Silencing of Rrm1 and Rrm2 markedly enhanced the cytotoxicity of the topoisomerase I inhibitor camptothecin that might be exploited in chemotherapeutic strategies [24, 54] and RRM2 was shown to regulate Bcl-2 in lung cancers and considered to be a worthy target in cancer therapy [55]. This evidence concerns the gene RRM2 and lung cancer.