Fig. 1: IGF2BP3 is upregulated in NSCLC brain metastasis and associated with poor prognosis.

A IGF2BP3 expression was elevated in N2 (n = 74) and N3 (n = 2) stage metastatic tumor compared with N1 stage metastatic tumor (n = 95) in lung adenocarcinoma (LUAD) patients with lymph node metastasis according to TCGA database. Data are presented as median value. B IGF2BP3 expression levels were elevated in brain metastatic tumors (BT) (n = 6) compared with primary lung tumors (LT) (n = 8) in early passage cell lines derived from primary patient samples of lung-to-brain metastases according to GSE110495 dataset. Data are presented as median value. C IGF2BP3 expression levels were elevated in LLC-derived brain metastatic cells (Brm) compared with primary cells according to GSE83132 dataset. Data are presented as mean ± SD; n = 3. D Overall survival analysis of LUAD patients at the N1 stage based on TCGA project was calculated with the log-rank test and stratified by high or low IGF2BP3 expression (high: top 50%, n = 127; low: bottom 50%, n = 126). E–H Pearson correlation analysis between IGF2BP3 expression and key EMT markers (TGFB1, SNAI2, N-cadherin, and MMP9) in LUAD patients according to GSE33532 dataset (n = 100). I Schematic of the subcutaneous tumor and stereotactic brain injection tumor model. J Hematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) analysis of IGF2BP3 and MMP9 in representative subcutaneous tumor and xenograft tumor in the brain from mice. Scale bar = 20 μm. K Quantification of IGF2BP3 and MMP9 expression levels from IHC analysis in J using Image Pro Plus. Data are presented as mean ± SD; n = 3. *P < 0.05; **P < 0.01; ****P < 0.0001 (two-tailed t-test).