Figure 4: Enrichment of the over-expressing oncogenic form of KRAS, most commonly mutated oncogenes in lung cancer, in male non-smokers vs smokers (A) and female non-smokers vs smokers (B). In response to smoking, 21 genes associated with KRAS oncogene were overexpressing in male smokers and that of 41 genes in female smokers. C) heat map showing the top 50 genes/features representing oncogenic signature gene-sets over-represented in male and female smokers (red=up-regulated, white=average expression, blue=down-regulated). Natural killer cell-mediated cytotoxicity genes down-regulated in female smokers are marked with asterisks along the right edge.