129C, ADAMTS, and APOBEC signature	Th1 and CD8 T genes
CD8+ T cells	TMB	Expression of VCAM1
CD+ FOXP3	Higher number of somatic mutations	Leukocyte extravasation signaling
PD-L1 expression*	Higher variant allelic frequency of mutated genes.	Th1 immune response
	Invasion, metastasis, and metabolic-associated pathways	Reduced T cell heterogeneity
	Alterations in Hippo pathway	Dendritic cell maturation
	PD-L1 expression*	CD8+ T cells
		Macrophages (not TAMs)
		CTLA-4

*Discordant results.