KRAS and lung carcinoma: Surprisingly, in view of the data in Fig. 2 indicating that deletion of KRAS4A in human carcinoma cells in vitro causes some growth inhibition, GO enrichment analysis of genes highly expressed in primary lung carcinomas with low KRAS4A levels identified pathways linked to the cell cycle, microtubule organization, mitosis, and DNA damage responses (Supplementary Table 3).