Fig. 1

TRIM28 plays a mechanistic role in tumor progression by recruiting MDSCs into the tumor microenvironment. (A) TRIM28 expression levels in different tumor types from TCGA database were analyzed by TIMER2.0 (*p < 0.05, **p < 0.01, ***p < 0.001). (B) Survival analysis comparing the high and low expression of TRIM28 in lung adenocarcinoma according to TCGA dataset by using the website GEPIA 2 (http://gepia2.cancer-pku.cn/#survival). The high or low expression of TRIM28 were divided according to 50% of the total sample. (C) Immunohistochemical analysis of TRIM28 protein levels in NSCLC samples on tissue microarrays. Representative examples of TRIM28 expression in adjacent non-cancerous lung tissues, NSCLC tissues are shown. The scale bars represent 100 μm. (D) Overall survival analysis of patients with NSCLC stratified by the TRIM28 expression level in 90 samples. Kaplan-Meier survival analysis indicating a significant association between higher TRIM28 expression and poorer OS in NSCLC. (E) The correlations of TRIM28 expression and MDSCs infiltration in pan-cancers were analyzed by TIMER2.0. (F) Correlation of TRIM28 expression, tumor purity, and MDSCs infiltration in TCGA lung adenocarcinoma (LUAD) and lung squamous cell cancer (LUSC). The expression of TRIM28 positively correlates with MDSCs infiltration in NSCLC. (G-H) Representative immunofluorescence staining of CD14 and TRIM28 in tissue from human lung adenocarcinoma and the correlation between TRIM28 and CD14 intensity. The expressions of TRIM28 and CD14 were measured with mean fluorescence intensities (MFIs) (in arbitrary units, a.u.), respectively. The pearson correlation between TRIM28 and CD14 expression (n = 90; p < 0.01, r = 0.567). Scale bars: 50 μm. (I-J) Cox regression analyses using data from TCGA indicated that high MDSC infiltration was significantly associated with poorer prognosis in NSCLC. Furthermore, elevated TRIM28 expression and a high proportion of MDSCs significantly correlated to poorer OS compared to their counterparts, strongly suggesting that TRIM28 influenced patient prognosis through an immune-related mechanism. Split infiltration percentage of patients: 50% (I). Split expression percentage of patients: 50% and split infiltration percentage of patients: 50% (J)