Albeit CBX3, EGFR and RAC1 genes map inside three vast regions of the short arm of chromosome 7, namely 7p15.2-14.1, 7p12.3-11.2 and 7p22.3-21.1, respectively, which are also frequently amplified in lung adenocarcinoma [21], very little is known about the genetic and functional interactions in vivo occurring among CBX3 and either EGFR or RAC1 proto-oncogene and how they contribute to cancer aggressiveness and patient survival. This evidence concerns the gene CBX3 and lung adenocarcinoma.