Expression data on freshly isolated lungs from Atf4wt/wt and Atf4D/D mice.

Since acute deletion of host ATF4 caused a significant tumor-inhibitory phenotype, and since activated CAFs also play a critical role in the establishment of the metastatic niche we speculated that ATF4 deficiency could also result in an inhibitory effect on lung metastasis. Thus, we examined the impact of host ATF4 deletion in the pre-metastatic niche by analyzing gene expression changes on lungs from Atf4wt/wt and Atf4D/D mice at 4 weeks post tamoxifen treatment. Genome-wide microarray analysis identified 21 genes to be significantly downregulated in Atf4D/D lungs, including collagen-associated genes. Also, pathway analysis on the most dysregulated genes revealed defects on collagen formation, extracellular matrix organization and integrin cell surface interactions pathways. Lungs were isolated from Atf4wt/wt and Atf4D/D mice for RNA extraction and hybridization on Affymetrix microarrays.