ITGB2 and small cell lung carcinoma: Moreover, an external validation (Figure 3G) using independent RNA-seq data from SCLC cell lines 42 confirmed the improvement of the SCLC-ITGB2-sig (ES = 0.77; FDR = 0.50) as compared to the KEGG-SCLC category (ES = 0.42; FDR = 0.82).