Fig. 5: CircFNDC3B attenuates CD8⁺ T cells infiltration through TFII-I /STAT1/CXCL10-CXCL11 axis.

A The correlation of CXCL10 or CXCL11 expression with tumor purity or CD8⁺ T cells infiltration (Tumor-immune estimation resource, TIMER) (https://cistrome.shinyapps.io/timer/). B IF staining of CD8 (green) in sections of NSCLC tissues with high or low circFNDC3B expression. Nuclei were stained with DAPI. C The proportion of CD8⁺ T cells in sections of NSCLC samples with low (n = 50) or high (n = 50) circFNDC3B expression. Patients were divided into groups by the median circFNDC3B expression. The proportion of CD8⁺ T cells were analyzed by ImageJ following the standard protocols and tutorials provided by the software. Data were displayed as mean ± SD. (Student’s t-test, ***P < 0.001). D The chemotaxis of CD8⁺ T cells towards the supernatants of A549 cells stably overexpressing circFNDC3B or control vector with or without rhCXCL10 and rhCXCL11 treatment. Data were displayed as mean ± SD, (one-way ANOVA, n = 3, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001). E The chemotaxis of CD8⁺ T cells towards the supernatants of A549 cells after circFNDC3B knockdown with or without anti-CXCL10 and anti-CXCL11 treatment. Data were displayed as mean ± SD. (one-way ANOVA, n = 3, **P < 0.01). F The chemotaxis of CD8⁺ T cells towards the supernatants of A549 cells preferentially transfected with either circFNDC3B or TFII-I overexpression plasmids. Data were displayed as mean ± SD. (one-way ANOVA, n = 3, **P < 0.01, ***P < 0.001). G The chemotaxis of CD8⁺ T cells towards the supernatants of A549 cells preferentially transfected with either circFNDC3B or STAT1 overexpression plasmids. Data were displayed as mean ± SD. (one-way ANOVA, n = 3, **P < 0.01, ***P < 0.001).