RRM2 and small cell lung carcinoma: Interestingly, most of the differentially regulated genes in miR-1 overexpression system contribute to the progression of SCLC; however, RRM2 is one of the top differentially regulated targets (among top 15 DEG), therefore on the basis of interactome analysis and GSE analysis (in miR-1 overexpression/knockdown system), we selected RRM2 as a prominent target of CXCR4/FOXM1 axis.